BROMINE RETENTION IN sous AND UPTAKE 0F BROMINE BY PLANTS AFTER sou. FUMIGATION masts FOR THE DEGREE 0? m. D, MICHIGAN STATE COLLEGE ZENOEEUS. STELMACH asss ! MESW: LIBRARY Michigan State University This is to certify that the thesis entitled Promine Retention in Soils and Uptake of 'romine by Plants After $011 Fumigation presented by Zenob ius Stelmch has been accepted towards fulfillment of the requirements for Doctor's degree in Philosophy WLM Major professor Date M 0-169 BROHINE RETENTION IN SOILS AND UPTAKE OF BROMINE BY PLANTS AFTER SOIL FUMIGATION BY Zenobiue'Stelnach AN ABSTRACT Submitted to the Sehoel of Greduete Studies of Miehigen State College of Agriculture and Applied Science in pertiel fulfill-ant of the requiremente for the degree of DOCTOR OF PHILOSOPHY Department of Soil Science 1955 Approved 0‘ l: EU'U'E Zenobiue Stelmach ABSTRACT The study of bromine retention by some soils and up- take of bromine and its effect upon plants was carried out in the field and in the greenhouse. Hillsdale, Brady and Houghton soils were used in field study, and Brookston, Oshtemo and Houghton soils were used in the greenhouse. Plots of Hillsdale soil were treated with the'foflowing fumigants in the amount corresponding to the rate per acre: methyl bromide, 435 pounds; sodium bromide, 475 pounds; ethylene dibromide W-85, 9 gallone; and untreated-check. Whole bean plants, bean pods and soils from Hillsdale soil were sampled at three-weekly intervals and analyzed for total and water extractable bromine, respectively. Plots of Brady soil were treated with 435 pounds of methyl bromide, 9 gallons of ethylene dibromide W-85, and check. All rates were based on acre basis and all treatments randomized and replicated. Beans and table beets were grown on Brady soil and two samplings of plants and soils were taken for total bromine analysis. On Houghton soil table beets were planted and soil treatment was the same as for Brady soil. In the greenhouse surface samples of Brooketon, Osh- temo, and Houghton soils were treated with sodium bromide at the rate of 108.8 pounds of sodium bromide per acre. Two eamplings of plants and soils were taken for analyeie. Zenobius Stelmach 2. All bromine analyses were done by method described by Shrader, gt El. Bean and cabbage plants grown on Hilledale soil accum- ulated a considerable amount of bromine during the early stage of growth, but with the progress in growth this amount decreased markedly. The same was true with water extractable bromine of soil which tended to diminish also. An exception was soil treated with sodium bromide in which there was a considerable accumulation of bromine during growing season. The yield of bean pods rated decreasingly: W-85, check, Mc-Z, NaBr; that of cabbage was affected in exactly the same way as above; yield of potatoes: Mc-Z, W-85, check, NaBr; and yield of peanuts: W-85, Mc-2, check, and NaBr. In Brady soil the highest amount of total bromine was in methyl bromide treated plots, and it was the highest also in bean pods and beete from corresponding plots. Yield of beans and table beets was as follows from highest to lowest: ethylene dibromide, methyl bromide, and check. A quality rating of table beets was as follows: ethylene dibromide, methyl bromide, and check. On Houghton muck, however, the yield of beets from methyl bromide treated plots was the highest, and that from plots treated with ethylene dibromide was the lowest because of reduced stand caused by damping-off fungi. There were significant increases in yield of bean pods and table beets grown in greenhouse in soils treated with Zenobiue Stelmach 3. sodium bromide. No significant differences were found in the amount of bromine present in either plant tissue or soil, or in the yield, due to high or low soil moisture contents. The highest native content of bromine was in Oshtemo, next in Brookston, and the lowest was in Houghton soil. The highest and most significant retention of bromine was in Houghton, the lowest in Oshtemo, and it was intermediate in Brookston soil. In the dry year 828 ppm of bromine in bean plants grown on sodium bromide treated plots, on Hillsdale soil, seemed to depress growth of plants, whereas in the year with adequate rainfall 866 ppm found in bean pods near maturity did not cause any harm to plants and resulted in a higher yield of beans than from untreated plots. In the field experiment 975 ppm of bromine in beets and 176 ppm in Houghton muck, found in samples taken on September 25, 1954, were harmful to beet's development. On the other hand, as much as 1062 ppm of bromine in beets, grown in the greenhouse, did not cause any damage. In bean plants grown on soil not treated with bromine, the highest content of bromine was in stems, next in roots; and the lowest was in leaves. In bean plants from treated plots the highest amount of bromine was in roots, lower in leaves, and the lowest in stems. BROMINE RETENTION IN SOILS AND UPTAKE OF BROHINE BY PLANTS AFTER SOIL FUHIGATION BY Zencbiue Stelmach A THESIS Submitted to the School of Graduate Studiee of Michigan State College of Agrieulture and Applied Science in partial fulfillment of the requiremente for the degree of DOCTOR OF PHILOSOPHY ‘ Department of Soil Science 1955 /—7-5‘? 9* 3“ a?‘ .215 ACKNOWLEDGEMENTS The author wishes to express his sincere gratitude to Dr. J. F. Davis for his generous assistance and supervision during the course of this investigation. Acknowledgements are also due Dr. R. E. Lucas, under whose supervision and inspiration this investigation started, DPS. R. L. Cook, 8. J. Benne and K. Lawton, for their gener- ous assistance in the preparation of this manuscript, and other members of Soil Science Department for helpful sugges- tions and assistance in one way or another. The author is grateful to his fellow graduate students for their criticism, to his colleagues, Messers. S. Ilnytzky and A. Jaciuk and also to his relatives, Mr. and Mrs. G. Stelmach and Mr. and Mrs. O. Zacharkiw for their financial support without which this work would not be completed. In addition, he desires to thank the Dow Chemical Company for supplying the necessary chemicals. Dissertation: Vita Zenobius Stelmach candidate for the degree of Doctor of Philosophy Bromine retention in soils and uptake of bromine by plants after soil fumigation. Outline of Studies: Major subject: Soil Science Minor subject: Botany Biographical Items: Experience: Member: Born, September 1, 1918, Zolotnyky, Ukraine Undergraduate and graduate studies at Poly- technic of Lviv, 1938-1939; Ukrainian Tech- nical University, Regensburg, 1945-1948; Michigan State College, 1952-1955. Agronomist at Landwirtschaftskammer, Lviv, 1941-1944; Students' supervisor at Ukrainian Technical University, Regensburg, 1946-1947; Movement and accommodation officer at Inter- national Refugee Organization, Germany, Society of Ukrainian Engineers in America Society of Friends of Ukrainian Technical University Society of Sigma Xi TABLE INTRODUCTION . . LITERATURE REVIEW . . OF CONTENTS EXPERIMENT I--METHODS AND PROCEDURES Method for Determination of Total Bromide Experimental Results and Discussion Cabbage . . . Beans . . . . Potatoes and Peanuts EXPERIMENT II--METHODS AND PROCEDURES Experimental Results EXPERIMENT III-~METHODS Experimental Results Beane . . . . Table Beets . . SUMMARY AND CONCLUSION Part I . . . . . . Part II C O O O O 0 Part III . . . . . LITERATURE CITED . . . APPENDIX . . . . . . . and AND and Discussion PROCEDURES Discussion 14 l? 20 2O 22 26 29 32 4O 45 45 50 62 62 64 66 69 75 TABLE II. III. IV. VI. VII. VIII. IX. XI. XII. XIII. XIV . XV. LIST OF TABLES PAGE Total Bromine (ppm) in Cabbage Plants from Hille- dale 5011, MSC Farm, East Lansing . . . . . . . . 21 Water Extractable Bremime in ppm in Soil frem Cabbage Plots, MSC Farm, East Lansing . . . . . . 21 Total Bromine in ppm in Bean Plants from Hille- dale Soil, MSC Farm, East Lansing . . . . . . . . 24 Total Bromine in ppm in Bean Pods from Hilledale ' Soil, MSC Farm, East Lansing. . . . . . . . . . . 24 Water Extractable Bromine in ppm in $011 from Bean Plots, MSC Farm, East Lansing . . . . . . . 25 Mean Yields of Crops of Four Replicatione from Hilledale Soil, MSC Farm, East Lansing . . . . . 25 Mean Yield of Crops (Four Replications) from Hille- dale Soil, MSC Farm, East Lansing . . . . . . . . 28 Total Bromine ppm in Soils and Beet Roots from Brady Loam Soil, MSC Experimental Muck Farm, Clinton County, Miehigan . . . . . . . . . . . . 34 Total Bromine ppm in Soils and Beet Roots from Houghton Musk Soil, MSC Experimental Muck Farm, Clinton County, Michigan . . . . . . . . . . . . 36 Yield of Crops on MSC Experimental Muck Farm (Means of Four Replieations in Pounds) . . . . . 36 Total Bromine ppm in Soils and Beet Roots from Spots of Detrimental Beet Growth and Close Vicinity on Houghton Musk, Clinton County, Michigan . . . 38 Total Bromine ppm in Soils and Bean Pods from Brady Loam Soil, MSC Experimental Musk Farm, Clinton County, Michigan . . . . . . . . . . . . 38 Soils Used in Greenhouse Experiment . . . . . . . 41 Watering Scheme for Table Beets and Beans . . . . 43 Total Bromine Content (ppm) in Bean Pods Grown in Greenhouse and Sampled on October 3, 1954 . . . . 46 TABLE XVa. XVI. XVIa. XVII. XVIIa. XVIII. XVIIIa. XIX. XIXa. XXa. XXIa. LIST CF TABLES (continued) Analysis of Variance of Total Bromine Content (ppm) in Bean Pods grown in Greenhouse and Sampled on October 3, 1954 . . . . . . . . . . . Total Bromine ppm in Bean Pods sampled on November 14, 1954 (Greenhouse) . . . . . . . . . Analysis of Variance of Bromine ppm in Bean Pods sampled on November 14, 1954 . . . . . . . . . . Total Bromine Content (PPm) in Soils from Green- houee Which were Sampled on October 3, 1954 . . Anal sis of Variance of Total Bromine Content (ppm in Soils from Greenhouse (Bean Pots) - Samplings of October 3, 1954 . . . . . . . . . . Total Bromine Content (ppm) in Soils from Green- house which were Sampled on November 14, 1954, (B.‘n Pot.) O 0 O O O O O O O O O O O O O 0 O 0 Analysis of Variance of Bromine ppm in Soils from Greenhouse (Bean Pots), sampled on November 14, 1954 O O C O C C O O O O C O O O O O O O O O O 0 Yield of Bean Pods (grams) Sampled on October 3, 1954, from Greenhouse . . . . . . . . . . . . . Analysis of Variance of Yield of Bean Pods (gram?) Sampled on October 3, 1954, (from Green- houee . . . . . . . . . . 3 . . . . . . . . . . Yield of Bean Pods in Grams from Soils which were used for Greenhouse Study (Sampled on NOV.mb.r 14’ 1954) O O O O O 0 O O O O O O O 0 Analysis of Variance of Yield of Bean Pods from Soils used in Greenhouse (Sampled on November 14, 1954) O O O O O O 0 O O O O O O O O O O O O O 0 Total Bromine Content (ppm) in Beets from Green- house which were Sampled on November 14, 1954. . Anal sis of Variance of Total Bromine Content (ppm in Beets from Greenhouse which were Sampled on November 14, 1954 . . . . . . PAGE 46 48 48 49 49 51 51 52 52 53 53 54 54 TABLE XXII. XXIIa. XXIII. XXIIIa. XXIV. XXIVa. XXVa. XXVI. XXVIa. XXVII. LIST OF TABLES (concluded) PAGE Total Bromine Content (PPm) in Soils from Green- house (Beet Pots) Sampled on November 14, 1954 . 55 Anal sis of Variance of Total Bromine Content (ppm in Soils from Greenhouse (Beet Pots) Sampled on November 14, 1954 . . . . . . . . . . 55 Total Bromine Content (ppm) in Soils from Greenhouse Sampling on December 29, 1954 . . . . 56 Anal sis of Variance of Total Bromine Content (ppm in soils from Greenhouse sampling of DCGOHlbOI‘ 29 ’ 1954s e s e s e e e e e e e e e e e 56 Total Bromine Content ppm in Best Tissue from Greenhouse Sampling of December 29, 1954 . . . . 58 Analysis of Variance of Total Bromine Content (ppm) in Beet Tissue Samples of December 29, 1954 58 Yield of Table Beets (grams) from Greenhouse, Sampled on November 14, 1954 . . . . . . . . . . 59 Analysis of Variance of Yield of Table Beets (grams) which were Sampled on November 14, 1954, from Greenhouse . . . . . . . . . . . . . . . . 59 Yield of Table Beets (grams) grown in Greenhouse and Sampled on December 29, 1954 . . . . . . . . 50 Analysis of Variance of Table Beets' Yield (grams) (Greenhouse samplings of December 29, 1954) . . 60 Total Bromine Content (ppm) in the Parts of Bean Plants which were Grown in Greenhouse and were Sampled at the Stage of Maturity . . . . . . . . 61 Figure 10. 11. 12. LIST OF FIGURES Left: On top - normal, healthy leaf of table beet plant; next three leaves below are from the spot of high bromine content in Houghton muck. Right: Leaf affected by high bromine content Houghton muck . . . . . . . . . . . . . . . . Table beet plants in early stage of growth on Houghton [DUCK e e e e e e e e e e. e e e e e e PPM bromine in cabbage plants grown on Hills- dale sandy loam (mean of four replicates) . . in PPM water extractable bromine in Hillsdale soil (cabbage plots). Means of four replicates . PPM bromine in bean plants grown on Hillsdale sandy loam. (Means of four replicates) . . . PPM bromine in bean pods grown on Hillsdale sandy loam. (Means of four replicates) . . . PPM water extractable bromine in Hillsdale soil from bean plots. (Means of four replicates). PPM bromine content of bean pods grown on Brady soil. (Means of four replicates) . . . . . . PPM bromine content of table beets grown on Brady soil. (Means of four replicates) . . . PPM bromine content of table beets grown on Houghton muck. (Means of four replicates) . PPM bromine content in bean pods grown in green- house on three soils (low moisture level) . . PPM bromine content of beet roots grown in greenhouse on three soils (low moisture level). Page 76 77 78 79 80 83 84 85 87 INTRODUCTION Since Pasteur's investigations and discovery of cer- tain bacteria as causal agents of different diseases, much progress has been made in methods of sterilization and disease prevention. With further development of plant pathology and para- sitology, sterilization of soil by heat, steam, and chemicals (16, 53, 4, 8) has been carefully and thoroughly investigated. Soil sterilization is an eradication of all or some of the micro-organisms, plants, insects, and/or animals living in the soil. This treatment can be of different duration, and is designated as: (a) Permanent soil.sterilization-- duration more than two years; (b) Semi-permanent sterilizer tion--duration from four months to two years; and (c) Tempor- ary or partial soil sterilization--duration of less than four months. Partial soil sterilization kills nematodes, some fungi and bacteria, but never all of them. It is also called soil fumigation if it is performed by gaseous compounds, and in this study these two terms are used interchangeably. As reported by many workers (24, 59, 40, 42, 44, 67), the fumigation of soils with bromine carriers was success- fully used in the control of golden nematodes of potatoes, Heterodera rostochignsis; sugar beet nematodes, Heterodera schaohtii; bulb nematodes, Qitylgnchusgipsaci; the genus of 2. root-knot nematodes, Meloidogyne; citrus root nematodes, Tylenchulus semipenetrans, and to a certain extent also the causal agents of damping off. The usefulness and properties of chemicals used in partial soil sterilization are determined by: 1. Chemical composition and physical nature of steri- lant 2. Chemical changes which reduce toxidity 5. Toxic properties of sterilant 4. Leaching from the soil 5. Fixation of sterilant by the soil 6. Physical and chemical properties of soil The interaction of the afore mentioned factors affects the effectiveness of sterilants to control the soil-borne diseases and other parasites. The hardiness or immunity of some microorganisms or parasitic insects and animals to cer- tain chemical sterilants is a very important phenomenon and was given careful consideration by many researchers (55, 40, 42, 51). The toxic properties and effective time of duration of sterilant toward cultivated plants has likewise been studied. This study was primarily concerned with the retention in soil and the uptake of bromine by certain plants. The compounds which contained bromine were used in field and greenhouse studies on both mineral and organic soils. 3. The growth, deve10pment, and yield of certain craps in respeCt to the amount of bromine present in the soil, and the bromine present in plant tissue in relation to the compound of bromine incorporated into the soil, were studied. The amount of bromine in plant tissue at certain in- tervals of plant growth, and in plant parts,was studied. Certain varieties or strains of plants within a species may be affected differently by certain fumigants, therefore a further study is needed for investigation of the complicated phenomenon of biological-physical-chemical nature. LITERATURE REVIEW Kuhn (34) as early as 1881, used carbon disulfide for control of sugar beet nematodes, but without success. In 1911, Bessey (7) successfully used carbon disulfide against root-knot nematodes. Chloropicrin was used by 1920 while methyl bromide, as soil fumigant, was first used in 1940, and ethylene d1- bromide was used for control of nematodes in 1945. The investigation of effectiveness of soil fumigants in the control of nematodes and soil-borne plant diseases pregressed rapidly in the last 25 years. Many new fumigants appeared on the market, and the research on the effect of fumigants on soil as well as on certain species and varieties of plants has increasingly expanded. Coleman, 33 El. (13) reported that the soil treatment with carbon disulfide, ethyl alcohol, or toluene, when re- peated for three successiVe days, brought about complete sterilization without marked changes in the chemical consti- tution of soil. Dry heat induced only slight chemical changes, but the changes due to steam heat sterilization were Very great. Fleming and Baker (18) studied the movement of vapors of carbon disulfide in the soil. The diffusion of vapors was lateral and downward from the point of injection. Similar 5. results were obtained with several other soil storilsnts (25, 26, 55, 58). Allison (5) pointed out that the solubility of organic matter in the soil increased after sterilization with othy- lono oxide due to absorption of ethylene oxide vspors by organic and inorganic colloids. Howevor, the soil permeabil- ity or solubility of salts was not affected. Tho pH of soil increased appreciably. The reduced soil permeability and disintegration of aggregation was not duo to physical or chemical changes, but it was because of microbial cell growth and slimes or products of organic matter disintegration which tended to clog pores. Polyskov (52) reported the degree of penetration snd absorption of chlorine in sand. The sorption of chlorine in sand was proportional to the amount of organic mattor present. Chisholm snd Koblitsky (11) reported strong adsorption of methyl bromide by dry post. It was found that clay and sand absorbed loss of the mstorisl snd wot soil absorbed loss thsn dry soil. Fuhr snd Bransford (20) observed little or no absorp- tion of methyl bromide by sandy clsy containing 11 percent wster. This soil, however, sorbed markedly H25, 00012, HCN, and 802. Hanson snd Nox (25) found that the diffusion of othy- lono dibromido was slower both in soils with smaller poros snd thoso at higher moisture contents. Decomposition of 6. fumigant was 9 percent at pH 5.0 and 50 percent at pH 5.8. Similar results as to distribution and retention of the DD vapors in soils at different moisture contents were obtained by Schmidt (55), and with methyl bromide by Swank and Latte (63). Beames and Butterfield (5) attributed the wilting of tomatoes and spruces following the methyl bromide fumigation to the reduction of oxygen content of soil. The biological phenomena after soil fumigation was in- vestigated by many research workers. Fred (19) ascribed the increase in yield of plants which followed partial soil steri- lization by ether, carbon disulfide, potassium dichromate, copper sulfate, and Salvarsan, to biological phenomena. Stoklasa and Ernest (59) pointed out that the measure- ment of 002 evolution from the soil was a reliable and accu- rate index of organic matter composition and of bacterial activities in the soil. Waksman and Starkey (68) studied the biological ehanges in soil after partial soil sterilization with toluene or heat. Kincaid and Volk (31), Mattheus (40), Tam (64), and - BehOpolskyJ and Bershova (8) reported on different soil sterilants and their effect on soil biology. The fluetuation of soil microflora after soil sterili- zation with steam was reported by Katznelson (30). All organisms except Lzotobacter chroococcua inereased in number 7. after soil re-inoculstion and then steadily decreased to a certain level. Kincaid and Volk (32) reported effects of partial soil sterilization with DD and ethylene dibromide on black- shank, Phytophtore parasitic; var. nicotianae; root—knot, Meloidogyne spa., and coarse rot, as well as burning, forms of nitrogen content and yield of tobacco. Correlation of nitrogen with yield seemed to depend on moisture conditions. Ne effects of soil temperature and soil moisture were noted. Nettles (47) reported that continuous use of DD and ethylene dibromide as soil sterilants for five crops did not produce any harmful effect in sandy soils. Greater yields were produced during all years when all or part of the nitro- gen was in the ammoniacal form. Thomson and McLeod (66) reported no toxic after-effects in tobacco seedlings fumigated with methyl bromide at one pound per hundred square feet. Control of weeds and stimula- tion of growth was obtained. Similar results were obtained by other investigators (62). Many researchers were interested in the chemical changes occurring after seil fumigation. Among them, Russel and Hutchinson (53) described sterilization of .011 by 98° c heating, and 4 percent toluene treatment. The largest amount of ammonia was found in heated soil, and the next amount in toluene treated but evaporated soil. Still less was found in soil treated with toluene left in, and the least amount was in untreated soil. Chisevski (10) pointed out that the decomposition of organic matter in soil is considerably affected by the nature of base saturation of the organic matter complex. Sherman (56) ascribed the increase in yield following the soil sterilization in Hawaiian soils by chloropicrine and DD* to increase in availability of iron. The yields of plants increased as the ratio of the exchangeable manganese to exchangeable iron decreased. lillican (45) pointed out that some fungi compete with higher plants for maJer and minor elements. The release of P, K, Zn, In, and N occurred after partial soil sterilization. Oteifa (50) recommended increasing the potassium level for the plants infested with root-knot nematodes, Meloidegyne incognita. Miller (44) found that the nitrogen content ef peanut vines was not markedly modified by treatment with ethylene dibromide but that of roots and kernels was increased. . Scheffer (54) described the methods ef humus investi- gation with special emphasis on the biological phase of this problem. Norman (49) discussed the different theories on lignin, ligno-proteins, interaction of proteins with clay, colleids, and the different kinds of combinations of organic materials with organic colloids. Bear (6) discussed the relationship between eatien and *Dichloraproprame-Dichloroprepylene mixture 9. anion uptake by plants and postulated that there exists a constant ratio between the sum of m.e. of cations and the sum of m.e. of anions, irrespective of environment. Von Brausart (9) expressed the opinion that increased yield of crops due to partial soil sterilization with carbon disulfide or formaldehide was not solely because of destruc- tion of parasitic soil pests, but was also due to mobilize- tion and increase in solubility of Fe, Cu, E, Co, Mn, and Ni. Elreden (16) partially sterilized soil by flame heat, steam, and electricity, and received the best crop yields on soils treated with electrical current, next steaming, follow- ed by flame heating, and the least yield on unsterilized soil. He attributed the increase in yields to the killing of such harmful organisms as protozea, amebae, and ciliates. Feldmesser gt 2;. (17) described the quarantine and control of golden nematode, Heterodera rostochiensie, stating that in some sublethal treatments with both hot water and chemicals, there was a tendency for more larvae survival in winter cysts than in those of summer. McKeen (42) reported on the lethal effect of methyl bromide on microfloral components of a sandy loam compost soil. Fungi were destroyed at lower concentrations than were bacteria and actinomycetes. Methyl bromide not only freed vegetable seedlings from disease, but also increased their uniform growth. Lounsky (37) reported that Azalea plants fumigated in 10. vacuum with methyl bromide for two hours were not injuriously affected. Koch and Stover (33) obtained greatly increased growth of tobacco in soil fumigated with Dow N (DD), chloro- picrin, and Dow w-4o. Those fumigants also seemed to give promise in the control of brown—root-rot of tobacco. Allen and Raski (2) reported good results in the con- trol of nematodes, Pratylenchus spp., and an increased yield of strawberries was obtained after application of 15 gallons of CBP 55 (Technical chlorobromopropene 55%) per acre, in two applications, five days apart. A single application of DD at the rate of 40 and 80 gallons per acre was also effect- ive. Parris (51) has controlled root—knot nematodes, E232;- gdgra marieni, with DD, but not the damping off of spinach and pea seeds. Thorns and Jensen (67) used different rates of DD and ethylene dibromide (W-l5). The yield was almost three times higher with 400 pounds per acre of w-15 than with 200 pounds and nearly as much more as compared with check. Allen (1) experimenting on light sandy loam with carrots on DD and chlorepicrin fumigated plots found that all treatments gave higher yields and better stands comparing with untreated plots. DD applied at 200 pounds per acre, at 12-inch intervals was the most effective in the reduction of nematode population. 11. Dalton and Hurwitz (14) reported on soil steriliza- tion with formaldehyde, ethylene oxide, chloropicrin, chloro- form and HCN. Chloroform and HCN decreased the number of microorganisms but did not sterilize soil after 8 and 10 days of exposure, respectively. Possibly toxic concentra- tiens of cOpper and manganese resulted from the use of ehlerepierin. Middleton, gt g1. (43) reported that the application of_fumigants to the soil supporting lima beans, reduced the injury index of root-rot. Stone (61) reported good control of delfinium nema- todes, Pratylonchus pratensig, by fumigation of soil with either methyl bromide er DD. One-half percent chlorophenel or 2.5 percent cresylic acid solution was not as effective as the former. Ingham, £3 21- (27) indicated promise of pest control by chlordane, BHC, DDT, Toxaphene, and ethylene dibromide without marked disturbances of natural balance of soil fauna. McClellan (41) reported the results of soil fumigation with Dowfume W-4O (EDB), and DD in control of both meadow and root-knot nematodes in tobacco, Iscobrane D (EDB), chloro- picrin and methyl bromide were effective in meadow nematode control. Dowfume 40 did not control nematodes of onions. Grainger (24) described the effective control of - potato-root eelworm, Heterodera rostochiensis, by soil fumi- gation with DD. Ethylene dibromide and methyl bromide 12. prevented building up of cysts. Lear (35) reported that ethylene dibromide, methyl -bromide, dichleropropene and chlorepicrin were effective nemateicides, and controlled or retarded also the following fungi: Fusarium, Pythium and Plasmodiephora brassicae spp. However, Lear, gt 3;. (36) reported that ethylene dibromide was not effective in control of golden nematodes on potatoes. Similar conclusions about the control of nematodes by ethy- lene dibromide were obtained by other investigators (41). Cockbill (12) pointed out that soil fumigation with "Shell DD" or ethylene dibromide, at a depth of 9 inches, was very effective in controlling root-knot eelworms on heavily infested soils. Mai (38) reported that methyl bromide up to 60 pounds per 100 cubic feet, for 16-20 hours of exposure, at 22.2- 26.7' c was ineffective in killing either Corynebacterium sepedenicum er Fusarium sambuciggg, Stover and Koch (62) pointed out that under Ontario conditions, methyl bromide at 2 pounds per 100 cubic feet destroyed all soil-borne tobacco pathogens. Elimination of damping off fungi and weeds was obtained at less than one pound of methyl bromide per 100 cubic feet. Williamson (69) reported on injury of carnations caused by previous soil sterilization with methyl bromide. The plant injuries were roughly proportional to the total colloidal content of the soil, the soil temperature, and the 13. amount of methyl bromide applied. Methyl bromide can be used to sterilize pure sand if it is free from pest and other organic matter. Newhall (48) reported the injuries of cuttings of Bennafan DcLuxe Chrysanthemums by fumes of Iscobrome (methyl bromide mixture). Other varieties were not affected. Minz and Palti (46) doubled yield of cucumbers and tomatoes by applications of calcium cyanamide, ethylene di- bromide and DD for the control of nematodes. Graham and Heldeman (23) described the effective con- trol of sting nematode, Belanolaimus:gracilis, in cotton and other crops by use of ethylene dibromide or DD at specified rates. Martin (39) reported destruction of citrus-root noma- todos, Tylenchulus scmipenetrans, in orchard soil by injections of DD, ethylene dibromide, or chlorepierin in certain dosages into the soil. The yield of citrus replants increased greatly. Soil structure was not changed, but water soluble Ca, Mg, K, and Mn were temporarily increased. I. EXPERIMENT I --MICHIGAN STATE COLLEGE FARM METHODS AND PROCEDURES The experiment was set up to study the water extract- able total bromine in the soil and the amount of total bre- mine present in plant tissue at different intervals of plant growth, after the soil was treated with different carriers of bromine. The soil used for this experiment was Hillsdale sandy loam, located on the Michigan State College Experiment Farm, East Lansing, Michigan. The pH of the soil was 6.4, and it contained 1.92 per- cent organic matter. The soil was plowed in early spring, fertilized with 180 pounds of 20-0-0; 290 pounds of 0-45-0; and 365 pounds of 0-0-20 per acre, on May 27, 1953, and it was finally prepared for planting on May 29, 1953. The soil plot in the size of 12,000 square feet was divided into 16 equal plots, 50 by 15 feet, and four complete- 1y randomized treatments were carried out. Six crops were grown on each plot. All treatments and crops were replicated four times. ~ The following fumigants were used for the treatments of soil: 1. Dowfume Mc-2, 98 percent methyl bromide with 2 percent chloropierin. l5. 2. Dowfume W-85, EDB, 85 percent ethylene dibromide in an inert solvent. 3. Sodium bromide salt, NaBr. 4. Check, no treatment All fumigants were applied to the soil on May 5, 1953. Methyl bromide was applied under plastic cover, remaining as for 24 hours; ethylene dibromide by field applicator, and sodium bromide was broadcast and disked into the soil. The following amounts of fumigants were used on the more basis: (a) Mc-2, 435 pounds equivalent to 370 pounds of bromine (b) w-85, 9 gallons equivalent to 160.5 pounds of bromine (c) NaBr, 475 pounds equivalent to 370 pounds of bromine At the time of soil treatments the soil temperature was 640 F, air temperature 780 F, and soil moisture was 12 percent. Potatoes, onions, carrots, and peanuts were planted on May 29, 1953; beans, Black Valentine variety on June 8; and cabbage on June 24, 1953. Because of very poor stands of onions and carrots due to drought, they were excluded from experimental observations. Observations of growth and yields were recorded. Cabbage and bean plants were sampled and analyzed for total bromine according to the following schedule: 16. Ag, Cabbage plants B. Soils 1. July 23 July 1 2. August 13 July 23 3. September 4 August 13 4. September 24 September 4 5. - September 24 C. Bean plants 2. Bean pods E. Soils 1. July 14 - July 14 2. August 4 August 4 August 4 3. August 25 August 25 August 25 4. September 15 September 15 Sept. 15 The soil was sampled at random to a depth of 10 inches, ten samples from each plot, mixed thoroughly together, and a representative sample was placed in a plastic bag and sealed. Later on it was screened through a 2 mm. screen and analyzed for water soluble bromine. Plant samples were taken at random, 5 plants from each plot, dried at 1600 F for 12-24 hours, ground, stored in bottles, and analysed for total bromine. The whole cabbage plant with roots was analyzed. The first analyses were on whole bean plants. Thereafter the pods were removed and analyzed separately. The method used for the determination of bromine in plant tissue and in soils was that described by Shrader, gt 2;. (57). Five gram samples of plant tissue and that of 17. soils were employed in this investigation. A slight modifi- cation of Shrador's method was used for water soluble bromine in soils. The five-gram portion of soil was leached with three 50-ml. portions of distilled water. The leachate was slightly acidified, then neutralized to the color change of methyl red indicator and analyzed for bromine according to Shrader's method. Method for Determination of Total Bromide A five or ten-gram portion of plant tissue or soil sample was placed in a 100 ml. nickel crucible and treated with alcoholic potassium hydroxide (2.5 gm. potassium hydro- xide per 100 ml. 95 percent ethyl alcohol). After one hour the soil was dried on a steam bath. After that it was dried on a hot plate for a short time and covered with 10 grams of sodium hydroxide pellets. The crucible remained on the hot plate for one to two hours and then was transferred to a muffle furnace at 600° C. Care was taken that the samples were completely dry before they were placed in the furnace. Fusion should be completed without excessive burning or foaming. The sample was kept in the furnace until the vela- tile gases were removed (4-5 hours forplants and 5-5% hours for soil samples). Sodium peroxide was added to the sample, a few milligrams at a time to accelerate the oxidation of organic matter. The sample was removed from the furnace and the sodium peroxide added cautiously. If the sample burned 18. with a glare the bromide was lost. Complete combustion of organic matter was attained by rotating the melt and returning organic matter to the bottom of the crucible, then adding 0.5 gram more sodium peroxide. The crucible was then returned to the furnace. The combus- tion was complete when no bubbling or burning occurred. The accuracy of results was not affected by the few carbon parti- cles which remained undigested after the addition of sodium peroxide. Samples were removed from the furnace, rotated to allow melt to solidify on the crucible sides, cooled, and dissolved in 75 ml. of distilled water. When dissolving was slow, the samples were placed on a hot plate for a few minutes. The solution was transferred from the crucibles to 400 ml. bear kers and partially neutralized with about 50 ml. of 6 N bromine free-hydrochloric acid. After that the solution was boiled to destroy peroxides and reduce the volume to 100-125 ml. The solution was then filtered through a No. 2 Whatman filter paper in order to remove nickel and other insoluble hydroxides, and the filtrate and washings were transferred to a 500 ml. Erlenmeyer flask. The filtrate was slightly acidified with 6 N bromine free-hydrochloric acid and neutral- ized with sodium hydroxide to the color change of methyl red. At this point the volume of solution was about 150 ml. Two grams of monobasic sodium acid phosphate and 5 ml. of 0.1 N hypochloride solution (Na0C1 or KOCl) were added, 19. and the solution was heated to boiling. After one minute boiling 5 m1. of sodium formats solution (50 g. per 100 ml. water) was introduced and boiling continued for 2 minutes. The sample was cooled and treated with a few drops of l per- cent sodium molybdate solution, 500 mlgrms. of potassium iodide, and 25 m1. of sulfuric acid. Immediately the sample was titrated with 0.01 N sodium thiosulfate solution. Starch indicator was added just before the end point (fading of greenish color of solution) was reached. A blank on all re- agents was carried through the entire procedure. Appropri- ate corrections were made. One milliliter of 0.01 N thiosulfate was equivalent to 0.1332 milligrams of bromide ion. 20. Experimental Results and Discussion Cabbage Unfortunately, 1953 was a dry year, especially during the first part of the summer, thus the cabbage plants did not show expected vigor in growth. The best looking plants were on untreated plots and on those treated with W-85. Plants treated with Mc-2 were not so good and those treated with sodium bromide were poorest. The plots were not infested by nematodes or other parasites, therefore the increase or decrease in growth and yield of cabbage was attributed to the effect of the parti- cular fumigant under the environmental conditions of this experiment. The bromine content in the tissue of treated plants was the highest in the samples of July 23, 1953, decreasing rather rapidly so that at the second sampling, on August 13, the bromine content was roughly one-third of the previous amount. The samples takemeeptember 4 and 24 decreased steadily, but rather slowly in bromine content. The content of total bromine in plant tissue and the differences for significance are shown in Table l. The highest amount of water extractable bromine in the soil was found in the first samples from the plots treated with sodium bromide, the next amount was in the soil which received methyl bromide, and the least amount in treated soil was in that receiving ethylene dibromide. The lowest PPM TOTAL BROMINE IN CABBAGE PLANTS FROM MINERAL SOIL, MSG FARM, EAST LANSING* 21. TABLE I. Treatment Dates of Samplings July 1 July 23 August 13 September September 4 24 Mc-2 - 1130 338 274 227 W-85 - 830 268 179 166 NaBr - 993 387 268 177 Check - 166 165 118 87 L.S.D. 5 percent 272 117 106 153 1 percent 391 169 153 220 *All data averages of four replications of oven dry material TABLE II PPM WATER EXTRACTABLE BROMINE IN SOIL FROM CABBAGE PLOTS, MSC FARM, EAST LANSING Treatment Dates of Samplings July 1 July 23 August 13 September September 4 24 Mc—2 38 12 22 12 7 W—85 24 8 18 10 5 NaBr 64 43 40 l7 14 Check 8 4 7 5 3 L.S.D. 5% 27 13 12 5.5 2 1% 39 18 17 8 3 22. amount was in the untreated soil. With time the water ex- tractable soil bromine decreased gradually and the differ- ences among the individual treatments changed from time to time, as shown in Table 11. Yield of cabbage was the highest on W-85 treated plots. Yields decreased in order on untreated plots, those treated with Mc-2, and were least on NaBr treated plots. (See Table VI.) It seems that the presence of a considerable amount of water extractable bromine in the soil during the period of plant growth tended to depress the uptake of anions. This reduced absorption depressed the physiological plant processes, especially at the early growth stage, because of the toxic properties of the bromine (6). However, the de- pressien may be also partially due to lack of oxygen, because the introduced sodium in sodium bromide treatment resulted in the formation of a compact layer on t0p of the soil (5). Beans The growth of bean plants was very slow at the beginning of the experiment, but improved slightly after a few rain showers. Neither Mc-2 nor NaBr treated plots sup- ported bean plants properly. A few light rains in early August induced vigorous growth on all plots, especially those treated with Mc-2 and NaBr; however, they were not able to catch up with the comparably better appearing and 23. growing beans on W-85 and the check plots. The examination of roots showed that the best develop- ed roots were from plants grown on w-85 treated plots, next and almost equal sized roots were from plants on check and Mc-2 plots while very poorly developed roots were found on plants on NaBr treated plots. The highest content of total bromine was obtained in bean plants from NaBr treated plots. The plants from the check plots contained the least bromine while those from the other two treatments were intermediate and in order of Mc-2 and w-es, respectively. As is seen in Table III, the amount of bromine in plants sampled on July 14 and August 4 decrea- sed rather little, but samples of August 25 and September 15 showed rapid decrease in the amount of bromine in plant tissue from all treated plots. The bromine contents of un- treated plants did not follow the same pattern. The content of total bromine in bean pods was lower than in bean plants. The amount of bromine as related to different bromine carriers is shown in Table V. Between: August 4 and August 25 the bromine content of bean pods in- creased slightly in plants treated with NaBr and Mc-2 and then decreased rapidly. 0n the other hand, the bromine con- tents of bean pods from the W-85 and check plots decreased consistently as the season progressed. The water extractable bromine content of the soil is Presented in TableIV. There was a smal) fluctuation of 24. TABLE III PPM TOTAL BROMINE IN BEAN PLANTS FROM MINERAL SOIL, use FARM, EAST LANSING Treatment Dates of Samplings July 14 August 4 August 25 September 15— Mc-2 828 832 586 228 W-85 585 523 469 184 NaBr 929 873 461 170 Cheek 165 243 394 182 LSD 5 percent 193 211 266 65 1 percent 277 303 382 93 TABLE IV PPM WATER EXTRACTABLE BROMINE IN SOIL FROM BEAN PLOTS, MSC FARM, EAST LANSING .— ‘ IV' Treatment 4 Dates of Samplings July 14 August 4 August 25 September 15 Mc-2 30 23 25 12 W—85 17 11 16 5 NaBr 50 63 83 25 Check 15 10 9 6 LSD 5 percent 23 10 21 1 percent 33 14 30 10 25. TABLE V PPM TOTAL BROMINE IN BEAN PODS FROM MINERAL SOIL, MSC FARM, EAST LANSING Treatment Dates of Sampling August 4 August 25 September 15 Mo-2 524 570 116 W-85 602 474 33 NaBr 666 699 128 Check 389 242 55 LSD 5 percent 207 115 70 1 percent 298 165 100 TABLE VI MEAN YIELDS OF CROPS OF FOUR REPLICATIONS FROM MINERAL SOIL, MSC FARM, EAST LANSING Treatment Cabbage Beans Size of Heads in Size of Seeds Plot pounds per Plot Grams per Sq. ft. Plot Sq. ft. Plot Mc-2 75 34 50 82 W-85 75 44 50 237 NaBr 75 27 50 81 Check 75 36 50 225 LSD 5 percent 10.0 54.0 1 percent 16.7 77.5 26. water extractable bromine at different times of sampling which was almost linear in the Mc-2, and W-85 treated soils. Sodium bromide treated soils showed a considerable accumula- tion of water extractable bromine in the samples of July 14 to August 25 with a rapid linear decrease later on. This phenomenon is a rather interesting one, but cannot be ex- plained without further investigations. Yield of bean seeds was the highest on W-85 treated plots, next on check plots, and low and almost equal on Mc-2 and NaBr treated plots. (Table VI.) From the data of this experiment it appears that an amount of bromine closely approaching or exceeding 1,000 p.p.m. in the dry tissue of Black Valentine bean plants at the early stage of growth depressed development of the plants. Potatoes and Peanuts Potatoes were not detrimentally influenced by bromine treatments of soil. These plants showed good general appear- ance and growth irrespective of treatment. However, the plants from NaBr treated plots showed slight browning of leaf tips, especially when dry and hot weather prevailed. The highest yield of potato tubers was on Mc-2 treated plots, next highest on W-85, next on the check, and slightly lower on NaBr treated plots. The data in Table VI show the yield of potatoes as affected by different soil 27. treatments and the significance for difference at the 5 and 1 percent levels. Peanuts showed rather progressive growth as a result of treatment with W-85 or where the soil was untreated, a little slower growth on Mc-2 treated plots, and a stunted growth on the NaBr treated plots. These differences in growth and development continued throughout the season. The peanut plants from the NaBr treated plots exhibited a yellow- ish appearance, and the leaves turned brown by the first small frost, whereas plants from plots receiving other treat- ments were not frosted. This indicates that the physio- logical system of plants from NaBr treated plots was upset. Peanut yields were highest on W-85 treated plots and least on those plots which received NaBr. They were inter- mediate and about equal on untreated and Mc-2 treated plots. The very significant increase in yield due to w-cs treatment, and the significant depression in yield due to NaBr treatment are shown in Table VII. 28. TABLE VII MEAN YIELDS 0F CROPS OF FOUR REPLICATIONS FROM MINERAL SOIL, MSC FARM, EAST LANSING Treatment Peanuts Potatoes Size of Peanuts Size of Tubers Plot Pounds per Plot Pounds per Sq. ft. Plot Sq. ft. Plot Mc-2 90 10 135 47 w-es 90 13 135 45 NaBr 90 8 135 30 Check 90 10 135 33 LSD 5 percent 1.06 6.77 1 percent 1.53 9.52 EXPERIMENT II.--MICHIGAN STATE COLLEGE MUCK FARM METHODS AND PROCEDURES In the spring of 1954 an experiment was set up on Houghton muck and Brady loam on the Michigan State College Muck Experimental Farm, Clinton County, to study the growth and yield of table beets and beans as affected by two different carriers of bromine. The retention of bromine by these soils was also considered. The pH of Houghton muck soil was 6.3 and this soil contained 82.6 percent of organic matter and 17.4 percent of ash. The pH of Brady soil was 6.7 and it contained 4.6 per- cent of organic matter. Both soils were plowed, cultivated and harrowcd in spring to prepare the seedbed. The Houghton muck was ferti- lized with 1,000 pounds of 0-10-30 per acre and the Brady with 1,000 pounds of 12-12-12. Three treatments of soils were used: 1) Methyl bromide (Mo-2); 2) Ethylene dibromide 85% (W-85); and 3) Check. All treatments were replicated four times. Methyl bromide was used in the amount of 435 pounds per acre, corresponding to 370 pounds of bromine, and ethy- lone dibromide, 9 gallons per acre corresponding to 160.5 Pounds of bromine. 0n the muck soil 12 plots were prepared and also 12 on mineral soil. Each plot was 48 by 12 feet, covering an 30. area of 576 square feet. 0n the mineral soil each plot was subdivided for two crops, beans and table beets. Eight out of 12 plots on muck soil, and 16 out of 24 plots on mineral soil were to be treated by either methyl bromide or ethylene dibromide. Ethylene dibromide was applied by field applicator on May 26, 1954, and on the same day only two plots were treated with methyl bromide. The remain- ing plots were treated, two at a time, on May 28, June 1, and June 4, 1954. The soil moisture at the first treatment on May 26 was 11 percent and 62 percent, and soil temperature was 24' c and 21° C for Brady and Houghton seile, respectively. The methyl bromide fumigated plots remained under cover for 48 hours. After all treatments were accomplished and the plastic covers removed from the last plots, all treated plots were aerated by means of cultivator and beans and table beets were planted on mineral soil and table beets on the muck soil on June 15, 1954. The beet plant seedlings on Houghton muck soil suffered damping off, and therefore a half of each plot, ir- respective of treatment and damage, was replanted on July 7, 1954. During the growing period two samplings of soils and plants were made. The first sampling took place on August 19 and second on September 25, 1954. Six plants were sampled from each plot, dried for 12-24 hours at 160-170° F 31. (beets were sliced and dried slightly longer) stored in tightly covered bottles and analyzed for total bromine. Only beet roots and bean pods were analyzed. Sampling of plants was performed in completely random- ized order while that of soil was from ten places directly in the plant rows. Soil samples were cores to a depth of ten inches. The soil samples from a certain plot were thoroughly mixed, air dried, screened through a 2 mm. screen and again mixed. A representative sample was then preserved in a closed container. The plant tissues as well as the soils were analyzed by the method described by Shrader, at 21° (57). The samples used were 5 grams in weight. Because the fresh soil samples were not analyzed immediately, but were air dried, the water extractable bro- mine gave low values, and was decided as not reliable. The determinatiens should be run on fresh soil samples. The yields of table beet roots and bean seeds were recorded. For the sake of a comparison of quality the beets were graded as follows: (a) Large, larger than 2% inches in‘ diameter; (b) Medium, 2-2% inches; and (c) Small, smaller than 2 inches in diameter. 32. EXPERIMENTAL RESULTS AND DISCUSSION Beet seedlings grown on W-85 treated Houghton muck were badly affected by damping off. No damping off occurred on the soil treated with Mc-2 but some did occur on the un- treated muck. No visible differences in growth and general appear- ance of beans and beets were observed on the mineral soil plots on July 27, 1954. On the muck soil, however, there was a vigorous growth of beets on the Mc-2 treated plots, a less vigorous growth on the check plots and a weak growth on the W-85 treated plots. On the other hand, observations on the muck soil on August 19 showed the most vigorous growth and darkest green color of beets to be on W-85 treated plots with the next best beets on the check plots. The beets frem Mc-2 treated plots were starting to show symptoms of nitrogen deficiency at that time. The nitrogen starvation may be ex- plained by partial exhaustion of readily available nitrogen by the rapidly growing plants in a vary good stand, and also partially by a tie-up of nitrogen by speeded multiplication of soil microorganisms (30). On some of the Mc-2 treated plots in the spots where the Mc-2 gas was distributed, there were visible signs of stunted growth and curling of leaves, presumably due to high bromine content in the soils in these areas. The soils and plants from these spots were analyzed separately and the 33. data are presented in Table XI. Such spots were present only on the muck soil. The total bromine contents of beet root tissue from the mineral soil samplings of August 19 were the highest in plants from Mc-2 treated plots, followed by that of plants treated with W-85, and were the lowest in plants from check plots. In the second sampling the plants from the W-85 treated plots were the highest in the content of bromine, next were plants from Mc-2 plots, and the lowest content of bromine was in plants from check plots. The amount of bromine in treated plant tissue, from the first to the second sampling, diminished roughly by one third. Table VIII shows the amount of bromine present at different samplings and the differences for significance. The total bromine content of mineral soil from beet plots on August 19, 1954, was the highest from.Mc-2 treated plots, next from those treated with W-85, and lowest where bromine was not applied. A similar gradient was obtained with the soils from second sampling. The second sampling showed slightly lower bromine values than the first one. No significant treatment difference in the amount of total bro- mine was found in the first soil samplings, and only the bro- mine in the check soils was significantly lower in the second sampling, as is shown in Table VIII. 34. TABLE VIII. PPM TOTAL BROMINE* IN SOILS AND BEET ROOTS FROM BRADY LOAM SOIL, MSC EXPERIMENTAL MUCK FARM, CLINTON COUNTY, MICHIGAN Treatment Dates of Sampling .1 Soilg Eggt zgotgw_ August 19 September August 19 September . 2.5 __ 25 __ Mc-2 107 94 951 630 W-85 79 75 837 655 Check 49 43 120 102 LSD 5 percent 32 26 115 181 1 percent 48 40 174 273 *Means of four replications 35. The yield of table beets on mineral soil was not sig- nificantly affected by treatment. The highest yield was on W-85 treated plots while the lowest yield occurred where Mc-2 was applied. However, there were differences in the quality of the beets. The medium sized table beets have been considered the best seller. The highest percentage of medium sized beets was on W-85 treated plots (69.25%), the next highest on Mc-2 treated plots (67.75%), and the lowest on the checks (58.75%). The higher percentage of medium sized beets on plots treated with bromides can be attributed to the immediate availability of plant nutrients in the root spheres at the early growth stage and thereafter, thus all plants had the same chance for growth and competition (9, 39). The amount of total bromine in the table beet tissue of plants grown on Houghton muck soil was highest in plants from Hc-2 treated plots, next highest where treatment was W-85, and the lowest where bromine was not applied. A similar picture with total bromine was found in the soil. All treatment differences significant at the 1 percent level are shown in Table IX. The yield of table beets on Houghton muck soil was the highest on Mo-2 treated plots, next highest on check plots, and lowest on W-85 treated plots. The low yield on W-85 treated plots was due to the reduction of stand by the damping off fungi. The quality of beets was, in decreasing order: (1) Me-2 treated plots - 75, and 20.75 percent; 36 TABLE IX PPM TOTAL BROMINEfi IN SOILS AND BERT ROOTS FROM HOUGHTON MUCK SOIL, MSC EXPERIMENTAL MUCK FARM, CLINTON COUNTY, MICHIGAN Dates of Sampling_ Soils Bean Pods Treatment ”— """" 4* August 19 September 25 August 19 September 25 Mc-Z 1&8 1A8 936 803 WSBS 88 83 6A6 60h Check 33 33 139 105 LSD 5 percent 31 3O 83 113 1 percent h? #5 126 ' 170 .——___ * Means of four replications TABLE X YIELD or CROPS ON MSC EXPERIMENTAL MUCK FARM (MEANS or FOUR REPLICATIONS IN POUNDS) liggghton Muck Brady Loam Table Beets Table Beets Bean Seeds Treatment For Plot 576 Per Plot 288 Per Plot 288 Square Feet Square Feet Square Feet Mc-Z 5&3 293 103 ‘Hb85 388 305 108 Check 503 301 103 LSD 5 percent 131 73 9.h2 1 percent 198 110 lu.27 37. (2) Checks - 57.50 and 37.50 percent; and (3) W-85 treated plots - 24.75, and 73.50 percent of medium size and large size, respectively. The high amount of large size beets from plots treated with W-85 was due to greatly reduced stand by early damping off. Table X shows the yield of table beets. In Table XI is shown the bromine content of table beet tissue from the spot where the depressed growth occurred, four feet apart, and from the plot as a whole. It is seen that 975 ppm in the plant tissue and 186 ppm in soil found on September 29, 1954, caused depressed development of beet roots, and the leaves were curled, deformed, and more inten- sively brownish-red colored. The total bromine content of bean pods from mineral soil sampled on August 19 was the highest in plants taken from Mo-2 treated plots, next in those treated with W-85, and lowest in plants from check plots. This can be seen in Table XII. The second sampling on September 25, 1954, showed the diminution of total bromine in bean pods to be roughly about one-half in those taken from the bromine treated plots with only slight decreases in those from check plots. All differ- ences in the total amount of bromine were significant at the 1 percent level as shown in Table XII. The highest amount of bromine in the mineral soil from bean plots was in that treated with Mc-2, next in that 38 nsoflpoo«wmon snou_uo once: o odd , dam em 0: encased H no oom NH om accused m emu be mod N: mm . noose SN 23 I: E moi :m: com os mo mnos mm aoQSopmom ma posmd< mm sensopnom on posms< mood zoom mason scossaoca wsaamadm Ho woven 240Hm0H: .NBZDOO ZOBZHAU .2m4m moDzHA