TUS INHERITANCE OF RESISTANCE TO ÜSTILAGO NUDA (J E N S .) K . AND S , , RACE I , IN BARLEY By Voustapha Ibrahim Zeidan A THESIS Submitted to the School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Botany and Plant Pathology 195:3 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Tî-îE IN H E R ITAN C E OF RESISTANCE TO USTILAGO NUDA ( J E N S .) K. M ID S . , RACE I , IN BARLEY By Houstapha Ibrahim Zeidan AN ABSTRACT Submitted to tbe School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Depatment of Botany and Plant Pathology 1953 Approved Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Barley has been knoiim for centuries as a cultivated plant used for making bread and as feed for animals. This crop is attacked by many diseases ’which become imnortant factors in decreasing yields. Loose smut caused by Ustilago nuda (Jens.) K. and S. is one of these diseases. Its control by the hot water treatment, modified hot water treatment and by organic compounds is unsatisfactory and hazardous. Consequently the use of resistant varieties is the effective method. The present investigation was concerned with the inheritance of resistance to Ustilago nuda (Jens.) K. and S., race I, the genetic con­ stitution of. the parental varieties and the relationship between factors for resistance and those for morphological characteristics. Four non-commercial varieties (Jet, Anoidium, Harlan, Ogalitsu) resistant to loose, smut disease were crossed into all possible combina­ tions: Jet X Harlan, Jet x Anoidium, Jet x Ogalitsu, Harlan x Ogalitsu, Harlan x Anoidium, and Ogalitsu x Anoidium. Jet has a two-rowed head, naked seeds, rough awns, a black lemma and pericarp. The others have six-rowed head, covered seeds, white lemma and pericarp. Harlan and Otalitsu have semi—smooth awns, while the awns of Anoidium are smooth. The florets of one or two heads of plants were inoculated. One or two drops of fresh snore suspension ’.vere introduced into each floret by means of the "needle" method. The classification of families which represented the Fg plants, into resistant, segregating and suscep­ tible groups was made according to the percentages of infection. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The inheritance of resistance to Ustilago nuda (Jens.) K. and S., race I, in the crosses Jet x Harlan, Harlan x Ogalitsu, Ogalitsu x Anoidium, is explained by two gene pairs acting in duplicate dominant epistatic condition. The two genes were found to be different and independently inherited. pair for resistance. Thus, each parent possesses one dominant gene One gene difference was found between two-rowed vs. six—rowed head, covered vs. naked seeds, black vs. white lemma and pericarp in the hybrids of Jet x Harlan. Also, no linkage was found to exist between factors for resistance and those for the above mentioned moiphological characteristics. The inheritance of resistance in the cross Jet x Anoidium and Jet x Ogalitsu was not studied, because of the inadequate number of families. In the cross Harlan x Anoidium, the resistance was interpreted in terms of two gene pairs exhibiting dominant and recessive epistasis. inherited. The genes also were different and independently The expected ratio was 1^:1 but the observed ratio was 13:3. However, the excess of susceptible families could be interpreted by the occurrence of fluctuation in some genotypes, which might be due to a change in the expression of the resistance and the susceptibility. might be influenced by the environment. This change Thus, each parent also possessed one dominant gene. Four genes were found to govern the resistance in the four varieties used in this investigation. These genes were found to be different and to be independently inherited. There was no evidence of linkage between resistance and morphological characters. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNO'ArLEDGl\ffiMTS The author wishes to express bis sincere gratitude to Doctor John R. Vaughn and Doctor Kenneth J. Frey for their effective guidance and criticis'n in carrying out this investigation. He is also greatly indebted to Doctor Villia'n 3, Drew for his kind and valuable advice and criticisoi along the preparation of this ■oanuscript, The author wishes to thank Doctor Constantine J. Alexopoulos, Doctor Eldon E, Down and Doctor Jesse E, Muncie for their careful criticism of this thesis. Finally, he deeply appreciates the people of Lebanon for the financial help by which he was assisted in completing his training in the United States of America. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS I. II. I N T R O D U C T I O N ................................................. 1 A. Economie importance of b a r l e y ............................ 1 B. Economie importance of thed i s e a s e ................... 1 C. Practical control m e t h o d ......... 2 D. Objectives of the study ..................... 2 REVIEW OF L I T E R A T U R E ........................................... '3 A. History of loose smut organism Ustilago nuda (Jens.) K. and S r a c e B. C. I ........................................... 3 Inheritance of resistance to Ustilago nuda (Jens.) K. and S ...................................................... ^ Inheritance of agronomiccharacters........................ 7 1. Two-rowed vs. six—rowed h e a d s .............. 7 2. Naked v s . covered s e e d s .......... 9 3. Rough awns vs. smooth awns U« Black lemma and pericarp vs. white lemma and pericarp . 11 , .........................10 D. Linkage studies .......... 11 E. Infection of hybrid progenies.............................. 12 III. MATERIALS AND T^ETHODS........................................... lU IV. EXPERIMENTAL R E S U L T S ........................................... 21 A. Study of the reaction of the parental varieties Jet, Anoidium, Harlan and Ogalitsu toloose smut infection . . . B. 21 'Study of the inheritanceof resistance in h y b r i d s ............21 1. Jet X H a r l a n ............ 2. Jet X A n o i d i u m .........................................26 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 21 C. D* 3, Jet X O g a l i t s u .................................... .. 28 h» Harlan x O g a l i t s u ....................................... 28 5» Harlan x A n o i d i u m .................................. 6. Ogalitsu X A n o i d i u m .................................... 33 31 Study of the inheritance of agronomic c h a r a c t e r s ...........37 1. Two-rowed vs. six-rowed h e a d s .......................... 37 2• Hulled vs. naked seeds 3. Rough awns vs. smooth awns U. Black lemma and pericarp vs. white lemmaand pericarp • ............................ UO ........................ Ul U3 Study of the linkage r e l a t i o n s .............. ............ 1. Resistance vs. susceptibility withtwo—rowed vs. six-rowed h e a d s ....................................... 2. Resistance vs. susceptibility with hulled vs. naked seeds 3. ............................................... U6 Resistance vs. susceptibility with black lemma and pericarp vs. white lemma and p e r i c a r p ................ U7 V. S E L E C T I O N ....................................................... k9 VI. D I S C U S S I O N ..................................................... $0 VII. sumuiRY .......... 55 LITERATURE C I T E D ................................................... 57 A P P E N D I X ........................................................... 62 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. INTRODUCTION The barley crop has been known for centuries as a cultivated plant for making bread and as a feed for animals. In addition, it is also used today in nanufacturing items for human consumption: flour.and spiritous liquors. breakfast food, Barley is grown under a wide range of environmental conditions in many countries of Asia, Europe, as well as in the United States of America. In the United States, barley production is concentrated in the mid­ west states: North Dakota, Minnesota, South Dakota, Wisconsin, Michigan, Iowa, Illinois, and in the far west in California. It was reported that California was the leading barley producer in 19^1. Michigan during the same year produced 3,876,000 bushels of barley grain having a revenue of oU,692,000 which amount gives barley fourth rank after corn, wheat, and oats in crop income (1, 10, 39). It is true that barley does not occupy first place among the small grains but it is an important crop, especially for animal consumption. Barley can compete with oats for this purpose, and in many places in the United States barley is more profitable and produces more bushels per acre than oats. soil (23). Besides these benefits, barley is used for breaking new Its early maturation allows it to be cut before many other species which have mature seed. It is also used for old lands which have become too poor for producing good crops of wheat or c o m . ' Barley is affected by manj»" diseases which decrease its production quantitative!:/- and qualitatively. Important among these barley diseases are the smut diseases (loose, semi—loose and covered). Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 2 Of the snut diseases, loose snut caused by Ustilapo nuda (Jens.) K. and S. is discussed in this paper. It is known (53) that within the spe­ cies there are various■biological forms, but the present study is confined to race I. Loose smut is not normally a dangerous disease, but it becomes an important factor in reducing the yield in those years during which the environmental conditions are favorable for the growth and the spreading of the causal fungus which occurs often in humid and subhumid areas. It has been stated (2, 3, 9, 13, 26) that the organism hibernates within the seeds in its vegetative form. Semeniuk (62) reported that the barley yield decreases approximately in direct proportion to the percent­ age of smutted plants. Consequently, the control of the loose smut organism consists in destroying the dormant mycelium within the seed without damaging the viability of the embryo. It was found that the use of hot water treatment, modified hot water treatment, and of many mercuric compounds for controlling the loose smut disease (29, 32, 3U, 5U, 55, 57, 71) were unsatisfactory and hazardous. For these reasons, the ideal method for preventing loose smut infection would be breeding for resistance. But to be able to obtain a good stock of resistant varieties, it is import­ ant to Icnow about the inheritance of the resistance. Therefore, the object of this thesis is the study of the inheritance of resistance in the progenies of four varieties of barley which proved to be resistant (Table l) to loose smut infection, determination of the genetic constitution of the parental varieties, and the relationship between the factor or factors for resistance and those for some important morphological characters. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. REVIEW OF LITERATURE A. History of Loose Sriiut Organism Ustilago nuda (Jens.) K. and S. race I Smut history is discussed here according to Jensen (29), Kellerman and Siringle (32), Stakman (65), and Reed (h8). Plimus (UU) in his Naturalis Historiae discussed the effect of weather and location on smut of cereals. Dodens (l5) reported that smut was found on oats and wheat. He described them an unfruitful herbs, blackened or blighted. (U6) gave two names for barley smut: Lobelius Ustilago pulystichi and Ustilago ■ horde i dis ty chi. Per soon (Ii3) placed the smuts among the fungi. In-the eighteenth century knowledge of the smut fungi increased among scientists, but they did not know the real difference between loose and covered smuts. Prévost, 130? (Ii7), found that the spores which had been considered abnormal cells of the host were able to germinate. After­ ward much became known about spore structure, development of mycelium from the spore, methods of infection, and development of spores. Dittmar (lU) names the loose smut organism Ustilago segetum, while Tulasne (6b, 70) named it Ustilago carbo. The knowledge of fungi in general increased as investigators started to search for something new which would shed more light on the field of fungi. Many phenomena had been observed between the fungus and the host among which was the discovery of physiological races of well-defined morphological species of parasitic fungi, a discovery which was one of the important developments in plant pathology of that time. This distinc­ tion between these races was based upon the ability of the fungus to attack Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. h one host plant and not another. The first investigator to call attention to that ohenomenon was Schroeter (60, 6l) who, in studying spore germina­ tion of the smuts, observed an abundant production of poridia in the oat smut and covered smut of barley and who names the barley smut; Ustilago hordei. He also reported that the smut of oats was incapable of infecting the barley. Jensen (29) gave loose smut the name Ustilago segetum var. hordei nuda; and covered the name Ustilago segetum var. hordei tecta, on the basis of difference in color, size and character of the spore mass. Kellerman and Swingle (32) studying the germination phenomena of spores which were obtained from various loose smuts, were able to separate them into four species; 1. Loose s"iut of wheat - Ustilago tritici. 2. Loose smut of barley - Ustilago nuda. 3. Loose smut of oats - Ustilago avenae. U. Covered smut of barley — Ustilago hordei. Meanwhile, investigations on physiologic specialization advanced. Various terms had heen found to apply to these races which were distinguished only by their physiological behavior in the choice of the hosts. Schroeter (60) gave the races the names of "sister species" (species sorores) and Hitch­ cock and Garleton (26) names them: physiological species. Maddox (37) and Brefled (?) were the first to indicate that the infection in young ovaries of wheat and barley by Ustilago tritici and Ustilago nuda occurred at flowering time. Rodenhiser (52, 53) reported that physiological specialization did occur with the species Ustilago nuda and Ustilago tritici, and he found more than one form in Ustilago nuda. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 2 Ruttle-Nebel (56) discovered abundant mycelium in the pericarp, in the crushed nuoellus, in the aleruone and in the endosperm of the seed and in the souteH u m and hypotocyl of the embryo. She also observed that penetration of hyphae of Ustilago nuda occurred at various points along the ovary wall. B. Inheritance of Resistance to Ustilago nuda (Jens.) K. and S. in Hybrids The problem of inheritance of resistance is very important for breeders and pathologists today. The first to study the inheritance of resistance and susceptibility to yellow rust (Puccinia glumarum) in the progenies was Biffen, 1905 (li) who crossed two varieties of wheat: Michigan Bronze with Rivet. The first variety was very susceptible, but the second was somewhat "immune" to the disease. From his results he concluded that the resistant character was governed by one gene and that susceptibility was dominant over "immunity". Nahmmacher ()tl) crossing many resistant with susceptible varieties of barley failed to provide an exact analysis of the factors governing the reaction in the progenies. Zeiner (?U) making genetical studies of eight crosses between resistant and susceptible varieties of barley found that "immunity" or slight susceptibility to loose smut was consistently inherited according to the Mendelian ratio. In a cross between a moderately susceptible variety (Heil's Franken) and highly susceptible variety (Australian Early), he found a transgressive segregation in the direction of greater suscep­ tibility, and he also discovered resistance was governed by one Mendelian Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 6 factor exceot in one cross (Hell' Franken x Walpersi) in which resistance was found*to be governed by two factors. Resistance appeared to be dominant although the evidence was not conclusive, Livingston (35) studied the inheritance of resistance in the hybrid progenies and in subsequent generations, He adopted the partial vacuum method of inoculation described by Moore (Uo) throughout the investigation, and made several crosses and reciprocal crosses between susceptible and resistant varieties. He used Colsess and Missouri Early Beardless as susceptible varieties; and Trebi and Hordeum deficiens as the resistant varieties. According to the figures obtained, Trebi and H, deficiens possessed a dominant factor for resistance. When he crossed Missouri Early Beardless with either variety, Trebi or H, deficiens, a similar reaction was obtained in the F 2 generation. This similarity in reaction indicated that the factors for resistance carried by the two resistant varieties exertbd a similar effect. He also found no correlation to exist between factors for resistance to loose smut and those which governed hooded and six-rowed heads. Schaller (58) also studied the inheritance of resistance to loose smut, Ustilago nuda, in hybrids of several crosses. were: The varieties used Trebi (resistant), Newal (susceptible). Jet (resistant), and Dorsett (resistant). Re used the "needle" method of inoculation described by Shands and Schaller (63). The inoculum used was collected originally from a single smutted head occurring naturally in the susceptible variety (Newal). In the cross between Trebi and Newal and their back cross, resistance in Trebi was governed by a single dominant gene. similar results in the hybrids of the cross Jet x Colsess IV. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. He also found But in the 7 cross Dorsett with Selection x 173-10-^-6-1, he found a transgressive segregation toward susceptibility, Fro^n this it was concluded that the genes which govern the resistant characters in Dorsett and Selection 173-10-^—6—1 were different fro^ th^se of Jet and Trebi which were also different fro’n each other. His investigation showed that four gene pairs were found to be responsible for controlling the character of resistance, and that the factor of resistance was doninant over susceptibility. C. Inheritance of Agronomic Characters Many of the agronomic characters of barley varieties are important from an economic standpoint. Because of that importance, many investi­ gators have studied the genetical constitution and the behavior in the progenies of crosses made for that purpose. The agronomic characters which are studied in the present paper are: two—rowed versus six-rowed heads; rough versus smooth awns; hulled versus naked seeds and black versus white lemma and pericarp of seeds• 1. Two-rowed vs. six-rowed heads. The genetical constitution of tow characters has been studied by many investigators who have emphasized the fertility of the lateral florets as the basis of their studies. All cultivated varieties of barley, according to Jessen, 18^5 (30), belong to one species : Hordeum sativum. Buckley (8) classified the species Hordeum sativum into four groups on the basis of the lateral florets. a. Hordeum sativum vulgare; Lateral florets completely fertile. b. H. sativum'intermidium: c. H. sativum distichon: Lateral florets staminate. d. H. sativum deficiens: Lateral florets partially fertile. Lateral florets sexless. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 8 Biffen (^) made several crosses between different varitiss of 2-rowed vs. 6-rowed heads, and in eaci case found that the 2-rowed differed from 6-rowed by one single factor: the 2-howed character was dominant over 6-rowed character. Ubisch (72) studied the segregation of 2-rowed barleys, distichon, and 6-rowed barleys, vulgare. He explained the difference between these two characters on the basis of two factors, but the dominance was not complete. Harlan and Hayes (22) in crossing 2-rowed with 6-rowed varieties found that in most cases an intermediate form was obtained in the generation, and that the lateral florets were awned and very Icnv in fertility. In addition, they found that segregation in the Fg generation could be explained on the basis of a single factor difference. In a cross between Manchuria, a 6-rowed variety in which the lateral florets are fertile and long-awned, and Svanhals, a 2-rowed variety with long-awned fertile central florets and awnless, sterile lateral ones, the results supported the two factors pair hypothesis. Engledow (16) concluded, according to his own observations which were based upon the fertility of the lateral florets, that H. deficiens, H. distichon and H. vulgare formed an allelomorphic series. The dominance existed in the order of deficiens, distichon and vulgare. Griffee (21) too, studied the fertility of the lateral florets using H« deficiens stendelii, a 2-row variety in which the lemma and palet of of the lateral florets are slightly or not at all developed. is a variety with 6 rows. several In the Manchuria generation under the field conditions, plants showed slight development of the glumes and palets in Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 9 the lateral florets. three types: In the generation the plants were grouped into deficiens type, intermediate, and 6-rowed in a 1:2:1 ratio. In another cross, however, Svanhals x Lion with the results obtained results confirmed found by Harlan and Hayes (2h) . Gillis (19) supported the two factor hypothesis of Ubisch between 2-rowed and 6-rowed, but added a third factor, D, for fertility of the lateral florets. Neatby (L2) Tedin and Tedin (66) stated that there was one single factor difference between 2-rowed and 6-rowed heads. Robertson (1x9) reported the presence of a one gene difference in one cross, and the presence of a two-factor difference in another cross between 2-rowed and 6-rowed. In the latter, the dominance was incomplete. Daane (13), Living­ ston (35) and Schaller (53) stated one sinrle gene difference for 2-rowed vs. 6-rowed character. 2. Two-rowed character was dominant. Naked versus covered seeds. The inheritance of the factors for naked and covered seeds has been studied extensively by many investigators who all agreed on the mode of inheritance. Biffen (5) made several crosses finding that the difference between the hulled and naked was based upon one single factor: was dominant over naked. the hulled factor Hor (28) stated there is one single factor difference between hulled and naked character. Neatby (li2) studied the hulled vs. naked conditions in the seed by crossing Guy Mayle with Canadian Thrope. The former was 6-rowed, hulless, early, shortj the latter was 2-rowed, hulled, late, tall. In the Fg generation, he found a 3:1 ratio (three hulled and one naked). He concluded that there existed Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 10 one sinrie factor difference between hulled vs. naked. Tedin and Tedin (66), Fayes and Garber (25), Robertson (h?), Buckley (8), Daane (11), and Schaller (58) have all reported the occurrence of one single factor dif­ ference between hulled and naked: 3. hulled was dominant over naked. Rough versus smooth awns. Because of the commercial importance of rough and smooth characters their inheritance has been studied by many investigators. Harlan (22) studied the inheritance of rough vs. smooth awns and found the progenies in generation were rough. tion segregated into three rough, one smooth. The genera­ The rough character was dominant over the smooth character. Griffee (2l) also made a cross between Svanhals and Lion finding that the first had rough awns and the second had smooth awns. He reported the results obtained could be explained on a basis of three rough to one smooth. Sigfusson (6U) crosses Bearer x Lion and Chinese x Lion (Bearer and Chinese were rough awned but Lion was a smooth awned). All the F^ generation had rough awns. groups: In the Fg generation, he classified four rough, intermediate rough, intermediate smooth and smooth. He stated roughness in barley was controlled by two complementary factors and designated them: R and S. R and S were together. The rough character was expressed when If R factor was absent, the phenotype produced was intermediate smooth. was intermediate r^ugh. If S factor was absent, the.phenotype produced The smooth phenotype was obtained in the absence of both factors R and S . David (12), Robertson (1|9), and Schaller (58) found that segregation between rough and smooth awns was based upon one sinrle gene difference: rough character was dominant over smooth. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 11 li» Black lemma and pericarp versus white lemma and pericarp. The inheritance of the color in the paleae also has been studied extensively by many previous workers. Biffen (51, Griffee (21), Hays and Garber (25), Robertson (U9), Buckley (8), Daane (11), Powers (U6), Schaller (58) and Woodward (73), stated that black and white color in rlûmes differed by one single factor pair, and that black was dominant over white. Biffen (5) and Duckelv (8) found that the black vs. white color of the seeds and of the oalea were coverned by the same gene. D. I.inkage Studies Since the parents used in this investigation differed in several agronomic characters, it was important to study the relationships between these agronomic characters and the resistance or susceptibility. 1931 (20) Coffman, reported there was little or no correlation between lemma color and other agronomic characters, or between the factor for resistance and the factor governing lemma color. Kilduff (33) studied the relations between the agronomic characters and the resistance to bunt in wheat by crossing Koba variety with Red Bobs variety. Koba variety, vhich was susceptible to bunt and loose smut, had long awns and weak straw. Red Bobs, on the other hand, resistant to bunt and loose smut, was awnless. According to the data obtained, he found no correlation between the awns factors and those for resistance and susceptibility. Johnston (31) in the genetic study of two varieties of barley (Glabrus x Trebi) found a slight correlation between factors for smut Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 12 infection and those for height of plants. He found, however, no linkage to exist between factors for covered smut reaction and those either for earliness of heading or barbing of awns. Giney and Tolman (68) in their study on the relationship between kernel color, glume color, and loose smut resistance of varieties of wheat, found no evidence of any relation­ ship between the morphological characters and resistance to loose smut (Ustilago tritici) . Schlehuber (59) stated that a possible leak linkage existed between smut-resistance to race I reaction and snike density, as well as between race I reaction and seed color in a cross between different varieties of wheat. Gfeller (18) reoorted the lack of linkage between factors of resist­ ance and those of awns in garnet wheat. Livingston (35) studied the rela­ tion between factors for resistance to Ustilago nuda and those for hoods or six-rowness in a cross between h'issouri Early Beardless x Hordeum deficiens. He stated that there was no linkage between the factors for resistance and those for hoods or six-rowness. Schaller (50) in his study on the inheritance of resistance to Ustilago nuda in barley, reported that no relation was found between factors for resistance and those for rough and smooth awns, black and white lemma and pericarp, two-rowed and six-rowed heads, hulled and naked seeds. E. Infection of Hybrid Progeny The infection of hybrids and Fg progeny is not investigated in the present work, and before discussing how the fungal hyphae become established after infection, it would be logical to discuss the penetra­ tion of infecting hyphae into the embryo. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 13 Freernan and JoVmson (17) investigated the life history of loose smut (Ustilago tritici) of wheat and that (Ustilago nuda) of barley using a susceptible variety of wheat (Minnesota 188) and a susceptible variety of barley (Minnesota 105). They inoculated the flowers of these varieties at different stages finding that the optimum time for maximum infection was from the time when the stamens ivere green to the time when the ovary was one third its natural size. After that stage the ovary wall and the aleurone layer would stop the penetration of the germ tube. Lang.(37) after investigating the penetration of smut hyphae in a susceptible variety of barley, stated two hypotheses through which the fungus might be able to reach the embryo. The first hypothesis was that the fungus reached the embryo by direct penetration through the ovary wall; the second was that the fungus reached the embryo through the stig­ ma tic tissues. Ruttle ($6) made some cytological studies on ovaries of Tennessee Winter barley which was resistant to the Featherston collection of Ustilago nuda. Her examinations showed that hyphae were within the pericarp. extent of penetration into the embryo was not deteimiined. The Livingston (3^) and Schaller (S8) found no infection occurring in F^ generation which indi­ cated that the genetic constitution of embryo tissues was heterozygous for resistance, and that this condition gave the embryo complete protection which enabled it to block the penetration of hyphae. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. lU MATERIALS AND METHODS In this investigation, four varieties of spring barley, provided by Dr. K, J. Frey of the Famn Crops Department, Michigan State College, were used, 1. Jet is a 2—rowed variety, with black kernels, of Abyssinian origin, and hulless. 2. Anoidiu'^ is a 6-rowed variety, with white kernels and flowering glumes, smooth awns and covered seeds. 3. Harlan is a 6-rowed variety, with white kernels and flowering glumes, semi-smooth and covered seeds. U* Ogalitsi is also a 6-rowed variety, with white kernels and flowering glumes, semi-smooth and covered seeds. All these varieties were tested for their reaction to the loose smut organism (Ustilago nuda (Jens.) K, and S., race I). The results V are recorded in Table 1, V. F. Tapke, at Beltsville, Maryland, also studied the reaction of Jet, Ogalitsu, Anoidium varieties of barley to Ustilago nuda race I. The results which he obtained (Table 2) were confirmed ty the author as shown in Table 1 in this study. The organism (Ustilago nuda (Jens.) K, and S., race I) was first supplied by Dr. V. F . Tapke* and maintained fresh on susceptible varieties in the green house and in the field. The four varieties were crossed into the six possible combinations, as f ollows: ^Senior Pathologist, U.S.D.A., B.P.I.S.A.E. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 15 Table 1. Reaction of Parental Varieties and o.A.C. 21 Inoculated Artificially with Ustilago nuda (Jens.) K. and S, race I Check Infected plants no. Row no. Inoculated plants obtained no. 6 22 0 0 17 0 0 Anoidium 16 192 0 0 U2 0 0 Ogalitsu 16 266 3 hi 0 0 5 hi 0 31 0 0 o .A .C .21 11 31 12 Variety Jet Harlan Table 2 Infected plants no. Infection pet. T, plant no. 1.12 0 Infectior pet. 38.70 Reaction of Some Varieties of Barley to Several Races of U. nuda (Jens.) K. ^nd S . Investigated by V. F. Tapke Varieties Ogalitsu Anoidium infec. pet. infec. pet. U . nuda race Jet infec. pet. 1 0 0 0 UO 2 0 0 9 6U 3 0 0 0 50 h 0 0 10 lU 5 0 0 0 88 7 0 0 0 67 8 0 0 0 25 ■«Unpublished data kindly furnished by Dr. V. P. Tapke. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Gold foil infec. pet. 16 1?50. 1, Jet X Harlan 2, Jet X Anoidium 3, Jet X Ogalitsu U. Harlan x Ogalitsu 5. Harlan x Anoidium 6, Ogalitsu X Anoidium Dr. K, J. Frey made thesecrossesat Michigan StateCollege in The seeds of the F]^ generation weregrownin 12-inch potsin the greenhouse in the fall of 19$0. In 19$1, the seeds of the Fg generation were space planted in rows 16 feet long and one foot apart. At the same time seeds inoculated with Ustilago nuda race I were sown in the field to secure fresh inoculum at the time of inoculation. To prevent the infection of the germinated infected seed with Ustilago nuda race I by the covered smut organism, the seeds were dusted with Cerasan before being planted. At blossoming time one or two heads were covered with cellophane bags before they emerged from the boots. renter of any natural infection. This was to prevent the occur— Similarly, the smutted heads on the stock plants were covered when they emerged. The preparation of teleutospore suspensions and the inoculation methods which were followed in this inves­ tigation were suggested by Poehlman fresh smutted heads were obtained from the smutted plants each day and chopped into small pieces and placed in a small piece of cheesecloth, and the spores were then submerged into a beaker containing a 1 percent dextrose solution in distilled water. When the solution turned a dark brown color, the teleutospore suspensions were filtered through clean cheesecloth to obtain a suspension free from foreign matter• Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 17 For inoculation a l^ypodermic needle (1 inch, 23 gau^e) with a syringe (13 cc. capacity) were used. The le^nma of each floret in the head was pierced without injuring the flower parts, and then one or two drops of the suspension were injected into each floret. The inoculations were made in one or two days after the head had broken the boot, because at this stage the majority of the florets of the head have already been pollinated. After the inoculation of each plant, cellophane bags were returned for enclosing the inoculated heads. Then each .inoculated head was tagged to be distinguished and kept separately at harvest time. At the end of the season, the labeled heads were harvested and kept seoarately in marked envelopes. Besides, one or two uninoculated heads of each Fg plant were harvested for linkage studies. The content of each envelope was threshed separately after the removal of some of the terminal and basal spikelets. Due to the failure of the pollination of the cross Ogalitsu x Anoidium, more than 200 F 2 seeds, which were obtained from K, J, Frey, were planted in 12-inch pots in the greenhouse in the fall of 1952. The inoculation procedure for this material was the same as already described. In the spring of 1952 (April 22) the F^ inoculated-seeds were planted in the field at the same time in rows four feet long, one foot apart. Every row containing the F^ seeds of each envelope represented one F 2 plant. They were designated by F^ family. Similarly, the F^ uninoculated seeds which represented the same Fg plants, were planted also in four foot long rows, one foot apart for studying the morphological characters. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CD ! Q. Table 3« - M strlb a tio n of C g progenies fo r loose snat infection gronped into 5 percent classes o. I Percentage classes i 0 0 5 5 10 10 15 15 20 25 30 35 40 20 25 30 35 40 45 M 50 Total number 50 55 55 60 60 65 65 70 75 80 85 90 95 70 75 80 85 90 95 100 C/) o' 0.A.C.21 3 O "8O 4 2 2 3 11 Jet 6 6 Earlan 5 5 Jet X Harlan 131 6 17 7 7 8 2 2 2 0 1 - — — — — — 1 1 0 1 186 6 6 Anoidiw 16 16 3 . 3 Jet X Anoidium 37 CD Jet Jet " CD ■D O Q. C a O 3 ■D O CD Q. ■D 1 1 1 43 6 15 0 0 Jet X Ogalitsu 12 0 1 16 1 13 5 5 Ogalitsu 15 0 0 1 % rlan x Ogalitsu 47 7 11 8 Harlan 1 6 Ogalitsu Harlan 2 16 4 3 2 1 0 2 85 5 5 16 16 CD Anoidium C/) C/) Harlan x Anoidium 102 Ogalitsu 15 Anoidium 16 Ogalitsu X Anoidium 122 9 18 12 0 I 0 18 10 10 8 7 2 7 3 6 4 2 6 3 1 3 1 0 232 16 16 0 4 8 8 6 3 2 0 2 3 158 CD 19 After germination of the planted seeds, the heavj’’ rows were thinned in such a way that all plants benefitted eaually from their environments. Before harvest time readings of the total infected and non-infected plants of each row were taken and recorded separately. If one tiller in a plant was infected, the whole plant was recorded susceptible. Jet differed from the other varieties in more than one morphological character. Therefore readings of the morphological segregation in each corresponding row of each cross, which included the Jet variety, were recorded [Tables A, B, C (Appendix)^ • Then the percentage of infection of each F ^ row which represented the F 2 plant was computed and recorded. Finally F 3 families were grouped into ^ percent classes (Table 3). Then they were classified as resistant, segregating, and susceptible according to the calculated percentage of each family [ Plate I, Tables A, B, C, D, E, F (Appendixfj" the F^ families. These classifications were based upon the behavior of The inheritance of the important morphological characters and the linkage relations between resistance and the morphological characters were also studied. Eleven rows of seeds inoculated with Ustilago nuda (Jens.) K, and S., race I, of the susceptible variety O.A.C. 21 were also planted to study the reaction of this variety to the disease. Before harvest time, the total of infected plants and the total of healthy plants was recorded. The percentage of infection for each row was computed as for the F^ families of the different crosses (Table G, Appendix). Then they were also grouped into 5 percent of infection classes (Table 3). Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. # 20 To study the characters of the teleutospores of the s^iutted beads in the families in comparison with those of the original Ustilago nuda (Jens.) K, and S., race I, samples of smutted heads of the were taken in the field and kept separately. families The laboratory rnicrocropic studies on the morphology of these teleutospores and those of the original ones were made. Similarly the germinations of the teleutospores of the selected smutted heads as well as those of the original teleutospores of Ustilago nuda (Jens.) K. and S., race I, were also observed and compared. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 21 EXTERBffSNTAL FŒSULTS A. Study on the Reaction of the Parental Varieties: Jet, Anoidium, Harlan, Ogalitsu to Loose Smut Infection The reaction of the parental varieties to loose smut infection was studied in the same field. The method used for plantinr, inoculating, and recording data were the same as previously explained in the chapter on Materials and Method (page lit) . However, according to the data in the Table 1, three parents. Jet, Anoidium and Harlan, showed a high resistance. Ogalitsu variety showed 1.12 percent of infection; it was also resistant. B, Study on the Inheritance of Resistance in Hybrids I 1. Jet X Harlan. The families were classified as resistant, segregating, or susceptible, and the demarcation line between segregating and susceptible progenies was more or less arbitrary. The reason for the arbitrary decision was the lack of a method of inoculation which gave 100 percent infection, because of the variation of the effectiveness of the inoculation method. O.A.C. 21, a variety susceptible to Ustilago nuda, race I, was used to estimate the percentage of infection which could be obtained. The . method of inoculation used in this experiment was the hypodermic needle method which was explained previously. The maximum- percentage of infec­ tion obtained was 38.70 percent (Table l) compared to UO percent (Table 2) in the gold foil variety obtained by V. F. Tapke, and the lowest per­ centage of infection obtained in a row was 33*33 percent (Table G, Appendix). Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 22 Therefore, the denaraction line chosen to show the classification of the progenies between segregating and susceptible was 30 percent. Even if this percentage were true, the whole conception would still be based upon assumption. Therefore, the progeny in which the percentage of infected individuals was more than 30 percent of infection were arbitrarily classi­ fied as susceptible (Table 3)» The segregating progeny were those in which the percentage of infected individuals was less than 30 percent. Finally, the resistant progeny wore those in which no infected plants were found, (but it must not be forgotten that some segregating progeny might have more than 30 percent and some of the susceptible progeny might show less than 30 percent of the plants infected). ing, the Generally speak­ families could be distinguished on the basis of the results obtained and' indicated in Table' B (Appendix) and summarized in Table h) . Table h. infection of Families Obtained from the F2 Plants Inoculated with Ustilago nuda, race I Cross Jet X Harlan Planted F2 progeny no. 195 Germinated F3 family no. 186* Total F3 infected plants. plants no. no. 2365 150 Number of infected F 3 families in percentage classes 0.0 0 .01-30 30.01-100 131 hi 8 * Nine F 3 families did not germinate. The foregoing table (ii) shows there were 131 families with 221^ individual plants which showed no smut disease, whereas 55 F^ families with 150 individual plants showed infection ranging from 0.01 percent to 100 per­ cent, The distribution of these families and those of the parents in Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 23 N = 186 70. U3 « •s I 0> CL. 12 - 0 2.2 Figure 1. 17.5 32.5 77.5 92.5 Percentage of loose smut infection Distribution of Rows of the Cross Jet x Harlan and the Parents into 5 Percent Infection Classes Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 2U ^ percent classes are given in Table 3 and they are shown graphically in Figure 1. According to the arbitrary line which was chosen as a limit between the segregating and susceptible progeny, the F ^ families were di­ vided into two groups. In the first group, a total of 3 F^ families con­ tained over 30 percent of infection. In the second group, 178 F ^ families contained less than 30 percent of infection. -Vithin those 1?8 families there were U? F-j families distributed between 0.01 t'> 30 percent of infec­ tion. These h7 F^ families included the segregating progeny. There­ fore, the 179 F^ families in the second group were considered to come from resistant Fg plants and the eight F 3 families, which came from susceptible F 2 plants were considered susceptible. The ratio of the two groups harmo­ nized with the expected ratio 10:1 if the resistant character in the progeny was governed by two genes. Table 0. Chi-square Test of the F^ Progeny of the Gross Jet X Harlan, Distributed in 0 Percent Classes Cross Jet X Harlan Ustilago nuda race Char­ acter Observed fre­ quencies no. Res. 178 Sus . 8 Theo­ retical ratio Calculated frequencies no. - Probability range 17k.3 1 l$tl 11.62 1.129 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 0 .30-0.20 22 92 N = U3 86, OU 72 62 I ^22 cr\ % li2 % |35 I #) PL, 12 J 0 2,^ Figure 2. 17.2 !___ !___ L JL J L 32.2 U7.2 62.2 77.2 Percentage or loose smut infection J I I I J L L 92.2 Distribution of Fg Roes of the Gross Jet x Anoidium and the Parents into 2 Percent Infection Classes Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 26 The chi-square was l,l2o and the probability range was b.30-0.20. Therefore, the chi-square value (Table indicated that the resistant character in the hybrids of the cross. Jet x Harlan, was controlled by two genes in 'which they were acting in a duplicate dominant condition of enistasis. These two genes were independent. Since segregation occurred (Table 3) between the two genes, they were different. ViTith two independent genes l/l6 of the total Fg progeny was completely susceptible. number of ■ 11.62, The exoected families which should be completely susceptible is l86 x l/l6 But the observed number of the completely susceptible F2 plants was 8 , This number was withiri the range of the expected susceptible 3 families for independent factor inheritance. 2. Jet X Anoidium. The study of inheritance of resistance to Ustilago nuda (Jens.) K . and S., race I, in the hybrids of the cross Jet x Anoidium was accomplished in the same manner and under the same conditions as for the hybrids in the cross Jet x Harlan. In the F2 generation a total of only U3 F2 plants were available in this cross. recorded in Table A (Appendix). Data were observed and The distribution of F^ families into ^ percent infection classes is given in Table 3 and is shown graphically in Figure 2. Because the number of families was very small, it was difficult to study the behavior of the resistant factor in the hybrids. .The direction of the curve in Figure 2 indicates to a certain extent, however, that if the number of families was large enough, it would follow the same direc­ tion as the curve in Figure 1. The curve in Figure 1 was that of the hybrids which possessed two factor pairs for the resistant character. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 27 N = 13 92 .30 I 7^ CU) o K «H 65 o % Daane (11) and Griffee (20) the characters two-rowed versus six-rowed segregated in a Mendelian ratio in wliich two-rowed is dominant over sixrowed heads. This segregation was confirmed in this investigation. Data of the segregations in the F 2 generation were taken from the Fg plants which were grouped on the basis of the behavior of the F^ families in the cross of Jet X Harlan, All plants of F^ generation were two-rowed heads. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This 38 information indicated that the two-rowed character is dominant over the six-rowed character. In the F 2 generation, I86 F 2 plants were observed and the data were recorded and anlyzed in Table 12. Table 12, One hundred and forty-six F 2 Segregation of Two-rowed vs. Six-rowed Heads in Barley Hybrids of 2—row no. Observed Theoretical 3:1 the Cross Jet x Harlan 6-row no. 1U6 UO 139.5 U6.5 X2 P 1,20 0 .30-0.20 of the 186 F 2 plants were classified as two-rowed head, and Uo as six-rowed heads. The ratio obtained agreed with the expected ratio 3:1. was 1.20. The probability range was 0.30-0.20. Chi-square This information indicated that the segregation was controlled by one factor pair and that the tworowed character was dominant. In the cross Jet x Anoidium all the plants of two-rowed heads. generation were also The segregations in F 2 generation are analyzed in Table 13. Of U3 F2 plants twenty-six plants were classified as two-rowed heads and 1? as six-rowed heads. The ratio observed agreed with the expected ratio 3:1. The chi-square was U.3U. The probability range was 0,05-0.02. These data indicated that the segregation was controlled by one factor pair and that the two-row character was dominant. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 39 Table 13. Segregation of Two-rowed Heads vs. Six-rowed Heads in Barley Hybrids of the Cross Jet x Anoidium Observed Theoretical 3:1 2-row no. 6-row no. 26 17 32.25 10.75 In the cross Jet x Ogalitsu all the x2 U.8U . P 0.05-0.02 plants were two-rowed heads The analysis of data in F^ generation (Table lU) showed that of 13 F2 plants 10 plants were tyro-rowed heads and 3 plants were six-rowed heads Table lU. F2 Segregation of Two-ro?æd Heads vs. Six-ro^ved Heads in Barley Hybrids of the Gross Jet x Ogalitsu 2-row no. Observed Theoretical 3:1 10 9 .7 2 6-row no. P X2 3 3.25 0.025 The ratio observed agreed with the expected ratio 3:1. was 0 .025, The probability range was 0.90-0.80. 0 .00-0.80 The chi-square These figures indicated that this segregation was controlled by one factor pair, and that the two-row character was dominant. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Uo 2. Fulled versus naked seeds. According to Daane (11), Robertson (U9 and Biffen the difference between the characters hulled and naked were based upon a single factor pair: hulled being dominant over naked. The results of the present investigation agree. In the cross Jet x Harlan all plants of generation had hulled seeds. The data of the segregations in F 2 generation were analyzed (Table 1^). One hundred and twenty-seven of the 186 F2 plants were Table 1^. F2 Segregation of Hulled vs. Naked Seeds in Barley %-brids of the Cross Jet x Harlan Hulled no. • Observed Theoretical 3:1 Naked no. 127 $1 137.2$ U$.2$ P 3.061 0.10-0.0$ classified hulled seeds and ^1 plants were classified naked seeds. ratio observed agreed with the expected ratio 3:1. 3 .061. The probability range was 0.10-0.0Î?. The The chi-square was This information indicates that there is one gene difference between the two characters: the hulled character was dominant. Similar results obtained when Jet was crossed with Anoidium. All plants of F2 generation had hulled seeds, indication that the hulled char­ acter was dominant over naked character. The analysis of the data (Table I6) showed that of the Ul F2 plants, 2? plants were classified as hulled seeds and lU as naked seeds. The ratio observed harmonized with the esq^ected Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ill Table 16. F g Segregation of Hulled Seeds vs. 1-aked Seeds in Barley Hybrids of the Cross Jet x Anoidium Hulled no. Observed 27 Theoretical 3:1 ratio 3:1. Naked no « P lli 30.7$ 10.2$ The chi-square was 1.828, 1.828 0.20-0.10 The probability range was 0.2-0.1, indicating that the segregation was governed by a single gene. In the cross Jet x Ogalitsu, the results shown in Table 17 indicated that the segregation was controlled by a single gene: hulled character was dominant. Table 17. Fg Segregation of Hulled Seeds vs. Naked Seeds in Barley Hybrids of, the Cross Jet x Ogalitsu Hulled no. Observed Theoretical 3:1 3. 12 9.7$ Naked no. P 1 3.2$ Rough awns versus smooth awns. 2.07 0.20-0.10 Griffee (21), Robertson (29), and others found the difference between rough awn character and smooth awn character was based upon a single factor pair, and that the character rough was dominant over smooth. In the cross Jet x Anoidium all plants of Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U2 F2 generation had rough avms. are analyzed in Table 18, Table 18. Data of the segregation in F2 generation Twenty-eight Fg plants were classified as rough F^ Segregation of Rough Awns vs. Smooth Awns in Barley Hybrids of the Cross Jet x Anoidium Rough awns no. Observed Theoretical 3:1 28 lU 31.5 10.5 awns and lU as smooth awns. ratio 3:1. Smooth awns no. 0 .30-0.20 1.S78 The observed ratio agreed with the expected The chi-square was 1.578. The probability range was 0.30-0.20, indicating that the segregation was controlled by one factor pair: rough character was dominant. In the cross Jet x Ogalitsu, all F^ plants had rough awns. The chi- square value O.6LO (Table 19) which gave a probability 0.50-0.30, showed a good fit for one single gene governing the awn character. Rough character was dominant. Table 19. F 2 Segregation of Rough Awns vs. Smooth Awns in Barley Hybrids of the Cross Jet x Ogalitsu Rough awns no. Observed ' Theoretical 3:1 11 9.75 Smooth awns no. X2 P 2 3.25 O.6UO 0 .50-0.30 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ii3 U> Black lem^a and pericarp vs. white le^nma and pericarp. Biffen (5), Robertson (1*9) ,and Schaller (58) found one single gene difference occurred between black and white lenma. Biffen (5) and W^oodward (73) found also that the black and white color of lemma was associated with the black and white pericarp. The results of this investigation agreed. Harlan all In the cross Jet x plants possessed black lemma and pericarp. The segregations in F 2 generation were observed and recorded (Table B, Appendix). Data were analyzed in Table 20. Table 20. F 2 Segregation of Black and White Color of Lemma and Pericarp in Barley Hybrids of the Cross Jet x Harlan • Observed Theoretical 3:1 Black lemma and pericarp no. White lemma and pericarp no. lUh Ul 138.7k U6.25 P 0.793 0 .50-0.30 Of 185 F 2 plants there were lUh plants which were classified as black lemma and pericarp and Ll plants as white lemma and pericarp. ratio agreed with the eaqpected 3:1 ratio. the probability range was 0.50-0.30. The observed The chi-square was 0.793, and The segregation was apparently con­ trolled by one factor pair, and the black character was dominant. In the cross Jet x Anoidium the F^ plants were all black lemma and pericarp. The segregations in F_ generation were analyzed in Table 21. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UL) Table 21. F2 Segregation of Black Lemma and Pericarp vs. White Lemma and Pericarp in Barley Hybrids of the Cross Jet x Anoidium Black lemma and pericarp no Observed White lemma and pericarp no. 3U Theoretical 3:1 32.25 0 y. p 9 0.378 10.75 0 .70-0.50 Thirty-four of the L3 Fg plants were classified as black lemma and pericarp, and 9 as white lemma and pericarp. The probability range was 0.70-0.50. The chi-square was 0.378. The results indicate that segrega­ tion was controlled by one factor pair, and that black character was dominant. Similar results in the F^ generation and Fg generation were found in the cross Jet x Ogalitsu. The data of the segregations in Fg generation were analyzed (Table 22). Table 22. Fg Segregation of Black Lemma and Pericarp vs. White Lemma and Pericarp in Barley Hybrids of the Cross Jet x Ogalitsu Black lemma and pericarp no. Observed Theoretical 3:1 11 9.75 IVhite lemma and pericarp no. p 2 3.25 0 .6U0 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 0.50—0.30 U5 The chi-square was O.6UO. The probability range was 0.SÙ-0.30, indicating that one single factor pair was involved. Black character was dominant• D, Study of the Linkage Relations Since one ofthe parents (Jet) was different from the other in more than one morphological character, it was desirable to study the relation between the resistance and these morphological characters. The hybrids of the cross Jet x Harlan were used for the study, 1. Resistance vs. susceptibility with two-row vs. six-row heads. According to the results obtained in this paper (page 22) the resistance character in hybrids of the cross Jet x Harlan was controlled by two factor pairs acting in duplicate dominant condition of epistasis. has been shown (Table 12) that' the character controlled by one gene. It two-row vs. six-row was Therefore, the data for the segregation of these characters were recorded and analyzed in Table 23, Table 23. F 2 Segregation of Resistant vs. Susceptible with Two-row vs. Six-row Resistant Six-row Two-row no • no. Susceptible Two-row S ix-row no. no. Observed 139 39 6 1 Theoretical (1$:1)(3:1) 130 U3.35 8.67 2.89 Chi-square = 6.6U Probability range = 0.10-0.0$ Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U6 From this classification, the poodness of fit for independence was computed by the chi-square method. probability range was 0.10-0.0^. fit for independence. The chi-square was 6.6h, and the The chi-square value indicated a good Therefore, according to the data collected in this study, there was no linkage between the factors controlling the resistance or the susceptibility and those controlling two-row and six-row heads. 2. Resistance vs. susceptibility with hulled vs. naked seeds. The segregations for the above mentioned characters in Fg generation were analyzed in Table 2U. Table 2U. Fg Segregation of Resistance vs. Susceptibility with Hulled vs. Naked Seeds Resistant Hulled Naked no. no. Observed 122 Theoretical (I5:l)(3îl) 128.25 U2.75 Susceptible Hulled Naked no • no. 6 1 8.52 2.85 Chi-square » 5.22L Probability range = 0.20-0.10 This classification consisted of 122 F2 plants hulled resistant; 5U F 2 plants, naked, resistant; six F2 plants, hulled, susceptible; and one F2 plant, naked, susceptible. The chi-square was 5.22U. The probability range was 0.20-0.10, indicating a good fit for independence. Therefore, resistance, susceptibility, hulled and naked character of seeds were independently inherited. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U7 3« Resistance vs. susceptibility with black lemma and pericarp vs white lentma and pericarp. The data on the segregations of the above mentioned characters were recorded and analyzed in Table 2$. Table 25. F2 Segregation of Resistance vs. Susceptibility with Black Lemna and Pericarp vs. White Lemma and Pericarp Resistant Black lemma White lemma and pericarp and pericarp no. no. Susceptible White lemma Black lemma and pericarp and pericarp no. no » Observed lUO 38 U 3 Theoretical (15:1)(3:1) 130.05 L3.35 8.67 2.89 Chi-square = 3.9U5 Probability range = 0.30-0.20 The classification consisted of ihO F2 plants, resistant, black lemma and pericarp; 38 F2 plants, resistant, white lemma and pericarp; U plants, susceptible, black lemma and pericarp; 3 Fg plants, susceptible, white lemma and pericarp. was 0.30-0,20, The chi-square was 3.9L5 and the probability range This value indicated that there was no linkage between the factors controlling the resistance or the susceptibility and those con­ trolling black and white lemma and pericarp. The following table (26) contains the summary of the results of the chi-square tests of all characters which were included in the hybrids of the crosses used in the present study. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U8 Table 26. 2 Summary of X Tests for Mode of Inheritance and Linkage Relations of Characters in the Various Crosses Studied in this Paper Crosses and Characters Ratio Chi-square D.P . Probability Observations Jet X Harlan (N = 186) 2-row vs. 6-row heads (Vv) Hulled vs. naked seeds (Nn) Black vs. white lemma and pericarp (Bb) 3:1 1.20 1 0.30-0.20 2-row dominant 3:1 3.061 1 0.10-0,00 Hulled dominant 3:1 0.793 1 0.00-0.30 Black dominant 1^:1 3:1 15:1 3:1 15:1 3:1 3.111 3 0.00-0.30 Independent 5.22U 3 0.20-0.10 Independent 3.9U5 3 0.30-0.20 Independent Resistant vs. susceptible in relation to: 2-row vs. 6-row Hulled vs. naked Black vs. white lemma and pericarp Jet X Anoidium (N = li3) 2-row vs. 6-row heads 3:1 U.8U 1 0.00-0.02 2-row dominant Hulled vs. naked seeds 3:1 1.628 1 0.20-0.10 Hulled dominant Rough vs. smooth awns 3:1 1.578 1 0.30-0.20 Rough dominant Black v s . white lemma and pericarp 3:1 0.378 1 0.70-0.00 Black dominant 2-row vs. 6-row heads 3:1 0.020 1 0.90-0.30 2-row dominant Hulled vs. naked seeds 3:1 2.07 1 0.20-0.10 Hulled dominant Rough vs. smooth awns 3:1 0.6U0 1 0.00-0.30 Rough dominant Black vs. white lemma and pericarp 3:1 0.6U0 1 0.00-0.30 Black dominant Jet X Ogalitsu (N = 13) Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. h9 SELECTION Because the hybrids possessed a very valuable character (resistant to loose s^ut disease), a selection program was taken into consideration. The family rcrirs which did not show any infection were selected to be used for further research work. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. so DISCUSSION The study of the inheritance of resistance is complicated because of several important factors. For instance, the lack of an inoculation method to pive one hundred percent infection does not allow the researcher in this field to make a definite separation between serrr^natinr and sus­ ceptible progenies. A demarcation line must be based upon an assumption. Another complicating factor is the presence of many physiologic forms of Ustilago nuda within the species and the occurrence of continual hybridi­ zation between these forms and between different species, providing- new forms which may be present in the natural inoculum. were eliminated by using a specific race I. New form, however, The microscopic study of the morphology of teleutospores, which were collected from the progenies and that of their germination manner, in comparison to those of the orig­ inal race I showed a great similarity. In this thesis the study of the genetic constitution of the F« population of six crosses of barley was based upon the classifications of the families. In the cross Jet x Harlan the observed ratio indicated the presence of two genes controlling the resistant characters. The occurrence of eight susceptible F^ families in this cross indicated that these genes for resistance in Jet and Harlan were different. value showed they were inherited independently. Moreover, the chi-square The number of F^ rows planted was 1*^5, and the number of germinated F^ rows was 186 with nine F^ families failing to emerge. Several factors could cause this failure. One, already mentioned by Thren (67), was due to the invasion of the embryo Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 51 tissues by the f u n ^ s . If J represented the factor for resistance in Jet and H that of Harlan, the genetic constitution of the oarental varieties would be JJhh for Jet and HF.jj for Harlan. In the crosses Jet x Anoidium and Jet x Ogalitsu, the number of families was inadequate to allow any accurate genetical studies. In com­ paring the graphs of the cross Jet x Anoidium with that of Jet x Harlan (Fig, 7) it seed’s that if the curve of the former cross was more extended, it would follow the same direction as that of the latter cross. In other words, the data might show two factors governing the resistance in the progeny. . The data on the cross Harlan x Ogalitsu explained satisfactorily the fit for two factor pairs controlling the resistance in the progenies. These factors which acted in a duplicate dominant epistatic condition were different and independent. Each factor pair was obtained from one parent. If 0 represented the factor for resistance in Ogalitsu, the genetic consti­ tution of the latter would be 00hh. The segregation of F^ families in the cross Harlan x Anoidium agreed with the ratio when two different factor pairs were involved, independence. ^^oreovor, the chi-square value also indicated their This observed ratio harmonized with the theoretical ratio 13:3 which indicated the occurrence of two genes acting in dominant and recessive condition of epistasis. According to Tables 2 and 26 the characters for resistance in Harlan and Anoidium were controlled by one dominant gene. The expected ratio, therefore, between resistance and susceptibility in the progeny of the discussed cross should be l5:l. The presence of "three susceptible families might be interpreted by the presence of fluctuation in some of the nine following genotypes of Fg progeny: HHAA, HHAa, HHaa, HhAA, HhAa, Hhaa, hhAA, hhAa, hhaa. types HHAA, HHAa, HHaa, HhAa, hhAA were resistant. The probable Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The geno­ occurrence of fluctuation was suggested to be in the genotypes Hhaa; hhAa, in ^hich one gene for resistance was in the heterozygous condition while the other was in the recessive condition. The caure of this fluctu­ ation is not known, but it may be due to a change of the expression of the resistance and susceptible which, might be influenced by the environments. In T a b l e . t h e total of families planted was 23h, of'which only 232 F. families germinated. The failure of germination of these F j . 3 families could be attributed to the same reason which was discussed above. The genetical study in the cross Ogalitsu x Anoidium indicated the occurrence of two factor pairs in the progenies acting in duplicate dominant epistatic condition. varieties was then: The genetic constitution of the parental OOaa'for Lgalitsu; AAoo for Anoidium, were different and independent in their inheritance. These genes The failure of germination of the eight families (Table 10) may be explained as in the case of the cross Jet x Harlan. Livingston (35) found the same dominant gene controlling the resistance in Trebi and Hordium deficiens. Schaller (58) reported four different dominant genes for the resistance in the resistant varieties he used. In this study four dominant genes were also found to be located in the resist­ ant varieties. These genes were different and independently inherited. Three of them were not reported. Robertson, Wiebe and Shand (50) and Robertson, Wiebe, and Immer (5l) recommended the use of the following symbols for three different dominant genes. They recommended Un^ for the gene in Jet; Un^ for that in Dorsett; Unç for the gene in the selection X173-10-1^-61. It may be suggested the symbols Un^, Uriy, Ung for the genes respectively in Harlan, Anoidium and Ogalitsu. Reproduced with permission of the copyright owner. Further reproduction prohibited without permlssioh. S3 Because Jet differed from the other varieties in more than one agronomical character, the study of the inheritance of these agronomical characters in the progeny of the cross in which Jet was involved was desirable. In the cross Jet x Harlan, Jet x Anoidium, one gene difference was found between; and Jet x Ogalitsu, two-rowed vs. six-rowed heads, hulled vs. naked seeds, rough vs. smooth awns, black vs. white le^^a and pericarp. The factors pairs for two-rowed, hulled and black lemma and pericarp were dominant over those for six-rowed, naked and white lemma and pericarp. These results confirmed those stated by previous investigators (?, 11, 21, U9, S8, 73). In the cross Jet x Anoidium, the chi-square for two—rowed vs. sixrowed heads was U.8U. This value showed a fair fit for the occurrence of one gene difference between these characters. due to the inadequate number of The reason might be progenies in the rows in genera­ tion, which did not allow a complete segregation. The study of the relations between resistance and morphological characters of the parental varieites was accomplished in the cross Jet x Harlan. The results reported in Tables 23, 2h and 2$ showed that there was no linkage occurring between factors for resistance and those for two-rowed vs. six-rowed heads, for hulled vs. naked seeds, for black vs, white lemma and pericarp. The resistant varieties Jet, Anoidium, Harlan and Ogalitsu are not recommended for commercial use. Also the commercial varieties are known to be susceptible to loose smut infection. Therefore, further breeding work would be valuable for introducing the factors for resistance into the desired varieties in a specific region. On the other hand, the lack of a Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 2L method by which it is possible to obtain one hundred percent infection allows the segregating progenies to occur among the homozygous ones for resistance. For this reason, the continuation of varietal reaction tests to Ustilago nuda (Jens.) K. and S., race I, for several generations will be necessary to secure the homozygous progenies for resistance. Another point which appears to be important is that Schaller (58) and the author found different genes controlling the resistance in different varieties. Furthermore, these genes are located on different chromosomes. It would be more desirable to have progenies whose genetic constitution is made up of different factor pairs from different sources for resistance. When these characteristics are obtained in the progenies, a breeding program between the resistant progenies and the commercial varieites will be very valuable• Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 55 Sm-1TITARY 1. Ustilago nuda (Jens.) K, and S., race I, was the causal organise of loose smut disease in this study. The varieties of barley which used as parents were Jet, Anoidium, Harlan, Oc^alitsu, were The infection reaction of these varieties showed that they were highly resistant to the disease. 2. The families which represented the Fg plants were classified according to their percentages of infection, resistant, segregating and susceptible. The demarcation line between the segregating and susceptible F ^ families was abritrarily assumed, possibly attributable to failure to use a method which gives one hundred percent infection. 3* In the crosses Jet x Harlan, Harlan x Anoidium, Harlan x Ogalitsu, and Ogalitsu x Anoidium, the resistant character appeared to be con­ trolled by two factor pairs acting in a duplicate dominant condition of epistasis. The chi-square test showed that these factors were independently inherited, and their segregation in the Fg generation proved that they were different. Consequently, it is possible to say that resistant character in each parental variety was controlled by one dominant gene; but the four genes, however, were different. ii# The genes for resistance in Anoidium, Harlan, Oralitsu were not reported before. The use of the following symbols; Un^, Un^, Ung for the genes respectively in Harlan, Anoidium and Ogalitsu was recommended. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 56 The chi-square test showed that there ;vas one %ene difference between the following morphological characters; two—rowed vs. six-rowed heads; hulled vs. naked seeds; rough vs. smooth awns; black vs. white lemma and pericarp, in the crosses Jet x Harlan, Jet X Anoidiumj Jet x Ogalitsu. 6. There was no evidence for linkage between the factors for resistance and those for two-rowed vs. six-rowed heads; for hulled vs, naked seeds, and for black vs. white le^ma and pericarp. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 57 LITERATURE CITED 1, Agricultural Statistics# U.S.D.A. Government Printing Office, ashing ton, 1951. 2, Alexopoulos, C . J ., Introductory Mycology. John Wiley and Sons, Inc. New York, Chapman and Hall, Ltd., London, 1952. 3, Bessey, E, A., Morphology and Taxonomy of Fungi. Philadelphia, Toronto, 1950. U. Biffen, R. H,, Mendel's lavrs of inheritance and wheat breeding. Agr. Sci,, 1; U.U8, 1905. 5. __________ , The hybridization of barleys. 206, 1907. 6. Bref eld, 0. 7. The Blakiston Co., Jour. Jour. Agr. Sci., 2; 183- Botanische Untersuchungen fiber Hefenpilze De Brand pilze, I. 1883. , Neue Untersuchungen und Ergebnisse fiber die nattirliche Infektion und Verbreitung der Brandkrankheiten des Getreides. Nachrichten aus demklub der Lnadwirthe zu Berlin, h66zh22h-h23h, 1903. 8. Buckley, G. F . H., Inheritance in barley with special reference to the color of caryopsis and lemma. Sci. Agr., 10; U60-h92, 1930. O. Butler, E. J,, and S. G. Jones, Plant Pathology. Ltd., London, 19U9. Macmillan and Co., 10. Crop Production, Crop reporting board Bureau of Agricultural Economics, U.S.D.A., 1952 annual summary, 1952. 11. Daane, A., Linkage relations in barley. Bui, 78, 1931. 12. David, P. A., A study of crosses between Trebi and three smooth-awned varieties of barley. Iowa State College, Jour. Sci., 285-31U, 1931 13. Dickson, J. G., Diseases of Field Crons. Inc., New York and London. lU. Minn. Agr. Exp. Sta. Tech. McGraw-Hill Book Company, Dittmar in Shurm, Deutschlands Flora, 3, p. 67, t. 33, 1815. 15. Dodoens, R., A niewe Herball, 1578. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ^8 16. Engledow, E, L,, Inheritance in barley. I. The lateral florets and. the rachilla. Jour. Gen., 10: 93-108, 1920. 17. Freeman, S. M., and E. C. Johnson, The loose smuts of barley and wheat. U. S. Dept. Agr. Bur. PI. Ind. Bull., 152: 1-U3, 1909. 18. Gfeller, F ., Inheritance of earliness of heading and other characters in a Garnet x Red Fife cross. Sci. Agr., 17: L82-h91, 1937. 19. Gillis, M . C., A genetical study of fertility of the lateral florets of the barley spike. Jour. Apr. Res., 32: 367-3^0, 1926. 20. Goffman, F. A., et ^1., Inheritance of resistance in oats to Ustilago levis. Jour. Apr. Res., U3: lOGS-lO^o, 1931. 21. Griffee, F ., Correlated inheritance of botanical characters in barley and manner of reaction to Helminthosoorium sativum. Jour. Agr. Res., 30: 915-935, 1 9 ^ 22. Harlan, H. V., Smooth awned barleys. 205-208, 1020. Jour. Amer. Soc. Apron., 12: 23. __________ , Barley; Culture, uses and varieties. Bull. no. IU6U, 1^25. 2li. U.S.D.A. Farmer's , and H. K. Hayes, Occurrence of the fixed intermediate Hordeum indermidium haxtoni in cross between H. vulgare païïidum and H. distichon palmella. Jour. Agr. Res., 19: 575-591'; 1920T ------------------ 25. Hayes, ,H. K ., and R. J. Garber. Breeding Crop Plants. McGraw-Hill Book Co., Ed. 2, 1927. 26. ■ Heald, F . D ., Manual of Plant Diseases. New York and London, 1933. New York, McGraw-Hill Book Co., Inc. 27. Hitchcock, A. S., and M. A. Carleton, Second report on rusts of grain. Kans. Agr. Exp. Sta. Bull., U6: 9 pp., l89h. 28. Hor, K . S., Interrelations of genetic factors in barley. 9; 151-130, 192b. 29. Jensen, J. L., The oropogation and prevention of s™ut in oats and barley. Jour. Roy. Agr. Soc. England, 2U2: 39?-Iil5, 1888(b). 30. Jessen, C ., Sanenkatalog des eldenaer botanischen parten. Genetics, 1855, 31. Johnston, W. H., Studies on the dehulling of barley kernels with and on the inheritance of reaction to covered smut, Ustilago hord$i fPers.) K. And S . Infection in crosses between Glabron and Trebi barley. Cana. Jour. Res,, 11: U58-U73, 193b. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ?9 32, Kellerman, Vf. A., and \V. T. Swingle. Report on the loose s^ut of cereals. Kans. Agr. Expt. Sta. Ann. Reb., 2; (1889): 213-288, 1890. 33. Kilduff,T., Inheritance of bunt and loose smut reaction and of certain other characters in Kota and Red Bobs and Garnet crosses. Can. Jour. Res., 8: 1U7-172, 1933. 3hm Leukel, R. 7/., Factors affecting the development of loose smut in barley and its control by dust-fungicides. U.S.D.A. Tech. Bull. 2 9 3 , 1932. 35. Livingston, J . E., The inheritance of resistance to Ustilago nuda (Jens.) K. and S . in barley. Rhytopath., 32: ' l ^ h 2 . 36. LoSel, Matthias de., Plantarum sevstirpium icones, IS8I. 37. Lang, 7f., Zur Ansteckung des gerste durch Ustilago nuda. Deutsche, d. Bot. Ges., 3$: h-201, 19l7. 38. Maddox, F ., Experiments at Eastfield, smut, bunt, rust. Agr. Dept. Rent., 1895* 39. Michigan Agricultural Statistics, 1951. (B.A.I.) Ber. Tasmania. Michigan Dept, of Agriculture liO. Moore, M . B ., A partial vacuum method for the inoculation of wheat and barley with loose smuts. Phytopath., 26; 103, lh36. Ul. Nahmmacher, J ., Beitragzur Immunitaszuchtung der gerste gegen Ustilago nuda forma spec, hordei. Phytopath. Ztschr. -----UT- ' 5 9 7 - 6 3 ^ i 9 3 ? T U2. Neatby, K. 77., Inheritance of quantitative and other characters in barley cross. Sci. Agr., 7: 77-OU. 1926. U3. Persoon, C. R., Synopsis methodica fungorum I. I8OI. UU. Plinus Secundus, G ., Naturalis His.toriae (Translation by John Bostock and T. Riley, U, I89O). U5. Poehlman, J. T^., A simple method of inoculating barley with loose smut. Phytopath, 3$: 6U0-61ih, 19U5. U6. Powers, LeRoy, The nature of the interaction of genes affecting four quantitative characters in a cross between Hordeum deficiens and Hordeum vulgare. Genetics, 21: 398-U20, I936. U?. Prévost, J. B ., Mémoire surla cause immediate de la carie on charbon des blés, I807. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 60 U8. Reed, G. U?. Robertson, D. '.7., Linkage studies in barley. 50, Robertson, D. .7., G. A. iViebe and R. G . Shands, A sumriary of linkage studies in barley: Supplement I, I9UO-I9I46. Jour. Amer. Soc. Agron., 39: U6h-li73, 19h7. 51. Physiologic specialization of parasitic fungi. Bot. Gard. Mem., 1: 3U8-U09, 1918. Genetics, lU: Brooklyn 1-36, 1929, ,G . A. IViebe, and F. R. Immer. A summary of linkage studies in barley. Jour. Amer. Soc. Agron., 33: h7-6li, I9UI. 52, Rodenhiser, H. A., Physiologic for^s of Ustilago nuda and Ustilago tritici. Phytopath., 16: IOOI-IOO7, 1^26, 53. SU. ,Physiologicspecialization path., 18: 9SS-1003, 1928. in some cereal smuts. Phyt , and S. 0. Stakman, The control of loose smuts of wheat and barley and barley stripe by Uspulum, Sernasan and Germisan. Phytopath., iS: Si, 192S. 55. Russell, R. C ., Studies on the hot water method of treating seed barley for the control of true loose smut Ustilago nuda. Can. Phytopath. Soc. Proc., 19U7: lU-lS* 56. Ruttle, Mabel L. (Mrs. Nebel), Studies on barley smuts and loose smut of wheat. IJ.Y. Geneva Aor. Exo. Sta. Tech. Bui., 221, 193U. 57. Schaffer, L. A., and S, D. Hansing, Effect of hot water treatment on emergence of spring barley and control of brown loose smut. Phytopath., Uo, iS pp., S18-S21, 19S0, 58. Schaller, C. ’.V., The inheritance of resistance to loose smut, Ustilago nuda, in barley. Phytopath., 39: 9^9-979, 19U9. 59. Schlehuber, A. M ’Vheat inheritance: Reaction to four bunt biotyoes, soike density and seed color. iVash. Agr. Exp. Sta. Bull., 323, 1935. 60 . Schroeter, J., Zur entwicklungsgeschichte der uredineen. Gahrsber d. Schles. Ges. f. Vaterl. Cult. (Bot. sect.), 71: 31,32, 1893. 61 . 62. , Entwicklungschichte einiger rostpilze II, III, Cohn’s BeitrSge zur Biologie der Pflanzen, 3: 51-93, 1879. Semeniuk, W., and J. G. Ross, Relation of loose smut to yield of barley. Can. Jour. Res, (c) 20: U91-500, 19U2, Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 6l 63. Shand, H, L., and C, .V. Schaller, Response of spring barley varieties for floral loose s"iut inoculation. Phytopath,, 36: $3hSk8, I9li6. 61i, Sigffusson, S, J,, Correlated inheritance of glume colour, barbing of aivns and length of rachilla hairs in barley. Sci. Agr., 9: 662-67L, 1929. 65» S talonan, E. C ., Spore germinations of cereal smuts. Sta. Bull., 1 3 3 , 1913. 66. Tedin, H. and 0. Tedin, Contributions to the genetics of barley. I, Type of spike, makedness and height of plants, Hereditas, 7: 151-160, 1926. T^inn. Agr. Expt, 67. Thren, R ., Kritiche versuche zur resis tenzpriifung der gerste gegen flugbrand (Ustilago nuda (Jens.) K . and S.). Kühn. Archiv., UU: 211-231, 1930, 68. Tingey, D. C ,, and B. Tolman, Inheritance of resistance to loose smut in certain wheat crosses. Jour, Agr. Res., I4B; 631-656, 193b. 60 . Tulasne, I., R,, and Ch, Tulasne, h^moire sur les Ustilagine'e comparées aux Uredin^es. Ann, Sci, Nat, Bot. III., 7: 12-127, 18U7* , __________, Second mémoire sur les Uridinées et les Ustilaginées. Ann. Sci. Nat. Bot, IV., 2: 77-196, l85U. 70. 71. Tyner, L, S,, and R, C, Russell, Report control of barley loose smut by spergon S,L, Plant Disease Reporter, U.S.D.A. Bur. PI. Ind., 36, no. 5, 1952, 72. Ubisch,G. von, Beitrog zueiner faktorenanalyse von gerste. Ztschr. Induktive, Abstramrn. u. Vererbungslehre, 17: 120-152, 1917. 73. .Voodward, 7b. R, ’V., Inheritance of a melaninlike pigment in the glumes and caryopses of barley. Jour-. Agr. Res,, 63: 21-28, I9UI, Zeiner, Vf,, Das verhalten vsrschiedener sommer gersten kreuzungen hinsichtlich der anf&lligkeit ftir Ustilago nuda, Ztschr, Zuchtung,, A, 17: 229-26b, 1932. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 62 APPENDIX Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 63 B P la te 1 . shows t y p i c a l r e a c tio n o f h y b rid progeny to in o c u la tio n w i t h p d t lla g o nuda ra c e I . A. B. C• S u s c e p tib le (m id d le row) S e g re g a tin g R e s is ta n t Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 6U The symbols used in the following tables were suggested by Robertson, Wiebe and Immer (^1) to designate the morphological characteristics of the heads of the progeny of each genotype. Table A. Percentages of Infection of Families. Morphological Charac­ teristics of F 2 Plants Based upon the Behavior of F^ Families of the Cross Jet x Anoidium '3 rows number 23001 2 3 h 5 6 7 8 9 10 11 12 13 lU 1^ 16 17 18 19 20 21 22 23 2h 2$ 26 27 28 29 30 Inoculated Head characteristics of Fg plants pits. obtained Infection 2—rowed or Rough or Covered Black To^aT" ïn^ectëd pet. smooth or naked white ! 6-rowed lemma number number and pe: 12 21 11 . 28 22 8 1^ 32 8 18 22 28 12 27 7 10 7 2 15 27 2 8 16 8 12 28 11 13 10 h 0 0 0 0 0 0 3 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 20 0 25 0 0 0 0 0 0 0 0 0 0 0 0 0 . 0 0 0 .n 0 0 0 0 V Vv V V Vv V Vv V V V Vv V Vv V V V Vv V V V V V Vv V Vv V Vv V V Vv Rr Hr r Rr r Rr Hr Rr R R r R Rr R Rr R r r R R R r Rr r r R r Rr r R N Nn N N Nn Nn N Nn n N n Nn Nn Nn n N n n n n Nn Nn Nn n n Nn Nn N n Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. b Bb b B Bb Bb Bb Bb Bb Bb Bb b B b B B B Bb b Bb b Bb Bb Bb b Bb Bb b B B 6^ TABLE A . ( c o n t in u e d ) F 3 rows number 23031 32 33 3h 35 36 37 38 39 ho . Ul U2 U3 Head characteristics of F 2 plants Inoculated Its. obtained Infection 2-rowed or Rough or Covered Blade or pet. 6—rowed smooth or naked white lemma oiaï Inf'ected number number and pericarp 15 5 6 .7 15 6 12 0 0 0 6 1 1 0 0 0 0 1 0 7 1 8 0 3 15 20 0 0 0 iu.28 6.66 0 0 0 0 5 0 iu.28 0 V Vv V Vv V Vv V Vv V V V V Vv Rr r Rr Rr Rr r Rr Rr N Nn Nn n n N N Nn — — Rr r r Rr n n N Nn Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Bb B B Bb Bb B b Bb Bb Bb B Bb Bb 66 Table B. Percentages of Infection of Families. Morphological Charac­ teristics of F 2 Plants of the Gross Jet x Harlan ^3 rows number 230LL U6 ' U7 U8 h9 ^0 51 52 53 5U 55 56 57 58 59 60 61 62 63 6U 65 66 67 68 69 70 71 72 73 71* 75 76 77 78 79 80 81 Inoculated Head characteristics ->f F2 plants pits. obtained Infection 5-rowed Rough or Covered Black or Total Infectied pet. or 6-rowed smooth or naked white lemma number number and pericarp 13 30 33 18 28 16 2U 2U 3 8 21* 31 20 32 9 29 33 18 12 18 20 5 12 20 21 26 20 10 10 37 29 18 6 22 22 12 8 5 3 8 0 1 0 0 0 2 0 0 1 3 5 1 ■ 8 0 • 13 0 2 U 5 0 1 0 0 0 2 2 1 1 0 0 0 0 0 3 0 0 23.07 26.66 0 5.55 0 0 0 8.33 0 0 i*.l6 9.67 25 3.12 88.88 0 39.39 0 16.66 22.22 25 0 8.33 0 0 /0 10 20 10 2.70 0 0 0 0 0 25 8 0 V V V Vv Vv Vv Vv Vv Vv Vv Vv V V Vv V Vv Vv V Vv Vv V V Vv V V Vv Vv V Vv V Vv V V V V V V Vv R R N Nn — — R Rr R Rr Rr r R Rr R R Rr R Rr Rr R R R R Rr Rr Rr R R R R R R r Rr Rr R R Rr R R n Nn Nn Nn Nn n N n Nn Nn Nn N Nn Nn Nn Nn N Nn Nn N Nn Nn Nn N n n n Nn Nn Nn N n N n N Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. . b Bb B b b Bb Bb Bb Bb B b Bb B b b Bb Bb Bb b B Bb Bb b Bb Bb Bb Bb Bb B Bb Bb Bb b Bb Bb Bb B Bb 67 Table B, (Continued) \ rows number 23082 83 8U 85 86 87 88 89 90 91 92 93 9h 95 96 97 98 99 23100 101 102 103 lOU 105 io6 107 108 109 110 111 112 113 llU 115 116 • 117 118 119 120 121 122 Inoculated pits. obtained Total inTectedl number number 7 22 lU 15 18 15 19 10 13 9 9 16 15 19 lU 30 19 11 15 8 8 13 16 h 7 23 29 11 16 10 22 15 13 19 29 13 28 lU 22 16 22 0 0 2 1 0 0 0 0 11 0 0 0 0 5 0 1 3 2 0 1 1 0 0 0 1 1 2 0 0 0 0 1 1 2 7 0 5 1 0 1 h ■ Head characteristics of Fg plants Black or Aough or Covered Infection 2-rcwed pet. or 6-rowed smooth or naked white lemma and pericar 0 0 lU.28 6.66 0 0 0 0 8U.61 0 0 0 0 26.31 0 0.03 15.78 18.18 0 12.5 12.5 0 0 0 lU.28 U.3U V Vv V V Vv Vv Vv Vv V Vv V Vv Vv V Vv V Vv Vv V Vv V V Vv Vv Vv Vv 6.0 V 0 0 0 0 6.66 7.68 Vv 10.52 2h.l3 0 17.85 7.1U 0 6.25 18.18 V Vv V V Vv Vv V V Vv V Vv Vv Vv Rr r Rr Rr r Rr R R Rr Rr r R R R Rr R Rr r R R R R Rr R r R R R Rr R R Rr R R r r R R Rr R R n n N Nn n n N n N Nn n N Nn Nn N Nn N Nn Nn Nn N Nn n n N N n n Nn n Nn n n Nn Nn Nn Nn n Nn Nn Nn Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Bb b b b Bb B B B Bb Bb Bb Bb Bb B Bb Bb Bb Bb Bb B b B Bb b B b b Bb Bb B Bb B Bb Bb Bb B b b b Bb b 68 T a b le B . ( C o n t in u e d ) “3 rows number 23123 I2ii 125 126 127 128 129 130 131 132 133 13U 135 136 137 138 139 lltO lUi 1U2 1U3 Ihh 1U5 1U6 1U7 1U8 llt9 150 151 152 153 15U 155 156 157 158 159 160 161 162 163 16I4 165 Inoculated pits * obtained Infection Total Infected pet. number number 9 18 27 10 20 6 '12 15 21 10 13 5 6 7 9 Q 16 9 h 8 13 16 6 16 8 6 5 8 11 16 8 16 13 lU 3U 22 13 17 13 h 1 12 17 0 0 0 0 3 0 6 0 1 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 6 0 0 0 0 15 . 0 50 0 U .76 0 0 0 0 0 0 0 0 0 25 12.5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8.33 35.29 Head characteristics of Fg plants Black or 2-rowed Rough or Covered or 6-rowed smooth or naked white lemma and nericarp Vv V V V Vv Vv V Vv Vv Vv Vv Vv Vv V Vv Vv V V Vv V V V Vv V Vv Vv Vv Vv Vv V Vv Vv V Vv V V Vv Vv Vv V V Vv V R R r R R R R R R r R r R R R R R R R Rr Rr Rr Rr Rr r R R R Rr r Rr Rr R R r r R Rr Rr R Rr R R Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Nn n Nn N Nn n Nn Nn Nn H N Nn Nn n Nn Nn N Nn n Nn n Nn n N n Nn n Nn Nn Nn Nn N N Nn Nn Nn Nn n Nn Nn Nn Nn Nn b B b Bb b . Bb Bb b B b Bb Bb Bb B Bb b Bb B B b B Bb B B B b Bb B Bb Bb B Bb Bb Bb B b Bb B Bb Bb Bb b b T a b le B , ( C o n t in u e d ) rows lumber 23166 67 68 69 70 71 72 73 7U ' 75 76 77 78 79 80 81 82 83 Head characteristics of F2 Inoculated dough or Covered Black or pits. obtained Infection 2-rowed pet. or 6-rowed smooth or naked white lemma ¥0 tal Infected and pericarp number number 16 9 7 11 0 0 0 1 8 10 6 7 3 16 6 2 3 2 0 n 0 0 0 2 0 0 0 0 0 9.09 Vv Vv 33.33 V 0 0 V V — "T V — — 5 0 0 — _ — 6 7 6 3 18 U 10 7 1 1 0 0 0 16.66 0 0 0 0 0 0 0 0 0 0 0 0 U 6 6 3 — 5 3 2 9 7 11 15 18 11 0 0 0 , 0 ' 0 0 0 0 — 0 . 0 0 0 0 0 0 1 0 — 7 0 V 0 0 0 0 0 - 0 Vv Vv ■V V V 25 — — 8U 85 86 87 88 89 90 91 92 93 9li 95 96 97 98 99 23200 1 2 3 U 5 6 7 8 9 69 — 0 0 0 0 0 0 0 5.55 0 — 0 V V Vv V V Vv Vv Vv V Vv V V Vv V V — R R Hr R . n Nn Nn N B b b B r Rr R Rr R R R Rr Rr n Nn Bb M b Bb Bb Bb B B Bb n n Nn n N Nn — — — - r Nn — — — Rr R Rr R R Rr Rr R R R r R R Nn n n Nn n n Nn n Nn N Nn Nn n B — b — Bb Bb b Bb B Bb Bb B Bb B B b Bb — — V V V V Vv Vv Vv R R r Rr Rr Rr r n n N Nn Nn Nn N V V - — - R n Bb Ml — — — n B Vv r Reproduced with permission o f the copyright owner. Further reproduction prohibited without permission. — b . Bb Bb B Bb B Bb 70 T a b le B . ( C o n t in u e d ) F 3 rows number 23210 11 12 13 lU 15 16 17 18 19 20 21 22 23 2U 2$ 26 27 28 29 30 31 32 33 3h 36 37 38 Inoculated Head characteristics of F2 plants pits. obtained Infection 2-rowed Rough or Covered Black or pet. or 6-rowed smooth or naked Total Infected white lemma number -number and pericarp 0 0 0 0 0 0 0 0 V Vv Vv V Vv Vv Ilf 5 8 1 2 10 0 1 — - 9 11 7 8 h 6 h 10 2 8 11 h h 3 8 13 11 7 •Q 0 0 0 n 0 0 1 2 0 0 0 0 1 0 0 0 0 1C 100 0 0 0 0 33.33 0 0 0 0 Vv V 8 8 If 0 0 0 0 0 0 Vv Vv 10 mm — 0 0 0 0 0 0 0 Vv V v V Vv V Vv V — Vv Vv V V Vv Vv V V Rr r R R R Rr n Nn Nn N N Nn Bb B Bb Bb B Bb R R r R R Rr R Rr n M N N Nn n n Nn Bb B B B Bb Bb B Bb - — — Rr Rr R Rr R r R R Rr .N n Nn n N N n Nn Nn b Bb Bb Bb b B b B B Rr R R Nn n n Bb B B Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 71 Table G. Percentages of Infection of Families. Morphological Charac­ teristics of F2 Plants Based upon the Behavior of F^ Families of the Cross Jet x Ogalitsu F2 rows number 23239 Uo Ui h2 U3 hh 1x6 hi 1x8 h9 50 51 Head characteristics of F2 plants Inoculated olts. obtained Infection 2-rowed Rough or Covered Black or pet. Total Infected or 6-rowed smooth or naked vdiite ]emma and nericarp number number 12 11 31 1 lU 18 9 8 5 7 2 7 h 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 5.55 0 0 0 0 n 0 0 V V Vv V Vv V Vv Vv V Vv Vv V Vv Rr R r R Rr Rr Rr R R R Rr R r Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. N Nn n Nn Nn Nn Nn Nn Nn Nn Nn N N b Bb Bb Bb Bb Bb 3b Bb b Bb B Bb B 72 Table D, Percentages of Infection of F3 Families of the Cross Harlan x Anoidium F 3 rows number 23252 S3 SU SS S6 S7 SB S9 60 61 62 63 6U 6S 66 67 68 69 70 71 72 73 7U 7S 76 77 78 70 80 81 82 83 8U 8S 86 87 88 89 90 Inoculated pits. obtained Total Infected numb e r number 28 32 30 26 3S 28 12 2S 2S 23 30 26 23 26 23 27 9 30 26 23 30 13 23 16 IS 22 10 21 23 2S 20 12 21 21 2S 22 22 16 17 Infection pet. . 0 0 0 0 12 0 2 6 U 0 0 0 0 0 U 6 0 3 6 16 0 0 7 0 3 0 6 0 17 0 3 0 0 0 12 0 U 2 0 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 0 0 0 0 3U.28 0 16.66 2U 16 0 0 0 0 0 17.39 22.22 0 10 23.07 69.S6 0 0 30 .U3 0 20 0 60 0 73.91 0 IS 0 0 0 U8 0 18.18 12.5 0 73 T a b le D , ( C o n t in u e d ) Tnoculated rows number 23291 92 93 9h 9S 96 97 98 99 300 1 2 3 U 5 6 7 8 9 10 11 12 13 lit 15 16 17 18 19 20 21 22 23 2U 25 26 27 28 29 30 31 32 33 3U 35 Infected number Infection pet. 21 Ih 18 27 2li 7 26 13 19 22 16 lU 12 32 18 17 25 6 13 21 18 16 35 22 31 19 20 37 11 12 6 3 0 2 0 0 13 0 3 7 3 U 0 1 2 5 U 0 1 6 0 0 0 0 1 0 13 5 1 3 28.37 21.28 0 7 .U0 0 0 50 0 15.78 31.01 18.75 28.57 0 3.12 11.11 29 .Ui 16 0 7.68 28.52 0 0 0 0 3.22 0 65 13.51 9.09 25 — — - 1 0 0 13 5 0 8 0 0 5 0 19 1 2 10 0 0 56.52 13.51 0 36.36 0 0 U1.66 0 63.33 U.5U 13.33 Total number 10 U 17 23 37 U2 22 9 3U 12 19 30 22 15 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. T a b le D , ( C o n t in u e d ) 7U I n o c u la t e d p i t s . o b t a in e d F 3 rcr.TS number 23336 37 38 39 ho hi h2 U3 hh h^ h6 hi U8 h9 SO Si. S2 S3 SU SS S6 S7 SO S9 60 61 62 63 6U 6S 66 67 68 69 70 71 72 73 7U 7S 76 77 78 79 60 Total number 23 7 30 22 16 18 23 21 23 30 23 20 12 10 19 27 1^ 21 17 2S 21 27 21 30 32 2U 32 19 23 17 20 IS 7 17 2U 25 23 27 19 18 9 21 10 20 2S Infected number Infection pet. 0 0 22 0 0 0 0 0 0 19 6 1 0 0 0 2 0 0 0 0 0 0 2 0 0 1 10 IS 0 0 7 3 0 0 12 1 0 3 S 7 2 0 0 IS 0 0 0 73.33 0 0 0 0 0 0 63.33 26.08 S 0 0 0 7 .U0 0 0 0 0 0 0 9.52 0 0 U .16 31.2s 78.9U 0 0 3S 20 0 0 SO u 0 11.11 26.31 38.88 22.22 0 0 75 0 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. â T a b le D , ( C o n tin u e d ) F 3 rovTs number 23301 82 83 8ii 85 86 87 88 89 90 91 92 93 9h 05 96 97 98 90 Uoo 1 2 3 h 75 I n o c u la t e d p i t s . o b ta in e d Total number 11+ 12 12 1 16 16 18 25 22 13 15 12 20 32 13 8 26 10 22 17 ,2U 22 23 21 Infected number 1 2 0 0 0 8 7 13 0 0 5 0 0 1 0 0 1+ 3 7 1 3 19 0 8 5 16 0 6 18 21+ 21 20 21 25 10 15 22 1 18 7 8 9 10 11 12 13 11+ 15 16 17 18 19 20 21 22 23 21+ 21+ 25 11+ Infection pet. 18 9 2 1 1 1 + 0 0 5 0 11+ 1+ 18 il+ 12 15 17 12 11+ 3 1+ 0 0 1 25 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 7 .11+ 16.66 0 0 0 50 38.68 52 0 0 33.33 0 0 3.12 0 0 15.38 16.66 31.81 5.08 12,50 86,36 0 38.09 0 5.55 75 85.71 • 1+5 9.52 U 10 26.66 0 0 20 0 28.57 77.77 25 26.66 0 0 7.11+ T a b le D . ( C o n t in u e d ) rows number 23L26 27 28 29 3G 31 32 33 3h 3^ 36 37 38 39 Uo Ul U2 U3 UU US U6 U7 U8 U9 50 51 52 53 5U 55 56 57 58 59 60 61 62 63 6U 65 66 67 68 69 70 76 I n o c u la t e d p i t s . o b t a in e d Total number 15 12 13 11 5 lU 20 2U 25 22 28 10 22 13 22 2 25 12 21 18 lU 20 16 11 15 18 12 11 lU 11 19 21 17 22 16 12 25 lU 13 12 21 7 8 2 9 Infected number Infection pet. 7 0 11 1 2 8 0 lU 20 2 , u 0 U 0 U 0 8 3 0 7 0 2 11 3 0 13 0 9 5 0 12 3 10 5 1 3 23 8 2 0 18 0 1 0 1 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U6.66 0 U6.66 9.09 UO 57. lU 0 58.33 80 9.09 lU.28 0 18.18 0 16.18 0 32 25 0 38.88 0 10 68.75 27.27 0 72.22 0 8.81 35.71 0 63.15 lU.28 58.82 22.72 5.55 25 92 57.lU 15.38 0 85.71 0 12.50 0 11.11 T a b le D . ( C o n t in u e d ) 77 ï r io c u la t e d n i t s , o b ta in e d ro w s In fe c t io n number Total number _ ïnfected number 23k71 72 73 11 23 10 31 1 17 22 29 32 17 16 18 15 6 0 1 5 0 0 11 0 1 0 12 0 8 3 0 7h 7S 76 77 78 79 80 ■ 81 82 83 8U 85 , 10 35 pet. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 5L.5L 0 10 16.12 0 0 50 0 3.12 0 75 0 53.33 15.78 0 I 76 Table E . Percentages of Infection of F 2 Families of the Cross Harlan x Ogalitsu F3 rows number 23U86 ,87 88 89 90 91 92 93 9U 9$ 96 97 98 99 500 1 2 3 U 5 6 7 8 9 10 11 12 13 lU 1!^ 16 17 18 19 20 21 22 23 2U 2$ Inoculated pits, obtained Total Infected number number 21 27 16 2h 3U ill 10 18 33 2h 11 22 22 20 27 38 22 16 18 2h $ ho 27 30 7 2h 7 21 10 12 11 22 11 8 17 13 Infection pet. 1 0 1 1 1 0 2 2 1 0 2 3 1 0 10 2 2 2 u 0 0 0 3 0 0 2 0 0 0 1 1 0 00 — - - - 3 8 0 0 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U .76 0 6 .2$ It.16 lit.70 2.13 0 11.11 6.06 It.16 0 9.09 13.63 5 0 26.31 9.09 12.$0 11.11 16.66 0 0 0 16.66 U2.8$ 0 0 ^.$2 0 0 0 U.5U 9 .0 9 0 0 0 0 0 • 79 T a b le E . ( C o n tin u e d ) '2 rows number 23526 27 28 29 30 31 32 33 3U 35 36 37 38 39 Uo Ul U2 U3 UU U5 U6 U7 U8 U9 50 51 52 53 5U 55 56 57 58 50 60 61 62 63 6U 65 66 67 . 68 69 70 Inoculated pits. obtained Infected Totel number number — U Uo 11 15 3)4 8 U2 9 15 26 21 2U 2 25 — lU 15 16 1 — u — 5 — 8 1 — 3 1 — 17 8 — 1 — 9 1 11 9 6 — 2 9 11 Infection pet. — 0 8 2 0 3 1 3 U 0 1 0 2 — 0 20 18.18 0 8.82 12.5 7.1U uu.uu 0 3. OU 0 8.33 0 0 3 — 3 0 2 0 0 0 — 0 0 0 0 0 0 — 0 — 2 0 1 0 n - 0 2 3 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 12 21.U2 0 12.50 1 0 0 0 0 0 0 0 0 0 mm 22.22 0 9.09 0 0 - 0 22.22 27.27 I T a b le S . ( C o n tin u e d ) 80 I n o c u la t e d p i t s . o b ta in e d In fe c t io n nuToer Total number 23571 72 73 7U 75 76 77 78 79 80 81 82 83 1 5 lU 3 0 0 0 0 — - — 0 0 0 0 5 1 0 0 0 0 0 0 31.25 5.55 0 0 19 6 2 7 16 18 10 13 Infected number Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. pet. 0 n 0 0 81 Table F . Percentages of Infection of Fj Families of the Gross Ogalitsu x Anoidium F 2 rows number 23281 82 86 87 88 89 90 91 92 93 9U 92 96 97 98 99 .600 1 2 3 h 2 6 • 7 8 9 10 11 12 13 lU 12 16 17 18 19 20 21 22 23 Inoculated pits, obtained Total Infected number numbe r h — 2 2 7 1 12 10 6 3 h 8 18 2 U 10 1 9 10 h 20 h 11 11 h 11 8 8 8 6 2 9 10 8 10 3 12 11 10 1 Infection pet. 0 1 1 1 0 0 0 0 0 0 U 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 2 1 0 0 h 0 0 0 0 2 0 1 0 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 0 — SO . 20 lL.28 0 0 0 0 0 0 20 0 0 0 n 0 0 0 0 0 0 0 0 0 9.09 0 22 12.20 0 0 1*U.UU r\ 0 0 0 16.66 0 10 0 T a b le F . ( C o n tin u e d ) rows number 2362L 2^ 26 27 28 29 30 31 32 33 3U 35 36 37 33 39 Uo Ul U2 U3 UU U5 U6 U7 U8 U^ 50 51 52 53 5U 55 56 57 58 59 60 61 62 63 6U 6^ 66 67 68 82 Inoculated pits. obtained Total Infected number number 3 6 U lU 1 3 10 7 11 5 10 17 U 6 15 8 8 11 2 2 5 - U 15 2 6 2 1 1 9 12 6 U 2 1 1 2 11 7 • Infection pet. 1 0 0 3 0 0 0 0 0 0 2 0 0 0 1 2 0 0 0 0 0 33.33 0 0 21.U2 0 0 0 0 0 0 20 0 0 0 6.66 25 0 0 0 0 o - - 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 — - 9 3 5 8 U 1 0 0 0 1 Reproduced with permission o f the copyright owner. Further reproduction prohibited without permission. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11.11 0 0 0 25 i T a b le F , ( C o n tin u e d ) 83 T n ô c u ïa tê d p i t s . o b ta in e d In fe c t io n number Total number Infected number pet. 23669 70 71 72 73 7U 7S 76' 77 78 79 80 81 82 83 8U 85 86 87 88 89 90 91 92 93 .«U 95 96 97 98 99 700 1 2 3 U 5 6 7 8 9 10 11 12 13 Hi 15 16 1 2 Hi 6 7 7 ii 5 7 7 3 5 3 3 5 Hi 0 0 ii 1 1 2 0 0 1 2 1 0 0 0 0 0 0 0 28.57 16,66 Hi.28 25.57 0 0 lit.28 28.57 33.33 0 0 0 0 0 — 3 13 3 5 17 5 it 1 6 it 5 2. Hi 7 9 10 5 9 15 10 • Hi 5 11 11 9 ii 10 12 9 3 7 — 0 0 0 n 0 1 2 0 0 0 0 0 2 0 0 0 0 0 2 0 3 0 2 0 1 0 0 0 0 0 0 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. - 0 0 0 0 0 20 50 0 0 0 ' 0 0 Ik.28 0 0 0 0 0 13.33 0 21.U2 0 18.18 0 11.11 0 0 0 0 0 0 I T a b le F . ( C o n tin u e d ) F 2 rows number 23717 18 19 20 21 22 23 2h 2S 26 27 28 29 30 31 32 33 . 3k 35 36 37 38 39 Uo • Ul U2 U3 UU U5 U6 U7 U8 U9 8L Inoculated pits. obtained_____ Total infected numbe r numb e r o U lU 16 7 2 3 7 7 8 U 20 1 13 9 3 3 6 6 3 7 17 12 11 16 Infection pet. 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 1 c 0 0 3 o 1 0 0 0 0 0 U2.85 0 0 0 0 0 c 0 0 0 0 0 0 16.66 0 0 0 17.6U 0 9.09 0 — — — — — 7 0 0 — — — 0 0 2 - 0 0 3 5 8 - Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 25 - 85 Table G, Percentages of Infection of the Susceptible Variety o.A.C. 21 Row number 1 2 3 U 5 6 7 8 9 10 11 Inoculated pits. obtained Infected Total number number u 1 6 h 1 3 3 1 2 3 2 Infection pet. 2 0 2 2 0 2 1 o' 0 2 1 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 50 n 33.33 50 0 66.66 33.33 0 0 66.66 50