In this report, the dark response of Japanese cucumber plant, as related to the differentiation of the flowers, is dealt with.
Short day plants, responding to the dark treatment, differentiate flower buds. In cucumber plant, at the first step, differentiate the staminate flowers and later the bisexual and further the pistillate flowers. It seems that a flower forming substance, at lower level, induces the staminate flower differentiation and at higher level bisexual and further the pistillate flower differentiation in the cucumber plant.
Seedlings tend to respond to dark treatment much more sensitively as they grow older. Since the green leaves are the organs which perceive the photoperiodic stimulus, it is due mainly to the increase of the foliage leaves both in number and area.
The minimum length of the dark period needed for inducing pistillate flower differentiation in the cucumber plant varies from 8 hours to 12 hours relating to the repeated photoperiodic cycles. For the pistillate flower differentiation, nine replications of 8 hours dark period are needed and three replications of 12 hours dark period suffice in its turn.
Exposed to long-day and under higher temperature, there are formed fewer staminate flowers per cluster, and the buds are liable to drop. Less production and transfer of the flower forming substance seems to suppress, in this cace, the development of the staminate flowers.
The number of pistillate flowers increses with lengthening the dark period to 18 hours but decreases when dark period exceeds 20 hours. Few pistillate flowers are formed under 22 hours dark period and no pistillate flowers under 24 hours dark period. Pistillate flowers are induced when the dark period is adequately long but not too long. Light and dark periods have to follow cyclically and more repetitions of the cyclic treatments induce more abundant pistillate flower differentiation.
Dark period interrupted by one hour lighting at the middle of 16-hour dark period showed the same effect to induce the pistillate flower differention as the identical length of dark treatment uninterrupted by the interposed light period.
With an adequate length of dark period, light irradiated through blue cellophane and double cellophane, blue and red, induced no pistillate flower differentiation. Light filtered through red cellophane induced pistillate flower differentiation.
Light intensity and wave length, to same extent, are the factors in this process.
The influence of the day length is modified and sometimes counteracted by temperature (including diurnal alterations in temperature) before, during, and after the dark period.
Seedlings brought up under medium temperature form more pistillate flowers when they were exposed to adequate dark period than those brought up under higher temperature. The number of pistillate flowers formed on the seedlings are in the following descending order: 24°_??_17°C (day versus night temperature during the nursery-bed), 24°_??_24°C and 24°_??_32°C.
The optimal temperature during the photoperiodic treatment is 17°C and the optimal diurnal alteration is 24_??_17°C. At lower and higher temperatures, pistillate flower formation is reduced or absent. Above 32°C, no pistillate flowers were induced even after twelve repetitions of the photoperiodic treatment. In general, four to six repetitions are adequate under the optimal temperature.
The optimal temperature (day and night) during the light period extended by the electric lamp is 17°C. The higher night temperatures (17°C, 24°C and 30°C) reduced the pistillate flower differentiation.
Temperature during the photoperiodic treatment showed a profound influence on the pistillate flower differentiation. Below 17°C, plants even under continuous illumination, formed pistillate flowers.

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The objects of this study were to examine the varietal difference of tomato in fruit cracking, and to clarify the characters associated with the occurrence of cracking.
1. Most of the early varieties, such as Bonny Best and June Pink, showed a high percentage of, concentric and irregular crackings. In varieties having less cork layer on their fruits, such as Rot Köppen, San Marzana and Shugyoku, less radial crackings occurred. Concentric cracks developed quite frequently in the varieties having small leav es and exposed fruit clusters.
2. Occurrence of less radial crackings in Crack-Proof and _??_ 135 is considered to be due to high elasticity of fruit skin and to low sugar content of the fruits.
3. Occurrence of less concentric crackings in Crack-Proof and 63A311 is considered to be due to large leaves developing just above the fruit clusters.
4. It is concluded that for breeding strains with less fruit crackings it is desirable to select the plants having large leaves covering the fruit clusters, small stem scar on fruits, and with highly elastic fruit skin.

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Sapporo-ki male-sterile plants propagated vegetatively and male-sterile clonal lines introduced from the U. S. Department of Agriculture were crossed with a number of other varieties. The growth habit, bulb characters and keeping quality of those resultant hybrids were investigated in 1958 and 1959.
The results obtained are summarized as follows:
1. During the seedling stage the hybrids were taller than their parents and the vigor of the hybrid exerted great influence on the growth habits, consequently on the bulb weight and yield.
2. The number of leaves was increased in five crosses, bolting occurred in two crosses and a non tops-down type similar to Sweet Spanish onions was observed in six crosses among twenty seven combinations.
3. So far as the yellow onion crosses were concerned, the color of the foliage and bulb of the hybrids took an intermediate tint between the colors of their parents.
4. In most cases the hybrid required an intermediate number of days for attaining maturity between the two parents. In this case the date of maturity of the hybrid was usually earlier than the average maturity of the parents.
5. The shape of the hybrid bulbs was usually intermediate between the shapes of their parents. The uniformity of the hybrid bulbs was not very evident in 1958, but it was very remarkable in 1959, especially in the crosses where Sapporo-ki was used as the female parents.
6. The maturity and shape index of bulbs were closely corrected within a group of varieties of similar characters, but such a relation did not necessarily exist in groups of varieties of different characters.
7. Hybrid bulbs were not always heavier than those of their parents; in certain crosses the hybrid bulbs were even lighter than those of either parent.
8. The keeping qualities of some hybrids were intermediate between those of their parents in about half of the crosses; in the remaining half the hybrids were superior to their parents in this respect.
9. Downing Yellow Globe and Brigham Yellow Globe were excellent as the male parent in the combinations with Sapporo-ki; the resultant hybrid seeds were superior to the F₁ hybrids obtained from the U.S.A. and also better than the hybrids combined with the imported male-sterile lines.
10. In the case of crossing between the imported male-sterile line and other varieties, Sapporo-ki as pollen parent, gave a remarkable uniformity of bulbs. Brigham Yellow Globe×Sapporo-ki is a promising combination from the practical standpoint.
11. The hybrids among various strains of Sapporo-ki seemed to have a tendency to produce heavier bulbs. This problem is worthy of further investigation.

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The author investigated the interaction effect of temperature and humidity on trends of germination power of cucumber pollen after dehiscence. Pollen vitality decreases with increasing temperature in these experiments. Low humidity hastens the rapidity of losing germination power in all temperatures used. The harmful effect of saturated humidity on pollen vitality is greater at high temperature than at low temperature. The favorable humidity for longevity is 80% which is usual during summer in Sapporo. Rate of pollen germination in male flowers at 10°C. and 80% humidity was maintained high (over 50%) for a considerably long period (till 8 p. m. of the fourth day after flowering). Pollen vitality was increased by alternation from low to high humidity, while it was decreased by the reverse alternation from high to low humidity. A parallel relation was ascertained between results of pollination and germination tests on artificial media. Trends of germination power varied according to the starting time of treatment to low temperature.

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1. The aim of the present study is to find out some relation between nutritional accumulation and growth of muskmelon (var. Earl's Favourite) grown under the experimental condition reported in the previous papers. The design of fertilizer treatments is presented in Table I. The results obtained are shown in Tables 2 to 8 and in Figures 1 to 6.
2. Plant height increased rapidly during the five weeks after planting, and then remained constant until harvesting time. The greatest increasing Tate in fruit weight was observed between the second and third weeks after pollination when the fruit net appeared, while there was a great increase in soluble solids in fruit during the two weeks before harvesting time.
3. The amounts of nitrogen in whole plant increased up to the ninth week after planting, and then remained constant until harvesting time. The amounts of nitrogen in leaf increased rapidly during the five weeks after planting, and then slowly during the following four weeks, but decreased thereafter until harvesting time. Those in stem were less than those in leaf, while the accumulation processes in stem were analogus to those in leaf. On the other hand, its accumulation in fruit increased linearly throughout the entire growing period. From these results, it was found that a part of nitrogen in leaf and stem translocated from these organs to fruit during the two weeks before harvesting time.
4. The amounts of phosphorus in whole plant increased up to harvesting time. The amounts of phosphorus in leaf at the standard and low levels of nitrogen increased rapidly between the third and fifth weeks after planting, and then increased slowly until harvesting time, while those of the latter increased slowly between the third and seventh weeks after planting, and then remained constant until harvesting time. The accumulation processes in stem were analogus to those in leaf. On the other hand, the accumulation in fruit increased almost linearly throughout the entire growing period.
5. The amounts of potassium in whole plant increased in almost a linear pattern between the third and ninth weeks after planting, and then increased slowly until harvesting time. The amounts of potassium in leaf and stem increased up to the ninth week after planting, and then remained constant until harvesting time. On the other hand, its accumulation in fruit increased almost linearly throughout the entire growing period.
6. The amounts of calcium were greater in leaf than any other organs of plant and the accumulation in leaf showed almost a linear increase throughout the growing period. Moreover, decreased supply of nitrogen to the plant resulted in greater accumulation and percentage of calcium in leaf.
7. The amounts of magnesium were greater in leaf than in any other organs and those at the standard level were greater in leaf than those of other levels throughout the growing period. The amounts of magnesium in leaf increased up to the ninth week after planting, and then increased slowly until harvesting time. Moreover, magnesium accumulation in whole plant were analogus to that in leaf.
8. The accumulation ratios of phosphorus to nitrogen (100) in leaf and whole plant were about 30 to 50 throughout the entire growing period; those of potassium, calcium and magnesium to nitrogen increased rectilinearly up to fruit harvesting time. On the other hand, the highest ratio of all other elements to nitrogen in fruit was observed between the second and third weeks after pollination when the fruit net appeared.
9. The amounts of N, P₂O₅, K₂O, CaO and MgO in whole plant, at the low level which received ammonium sulphate and at the standard level which received rape-seed cake as nitrogen source were as follows. Those of the former were 6.2, 2.6, 18.5, 15.5 and 2.2g; those of the latter were 7.6, 3.1, 20.5, 17.2 and 3.5g per plant.

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From the standpoint of varietal selection for juice production, comparative studies on the growth, yield and pigment contents of tomato fruits were carried out with Experimental Farm of Shinshu University in Nagano Prefecture.
1. The plant heights of varieties Matsudoponderosa, Oogata-Akafuku and Fukuju-Ichigo were taller and those of Toohoku-Yongo, Jubiree and Shugyoku were lower than those of the other varieties. The number of nodes did not coincide with the length of stem.
2. It was observed through the varieties that the number of flowers increased in the higher flower clusters, but their fruit set decreased. Accordingly, the coefficient of fruit set decreased in the higher flower clusters. Varieties Shugyoku, Ponderosa and Aichi tomato had more flowers than the others. Variety Shugyoku showed the highest fruit set among the varieties observed, and its coefficient of fruit set on three flower clusters was 97.5 per cent.
3. The yield of each variety depended on the number of fruits harvested and the total weight of individual fruits. Variety Fukuju-Nigo showed the highest yield in 1958, and variety Oogata-Akafuku in 1959. Variety Shugyoku had the largest number of fruits harvested, but the weight of its individual fruit was only 50g. or less. Therefore the yield of the variety was the poorest among the varieties.
4. The measurements on the dry matter coefficient, viscosity, pH value, sugar content, hardiness and coloring in matured fruits were made. The coefficients of dry matter were higher in varieties Shugyoku and Matsudoponderosa. The differences in pH value ranging from 3.85 to 4.35 were not remarkable among varieties. The sugar contents were higher in Akafuku-Sango, Sekaiichi, Matsudoponderosa and Kiyosu-Nigo, and lower in Jubiree and Toohoku-Yongo than those in the others.
5. Lycopene contents were higher in Kikyoiku-Ichigo, Kiyosu-Nigo and Furuyawase in 1958 and in Oogata-Akafuku and Oogata-Fukuju in 1959 than in the other varieties. Lycopene contents of all varieties were higher in 1959 than those in 1958, while there were no differences in carotene and xanthophyll contents between the fruits produced in both years.

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As part of the studies on the salt tolerance of vegetable crops, seven leaf vegetables, namely, cabbage, spinach; Chinese cabbage, celery, onion, lettuce, and Japanese hornwort, were grown in sand cultures under glass at various concentrations of NaCl. HOAGLAND's solution was used as the basic solution (control), and the concentrations of NaCl added to it were 1000, 2000, 4000, 8000, and 16000ppm, respectively.
1. In spinaches, onions, lettuces, and Japanese hornworts, plants were dwarfed, and both the number of leaves and the fresh weight of tops were reduced with increasing concentration of NaCl. In cabbages, and celeries, however, the 1000 or 2000ppm treatment had favorable effects on the growth of plants and the fresh weight of tops. The plants died at the 16000ppm in Chinese cabbages and lettuses, and above 4000ppm in Japanese hornworts. The concentration of NaCl in the nutrient solution corresponding to a 50 per cent reduction in the fresh weight of tops was found to be about 9000ppm for cabbages, 8000ppm for spinaches and Chinese cabbages, 6000ppm for celeries, 2500ppm for onions, 2000ppm for lettuces, and 1000ppm for Japanese hornworts. In cabbages, the hard formation was a little delayed with the increase of salinity, and the heads at the 8000 and 16000ppm were less compact than those from the lower salt treatments, then the yield of heads was reduced by 50 per cent at about 6500ppm. In onions, bath the bulb formation and the maturing were not affected by salinity, except the 16000ppm treatment in which growth was especially poor, and the yield of bulbs was reduced by 50 per cent at about 2500ppm. In some crops, the dry weight percentage of tops increased slightly in higher salt treatments.
2. Specific symptoms of salt injury were as follows: In cabbages, the surface of leaves was temporarily waxy in the treatments above 2000ppm. In spinaches, leaves were entirely chlorotic at the 16000ppm. In Chinese cabbges, leaves were dark bluish green above 8000ppm, the plants died at the 16000ppm, and incurling of leaf margins generally occurred in all NaCl treatments. In onions, die back of leaves occurred starting from the older leaves in the NaCl treatments, which caused the complete die off of the leaves at the 16000ppm. In lettuces, leaves were dark green at the 4000 and 8000ppm, while leaves were entirely chlorotic and subsequently the plants died at the 16000ppm. Celeries and Japanese hornworts developed no specific symptoms, but the latter died above 4000ppm.
3. With increasing cocentration of NaCl in the nutrient solution, both Na and Cl were accumulated proportionaly in the leaves of most crops, and more tolerant crops tended to accumulate more Na. Except in Japanese hornworts, Na accumulated in leaves in greater equivalent amounts than Cl. In general, antagonistic relations were found between Na and other cations, i.e. K. Ca and Mg, intensity of which, however, varied with the ions or vegetables, and the total amount of these four cations in leaves increased with increasing of NaCl in culture solution in most crops. The contents of N in leaves, except in cabbages, tended to decrease in the NaCl treatments. The effect of the NaCl treatments on the contents of P in leaves was variable with the vegetable species. But the variation of the contents of N and P was rather slight as compared with that of cations. There was no such definite tendency in the variation of carbohydratee contents in leaves.

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1. During 1959_??_1960, an experiment was conducted for examining the response of a cabbage variety (Yoshin) to seed-vernalization.
2. Seeds vernalized at 1 ± 1°C for 20 days were sown along with untreated control seeds four times at 10-day intervals from March 14 to April 13, 1959. Further on December 2, an autumn sowing was made under the same treatment scheme.
3. In the plot seeded March 14, all plants grown from vernalized seeds (V20) bolted, flowered and in September produced viable seeds, whereas only one out of ten control plants (Vo) managed to flower but never went to seeds, the remainder producing heads.
In the plot seeded March 24 and April 3, neither vernalized nor control plants bolted but headed normally, yet the microscopic observation demonstrated that the flower-bud differentiation was remarkably accelerated in the vernalized plants.
In the plot seeded April 13, no flower-bud differentiation was observed in the plants as a whole. In August, both of vernalized and control plants produced normal heads.
In the autumn sowing, December 2, any significant difference in development was not seen with respect to vernalization treatment. In the plants grown from vernalized and control seeds initiated floral differentiation concomitantly at the beginning of February in the next year, though the further development was greatly variegated with individual plants in both lots, some of which never flowered by the end of June.
4. The cabbages (Brassica oleracea spp.) are known to have to reach a certain minimum age before they can be made to flowering by cold. In other words, they must pass a “juvenile phase” before flowering can be induced.
Our present experiment, however, suggested that at least a certain of cabbage varieties is sensitive to cold even in its earliest stage of growth just after the germination.
The results of our work still exhibited that the effect of seed-vernalization in itself is never sufficient for complete induction. Seed-vernalization leads to flowering only when interacting with plant-vernalization given to the plants in their growing period. So, the effect of seed-vernalization is visualized in so far as plant-vernalization has a suboptimal results owing to age of plant or to too short a cold period.

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A strain of Satsuma orange (Citrus unshiu) was rebudded on three different strains of Satsuma oranges, Yuzu (C. junos), and Tachibana (C. tachibana) in September, 1939. These interstocks had been budded on trifoliate orange (Poucirus trifoliata) rootstocks in September, 1937. The scion was the same strain as one of the interstocks of Satsuma. In April, 1959, these double-worked trees were all dug out and every part of them was weighed. The effects of the interstocks on the tree growth, fruit quality and yields for the ten years after the previous report were investigated. The results of the present experiments are summarized as follows:
1. The interstock of a dwarf Satsuma strain (Nods) showed less vigor of the top, less yield, and less growth of rootstock than those of a vigorous one (Tanikawa). These tendencies have become more conspicuous as the age of tree increased.
2. The tree growth and yield on the interstocks of the Satsuma strains other than the one used as the scion were less than those of the trees on Satsuma interstock of the same strain as the scion.
3. The Satsuma top on Tachibana interstock showed rather vigorous growth and larger cropping, while that on Yuzu interstock showed the poorest growth and the least cropping, and the trifoliata stock in this combination also showed very poor growth. The older the trees the more differences there were.
4. There were hardly any differences among the plants with different interstocks in the size, the coloring time, and the quality of fruit, excepting that plants with Yuzu interstock produced somewhat small fruits.
5. It was shown that the scion and the interstock had united well and the united part had uniformly grown on the interstock of three Satsuma strains. However, a marked swelling at the base of scion was seen on Tachibana interstock, while the scion on Yuzu interstock was more slender than the interstock itself.
6. When the bark of the trunk was removed, the woody tissue of Noda strain (one of the Satsuma interstocks) showed a distinct fissure at the bud union between the interstock and the rootstock, and then, the fissure splitted rather deep as the wood dried up.
The other four interstocks showed no distinct symptoms at the bud union, although a marked overgrowth of the trifoliata rootstock had been seen in all tested trees, as usual.
7. All the interstocks of Tachibana and some of Yuzu showed a distinct stem-pitting like the symptom of tristeza at the part of interstock, but it was supposed to have no direct relation with the vigor of the tree.

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Removal of astringency of Japanese persimmon fruits by freezing was tested with fruits of thirteen varieties holding in the freezers of various temperatures. The samples were taken out periodically for measuring their soluble tannin contents. Soluble tannin in the frozen fruits decreased gradually and disappeared in 10 to 90 days with a varietal difference in a similar order as treated with carbon dioxide. As to the freezing temperature, -25°C was most effective, -75°C medium, and -12°C least.
Results of some experiments on the mechanism of removal of astringency by freezing seemed to show that the disappearance of astringency was not induced by the change of chemical property of tannin, but rather had some connection with dehydration of the colloidal substance in which tannin was held.

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Observations on the growth cycles of roots, shoots, and berries of grapes were undertook at the vineyard of Kotobukiya Institute of Viticulture near Kofu city from 1955 to 1957. Materials used were nonbearing and bearing vines of Black Queen variety.
1. Root growth started in the latter part of April and reached its height in new root formation and elongation in the middle and latter parts of July. It had another peak in the latter part of October, and was observed to be rather restricted between the two peaks. Its growth was ceased from the early part of December through the middle of April in the following year.
2. Shoot growth started in middle April with emergence of buds, and was the most vigorous from early June through middle July. Its growth was ceased in middle September.
3. Berry growth was the most conspicuous from late July through early August.
4. Growth cycle of the grapevine as a whole was shown to be made of the following sequence (Figs. 1, 2 and 3) at first shoots started to grow, root growth followed, then berries made a rapid growth. After the berries matured, the second peak of root growth occurred, then the vine lost its leaves and became dormant.

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This observation was conducted to obtain anatomical and morphological aspects of primary root and tuberous root in dahlia.
1. The primary root has a tetrarch protostele, and four groups of small phloem cells alternate with the primary xylem strands, and the pith is in small proportion.
2. The first adventitious root appears on the basal part of the cotyledon, when about 4_??_8 leaves are opened on the stem.
Thereafter, as the plant develops, adventitious roots successively appear (until the number reaches 20_??_35) on the cotyledonary node and lower nodes of the stem, these portions are commonly called the crown.
3. These adventitious roots have radial vascular bundles of 12_??_30 strands and pith of relatively large volume. These are the so-called polyarch vascular bundles.
In the adventitious roots the secondary xylem is formed by cell division in the cambium and secondary meristem near the vessels.
4. The thickening of adventitious roots is brought about by the cell division mentioned above and by the elongation of these cells, then adventitious roots develop into the tuberous roots.
5. Degree of the thickening of adventitious root is related to the number of rings of secondary vessels and to the area of pith tissue, while the diameter of adventitious roots is not correlated to the number of primary xylems.

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Cormels of gladiolus, Spotlight variety, were planted in wooden boxes (20×25×18cm) with sand, on March 26, 1956. After the cormels germinated, they were thinned to 6 plants for each box. The nutritional treatments were made from May 6 to August 7 by the following design.
plots: control, 1N1P1K, 2N1P1K, 4N1P1K, 1NIP2K, 2N1P2K, 4N1P2K, 1N2P1K, 2N2P1K, 4N2P1K, 1N2P2K, 2N2P2K, and 4N2P2K. 1N 50ppm
1P 25ppm 1K 40ppm
Three replications were made for each treatment, and one liter of nutritional solution was applied to 3 boxes of each treatment at 3-day intervals. The results obtained are summarized as follows
1. The earliest flowering was seen in the 1N2P 2K plot and the latest was in the 4N1P2K. In general, the average flowering date delayed as nitrogen application increased.
2. The percentage of flowering 61.1% was highest in 4N2P2K plot, lowest 11.8% in 4N1P1K and the average percentage was 37.7%.
3. The percentage of blind stalks was 11.8% in 4N2P1K, and the percentage of unflowered stalks. was 5.9% in 4N1P1K and in 4N2P1K. The percentage of undifferentiated plants was highest in the control (100%), lowest in 4N2P1K (35.2%), and the average percentage was 60.4%.
4. On the number of leaves, significant differences were observed between the treated and untreated plots, but not among treated plots. On the number of florets on a spike, no significant difference was observed among plots.
5. On the height of plants, weight of tops, and weight of new corms, 2N was the highest and heaviest of all.
6. Weight of root and number of cormels decreased with increasing nitrogen. And weight of cormels decreased with increasing nitrogen in 1P plots, but 2N was the lightest among the three N levels in 2P plots.

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