N “I l. 0| H | — ,— ,_- — — — — — — .___'—.n , , — — i —4\]_s I000 (JDLOO 1 . ‘ WV») ’IAF‘U 1" ' I" r‘ ‘ {‘ 4 a . d “ {‘1 ~ . o l ' x Q J. r ‘ A ‘ _.‘V ‘ ;‘. 2. § ‘ k f.‘ k E \ g. > t . ‘ ‘fi. 3.} 3 rd - . r ‘ i g ‘ ~ - ,f -. ‘11: .4\." I A X it \w I s . a K; i 3 “an. ' ‘ a, "'«c: i * , a; \..r I‘i- A S a n t l 4‘ 8 NJ" .5. s 7 . 'T‘hesis {or The Dagrea 01'- M. S: :WCH.IG§1M~£ STATE COLLEGE :53‘éaul S. Andrews 7. 951 —— -—-r .w- Date This is to certify that the thesis entitled THE INFLUENCE OF TEM‘?ERATURE ON THE FLOWER BUD INITIATION OF CHRXSANTHEMUM MORIFOLIUM presented by PAUL S .ANDREWS has been accepted towards fulfillment of the requirements for _M.S._ degree in WLT URE 39 M PMOW DONA ”2‘. “$3851 JUNE 1951 _.._‘ . ., J. 4 er "-7-" .-' f r V'— V 7— ’ -F- *an- ;' ' l‘ 7_‘ V b of I ._ . - -‘n... -‘m-h‘--:o - _‘. -N -...L .— -. .‘t.-- - an - I h‘ "17"? an . .J ‘_n . - CT “T"“fiW‘Tvflf PU TKO??? 7V9 TvTTIJmTF" .‘.J .4. .c-'. . l.’_ "r 1 AIWW’YT'N'YW’ lbw-V?“ 'r-rr 1’ C, 3 m l. OJJLJI . . - a L.’_.i' ..--.~5 “Jr . .ku-.l J. r q mvrhn‘t'rt :1 L .;:._r);_.) J" -. ls; and flpjlied Science in cartial fa fillnent 1 , C a ‘ ' 'V\ A ! I Q 4- 1H M PQQilTEMLRDS for cue cevree of rnflm"_ 1-: on m'rnfi 1%»ij Cl' LJUI.:1.‘u...J Department of Horticulture 1951 n - fin- , run .1- , :- 1r'.1_-_' “H. (U. ,. Cu. C‘rga-uto _.a...,1(.,.1 s O. Jfi=‘;.,.u.g;1 J fin 00112;.”9 THESIS? f‘ i“?*‘? T VT WNW 7"” "'71 : _'.u it.) Jinan“; The author wishes to QXpress his gratitude to the foilowin; persons: Dr. Donzld P. U tsnn, for his ca;- dble a:cist;nce, helpful suCQQCtions, find untiring pat- ience; Eartha stiflson, for techni011 :ssistance; vid Vision ‘errobt, for _i9 in OItMLJ'Wp “cb‘ltiCl miter- i317. TL“ fiuthor else ";?hcz to effresc his :pjracist- 4.1.. H '-.,, "-1-. T3! .',,~!. .. ~- ~ ' . 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DEL? fer~ .% r. cv-s ‘ l‘r r. q" A: a), r‘ ‘ ' ‘L ‘r . /-.M.' \ 1.hcry o; flo.ur pytd Lécmc 20 “103° gigs v ...’,,. - .L -n v, . W:~0+ 0T4 H CMOU ’ol‘lrl ~11 cf :L'illu'r:1~ S LS'IFS of 4.1L' CJ— 1 ¢ 9‘ 5‘ .r- n wvA A ~’ 10 -ri- 0“r11g err1top-ce1'ter of LlOmur he: 1 “3-® ... -- .U _,L 3, H . 0 Kean dEJ ten ergtures Lfl p0 39d 60 F. ,. ~\‘— ("5" UTQCI' C'1“1"I"*-“-‘ ........’P.r..............9..‘fll ~ on t. p.\. \,’ r 2-: -.1_...L "' “1-7 11,14- 1-. r- .) Clo ., A? rolfi'fi 1.0 11 Inidnka te-;>e.;.uu.<3s 3-1 ;.1 ,IM. w 4:. A ,- {,I'LB’LJIMOIISQS 00090000000090-ooOOCQQOOOOOOOOQOO'OO'1'! T1 - A J. .. r- .L‘l .n' .. . .. A- elemwr st: 3 Lrom ”he LlTSt gr,c31:m1:e crop v“ fin r [I r 1 “ ”’7‘ 4' \-F‘ I‘ .‘ Lt )0. --‘.LL (/0 .L. V31”; I'-Lt'.>--.’3 ooooooooooooooooooonvoo ‘0 ‘J b) 1 -0 1 I“) b.) ‘ r I n , 1 )v \ fl . -I o o D o .141 O \ U $ t ”I a n - r A ,— 5 w . - r '- L‘ a Q m I P - u u- \ Q 7 n H I- 3 ~ '1 s ‘\ IWTRCDUCTION The effect of temnerature on flower bud initiation of Chrvsa - A +— V- thehum morifoliun has not been investigated as completel; as the effect of daylength. As early as 1920, Garner and Allard showed the effect of daylength on flower formation of several plants. Since that time Tincker (1925), Poesch (1931), Post (1931), and oth- ers, have established the Specific effect of daylength on Chrysan- themum morifolium. Flower buds will initiate if the dark period is at least lh% hours long provided the temperature is SSOF. or high- er. Growers are being advised that a minimum temperature of 60°F. must be maintained to insure bud formation and rapid growth of the Chrysanthemum (Post 19h9). Kiplinger and Hasek (l9h9), reported that the best growth and flowering resulted in the pompon varieties: Golden Herald, Little America, Masterpiece, and Bronze Masterpiece, when the night temperature was maintained at 60°F. except during the period of flower bud initiation, for which they recommended a night temperature of 65°F. Post (1939), grew the variety Copper City both in a refriger- ator at 50°F. and in a room where the temperature ranged from 75°F to 85°F. The plants in the refrigerator were lighted with incandes- cent lights hung 3 feet above the plants. The intensity of illum- ination at the tip of the plants averaged 300 foot candles. The plants in the 75°F. to BSOF. greenhouse received the normal daylight illumination found in Ithaca, New Ybrk during the early summer mon- ths. Post believed that data tabulated from this experiment showed that higher night temperatures hastened bud formation and increased the number of buds per plant. The low night temperatures were thought to cause fewer buds to form but larger flowers developed from those that did form. Post stated, "The low light intensity doubtless af- fected this budding." Chrysanthemum growers in central.Michigan have observed many "blind Sheets" on crops initiating flower buds during the early fall months when accurate night temperature regulation in the greenhouses was not in effect. Since it was thought that the night temperature at this critical initiation period might have a definite effect on the resulting crop and the misting information on temperature in~ fluences was not too comprehensive, the present eXperiment was de- Signed. REVIEW OF LITERATURE Influences of davlencth: Post in l9h2, observed that greenhouse varieties of Chrysanthemum normally start forming flower buds from August 15th to 25th in the latitude of Ithaca, New Yerk. The method for determining this date consisted of shortening the day length on several plots of Chrysanthemum plants at ten day intervals, prior to the estimated date of flower bud initiation, and then comparing the flowering dates with similar plants, grown under normal daylength conditions. The plants which produced flowers at the same time as those grown under normal daylength conditions were assumed to have been shaded at the date of normal flower bud initiation. Post observed vigorous vegetative growth on Chrysanthemum plants from April lst to August 20th. After flowering, they became dorm- ant and grew only slightly during the winter. He postulated that this dormancy was the result of low light intensity, low temperature, short days, or an interrelation of all three. Anatomical studies were made of Chrysanthemum plants, variety Silver Sheen, by Link, 1936. These plants were grown from rooted cuttings potted May 30th. Beginning July 20th the photOperiod was reduced to 10 hours per day on one half of the plants. This short day treatment was continued for 22 days at which time the terminal buds averaged one—fourth inch in diameter. The terminal buds on b) r‘v. the plants grown with normal daylength averaged one-fourth inch in diameter on September 2lst. While Linn did not explain his tech- nique of bud examination, he concluded from his anatomical studies that the growing point changed from a vegetative to reproductive state within 8 to 10 days after short days were begun. Influence of temperature: Comparatively little information on the specific effect of temperature on flower initiation has been reported. Experimental work with Xanthium.by Hammer and Bonner in 1936 indicates that the temperature during the dark periods greatly influences the initiation of flower buds. One long dark period with temperatures of 2100. to 320C. resu ted in flower bud formation. If the-temperature was maintained at hOC. or lower, seven long dark periods were required to achieve the same results. Namner and Bon- ner further state that "In contrast to the striking efiect cf vary- ing the temperature during the dark periods, varying the tempera- ture during the photOperiods exerts little effect on the initiation of floral primordia. Although low temperatures during the photo- period was without significant effect on the initiation of floral primordia, there was marked decrease in the subsequent rate of de- velopment of the princrdia." These results led them to theorize that the reaction leading to the rmnufacture of floral initiating substance was adversely affected by low temperatures during the dark period. A later report by Bonner in 19h? stated that a night t mpera- ture below 60°F. was unfavorable to flower bud formation in the Camellia varieiy “ink Perfection. Post (l9h2), feund that at the latitude of h2°N., vegetative growth in Chrysanthemums started before April lst at SOOF. but no flower buds were initiated. He attributed this to low temperatures. Substantiation of this belief lies in the behavior of plants which initiated flower buds when grown with a night temperature above 60°F. during the same period. Anatoqz'gf flower bud initiation: The anatomy of stem apexes has been studied on many plants: Glycine ussuriensis, Borthwick and Parker (1938); Phlox drummondii, Miller and‘wetmore (l9h6); Bellis perennis, Philipson (l9h6); Succisa pratensis and Dipsacus fullonum, Philipson (l9h7); Hieracum'borcale and Dahlia gracilis, Philipson (l9h8; and Chrysanthemum morifolium, Chan (l9h9). Because of the composite structure of Bellis perennis, Philip- son's work with this plant is more applicable to the Chrysanthemum than most work and warrants closest scrutiny. He described‘the transition of the stem apexes from the vegetative to the reproduct- ive state. The vegetative apex during the period of maximal area was broad and flat. At the time of minimal area, after the appear- ance of a leaf primordia, the curvature was greatest and still very low. The leaf primordium grew more rapidly than the stem apex which was never "overtopped" as long as the stem remained vegetative. His photomicrographs illustrated stem apexes arranged in a pattern described as typically dicotyledonous. The tunica was two cell lay- ers deep and regular; the apex was filled with a lens shaped mass of meristematic tissue in layers parallel with the tunica. Cell div- isions in this area were radial to the arch of the apex. Philipson recognized the onset of flowering immediately by the more strongly arched apex which "overtOpped" the primordium of the highest leaf. The morphological appearance of the flower primordium suggested that the primary change which led to the onset of flowering was an elong- ation of the cells immediately below the apical meristem. This cell elongation was suggested to be the result of: an increase in osmot- ic pressure, an increase in the plasticity of cell walls, or a de- crease in the permeability of membranes. Since the increase in size was along one axis, Philipson concluded that the factor involved was plasticity of the cell wall and cited a report by want that auxin had an effect on the plasticity of cell walls. Popham.arfl.Chan (1950), described the vegetative shoots of cer- tain.varieties of Chrysanthemum morifolium by dividing them into five distinct zones (See diagram POpham and Chan 1950). They desig- nated zone one as the overlying mantle of regularly formed cells, two to five layers deep, covering the apex of the shoot. Below the center of this mantle, or tunica, was located the area which they called zone two. This zone was recognized by its cone shaped arrange- ment; being three to six cells tall in the center, one or two cells thick at the top, and five to eight cells in diameter at the base. Zone three was represented by a cup shaped area of cells, situated below zone two and extending upward to the periphery of the apex cutting across part or all of the layers of the tunica. The larger cells, below zone three and in the central portion of the stem apex, were designated as zone four. The cells which comprise zone five were situated peripheral to zone four, not so definitely arranged in longitudinal rows, and were observed to be much smaller. Arbor (1933) reported that the differences between the flower and ve etative shoot in many plants are recognized by: A change Lt at. in the leaf type, a chanee in the relationship of the lea'rs to U a .v the shoot apex, and a telescoping of the floral axis. Sharnan, while studying he develOpmental morphology of the shoot - .. , w .1.v . , - x . apex of Agronvron lepens, observed that t e chan.e over from a purely I.) vegetgtive to the reproductive st: e was extremely'rapid and he was .1. unable to photograph many intermediate stages made visible by C.) dissection technique. 5e suggested, from scidying microtoned mat- erial, that the initiation if floral parts was evidenced by peri- .1. clinal division of the dermatogen and hypodernis. EXPERDIEIHAL PROCEDURE Controlled tepperature chambers: In May 1950, 8h rooted cut- tings, variety Gold Coast, were planted two inches on the square in garden soil in each of two galvanized pans 30x18x7 inches in size, coated on the inside with asphalt paint. A Space was left unplanted at each end of the pans to insure uniform illumination of the plants when placed in the refrigerators. One pan was placed in a green- house with an average night temperature of 50°F., and the other in a greenhouse with an average night temperature of 60°F. Since Kip- linger and Hasek (1939), reported that temperatures below 60°F, re- tarded flower bud initiation and Post (l9h9), maintained that flow- er buds do not form in most varieties at temperatures as low as 50°F., these two temperatures were selected for comparison. Ten days later all plants were pinched, leaving three leaves on each plant. Forty- five days from the date of planting, both pans were moved into 50°F. and 60°F. refrigerators reapectively. These refrigerators were 3?6 cubic feet in size and were equipped with thermostatically con- trolled temperature units. Each pan of plants was lighted with eight to watt fluorescent and four 300 watt incandescent lights, giving a total illumination of 1000 foot candles at the tip of the plants, (Fig. l). A constantly flowing water bath was hung directly below the incandescent lights to minimize the temperature differential between the light and dark periods. CA) Seven days after the plants were moved to the refrigerator, the light period was reduced from 16 to 10 hours per day’and col- lections of the stem tips were begun. At this time those plants he 50°F. refrigerator aVeraged 8h mm. in height. The plants .J S d— in the 60°F. refrigerator averaged 108 mm. in height. Collections were made of the stem apexes, 3 from each tamper- ature, every 3 da;s for 36 days. These apexes were then killed in chron-acetic acid and embedded in paraffin, employing he technique described in Johansen's "Plant Hicrotechnique". Serial sections were out 12 microns in thickness, with a rotary microtome, stained with Haidenhain's haematoxylin and safranin, then mounted in balsam for examination of the develOping apical meristems. All the stem apexes were removed and hand sectioned after the last collection was made. In the hand sectioning and examining tech- nique, tweezers, a razor, and low p wer binoculars were used. The stem apex was stripped of its larger leaves, placed horizontally on a firm surface and held steady with the tweezers waile a median longitudinal cut was made with a sharp razor blade. The cut surf- aces were then examined under 30X wide field magnification to de- termine the presence of floral.parts. First greenhouse crop: On September 10,1950, sixty uniform, rooted cuttings of the following three varieties: Gold Coast, Mary L. Hall, and Sea Gull were planted in a homogeneous soil mixture, using a raised bench in one house of the range of the Plant Science Greenhouses at Michigan State College in East Lansi g. A replicat— ion was n1 ted in a grouni brnch in another house. The night temp- on . eratures of these two houses were SOOF. and 60 r. respectively and the plants were treated mi i1 r1 to thee grown by commercial grow- er in the same region. The plants were Spaced six inches apart U) in each direction and the teps cut off 19 da;s later, removing all but 3 leaves and l shoot from each plant. A system of lights consist- ing of 100 watt lamps, h feet apart, hung 3 feet above the tips of the plants 5 used from the time of planting until November 2Cth eriod with one hour of 15 ght each (‘2‘; (77 deys) to iIterrupt the dark * night at midnight and keep the giants in a vegetative condition. Six stem apexes of ecch variety from both the EOGF. and 600F. night temperatures were Collected for studies of flower bud initiation every second day through December 5th. Second greenhouse crgp: A replication of the temlerature ex- periment under greenhouse conditi ns was started on the 7th of Jan- uary 1951. The same number of cuttings, taken from the plants used in the first experiment, were rooted, planted and grown as previous- ly using the same controlled temperatures and daylength. Because phase of the experiment was conducted during the wint- L. much of this er months, more scour te temperature control in the greenhouse was possible. The daylength was increased by a system of lights, simil- ar to thrt used in the firs crep, to keep the plants in a vegetat- ive condition until April 2nd (85 dags ). At this time black sateen shade cloth was Lsed to hold the da41en3th below the critical period and continued until the development of flower buds was evident to the naked eye. The tips of the plants were removed February 6th to induce branching and all the resulting shoots xe.e allowed to develop to maturity. Collection of the shoot apexes was segin on April hth and continued dai1;, until April 19th at which time e?- aniration by the previously described dissection technique snowed * v flower buds evident in all varieties from both temperatures. FIG. TT p-d Fig. II. Diagram of Chrysanthemum leaf with Jark arefig to ShOW location of areas rcnnved to exawine tFicknoss, number and size of chloroplsrtq (gctugl size). ... as. I) \L) fin rr mm LJTJ -J 21.3 I ,L, A , A..-” m"; w)‘ 10‘] '--) .-_ ‘. -H‘ 0. I“.V JS ‘ ° . 1" ,‘r‘ .!.1-.2, 1 _. ,. .--1 ° .. 1- -. ,.,_..L m1 Comficr1501 oi léii Jilucr:so r,u Size of C lore l »L3: L13 A ‘ A p‘wu- w “r "" I ‘ I- " " 1". "' 1‘ :\ Q 1’ , ~‘1: . ‘- \ ‘ "‘ u -v _L,_J I. .S ‘1‘ Q ‘Ylt {1 t C. A11 w-fl (Inf. f)? ‘.:‘_'.F‘ (’1‘ f :"I;~._.u?'l f, .' "7.1.- ‘1"; “‘1‘!- J. J. U - U 0. . ' 11- , -- .4” - -Lw. .7 4.1-. - fl--- - ._ . .1. A- L. - 3.;J h xi.e l..r t :Twsr:ru ~n l, fit/=1 \,«~Pn nu. _[. J*1 9 pr,; f'L,1‘~ V . ’ '0 '1 m ' x Q 'L‘A . 'L Lucfia VA,‘ ‘a-‘p wal~-—A-- ten QC: TOG» U 101‘. 1.0 COIIL'JJ‘B u. 0.17.“ Sbl~§1Cuu1 .4, 3:12.an .t. LUg‘. ur; U v- A114. 1- r‘ n “\ ‘.y’ . r—-~ .nr‘ ,- ~--, ».\ “er” CUJ. ' [C ‘1‘1 *rO'l 1, 1 1-17:3.“ 100:. 44-77-“) 9-,. I 'L'nr‘ A t . , - a , ,,.:J-a .,. .. A. 1.. 'v o (7-1: . OL-LLPUH la?" a, mid tron ; $1.:l1r ,.i.lnn, 93 u on 40 l \,Lu. "r-r\ -- ....,-., :. “d .: . ° v L ,.. , . .. 'i .. r' 4x.-.- 1,—~ . ”3 : - 4-4., .51“? C-r;_.‘”.l-l-. T’LLCI‘CE villi", $1.1;- LJO A ;e_.SL13F_-‘. _-.~’3-.l. u. ‘ 1.81311: 33 ( :4; Cl? .9 o O 0;. cfilorvjlagts i ‘ f 1 l?1v¢s taPcn from pl nus i M - ..L. , m1. , LL: 1.. ‘ r. - - n. . n‘ A -.~ to‘rcrguarws. ra- lpd' ”liclneas ngLJJ ifnfi LJC tO g70 microns ,.-,1 .-. H - in _w. . -‘ w, .9- ., ‘ ...,:1 .n .. l .1. '7 r’ V..!,., _ L‘. .,.., v.4»: 7‘. ....']_Z'5 O... C;11.C)l‘()iw_._...'o$ J.-l;uz.‘t.a. .3301 \2‘00 L10 to) 1‘..LK.’I'(_".JA£> c-]_0-ii_, ’fl —. u;- _-. - “1"- ; r‘ 4 .‘ ‘ ‘ 1—" . n V' 4'1 ' ~— r4- m . t e_r lenur,u clirotur on all lelvcs iron bOufl tenjcruuures. lhlS F: _ o 0 _ > o _o 0 V“ __ ‘ A _ the nuclei indicate tLet a1ticlinul dIVlSanS are host freqaent. Immediately b 10:: the tunfi co. a mess of po vhedrel cells, epfroximat- ely ten cells deep and fifteen cells in.uidth, is evident (B). This herecterized by: irregular cell errgn3e- $3 3 3 H O Q 3 C) H 2 ,5. O J i“ 0) O ment, much pericl' £1 and inticlin: l 0: ll divi “1 n, enclc ;'toplem exhibiting a hi3hly meristemutic condition. The brect primordia (C) are characterized by their hirhlv meristonetic cells. At the left ” the figure they extend farther down the cylinder thaan t the ri3ht l where the cut is non-median. Below the grouping at the tip of the to the bract "3 bracts, he cells are regularly elongate. Exterio primordie is found tissue of developin3 leaves (Figs. III and VII, D). At the left of the figure are shown perts of two segerete lesves or nt FICt (P DJ CD *1 l._}. ti ,J d l._]. C’) H. ncrts of taro lobes of the sure leef. The leaf on }.J \3.) and a row of elongated cells four to six cells in width, is cont- inuous through the center of the leaf. In places, these procamb- ium cells are developing into protophloem and protoxylem, the be- ginning of vascular tissues. Transitional stage: Figs. IV and VIII are illustrations of a longitudinal section through the shoot apex eighteen days after'the short days were begun. The apex is larger and more highly arched or mushroom-like in shape. The two-cell layered tunica (A), extend- ing over the arched apical meristem is present as in the earlier stage. The corpus is larger but similar in structure to that ill- ustrated in the early vegetative bud. The increased meristematic activity in this corpus region suggests that it is in the earliest stages of floral initiation. A group of longitudinal cells is pres- ent in each of the two large bracts (C) which enclose the develop- ing flower head. The tissue in each of the arbitrary regions is sinilar in nature to that found in Figs. III and VII and at the right of the apex a young bract primordium is comparable to those found in the apex eighteen days earlier. Ybung_reproductive tip: Figs. V and IX show the stage collect- ed twenty-seven days after short days were begun. It has been chosen as a criterion for identification of a flower head in the establish- ed dissection technique. No floral parts are recognizable. The apex has a flattened appearance and experimental observation has shown that flowers develop from this structure. It is at a stage sufficiently large to be recognized and distinguished from a vege- tative bud and consequently serves to establish the initiation at an early stage of flower deve10pment. The tunica (A) through num- erous anticlinal divisions has expanded along with the inner tiss— ue and.continues to cover the enlarged corpus (B). Many periclinal and.anticlinal divisions of the cells in the corpus have resulted in the tightly packed and mushroomed—like appearance of the apex. The cytOplasm is more dense and fills a larger prOportion of the cell than previously. Five bracts envelOp the apex in contrast to the two shown in Figs. IV and VIII. It is apparent, that as the bracts mature, the cells become larger, more vacuolate, and inter- cellular Spaces develop. Further develOped reproductive tip; At least eight over-lap- ping bracts, enclosing numerous floral primordia, are shown in Figs. VI and X. The tissues cannot be as easily divided into the corpus ani tunica areas in this stage of deveIOpment although the tunica cells still appear on the periphery of the individual primordia. Figure XI, an enlargement of an early stage of deve10pment of some of these primordia, indicates that the early initiation of floral parts is evidenced by localized rapid cell division resulting in protruding masses of cells. Unicellular chains of globose cells l0 l0 arise between these protrusions. A later stage in the develOpnent showing three individual primordia as well as the inter-primordial structures is illustrated in Fig. XII. The tip of the flower prim- ordia at the left of this photograph is cupped, in contrast to the other two, indicating that the form of the flower at this stage is not uniformly cylindrical. Numerous serial sections would be nec- essary to make an accurate morphological determination of the indiv- idual flower develOpment. The unicellular chains of cells that are evident between the flower primordia apparently deveIOp into the pointed hairlike, multicellular structures (chaff of the receptacle) found between the florets of the mature flower head. Pistils may be seen forming in the flowers where differentiation is most advanr ced. These are located on the lower regions of the periphery of the flower head (Fig. X). Meristematic activity in the apex of the flower head is concentrated mainly in the developing flowers. «J. '1 .L-_-.,:..- - -- 1-1 -. 1M: -, --°.:--_.I. , - Controlled u,'AC:aulsc trap: clonsr ‘!s or; iniuiaoei in A .. l. J. .0 1 1 A,“ 1.1 ., 1 ° .L1_ ' -fl ' ... .-..1. 1., J. - y; pe:Cent Cl o1? StLhS on cue plants in unis exporiaent A” u were - ..J- - 11 . .°-.1..:. ,1.-- ,_ , , 1- '1 . , 41.1 ,.-I- K (711 eronr no 60 1. ice night tauperatire was mth constantly at v0 I. ‘ 1- .1. _ , 1...- 1 , _ 4.1- . 1-1 0 ,1_‘.L __‘ 0 .. _ r F) '1-1 .. _1 fad tie t“;~rrntu:o curia UL? ~;Vl.3ho '“led rose to 100;. de 1-,“ . - -, “,4.” 4. __ , 1i, .. “.1. . 4. . v - 14 “1““. hell varv co ttnnulu. Chip 1 percent of the stabs on tie gutnts 1° «fl-q h‘r\-Ay\-.-r1-—. '- J-1-.-L .,-.., fl, _, ,4. r’nO-H :n:.'.,-,J_ ,_ nl‘ - M. . ~fl~ _-ll 1;;'. a_~_‘ lulu b. the mu C} U; 0 7T". 1,‘ u (it. I . .LLLJ '«~.1-;,l.'r'A _L 0: t4. LNcLL. 1x. “I ' .1. 0'11 1 J. ' n '7 1 duds on pianrs grown at (O r. becare ronroeuctive a4tcr 2; score A 1. n“ -4 - uAr. J- ‘q- , ,a:- r- a f.-. . o‘ v. .Q,’-11-' N -\- < ° QCCOBHlUs U0 the wrbttrofD stage described preVlOuow§ under 0 .1. f -_ .. ~ A.” 4. °.,-. N. ° ..,.. ,. -l .g. :,-- , .1 .x. ”deun3 repc.Jico (e tl‘" and illustrated in Figs. V and I1. is 1 ,1. . ‘ ‘. 'L ‘2 ‘fi v 9 " ‘ \ O “l- ‘L . “ ’2 . . 3 r " " tJ,S time there here do mums in a r;prouu olVC condition in lny ¢ '1 1 ~'- v w 1‘ “ ’- - 1 n W L ““ «o .- J" - O“ ‘m‘ ? ‘a . vv Scnples of ste.s from tnt ‘_ants 3rtun at p0~u. Alter J6 snort dips ~ he plants were hand sectioned, there was onlv J. 1 I one plant in each treatment that was not in one same condition as he others in the sane treatment. I-Iumb er of fimrtdafl \I .- ln \O'QU‘LW \l \I 7“?“ 4—“ \,=J O\U'l \1 10 11 *First Collection Uov.27,1950 ** First Collection April h,l951 m .L, a fi? fi ...-‘JJ.'_J I Gold Coast 500 600 00000 00000 XOOCO XXXXO XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX 000 000 000 000 0000 00000 000000 000000 X00000 XXOOOO XXXXXX FL 12R BUD IEII'PL‘LTION First Greenhouse crop Mary L.Yall SO0 600 00000 XXOOO XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXX‘I XXX XX Second Greenhouse Experiment 000 000 000 000 0000 00000 000000 X00030 XX0000 XXXXDO XXXXX 000 000 000 000 0000 00000 000000 000000 000000 XXOOOO XXXXXX 000 0000 00000 000000 X10000 XXXXXO XXXXXX XXXXXX Sea Gull 500 600 XXDOO XXOOO 00000 XXXDO XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX 000 000 000 000 CCO 000 000 000 COFQ X000 00000 XXOOO XXOOOO XXXXXX XXXDOO XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX O - vegetative bud x - flower bud 5-4- (\3 U1 First greenhouse croQ} USi C the hand sectioning di ection technique des rihed previousl; md thu fl ov?r bud criterion (Figs. V and IX it was hossible to record the d eta lresented in Teole I l (First Greenhouse Crop). The stem spores were removed from olents of the first greenTonse crop at two day interve ls follO'rinr shost day treatwert Cnri ; Yovenber and Decenoor of 1951. Flower heads in the earl" bud stage were gresent in tro of the three varieties after one short (C' in t}_e 600 F. tenwerltrre Flower buds had been -v foull in all of+ ,.o v-rietivs from 10th tengeretnres after three dx“s and t" live or nor: de;s none of the sang es taken were in C vegetztlve con ilion. In order to suyplenent these resul :pexes were collected from the secord gre FOlCe C10? in April of 1951. Second ;rern we se CTQE} These calleotions were made at dai J intervals “sing the 5 re tocfirigts fl: cx'riretinn Lrt loo {1?ic t- lon of flower re 4.. In gCneral, u|over initigtion was nrt es r'n- id in this or3n. Tfie first occurrence of flover initials in stem ageXCs was in tfie sen les of Sea Gull fr on the 600F. P3Use 6"&NF ned . 1 m‘ ‘ L g-ivr —- RI. ‘fi [‘U'I ‘ ’1 " \-~II~1 - . -~‘ (‘f‘ five days alter snort dgys were begin (T elle I, scoono Greenhouse m‘ \A . n--. r. ‘3 r“? 1L _,,...-, ._;- 1:, no ’3 .~ a" h; _V . Crop). .l; 9:1nu, o cellll.ae vs; lid (J.Ll;' Civnuse, 08¢ Chlj (-15'Mb -I ‘ L1 - .. ‘1'- q,‘ . *‘fi fi -- ..r-‘-,-‘ r M~~ 'n iju n nwro r r1d in its lCSQonse ulun bOll :Oouu or ”a.” L. Iellc l-ll v: ri flying did drod on flower buds one or two days earlier 0 ' £— . _ z - e 4 ML rm ,J.. .- . A. . in the 50°F. than in the 50 F. te;jersoure. lie 1 seat occurrence of flower initials in stem apexes was in the sannles of Mary L. Hall from the SOOF. house ten days after short days were bug-gun. It required eleven short days for samples from all varieties at both temperatures to form flower buds. TABLE II AVERAGE HEIGHT OF PLANTS IN CENT JETTRS (168 Plants) ' 1 H 500?. 5 600p. y-___ .._.____ .__._.__ ._._ _ _._-._. __._.V-_-_______. 1 S __ _m¢___._‘.._. _,________-, .- .... - -. . ._.. .. o - _ -n At time plants were if i placed in control- ll .3 4- C m" H ,. f . 1'3kt De: L‘; (,‘J. ;.tlkareu. I. 61.); 79.6 Seven long days 1 _ n4. . 1-1v91 o }- 8)}.00 ‘ 10807 After 36 short -\ ‘ days. 5 109. ‘ 123.h Gold Coast 500 OZ. in. OZ. 1.00 18 1.50 1.00 19 1.00 1.00 19 0.75 0.75 21 1.50 1.25 21 1.25 1.00 21 0.50 2.00 26 0.75 1.00 21 2.00 1.00 23 1.50 0.75 20 0.75 0.50 18 2.00 1.25 22 1.50 1.50 2h 1.25 1.00 21 1.25 1.50 22 1.50 1.00 23 2.00 1.00 21 1.50 1.00 21 1.25 1.75 2b 1.25 2.50 26 1.50 0.75 16 1.25 0.75 21 1.00 1.25 25 1.25 1.00 22 2.00 0.75 18 1.2 28:25' 533 3.2 Averages 1.13 21.3 1.33 Ht'fiTTfi TTI _. .- 1‘37L .h—l- WEIGHT AND HEIGHT 0F PLANTS 60° First Greenhouse CrOp in. oz. 3 1.25 30 1.75 2 0.75 32 1.00 3 0.75 26 1.00 28 0.75 36 1.00 32 1.25 26 1.00 35 1.25 32 0.50 31 1.00 33 2.00 32 1.00 36 1.50 32 0.50 3b 0050 31 1.25 2 0.25 30 1.00 31 1.50 30 ---- 36 ---- 7%0’ 22.75 31.5 1.03 in. oz. 28 1.75 30 1.00 22 0.75 26 0.75 22 1.00 28 1.25 31 0.75 27 1.25 26 1.00 27 1.75 3h 1.00 20 0.75 27 1.25 30 0.50 30 0.75 26 1.25 2h 2.00 20 1.00 29 2.50 22 1.25 28 1.50 38 1.25 "‘ 0075 "“ 0075 _... O. 587' 2 . 0 26.6 1.1h Mary L. Hall 50° 600 in. 0Z0 an 1.50 39 0.50 3 1.25 33 1.50 3b 1.25 38 1.00 3“ 1.75 37 2.00 3h 1.50 MS 1.25 37 1.25 36 1.25 ho 0.75 2b 1.00 3 1.00 37 0.75 13 1.25 35 1.00 86 1.25 36 0.75 37 1.25 38 1.00 35 0.75 37 1.50 1 1.00 2 55755 36.8 1.17 50° Sea Gull in. OZ. 20 2.25 17 2.00 21 2.00 23 3.00 21 1.25 21 2.25 2h 2.00 zh 1.50 25 2.25 21 1.75 26 2.00 22 1.50 21 1.75 21 1.00 21 1.25 18 1.25 25 1.25 19 1.25 23 1.25 19 3.00 23 0.75 19 1.50 19 1.50 2h 1.25 20 1.7 537' 2. 0 2l.h 1.70 f\ the hei ht of tie plants grown in the controlled temperatures were made at 3 different tines when the' were removed from the green- house and placed in tFe controlled terjeratures under long days, at the time the short days were begun, and 35 dags laterl Then all plants wer removed and diss cted for exaznination. The average heirht of the rllCfltS in the 60°F. chann;r was approximately 2 cm. greater than the average height of those grown i. LLB SOOF. chamber at each time ne'C‘relonos were recorded (Ta le II). h average gain in he :L; ht during the 7 long days was "re; tor for pl: nts from ....,-. ~ - 1 ,..: n. " both tegplr t '0 t-an tie total aver.ue U.Ln airing the lOllOIJing 3'9 A“ .- .. - -- - -. . ~ _- ,. the oliference in »lze and gdfllty of breath of the three varieties r3 ’ “ r : Ana ‘- \\ A A Cu ‘fiA n4- .. L . grorIn at 50 azd (C F. night bewieTntuTDS. Tue data presented in A - .N It 0“.‘_ .0 hr, r. 1“ r 1 ch10 III record the telbht and heJUTt 01 23 nlnAJU Ll tie evict- Fall from each «. the same two temperatures in the firs . A ,- , '— _ . J- .- A - 7‘ r- 1 . r'! -¢ I l-J' : 1 ‘ "' f'i .“ .’\‘ “. crop. In 01:; VLTICU‘ the stem 104;tfl 1. orl'ver L“ Rind-v o’~~~ t3 nor males. The average dillerences m>¢o x. at; >42 . .Eq .5: .8“. .21. cm ow. o._ 0,» on Q on ow 0.. _ o,“ 0,. 0? pm . 0.. I. 1 3 n u U :00 W. n a n m 1 a 1 1 .1 u 2 1. 1 1 u . . ( row .12.. 1 1 .. , 1 . . . . 1 .... 1. 1 1 . 1 .1 D. 1 1. 1 1.11 . .1 .1 _ . _ . 1 . _ /\ 11 1 \ 1 1.0x. .1. 1.11 1 11 (1 <11 \ 1 1 1 .1 . 1 11 1 K 1 1 _ 1 C 1 1 1 1. .111 11 100. ,. 1 1 ,. _ 1 1 11 11. 1.. '8 ._ . , . : 1 . ,. 1 111. 1.\11 , .. _ 1 1 11. f 1 1 .8 mwmaoxzuumo moon 02¢ on 2. mucah<¢mm2u# >42 E4 .3... .uuu .21. om cu m. 0.» NW 01 0» ca 0. 1 ow 0. on - r - L5 2 I. 3 I .0 \rS\/ n \J 11%.» < .2 u . 1\/ Hobo: .00 m .1 3 . 1 m z a 3 9 U , 3 ~26... .oo .3 n u. .2 .oo oo Guanozzuutc $.00 02¢ 00 z. mucahkcumxuh 1.19.2 2(u2 '3') I «'J . m 1‘1 V—‘T‘. r11 ._1. r .- -? ‘ J- .1 v-w 4 -3 ° 1.. 4- (L1 -3 1 1,. 1 L / r1ve g frr s+oL 1or 111 v1r1rtLos 1- “wret— f’ , .1. / fr: .11,‘ 1,11 s - :n 1 ‘ , p m“ (4' C t‘un L.” g, _ rm {”1; '3- _"':" cue ‘ _- r on]: iron v V 0.53 ounces in the variet; Sea Gull o 0.1] ounces in I'Ur~r 3. Tell it can he :u.fL.oirrt to r1ise the s ers. The J7LV73 are smaller end appear more thick on at the lover tehyoroture. They are not an; thicker b; neasurement (Se Aneto nicel COIL.eri.son of Lesves) but 1105 s flal; ; ,e1r thicker al a result of the conoentrgtion of carbohydrates c;m..ing a d&?£7? green color and greater turgidity. The difference in spray format- ion (Fig. XV) as a re:ult 0f t3:‘ereture diffcrence is of interest, the longer pediccl on the plants from the 600?. te*tLr1 re making a more ettra ctiv oflower. The length of the 510 iNf period fron the time tre roct d cutt- ings vere planted in the bench until the first crop was out we: 9 da*s longer rthe Ve-riet" Gold Coast ehd 12 days longer for the [0.43 , I 3cm tev‘or'tnle U rn for the same variet- l (D Variety See Gull at t ies at tle higher ten Wmer eture (Tdble V). The : ems were out when there were at least three flowers open on ea ch stem. This stage was considered to he of good commercial quality (See Fig. XV). Both l,r~ti :13s of the variety fiery L. Fell matured at the srne time and were out after lhl da;s of growth in the benox The 3vere;e weight per inch, which is indicative of quality, ,1 ,14. . . , , .2 4.1.1 o . 4.1- - . -. rm 1 , mos greutegt for all v.r1eLst 1rcm uLC ,w r. 11:1les. Lne ever1go difference for the same variety at the SO and équ. temperatures nun-r“ 1.4 m “T L.’L§l‘ I ‘ uni Ia'ElGlfT AT’D TEIGFH‘ OF PLAYTS Second Greerflious e Crop A. ." «‘9' Gold Coast Mary L. Hall Sea Gull 500 600 500 600 500 600 oz. in. oz. in. oz. in. oz. '1. oz. in. oz. in. 0.75 18 1.25 23 0.75 27 1.00 28 1.50 33 1.25 27 0.50 16 0.50 18 1.00 26 2.25 37 2.50 30 1.75 21 0°50 18 1.00 19 1.00 2 1.50 32 2.25 28 2.00 29 1.00 17 1.00 20 1.00 2 0.50 19 2.00 27 1.00 22 0.75 19 0.75 a 0,7; 23 1.00 30 2.00 26 2.00 25 1.25 18 1.50 23 0.90 18 0.50 18 1.25 28 1.00 2 0.50 18 0.75 19 h.00 36 1.00 27 .25 28 2.25 29 0.50 15 1.00 19 1,30 23 1.2 27 2.00 28 1.75 2h 1.50 17 1.25 18 1,20 27 1.50 28 1.50 28 0.75 21 0.75 15 1.00 21 1.50 29 1.50 25 0.75 27 1.25 27 1.25 18 0.75 20 1.75 28 1.00 22 1.25 28 1.25 26 1.25 19 0.25 12 1,90 28 0.75 23 1.50 30 1.50 29 1.50 Eh 0.50 16 1.20 27 0.75 19 2.00 2h 1.25 26 0°75 16 0-25 lb 1.2; 22 1.00 2h 2.00 Zh 1.25 31 1.00 19 0.50 17 0.75 29 1.00 29 1.25 2b 1.75 3 0.50 17 0.50 13 1.00 2h 0.75 22 1.25 22 1.25 72 1.50 18 0.75 16 3,25 32 1.00 2h 1.00 18 1.00 2 3.00 25 0.50 18 1,00 21 1.00 2? 2.75 33 2.50 3: 0.75 17 0.50 13 1.75 25 2.00 31 1.00 21 1.00 26 0.50 17 1.25 19 1,:0 30 1.00 23 2.00 26 1.50 27 0.50 1h 1.25 20 2,20 21 1.00 23 1.75 30 1.25 2 1.25 17 0.50 15 1.00 27 .25 27 2.50 27 1.95 26 1.25 19 0.25 18 1.25 29 1.25 28 1.75 21 0.50 21 2.00 21 1.00 20 1,50 28 2.75 3; 1.50 2b 1.50 29 1.25 22 1.50 22 1.25 27 1.50 2.00 26 2.00 27 1.00 18 0,50 15 2,00 27 1.00 22 2.00 27 1.50 2 1.75 20 0.50 18 1,00 26 1.00 25 1.75 25 1.00 25 1.00 17 0.50 13 1.50 2. 0.75 17 1.00 18 3.25 35 1.00 17 0.50 12 1,25 19 1.00 28 3.00 31 1.50 30 2.00 21 0.25 13 1.25 28 1.25 27 2.00 21 1.75 25 0.75 111 0.50 11 1.30 25 1.75 27 1.50 26 1.25 2 2,00 26 0,75 16 2.50 3h 2.00 28 1.50 27 1.25 27 1.25 20 0.50 12 ' 1.00 19 1.00 2h 2.25 26 0.50 25 1.00 23 0.75 15 1.50 2 1.00 23 1.75 23 1.75 31 1.00 16 0.75' 17 1.25 21 1.5 26 0.75 22 0.75 25 0,50 15 0,50 17 0.75 19 1.00 25 1,50 28 1.50 29 1.25 23 0.50 12. 1.25 30 1.00 2 1,25 25 1.25 22 0.50 16 0.50 in; 0.75 26 '1.00 18 1,00 21 1,00 28 1.00 20 0.50 .3 1.50 26 1.00 23 1,50 2? 2.00 31 1.25 20 0.50 ;y;_ J 25 29 1.00 26 1,00 _§§, 2.00 .43; .hh.50 739 29.25 660 56.00 10h5 h5.70 1178 66.50 1019 59.00 1121 Averages 1.11 18.5 0.73 16.5 l.bo 26.1 1.1h 29,b 1.66 25.5 1.88 28.1 k) U1 was 0.0] ounces heavier in all varieties. The average established by the Corneid Standard Height (CS?) System (P05 19%?) .nd with the exception of the Variet; fiery L Hall where the quality also appeared better, the grade was ingroved by growin in the 60°F. temperature. From grades of individual stems it was found th;t ever 50 percent of the flowers in each variety were ad- ’rovn at 60 rather than at 50°F. vanced at least one grade by beinm night terperature. Weight and height of nee-nd crow of cut flowers: All of the stems of the variety Gold Coast in the second greenhouse crop were abnormally short (Table IV) either as a result of poor nutrition 7 or from Chrysanthenum stunt. itile the average height of stems was two inches greater in the 90 than in the 60°F. night temperature, the poor growth of these plants does not warrart much consideration being eiven to this difference. U TY As in the first crOp, the varieties fiery L. mall 2rd Sea Gul‘ produced longer stews when grown at the hiQher temperature. The averzge stem length was only 3 inches greater for both varieties in contrast to the 7 inch ave age difference in the first crop. In the second crOp as in the previous crop the average weight ,hose from the 50 than from the 600?. en- vironm nt. The difference ranges from 0.18 ounces in the variety Sea Gull to 0.26 onrces ii the variety Mary'L. Fall, omitting the r I J'J xx . .4. 4‘1- ] n f (‘4' m“ "i . ”n5 . :1: va11,u; Colo UOdeU. lhla dlii.rc ce is ‘ r' (-1 .‘ (‘ -.- ‘QA -: . ~ 1 . f ‘ : .fl ‘ -.. - not co rre-t as lr,'\r.Lou..:-l; ano 18 not con;. ste21t for v01i1t_es but ‘ O- . ' ‘ --\ ~\ ' S . n r.. ': -. Q a 1— ~‘ r‘J' .“ “1.“ , . the Wei Lt cl stem is athn Liegtur at the lover te_uerature in ' -er coth crows. ?b 11 varieties required a Lre:ter number of days to produce mature flowers under the low winter light intensities duri.u3 he second then during the first greenhouse crop. This difference varied free 17 to 25 d:;s at the low tenpcrature cwnjared to from Qto 22 davs at the lij’ te~mer tUre (Table V). There we are ter $ H I unirorric;r in cutLin" tine in t1e seconl (:ro‘. All three veri e ies were rcadr to cut Jter 7-0 da"s in the 600F. greenhouse while those _’ U . C.“ Q 0 in the 50 r. greenhouse required from 7 to 16 aldatio 1131 da 8 to AS in the previous crow all VLrieties irf"n at t? we low sugar- tture weighed more for inch of linear growth h:n.res;ect ive s mp- lee fron t1: hiLh tLvrcrrcure The oversee difference for the 8838 U variety at the two t~nyeratures ranged from 0.01 ounces for the ver- a ieties Sea Gull and Very L. Hall to 0.02 ource Coast. The 0.01 ounce difference is in a JFGGI nt with t“;t found for the first crop 85d because gf the rocr growth in the verie Gold Coast, net too much si ni;icence is attached to the higher figure. The avsrLUe gr-de wes not sufficiently different to conclude es grevicusly, that the plarts grr at oOO F. were uniforrly b tter LL LL A , A at (A0“ n“ W L. h en trove r wn an a ,0 :. niLht teugerasure. n___.__—-__.___—-._ _ . .__ v-v—_ _. I T‘f‘wranY - J.JL‘\‘J..‘ 001d Goes o 50 First Greenhouse Crop Timber of dogs from benching to harvest, 1ft. per inch in ounces. Crede— (CS!) Average of 2S ste s. 137 0.05 First 128 0.01!» ~11"; 21.x uI‘a m T" L AR Lib V Dal- 0.011 Ertr Second Greenhouse Crop In tuber of days from benching to harvest Wt. per inch in ounces. GI‘ade- (03:) Average of [1,0 st ens . O J- rquu .L—d. 150 1'": ....L 1‘ .LI‘DL: L. 166 0.05 .153. L re. Average For Both Crops Thu 1b er of days from benching to her\est. 3R4 per imfli in ounces. Grade-(SSH) H ‘4'... C) 0.01; Dire 115.6 0.035 Eire CF CRCUIVG PEQiCD LID QUALITY OF FLCWCRS Sea Gull too 600 I. Fancy 166 0.06 15 3111!, 0.055 0.0h5 First F: ncy Tonvrnn vr r1 wr-‘rw T rho D- ' QxluLJLJTC CL' ' Q -- Juk—JJ '5 1 m A . ,. a...” 1-....-1 _- 1.1-- ., .. .L .2 .- .11 J. . 1 .2 - 1L; (EL—111-111-? 8.:‘1.,1m:.u.111. in Lula) V‘?£_,€‘u;.t.1-Vb‘ 5.11000 O.'. {318 VLI‘LDf'Jr _.- a.) ‘- biA end Chem (1350) for tto Variety Fittersw gt. Zones 1 e“fl 2, in fiLCi? description, correspond very closel; to tir tunica and u;— p;r carLUs (A and 3, Figs. III through X . It va-s Lif icult to segregate zones 3, h, and S and t5; are? viich congrfses these zones in Foyhin gnfl Chin‘s descrigtion wxs referred to in thi;3 in- va‘tigztion.ss bruit 3:1 lezf primordia (0 erd D, Ffi‘£= . III tTrguLH X). Earl; flo yer bud izit ati n r;s obs rved to be in conjunction 7 .1. O _ v ‘H_ ‘_ . 1 ~.0 H o. with a "r1s}~oonirL or stron l~ ercnou e feet in one apical LCTlit- or, similar to tin t report ed h; Fhilivson (1?“K) in.thr Bellis ner- A onnis nrd Ch;n {1?f0) in Chrgsintflcmun norifcliun. The actual change from a veget :tive o “erro‘ucrize stite in the JRrLSLntheiun appar- entl" occurs rLLiilJ 8rd few bf?" "ore “ox ' “c5 0 rim” this trun- ritiomsl stL"e, th - is sini|sr to thr Condition in she L-¢ inoie (Sha‘flgn, 19h6). Evidence of win, periclina‘ flivisions use obser- ved in the upper com‘i s region :mr eoiitel precrding I) n . ‘ 1° r . .I-_- .L L “xvi: , 01,5 w. -‘1:-n 4--“ 2101.70]? 0:105. T1115: €11.05Lfi‘.:lU_L-:.U'3‘l 1 ll'..l- 4,1,51'5 (TL'IP') l.)r'.-_-1--.—.:_;_ 0!; 1 L‘I- _ 0.. -, .1.l...,. H ° -- ',.... .h.. n ‘1 ”we “.L 'F‘»L""r C~~» Liv“) lb-WC . -Ll’lg +10 .Ll .1621"ng lx‘dn‘l.) "(2:1 9.1.01] ,1 '1 :,.,,.. 1.0,.4- “1-- 11 , . Cr‘] _;_. "' .{nf _j-Q,lJ (9-1.“ L’nlO I "- fl ‘ “ " " " nr‘ "fifi 'L\.‘|" " n I vr-. "‘ Inn .‘L 01 011.0 0 laILS as ~ell is tee bLlLLQQBS 01 15 vs; va not silenc- \ -) \L) n The ovgrill picture of influence oi ton;er;*~1‘.re ow f1*v*r bu 3 '~ .L.PL-. 1‘ - \~ ma, . ‘1 \ . r. r .V'L -. A”':-.‘1-n 4‘“ - 3-11.1111 .-.on 0311 om; be 511171 1113?? zed by c»! 3:11.210 .13": 1.19101: r11 111;, a; -‘ . - f‘ 1 ‘. .I‘ .L‘. -1... ,.... _ '__ .2 .L‘ ‘ .3 , .~,.J-. dot; 1r~n econ oi u e turee cr.xs LroLe in ufllS LiVBEtlLJUJJJ. 1he ‘ . , .- . « -_°.' .r‘ ---.' 1- J.‘ _. .1. ,3 . ,fi, 0101. olants Lrswn 1n n c~ dition 10: thCd ;31 UC'.'GT;thG dud liLbu intensity were more constret, did 5 bstqrtiste Post‘s (l;39) con- 1 .3 .. n b 1- .1 .- O ' :4. n - 1 1 -, cilsionn tdxt gt, a: bwluo'gc F. anu igtion of iloser onus u 1 ur- lifinly. It bed Lee;1.wtlu that b; using 1000 foot cg fidWQr of li:ht in contrast to 500 used by Post, the results on the forneLion of flower bUJs niLht be diffe‘2ni. ' 1 1 e greenbouse vita I L—h "a n“ vv.‘ ,‘ -- n u - ‘~ -‘ ’3 *V.\’—-.~, -‘ LIJ. Owlll {-1 Cl‘Oi» OI. WO‘N‘WOII C; I'L‘S 1111b €5-11 1;: ' ‘ . :0 U1 ‘LJo U) .5 C) 1" 1_oss uhiform tenj rztur tir c1; clifferent procedure to growing tte some glents in controll;d tempersture ch; be wr where :t subjected to vast flect1cHons from the heat of solgr {u CD ~ -... ,, ., ,.. _,_\ _- ,. .L , , 1 , .-L ,- . ._ tee second reeerouoe e1Ler1ntno. Tez eretdie LOuUTOlS uGF: nL U '1' ‘ A ( J"~'\ "I’r‘ ‘Iv "‘ ‘ ‘, ”’2 1"”1‘ veneer Jiae recoros Irere not 00391 ewe for one 1110c b1d d3 lenL tls shorter .bno the critical light oeriod ile in th: cuttinL bench. A Iter the first two weeks of growth in the bencu tze illi“in:-tion sourc was ctanged from 60 to 100 watt inc finde.an bulbs b901LUC e it was thgnclt tnEt on the lower, somewnst sheded pl ate, the intensi * of 1i ht micht h:vo been too low to prevent (L) 13111 fo mat ion. Conjlete ten er;tnre records in the form of meLn, night end tengerttures 9or the “O and 600?. ~reenho m_1se d rirg th, second rifeonh Ur e crop are wr~ anon” '1 -_ w. 1 ,1- - 1- H"? ‘T V S Mn '179 1,; P- H“ . . .1-” (1- L77"? 5‘. :3',‘ ‘-'..-'*3L'C:."1 V 1. fl “W .\...‘.,,F lr~ r-a "- -‘ v- -‘ ~ - - . do . glam.» 0-x. nu. .-_.-‘ .91 w-.- L O . . I”, 27, .‘4 16 H vw 1 P J. ,3 _ ‘ 3... . f1 0 __ _O _ ‘ flan“ L-m ‘ PCS-TOLMUI ’BuCUL-fiu :f‘"e CE‘IILi;ifi‘ a" f“ (D p I .0 n--. .. ._ 3.0 ' - _ V #7 7’ CF?" :P‘Hnwnn Mn L;dlwnw.v:riet* Cold . _ _ “"17"; lnCu PC‘O‘C. L;_-L- Q . n. . A A . - ‘-J' ~-\ ‘ Q . lTlu; uh; 11U_u uefifi d n 1- . ~uww“ on “liltfi in 70 thfi ~F‘? t~rv~vauuw‘ ‘ - .1. “-9 _-, ,.°..,,J--- ...‘ ;JW;UCPwJ3Ll CLHfilTA__U(Jj 1.. 3 , -J— .3. " -- A .L1 1;L.uyu.gkjmeuc;d mNT 1 '1 ”J. -1 _. u- r C 1(D'.C"\.‘.. ._ (1a). ‘7. 1“ L 71".” "n."- ”v: . 4 U . _,. H, H.», \- _\_~ / ‘g‘ .1 n ’--1 .: 5.4. .l- _.‘-. --.. 1.-., .. , I 7 . I: -WI’1§31 . Kiplingor, D. C. and H;sok, R. l9}!9. S-rlrL Flouer'ng Chr Ms 1the- runs. Proc. Amer. Soc. Link, C. Preliminary 1936. port 0 SC j- . 53:T5374E39. in Relation to HOtooorwoafic REEponse. Studies on Flower Bud Differentiation Proc. Amer. Soc. Hort. T371. 0 621‘623 Q and iotmore, R. I—L of Phlox drwlmmoxldji. '-..-SCI1, 21'. R. Ann. of Bot. 10: 2 97-27‘. 19u6. l9h6. S undies S in Davelcr 3'13th 3:. F, S JO‘LII‘ Q on Devolgpwental an 33: 1‘90 fiJnea‘. 7‘ .1 1J0 U . in Develo m'ont of Irflorescence. I. Juant of Inflorescence. I; s in Develog‘mnt of Iz'florgscelloe. IV. 19L7. Studio Anm. of Bot. 285:996. 19L8. Studie Ann. of Eat. 1?: 65-72, ‘h— A... .1- 7? a (a . l 0 «.1: e... 4.1- a” -- , IOUJZJ', G. -1. 1931. "‘ Iri'e‘ “s of 9110*“ o F-T‘l-I -.<“. m“ we (‘_I':~ic;;_nt}1r>.- . __ t 5 run. PTOC. Amer. ficc. Iort. Sci. 23} 333- 392. J . . POFhE-ln: R. A. and Chan, A. P. 1930. 2013;113ng1 in th; V»; .“JH. J9tT‘Te 393V T12 of ChrgsnntFennn norifelinn:_ finer. Journ. got. 37; New; . Post, F. 1931. Peducirv tiwe DeVlength of Chrysanthonnms for the Production of Early Blooms 0v Use of Fleck Sateen Cloth. Froc. Amer. Soc. Hort. Sci. 28: 3t2-jUC. 193?. Relationshin of Te oer;ture to Flower Fud Form tirn w A . A O k 1n Cha~i§3nthenune. Proc. I.ner. See. I: ort. Sc 1. 3?: jLS'fI7. l9h2. Effects of DeLlength enfi Terporature on Growth and Flowering of Some? iite Crone. New York Agr. Exp. Sta. 9’11. 17787 0 ' o l9u3. The Effect of an Interval of Iong¥ans in Short De" Tre: tnent on tie Flowering of Chrysanthemums. Proc. Amer. l9h9. Florist Cron Proflrc tion and Forkcting. Orange M Jucd. I ”BIT IOI‘IC. Sherman, B. C. 9}”:6 The Biologz».and Develonmenta lI IOTphOlO”" of the Shoot Apex in the Gremineae. New Phyt. 4E5} 214:L. Tinck°r, M; H. 192». The ggfect of Length of Day Loon tle Growth and Reproduction ofTSome Economic Plalts. Ann. of Dot. ?9: at n '7r‘l I (.1-§’)L1'.. . ' .l: ’I‘!‘ m L V. .n... s R E w N U E T A“ 1 ummgmm