Because of the fact that there were recently found nutritional disorders of Chinese cabbage which seemed to be due to calcium deficiency, in some areas, several experiments were carried out by means of water culture to clarify symptoms of cal-cium deficiency in Chinese cabbage and also to elucidate the effect of composition of culture solution on its occurrence.
1. Symptoms of calcium deficiency in Chinese cabbage: When appear before heading, the tip mar-gins of green leaves show water-soaked and trans-parent appearance, then rapidly wilt and collapse into dehydrated white band. This symptom is the same as the so-called Fuchigusare (marginal rot) found in the field. Both troubles can be prevented by the spray of calcium salt solution. Consequent-ly, Fuchigusare has been proved to be due to calcium deficiency.
When calcium is deficient after heading, the mar-gins of head leaves become water-soaked like and transparent, then turn light brown and soft-rot due to the secondary invasion of rot bacteria. As to the identification of Shingusare (heart rot), the occurrence of which is rather prevalent and more serious than Fuchigusare, the similarity of its symp-tom with that of calcium deficiency after heading, the low calcium content of rotted leaves as well as the observations on the conditions of its occurrence show the possibility that it is due to nothing but calcium deficiency in spite of the failure of cal-cium spary to prevent it.
2. Low calcium concentration, high salt concen-tration of medium and NH₄ used as a part of ni-trogen source, all of these decrease calcium absorp-tion by the plant, and this decrease is responsible for the appearance of calcium deficiency. Calcium content of head leaves, however, is markedly low even in the normal plant irrespective of its high content in the lower, green leaves. Moreover it does not necessarily reflect closely the decrease ofcalcium absorption on the whole, especially when analysis is made including midribs.
3. NH₄ used as a part of nitrogen source decreas-es the absorption of calcium, magnesium and potassium, and increases that'of nitrogen and phos-phorus by the plant.
Under high salt concentration as a whole, the absorption of calcium as well as of magnesium de-creases consistently regardless of the simultaneous increment of them in the medium, while the ab-sorption of nitrogen and phosphorus does not show any definite trend andthat of potassium is much influenced by K/N ratio in the medium, that is, decreases following low K/N and increases follow-ing high K/N.
4. The echanism of decreased calcium absorp-tion in relation to the occurrence of calcium deficien-cy in the field and pot culture and also the pecu-liarity of calcium deficiency symptoms were discus-sed.

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The purposes of the present study were to in-vestigate the effect of nitrogen and calcium forms on the fruit quality and the absorption of nutritional elements in muskmelon. The levels of calcium were also investigated. Plants of the variety Earl's Favourite were grown by the method reported in the previous paper. Details of the design of ferti-lizer treatment are presented in Table 1. The re-sults obtained are presented in Tables 2 to 7, inclu-sive.
1. The main effects of increasing the level of calcium were to promote the vigorous growth, to increase the leaf, stem and fruit weights, to im-prove the external appearance, to increase the pH value of soil, to increase the nitrogen, phosphorus. calcium and magnesium amounts in the whole plant, to increase the percentage of calcium in various organs of the plant, and to decrease the percentage of nitrogen in leaves, stem and roots.
2. The main effects of nitrogen form were: NO₃-N form increased the fruit weight, increased the pH value of soil, inhibited the vigorous growth, decreas-ed the nitrogen and potassium amounts in the whole plant, increased the calcium amount in the whole plant, and decreased the percentage of nitro-gen in various organs of the plant.
3. The main effects of calcium form were: CaCO₃ form increased the nitrogen, phophorus, potassium and calcium amounts in roots.
4. Some interactions were obtained from the variables.
5. No significant effects were shown by any of the nitrogen and calcium forms on the growth and fruit quality.
6. The plants which received 40 to 80g CaO per plant were able to maintain vigorous growth and produced fruits of high quality. Judging from these results, the recommendable amount of calcium application is 40 to 80g per plant.
7. The amounts of N, P₂O₅, K₂O, CaO and MgO in the whole plants resulting from receiving 40 to 80g calcium were 4.8 to 4.9, 2.4 to 2.5, 8.7 to 8.9, 10.1 to 10.7 and 1.6 to 1.7 g per plant, respec-tively.

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The absorption of nutrients at different stages of growth of head lettuce (Great Lakes) was studied using plants grown in sand supplied with the solution containing 200ppm of N, 50ppm of P, and 100ppm of K.The peak of absorption rate occurred coinciding with the stage of the most rapid growth: this fell within the two week period around the starting of head formation. The total amounts of nutrients absorbed were N 1.19g, P 0.32g, and K 0.77g per plant.
To elucidate the effects of nitrogen and potassium levels and their balance on the growth of lettuce, plants were grown in 12 plots given 100, 200 or 400ppm of nitrogen with 0, 50, 100 or 200ppm of potassium. With regard to the nitrogen level, the growth was best in the plots given 400ppm of nitrogen regardless of the potassium level. As to the potassium level, however, the optimum concentration for the growth varied according to the concentration of nitrogen.
Nitrogen content of the head leaves in the plots. in which high yields were obtained ranged from 3.0 to 3.5%.
The optimum potassium content differed according to the nitrogen level. Nitrogen and potassium contents in the N-400, K-100ppm plot in which the highest yield was obtained were 3.03 and 1.7%, respectively.
Analysis of head leaves of the lettuce produced by some growers showed that the nitrogen contents were within the range mentioned above, but the potassium contents were much higher than the, value which was sufficient for obtaining high yield in the sand culture experiment. Therefore, it is assumed that the growers may be applying excessive amounts of potassium to the lettuce in their field.

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Following the study reported in the first paper of this series, some observations were made on the flower-bud differentiation, flowering and fruiting of “Issun” broad bean (a large seeded variety) at the Awa Branch of Chiba Agricultural Experiment Station in 1955-56.
The first sign of flower-bud differentiation was observed in middle November, 38 days after the planting or 15-20 days after the average daily temperature failed below 15°C. The plants had two or more fully developed leaves at that time. Although, as a rule, flower buds were observed earlier on the branches developed in early stage, they were slightly retarded on the main stems and the first laterals.
Once differentiated, flower buds developed rapidly and formed pollen mother cells in the end of December. Then they suspended their development during the winter till the end of February, when they resumed their active growth to blooming.
While the first blooming occurred on the third branch, the largest number of flowers and pods were obtained on the sixth branch. When branches were thinned to six per plant, the blooming was accelerated and numbers of flowers and pods were increased on the remaining branches.
This fact seemed to show that there was a competition for nutrients among the branches. Relatively low productivity of the branches developed earlier was due to their susceptibility to winter injury. High productivity of the branches of rather higher orders seemed to owe to the fact that they developed when the internal conditions were most favorable and took dominance over the other branches.

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Studies on the measurement of pigment contents and some characters of tomato fruits covered with red, green, blue or black cellophane bags, or black, red, white or transparent vinyl bags have been carried out at Department of Agriculture, Kyoto University and Shinshu University in 1958.
1. The tomato plants were cultivated with the fruits covered with cellophane bags till Aug. 11. The fruits were then stored in the storage rooms maintained at 10°C and 20°C under an artificial light, and in the glasshouse of phytotron where the illumination by artificial light was added to the natural day light during the night, and the temperatures of 20°C and 30°C were maintained.
The content of pigments in the fruits depended upon the temperature stored, but not upon the difference of color of bags. The fruits stored at 20°C had a larger amount of pigments than the others, especially the fruits stored in glasshouse with artificial light showed the largest amount of pigments.
2. The microscopical observation of chlomoplasts revealed many yellow granular masses in the flesh, of outer part of fruit and needle-shaped pink crystals of lycopene in the flesh of flower-end and core of fruit. Especially, the flesh of core has the largest amount of lycopene.
3. During the cultivation of tomato plants, the maturity of fruits covered with vinyl bags of various colors was studied. The fruits covered with transparent vinyl bags required less number of days to mature. On the contrary, the fruits covered with black vinyl bags required more number of days to mature.
4. From the results of measurement of pigment contents in the fruit 35, 60 and 55 days after anthesis, the fruit covered with white vinyl bag had the largest amounts of chlorophyll, carotene, lycopene and xanthophyll among the lots. On the contrary, the fruits covered with black vinyl bags had the smallest.
5. All pigments contained in fruits were affected by the interception of light to the fruits. Carotene is the most affected, and lycopene is the least among the pigments. The light intensity enough for pigment development is considered to be about 30% of natural day light.
6. All fruits covered with various vinyl bags were smaller in size and weight than the control. Especially, the fruits covered with black or transparent vinyl bags were smaller in size and damaged. While, the fruits covered with white bags were as good in their quality as the control. The control fruits showed much higher percentages of dry weight and higher pH values than the fruits treated. However, the fruits covered with white bags had higher sugar contents than the others.

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In the previous paper, it was reported that the most desirable temperature for the storage of fruits of Fuyu variety was 0°C. The present experiment was made to investigate the practical effects of several packing materials on the weight loss and shriveling, growth of microorganisms and lengthening of storage period by maintaining a proper constitution of .atmosphere around the fruit. Post-ripening and, deterioration at room temperature after removal from cold storage were also tested. The sample fruits were obtained from the Kagawa University farm on November 13, and 27, 1958. These fruits were kept at room temperature overnight, then packed and stored on the following day at 0°C and 85_??_90 per cent relative humidity. Seven experimental items were studied: 1. control, 2. packing with excelsior in wooden boxes, 3. packing with rice hull in wooden boxes, 4. packing in sealed desiccators, 5. packing in polyethylene bags of 0.03mm, 6. packing in polyethylene bags of 0.06mm, 7. packing in polyethylene bags of 0. 08mm. The dimensions of polyethylene bags were 14×28 cm and three persimmons were packing in each bag. The results are as follows.
1. The fruits both in polyethylene bags and in desiccators lost only 1 per cent or less of weight, while in control (1), packing with excelsior (2) or with rice hull (3), the loss was 6_??_7 per cent in weight after 2_??_3 months. The fruits became visibly shriveled and spongy-like in its texture when it lost 5 per cent of weight.
2. Carbon dioxide content within the polyethylene bags and desiccators rapidly increased during the early storage period, and reached 5 per cent (in 0.03mm polyethylene bags) to 50 per cent or more (in desiccator) after I month. In the polyethylene bags of 0.08mm and desiccator, the carbon dioxide accumulated to a dangerous level and the fruit showed physiological damage in a longer storage period.
3. The advance of after-ripening and deterioration of Fuyu fruits sealed in the polyethylene bags was slower than that in open bags when moved out to room temperature from the cold storage, and the polyethylene bags of 0.06mm retarded the after-ripening most effectively.
4. On the basis of these results, a temperature of 0°C, relative humidity of almost 100 per cent and combinations of 5 per cent carbon dioxide and 5_??_8 per cent oxygen seem to be the optimum conditions for the storage of Fuyu fruits. The most successful method of storing was to pack them in polyethylene bags of 0.06mm and then to store them at 0°C.

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Japanese persimmon trees make poor growth very often in the first growing season after they are transplanted into the field. It is said that one of the causes of this trouble is due to the delayed and poor growth of new roots from the transplants.
In this study, application of potassium α-naphthaleneacetate, a growth regulator, was made in an, effort to overcome this trouble by promoting the new root development of the transplants. Oneyear-old persimmon seedlings were dug up and all their fine roots were trimmed off. Some of the seedlings were treated by soaking their roots in the growth regulator solution of 0.001 to 0.05% for 24 hours (dipping method). Others were treated by applying the solution of 0.005 to 0.01% into the soil once or twice after they were planted in the soil (soil application method). The check plants were dipped in tap water for 24 hours. All the plants were grown in an unheated glass house for protecting them from frost. In June, their roots were washed out for the observation of new root development.
The growth regulator treatments accelerated neither the opening of buds nor the unfolding of leaves. The treatments, however, promoted the elongation of new shoots and increased the size of leaves (Fig.1). These effects were significant from an early stage of growth.
The treatments induced earlier development of new roots, and markedly increased the number and weight of new roots (Fig. 2).
The dipping method was more effective than the soil application method. The higher the concentration of the growth regulator solution, the greater was the effect, up to 0.05%, the highest concentration used in this study.

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1. To study the bionomics of smaller oreasia, investigations on its rearing in the laboratory and observations of moth emergence in the field were conducted at Kibi-cho, Arida-gun, Wakayama Prefecture where the annual avervage temperature is 16.7°C.
2. The relations between the temperature and the number of days required for growth of egg, larva and pupa are shown by two linear lines in Table 7.
3. The maximum survival period of adult in rearing tests in October was 34 days in female and 40.5 days in male. The maximum number of eggs laid was 862 in July when reared on tomato.
4. There was not much difference between the result of the rearing test in laboratory and that of the observation in the field, and although four gene rations were repeated normally, some ended in three generations. According to both investigations, the appearance of each stage was as follows
Egg; late May-middle June, middle July-early August, late August-late September, and middle October-early November.
Larva; early June-early July, middle July-late August, early September-late September (or early September-overwinter-early May), and late Octo ber-overwinter-early May.
Pupa; early July-middle July, early August early September, late September-middle October, and late April-late May.
Adult; early July-early August, middle August late September, middle Septmber-late November, and early May-early July.

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This experiment was carried out to investigate the effect of day-length on the flowering of dahlia in 1959. Each one variety was selected from four strains, Single, Decorative, Cactus, and Pompon.
Three different conditions, long, natural and short, day lengths were given to each variety. Plants were illuminated by the incandescent lamp of 100 watt per 6m² during night in the long day lot, and were covered with black plastic film from 5 p.m. to 9 a.m. in the short day lot. Tubers were planted in pots on April 15. The day-length treatment started on June 1, The plants of Single and Pompon varieties showed flower buds in every lot, while the plants of Cactus and Decorative showed few flower buds in the short day and natural day lot on June 22. On this day, all main and lateral shoots of each plant were curtailed. Then, the conditions of day-length were changed into the following combinations: L→L, L→N, L→S, N→L, N→N, N→S, S→L, S→N, S→S.
After changing the condition, the observation of flowering was done. All plants of Single and Pompon varieties showed the flower buds by August 21. However, normal flowering was seen in Single strain alone.
Among all the lots, the plants which were given short day-length before or after June 22 showed higher flowering percentages, while the plants Which were given N→L or L→L combination showed poor or no flower buds.

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1. The frost-hardiness of bulbs and tubers varies according to their stages of development and internal conditions. The bulbs and tubers of tulip, lily, crocus, hyacinth, etc., become frost-hardy to some degree without being subjected to low temperature, when they mature sufficiently, and then they can be hardened further when they are subjected to low temperature. On the other hand, the bulbs and tubers of gladiolus, freesia and anemone are neither frost-hardy nor able to increase their frost-hardiness even if they would be subjected to 0°C. The ability to undergo effective hardening by artificial chilling is closely associated with the degree of their frost. hardiness (Table 2).
2. The minimum temperatures at which the bulbs and tubers are able to survive after 24 hours of freezing in winter are as follows:
Lilium dauricum (Ezosukashi) Muscari (-15°_??_-18°C)>Ornithogalum (-12°_??_-13°C)>Narcissus poeticus (-10°_??_-12°C)>Tulip (var. Mozart) Crocus (var. Large Yellow) (-10°C)>Lilium speciosum (var. rubrum), Nar-cissus, Iris hollandica, Hyacinth, (var. King Alfred), Ixia (-7°_??_-8°C)>Montbretia Antholyza (-5°C)>Anemone, Gladiolus colvillei, Freesia (-3°_??_-4°C)
3. Dried tubers (water content below 25%) of anemone and ranunculus were immersed in liquid nitrogen (-196°C) for 24 hours. After having been warmed, they were planted in moist sand in green-house to test whether they were able to grow. The buds were put forth from the bulbs so treated and grew normally (Fig. 1). From this fact, it seemed that the easily freezable water in cells of these bulbs have been lost by desiccation, and that the bulbs in this state were not injured even when exposed to the extremely low temperature. On the other hand, when the bulbs had adsorbed water sufficiently, they were damaged by freezing even at -5°C. Accordingly, without intracellular freezing, the degree of cold does not seem to exert any important effect upon the bulb, and also it seems that the low temperature itself cannot be a primary factor of damage by freezing.

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I. Forcing test
1. 21-24g. bulbs of William Pitt variety, produced by supplying different amounts of nitrogen, phosphate and potassium fertilizers, as mentioned in the previous report, were selected. The bulbs were treated at 10-15°C. for 30 days starting on July 20th, then at 0-3°C. for 50 days, and were immediately planted in wooden boxes in the plastic film house. The growing conditions for all bulbs were the same. The growth and blooming responses of the tulips were examined.
2. It was observed that the greater the amount of each of the 3 elements supplied to the previous generation, the sooner the blooming and the smaller the rate of blind in the forcing culture. The tendency was observed especially with nitrogen fertilizer, but the effects were smaller with potassium fertilizer.
3 The earliness of blooming and the smallness of rate of blind were highly correlated with the earliness of flower bud differentiation in the seed bulbs.
4. The characteristics concerning with the quality of cut flowers, such as plant height, leaf area, plant weight, flower size, etc. were superior in those tulips that were raised from the bulbs produced by supplying much fertilizers. The after-effects of nitrogen and potassium supply to the previous generation were remarkable in the lower production of the following year.
II. Field culture test
1. In order to clarify the after-effects of fertilizer supply to the previous generation upon the next-generation large (17-19g.) and small bulbs (2.5-3.0g.), which were selected from the plots supplied with different amounts of fertilizers as in the first test, were planted in a field in the usual manner, and the growth, and yield of bulbs were examined.
2. Generally speaking, the tulips produced by parent bulbs to which much fertilizer was supplied were superior in their growth to those produced by parent bulbs given less fertilizer. Especially this after-effect was conspicuous in nitrogen fertili-zer plots, i.e. the less the amount of nitrogen supplied in the previous generation, the later the leaf emer-gence, the slower the plant growth, and the lower the plant height in the next generation.
3. In the large seed bulb plots, the yield of bulbs, i.e. the number and the weight of bulbs, was varied depending on the amount of nitrogen fertilizer supplied to the previous generation. Within the limit of the present study, as the amount of nitrogen fertilizer supplied to the preceding gener-ation was increased, the following generation ex-hibited higher yield of bulbs. Potassium fertilizer supplied to the preceding generation produced a similar tendency though in _??_ smaller scale. The amount of phosphate fertilizer supplied seemed to be of little effect. In the small seed bulb plots, however, it was hard to recognize such an after-effect of the fertilizer condition in the preceding generation as was seen in the large seed bulb plots mentioned above.
4. The content of dry matter in the harvested bulbs tended to increase where increased amounts of fertilizer were supplied to the preceding genera-tion, but seldom were found correlations between the number of split coat bulbs or the formation of dropper of small bulbs, and the amount of fertilizer supplied to the preceding generation.

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The present study has been conducted to investigate the process of tuberous root formation in dahlia, using a single strain and also var. Tensin (medium decorative).
The results of the investigation are summarized as follows:
1. Seedlings of single strain were planted on June 5 and dug out from June to November at ten-day intervals. As the results of observation, it was ascertained that adventitious roots successively appeared from early June to early August. The diameters of the roots increased from the end of June to November, especially after October, then the adventitious roots developed in the tuberous roots.
The similar facts were observed on the plants cultured from tuber.
The adventitious root and tuberous root have similar anatomical structure, and they are distinguished from the normal fibrous roots.
2. In the second experiment, defoliations were made every ten days from June 21 to September to investigate the influence of reduction of photosynthesis upon the number and development of adventitious roots.
The defoliation in June and July reduced the number of roots, while that after September had little influence on the number of roots and the inhibition of the growth of roots.
The shade treatment in October also reduced the diameters of roots.
3. Experiment 3 was performed to investigate the influence of photoperiod on the growth of roots in dahlia seedlings.
The short day treatment (8-hour photoperiod for 20 or 40 days) reduced the number of roots and increased the diameters of roots, while the plants exposed to the long day condition (24-hour photoperiod) did not differ in number and diameters of roots from the plants grown under the natural day length.
In the plants exposed to 24-hour photoperiod, flower buds were not recognized on August 25, but were observed on September 25.

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