In order to examine the effect of nonunifomity of seedling number per hill on the growth, yield and yield components, seven kinds of rice populations were set; A)uniform populations which consist of the hills of the same number of seedlings, 1. all one seedling hills (1-1), 2.all three seedlings hills (3-3), 3. all six seedlings hills (6-6), B) nonuniform populations which consist of the hills of the different number of seedlings, 4. one and three seedlings hills alternately (1-3), 5. three and six seedlings hills alternately (3-6), 6. one and six seedlings hills alternately (1-6), 7. one, three and six seedlings hills alternately (l-3-6). The results of the study were as follows. 1. Differences in tiller number and top fresh and dry weight were observed among treated populations at the beginning of growing period, however, ultimately significant differences could not be observed. 2. In nonuniform population, each hill showed interaction and mutual compensation among one another. For an example, in the nonuniform population, 1-6, six seedlings hill depressed the growth of one seedling hill and reversely one seedling hill promoted the growth of six seedlings hill, compared to those in uniform one or six seedlings population, 1-1, or 6-6. These mutual effect was almost equal, so the growth of the nonuniform population, 1-6, as a whole, was almost same as the average of the growth of two uniform populations, 1-1 and 6-6. Accordingly the growth decrease caused by nonuniformity could not be observed over the growing period. 3. The growth variabilities among each hill in the nonuniform populations remained to.be greater than those in the uniforrn populations over the growing period. 4. These tendencies found in growth refLected to yield, so, yield decrease by nonuniformity could not be observed.

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When shoots of mulberry tree were pruned at the middle part of stem during a growing season, new leaves unfold from lateral buds on a remained shoot to start the regeneration growth. This paper deals with the photosynthetic rate of new leaves unfolded from lateral buds and old ones remained on a shoot when shoots were pruned at different height of stems. Results are summarized as follows. 1) After pruning, the photosynthetic rate of old leaves once rose compared with ones at the same leaf order of unpruned plant. The rising of photosynthetic rate was most remarkable in leaves remained near the pruned part of shoot. Also, the photosynthetic rate of old leaves rose more rapidly to high level when shoots were pruned at the base. While, the photosynthetic rate once rising after pruning gradually fell down and reached the level of unpruned plants during 30 days. 2) The photosynthetic rate of new leaves was different in accordance with the time of bud sprouting, that is, it was relativeIy low when a shoot was pruned at the base, because the time of bud sprouting was delayed. 3) Total nitrogen contents and areal weight of old leaves of pruned plant were higher than those of unpruned one.

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Downton et al. have recently reported that differences of photosynthetic rate among species in higher plants have close relations wlith the differences of compensation point of carbon dioxide dnd the presence of chloroplasts in bundle sheath cells (BSC). The authors made further physiological and morphological investigations on the Gramineae, and the following were obtained : 1. As reported by Downton et al., it was ascertained by us that the low CO₂ compensation point and the presence of chlorplasts in BSC were closely related to the high photosynthetic rate without any exception in about the 60 species tested. 2. It was found out that the distance between two adjacent vascular bundles(D_a), and that between two adjacent bundle sheathes (D_b) were c1ose1y related to the photosynthetic rate. Species with smaller values in D_a and D_b had high photosynthetic rate, and vise versa. 3. Differences of photosjnthetic rate which were classifted by the above four properties coincided almost completely at subfamily level with the Gramineae systematics proposed by Tateoka. 4. It should be noted that there were some exceptions in the subfamily Panicoideae. At species level Panicum bisulcatum and Panicum lindheimeri were exceptions, at genus level the genus Sacciopis was an exception, and at tribe level the tribe Isachneae was an exception. Panicum bisulcatum, without BSC and with high carbon dioxide compensation point and having comparatively large values in D_a and D_b, showed low photosynthetic rate. 5. Judging from the phylogenetic schemes of the Gramineae proposed by Tateoka, and those by Stebbins, it can be considered that the members of the high photosynthesis subfamily have supposedly evolved from the low photosynthesis one.

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As already reported in the previous publications, it was found that protein content of lowland brown rice was increased by nitrogen top dressing after heading stage or upland culture. When cultivated broadly by those cultural conditions, it is supposed that Japanese lowland brown rice shows higher protein level. In order to know protein level of lowland non-glutinous brown rice produced recently at farmers field, 250 samples (grade No.1: 42 samples, grade No.2: 45 samples, grade No.3: 46 samples, grade No.4: 46 sarnples, grade No.5 : 44samples and off-grade 1st class: 27 samples) in 1968 and 97 samples (grade No.3) in 1969 were collected from all over the country and investigated. Among the samples of the same grade, the difference between minimum and maxium values was 33-54 per cent. The average protein contents on dry weight basis of grade No.1-No.5 and off-grade 1st class in 1968, and grade No.3 in 1969 were 8.57, 8.64, 8.64, 9.03, 9.0l and 9.50%, and 8.64%, respectively. The above results indicate that recent lowland nonglutinous brown rice is not higher protein level.

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Effect of gibberellic acid (GA₃) on the growth and organ formation in rice callus tissues of the dwarf varieties (Tan ginbozu, Sankei-10, Kotake tamanishiki, Murasaki daikoku, Waisei shinriki) and normal varieties (Ginbozu, Te-Tep, Norin-8) was studied using the modified Linsmaier and Skoog's medium, contajLning yeast extract with l0-⁵ or l0-⁷ M of 2, 4-D. The following results were obtained. (1) The callus growth of Tan ginbozu, which is a natural dwarf mutant of Ginbozu, was promoted by GA₃ only in the medium with l0-⁷ M of 2, 4-D. However in the other two dwarf varieties, Sankei-1O and Waisei shinriki, the growth was promoted in the both medium with l0-⁵ M and l0-⁷ M of 2, 4-D. On the contrary, GA₃ did not represent any promoting effect on the growth of Murasaki daikoku and all of the normal varieties used, rather affecting inhibitively.These data indicate the presence of varietal differences in GA₃ response and of GA₃-2, 4D interaction among eight varieties. (2) 0rganogenesis was observed in callus tissues of eight varieties on the medium with l0-⁷ M of 2, 4-D. Shoot formation was mostly prevented by 5×10-⁷ M of GA₃, and by 5×10-⁵M completely. Higer concentrations of GA₃ than those necessary for the inhibition of shoot were required to inhibit the root formation. (3) When subcultured in the medium with l0-⁵ M of 2, 4-I) for 14 passages and more, the growth of Tan ginbozu was vigorous rather than that of Te-Tep. The promotive effect of GA₃ on the growth of Tan ginbozu, which had been indicated at 3th-4th passage, disappeared entirely in long term culture beyond the 14th passage. The organ formation in cultures at 15th-16th passage reduced about 30 per cent in Te-Tep and disappeared in Tan ginbozu. (4) The inhibitive effect of GA₃ on the organ formation appeared with the concomitant to the inhibition of callus growth in Te-Tep and to the promotion of the growth in Tan ginbozu. Accordingly, the inhibitive effect of GA₃ on organ formation, observed similarly in both dwarf and normal varieties, seems to depend on the different activities from the GA₃ effect concerning to callus growth.

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イネの幼苗の生育テストによると, チシマザザ, イネ,マダケ, エノコログサなどのイネ科植物の未熟種子においては, ぺーバークロマトグラムのRf0.7～0.8の所にアブサイシン酸活性を示す物質が認められた. これらの植物の中でチシマザサの未熟種子においてアブサイシン酸活性が最も高いことが観察された. さらに, このチシマザサの活性物質を活性炭を用いたカラムクロマトグラフィーおよび薄層クロマトグラフィーで精製し, ガスクロマトグラフィーにより, (+)-アブサイシン酸と同定することができた. また, このアブサイシン酸は薄層プレート上で5%硫酸と加熱すると紫外線下で青緑色の螢光を発することを利用して, チシマザサ, イネ, マダケ, エノコログサなどの活性物質を調査してみると, 上記4種の植物に共通して, (±)-アブサイシン酸と全く同様の所に青緑色の螢光が認められた. これらの結果からイネ, マダケ, エノコログサなどにおいてもアブサイシン酸が存在するものと推定される.

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Dead plants in alfalfa swards were examined from data of agrontomic characters such as plant height, dry weight per plant and stem numbers per plant at each harvest for three years, by selecting l00 plants at random and respectively from two alfalfa swards (625 plants/m² and 169 plants/m²) of different densities as stated in the previous report. Results obtained are as follows: 1. Most of the dead plants in the swards showed values less than the mean value of totalplants in plant height, stem unmbers and dry weight per plant at the previous harvest. Especially, in dry weight per plant, many dead plants indicated the values which were close to the minimum value. 2. Among the dead plants, about 70 per cent in 625 plants/m²-sward and 80 per cent in 169 plants/m²-sward had smaller values than x^^--s value (mean value rninus standard deviation after logarithm transformation of measured value) at least at the last harvest prior to recognition of death. The dead plants were classified into the following four types according to their growing process until the last harvest prior to death. Type I : Dead plants having greater values than x^^--s one at each harvest until a certain harvest time and also only one smaller value than x^^--s one at the last harvest prior to death. Type II : Dead plants having greater values than x^^--s one at each harvest until a certain harvest time andt smaller values than x^^--s one at several harvest times prior to death. Type III : Dead plants having smaller values than x^^--s one at eacLh harvest prior to death from the first harvest in the seeding year. Type IV : Dead plants having greater values than x^^--s one at each harvest prior to death.

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This is an histochemical study of fat and aleurone grains in rice kernel during ripening Processes. The results obtained are summarized as follows: 1) It was observed that the aleurone layer and embryo was rich in fat by staining with Sudan black B and Sudan III. Epidermis of nucellus also showed black coloration with Sudan black B as its cell wall thickened. 2) Fat accumulation in aleurone layer began at the 7th day, and was completed at the 15th day after flowering respectively. 3) Aleurone gsains were clearly observed by ether treatment for removal of fat in cross section of rice kernel. 4) Aleurone grain of rice kernel was a globle, about 2μin diameter and simpld with no structure in it. 5) This aleurone grain was stained by fuchsin basic and carmine acetate, but not by safranine, methylen blue, methyle orange, eosin, neutral red and iodine potassium iodine 6) Protein reaction of aleurone grain by ninhydrin, Millon's reagent and mercuric chloride BPB was not observed. 7) This grain is soluble in 0.1 N-HC1, but insoluble in 0, 1 N-NaOH. In view of the fact that 0, 1N-HC1 is the reagent of extraction of phytine in cereal grain, aleusone grain of rice kernel seems to be rich in phytine. 8) It was late ripening period (the 20th day after flowering) that aleurone grain was clearly noticed in aleurone layer of rice kernel.

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タバコ葉を用いて凍結法により耐凍性および浸透圧の測定を行なつた. 急冷槽で過冷却の破れたところで緩冷槽に移す方法により凍結点は安定して測定できた. 第1回凍結点は生体の耐凍性の指標と考えられ, これを凍結・融解して測定した第2回凍結点は搾汁液の浸透圧計による浸透圧にほぼ一致した. 両者の差は耐凍性の中でコロイド結合水による効果とみなした. 両凍結点とも一般には葉の成熟にともない低下の傾向を有するが, 移植前後の耐凍性の比較では移植前の苗は本圃初期のものにくらべ, けつして低くはなく, 浸透圧は低いがコロイド結合水による効果が比較的大きい傾向を示した. 土壌水分を変えた実験では低水分区で明らかに耐凍性・浸透圧とも著しく上昇した. しかし葉水分の等しい場合に換算すると浸透圧には差がなくなるのに対してコロイド結合水の効果はなお大差を示した. 一方,短期処理で摘葉の水分を変えた実験では浸透圧は葉水分の変化にともなう理論曲線によく合いコロイド結合水の効果にはあまり変化がみられなかつた. したがつて, 葉水分の変化が長期的に起つても短期的に起つても, いずれの場合も浸透圧は水分量に反比例的に変化し溶質の量はほぼ一定に保たれると考えられるのに対して, コロイド結合水の効果は短期的な葉水分変化には関係せず, 長期にわたる水分欠乏によつて著しく上昇するものであると考えられる.

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In the previous paper, it was found that the physical properties of the stalk were greatly different according to the growth stage and variety to tobacco. On the other hand, it was known that the root lodging and stalk breakage were signiftcantly increased when the weather was wet and the ground was loose. Based on those results, the present experiments were carried out to reveal the relationship between stalk strength and water content in 1964-1966 at the Hatano Tobacco Experiment Station. Five varieties grown under normal cultural practics were selected for this study. The stalks were cut at the ground level and used as samples after removing all of the leaves. The water content of stalks and the variation of soil moisture were measured on three plots described below. One third of the samples were measured as soon as possible after the cutting and one third were 2 days after. In the remained sample the bottom of the stalks were soaked in water for 2 days and then the samples were used for experiment. The procedure of the measurement was the same with that describctd in the previous report. Results obtained are as follows. 1) The water content of the stalk was found to be different according to the growth stage, especially in the harvesting stage, it was much lower than in the early growing stage. The water content of the stalk in rainy day was higher than in clear day. 2) The water content of the stalk was different by stalk position and in the top of the stalk, it was higher than in the base. 3) The bending stress showed different values with tlle different water content through out all stages and some differences in the stalk breakage were observed in connection with the water content of the stalk. 4) From these results that the stalk breakage is increased when the weather is wet and loose, the auther suggested a method to prevent the damages of stalk breakage by film mulching practice.

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1. The object of the experiment was to study the growth of adventitious roots from the epicotyl or hypocotyl of winter legumes. Eight species (broad bean, pea, lupin, red clover, subclover, Egyptian clover, common vetch and Chinese milk vetch) were examined under the three methods of cultivation i. e. a standard cultivation, mulchirlg, and deep sowing (6cm below soil surface). 2. In broad bean, the roots developed adventitiously from the epicotyl even under the standard method of cultivation (Table 1 and Fig. 1), although fresh weight of the adventitious roots was only 5 % of the total root weght. Under both mulching and deep sowing, development of adventitious roots was marked (Fig. 2 A-E), particularly, in the plot mulched at the time when fourth leaf on the main stem spread out (Fig. 2-A). 3. Adventitious roots did not developed on neithdr pea nor common vetch except the deep sowing treatment (Fig. 3). 4. A large number of adventitious roots developed from the hypocotyl of lupin after flowering (Fig. 4-C), it would be caused by heavy rain. Clovers and Chinese milk vetch have a large and deep tap root compared with other species but very few adventitious roots developed (Fig. 4-D). 5. Among factors which influence the adventitious roots were considered to be: secondary thickening growth of the epicotyl or hypocotyl (Table 3 and Fig. 3) and the type of root system. The close relation between the growth of adventitious roots and that of secondary thickening of the epicotyl or hypocotyl was recognized. In broad bean with vigorous growth of the secondary thickening, the adventitious roots greatly developed and in pea or common vetch belonging to the little thickening type, the adventitious roots hardly developed. On the other hand, in spite of Chinese milk vetch and clovers belonging to the extensive thickening type, the adventitious roots did not developed. This would be related to the root system with big and deep tap root.

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1. In the present study, differences in secondary thickening growth of the main roots were observed using sixteen species. The soil was uniformly prepared and seeds were sown at l.5cm depth. 2. Table 1 gives the diameter of the main roots at 5cm intervals from the base of the root measured at various stages of their growth. From the data, it appears that the activity of the secondary growth is greatest at the base and least near the root tip of the root. The degree of secondary thickening growth varied according to the species; from 20 to 5 mm at the base of the main root. 3. The form of the main roots in the final growth stage are shown in figures 1 and 2. In some species (type A), secondary thickening growth extended to the whole length of the root, in others (type B), thickening occured mainly at the base of the root, whilst in type C there was little thickening from the base to the tip. 4. From these data the main roots have been divided into the following three types: A. Extensive thickening growth type (or Alfalfa type) B. Basal thickening growth type (Soy bean type) C. Little thickening growth type (pea type)

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On the way to comparative studies of the deformities caused by gibbefellin treatment in the spikelets of 17 rice varieties, the writer take the methodological position that the developmental studies of deformed spikelets are basically important in order to interpret scientiftcally the morphological nature of such spikelets, classify them systematically and to understand their developmental physiology experimentally. Since we have only fragmental knowledge on the development of deformed spikelets the constitution of them was analyzed theoretically and some hypotheses were drawn as follows. 1) The hypothesis on the development of normal spikelet : The apical meristem of spikelet primordium normally degrades right after the differentiation of a lemma primordium on it and then the other floral organs, these are, a palea, two lodicules, six stamens and a pistil, differentiate successively on the floral primordium initiated from the axil of the lemma primordium. This spikelet primordium generally develops in the normal spikelet that has the constitution as shown in model N (fig. 3-5.) The axis of the spikelet is not single but consists of two axes namely a spikelet axis and a floret one. The floret axis is a branch initiated from the axil of lemma on the spikelet axis. The palea corresponds to a prophyll on the floret axis in it's morphological nature and the two empty glumes do "sterile Iemma" on spikelet axis, two rudimentary glumes do the so-called "glume" on spikelet axis. Since the apical meristem degrades soon after the differentiation of a lemma primordium it is expected that the tip of main vascular bundle in spikelet axis exists in the region of the axis between the upper empty glume and the palea. 2) The hypothesis on the development of deformed spikelets : So far as the writer's observations in this study, the deformed spikelets are of two kinds. The spikelets of first group (Group I of the deformed spikelets) have the constitution (of a floret and those of second group (Group II of the deformed spikelets) have the constitution of bi-florets. a) On the development of the spikelets in group I. When the floral organs differentiate irregularly on the floret primordium under so me abnomal conditions, the spikelet primordium develops in a spikelet having variform floret. The typical variations observed in these spikelets are as follows. (i) The variations in the nerve number are from 1 to 6 in lemma, from 2 to 5 in palea (figs. 2-10, 14). (ii) The variations in the number of stamens are from to 0 and l0 (fig. 2-13). (iii) The variations in the number of pistil are from 0 to 3. There are various mediate types of multi-pistils. b) On the development of the spikelets in group II. When the apical meristem degrades after successive differentiation of two lemma primordiaon it, the spikelet primordium develops in a spikelet having bi-florets constiution because two floret primordia can be born on each axil of two lemma primordia. Though the spikelet primordium has a potentiality to develop two perfect florets in it (model II fig. 3-2), as differentiation of floral organs on each floret primordium takes place under various abnormal conditions in actual state, generally it can not have two perfect florets. Usually the lower florets are almost imperfect (figs. 2-6, 3, 4, 2, 7, 8) and the upper florets are perfect (fig. 2-4) or more (dominant than the lower ones (figs. 2-9, 12). Thus all of these spikelets are explained as modified types of the model II shown in fig.3-2 consistently.

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Experiments were carried out form 1967 to 1969 in a double cropping area of West Malaysia using five varieties, i. e., Ria (IR 8), Mahsuri, Bahagia (sister line of IR 5) and two local long term varjeties under three fertilizer levels. The results obtained are summarized as follows : 1. Short term varieties showed shorter plant height and culm length and smaller straw weight but greater number of panicles than those of long term varieties(fig.1). The peak of LAI in Ria was observed at the heading stage rather than the stage of young panicle formation. The adverse tendency was found in the other varieties, particularly two long term varieties.The culm length, LAI and N percentage in the straw tended to increase when the fertilizer increased, though the number of panicles showed less increase in the long term varieties than short term varieties. The correlations between LAI, and rumber of palicles and spikelets per sq. meter, and also correlations between grain yield, and number of panicles and LAI were found respectievly (fig. 3). 2. In the double fertilized plots, Ria and Bahagia were short in the culm length but higher in the grain/straw ratio and ratio of yield increase over non-fertilized plot among five varieties (table 1). It was found that LAI at the heading stage was correlated to the dry matter increase after heading, and the dry matter increase per unit leaf area was also correlated to the ratio of yield increase. This could be attributed to the better balance between photosynthesis and respiration and also higher contents of nitrogen in the the steaw in Ria and Bahagia (table 1). The grain/straw ratio was regarded as an index of fertilizer response. It also showed a definite relation to the culm length, i. e., the shorter the culm length the higher is the grain/straw rstio. 3. In a double cropping pilot project area, Ria gave grain yield 22 % more than Mahsuri, due to the high percentage of ripened grains and heavy weight of 1, 000 gains (table 2). The average yield of Bahagia in 19 farmers' fields was 10% higher than Ria, due to the high percentage of ripened grains (higher than Ria by 19%); though the number of panicles and spikelets per sq. meter were less with Ria. 4. It can reasonably be considered that the number of panicles per unit area contributed greatly to the yield, and the number of spikelets per unit area also contributed to the yield through the increase of panicle number by the denser planting (fig. 4). The weight of straw was also highly correlated to the number of spikelets and yield particularly in Ria. The percentage of ripened grains was also regarded as an important factor to increase yields (fig.4). It is very likely that Ria expresses the highest yielding ability under heavy fertilized conditions rather than with dense planting, although it has a defect of low percentage of ripened grains under adverse field conditions. Bahagia expresses a high ripening ability in the farmers' fields, although it has a limitation in increasing yield due to lodging. 5. It can be said that Ria and Bahagia are the most desirable varieties as far as yield and fertilizer response are concerned (fig. 2). The two long term varieties show the luxurious growth, resulting in the poor fertilizer response and low yield.

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With a view to diagnosing the rice cultivation by morphological observation of adult panicles, the authors investigated the occurrence of elongated bracts at the neck-nodes of panicles and its cause. Generally speaking, the bract can clearly be recognized at the panicle initiation stage under a microscope, but they mostly degenerate in the processes of panicle developement. In few cases, however, they elongate instead of degeneration and they can clearly be observed with the naked eye at the neck-node of adult panicles. The results of the present investigation can be summarized as follows. 1. Elongated bracts at the neck-nodes can be classified from their lengths and shapes into 5 groups as shown in Fig. 1. In the present paper, however, C, D, E are taken as elongated bracts and O, A and B are considered as degenerated bracts. 2. A number of varieties (111) have been investigated on the occurrence of elongated bracts. So far as the present investigation is concerned, no specific varieties have been found which are liable to produce the elongated bracts. 3. The conditions of fertilization such as the amount of basic fertilizers, the kind of elements (N·P·K) and the time of nitrogen topdressing have had no concern with the occurrece of the elongated bracts. 4. It has firmly been confirmed that lower irrigation water - temperatures than 20∼21°C, especially lower than 16°C, during the period centering around the first bract differentiation stage (approximately 33 days before heading) have closely been connected with the occurrence of elongated bracts, but a low air-temperature itself has no effect on the occurrence. (Since the growth points of rice plants are always under the water-surf at the first bract differentiation stage under the normal rice cultivation, if only a water-temperature is high, even if an air-temperature is considerably low, the growth points are not subjected to a low temperature and then the bracts never elongate. 5. From the study of developmental anatomy it has already been clarified in the previous paper that the elongated bract is the first bract which has firstly differentiated and abnormally developed at the neck-node. Accordingly, it is quite reasonable that the occurrence of elongated bracts is closely connected with the abnormally low water-temperature at the first bract differentiation stage, though the mechanism of the occurrence is not yet clear. Anyway, the occurrence of elongated bracts means in not a few cases that the rice plant have been subjected to a considerable low water-temperature during the period centering around the first bract differentiation stage.

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With the same purpose as in the previous paper (XCIX), the authors examined the usefulness of diagnosing the rice cultivation by the number of spikelets per primary and secondary rachis-branch, the panicle length (from the neck-node to the uppermost grain), the substantial panicle length (from the lowermost grain to the uppermost grain) and the density of spikelets per unit panicle length, obtaining the following results. 1. From the present investigation it has been elucidated that in the general rice cultivation in Japan the number of spikelets per primary rachis-branch, excluding the spikelets on secondary rachis-branches, is 5 to 6 and 5.5 in average, and that per secondary rachis-branch is 2 to 4 and 3 in average. Accordingly, if only the number of primary and secondary rachis-branches is known, the total number of spikelets on a panicle or a hill can easily be estimated. 2. The percentage in occurrence of primary rachis-branches which have 5 and less spikelets or 6 and more spikelets varies with cultivating conditions or environmental conditions, and the percentage of primary rachid-branches which have 6 and more spikelets can be considered as an index of the amount of nutriment per panicle or the goodness of environmental conditions at the spikelet differentiation stage, indicating that the higher the percentage, the better in nutrition or in environmental conditions. 3. The number of spikelets per secondary rachis-branches can also be used for diagnosing the rice cultivation as above, but sometimes secondary rachis-branches are liable to degenerate and therefore it is less important than that per primary rachis-branches, and it is best used as a supplementary means. 4. The length of panicles or the substantial length of panicles can also be considered as an index of the amount of nutriment per panicle or the goodness of environmental conditions during the period from the stage of first bract differentiation to the final stage of reduction division, indicating that the longer the panicle, the better in nutrition or in environmental conditions. 5. The rice variety has its own characteristic density of spikelets per unit panicle length. However, even if an identical variety is used, the density varies markedly with nutrimental or environmental conditions during the period from the final stage of vegetative growth to the final stage of reduction division. 6. However, the density varies also with the interrelation between the length of panicles and the number of spikelets per panicle as shown in Table 7. Therefore, when a given variety has not its own characteristic density, an examination of the interrelationship shown in Table 7 will give further information about the diagnosis of rice cultivation. 7. From the actual instances obtained from the weather-response experiments in various prefectures it has been confirmed again that the morphological characterlistics on adult panicles above mentioned can effectively be used for the diagnosis of rice cultivation.

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