In Fuji district, Shizuoka Prefecture, known for its production of Fuji-Wase cabbage, rice is grown in summer under paddy field conditions and is followed by cabbages, which are, as winter crops, sown in July and September, transplanted following rice and harvested throughout winter and in April respectively.
Onion and barley are also grown as winter crops, and the growth of onion planted the year following cabbage with a rice crop in summer has been recognized to be inferior to that of the control, that is, onion following barley or onion itself. This phenomenon seems to be peculiar in this district and prevents onion production to extend.
The data presented here have been obtained from investigations carried out in 1953 and 1954 and may be summarized as follows.
1. Onion following cabbage grows very poorly throughout winter, and this poor growth is most strikingly accentuated in March and April, resulting in 30 to 70% reduction of yield in comparison with the control crop. Neither disease nor deficiency symptom, however, can be found to occur particulary following cabbage.
2. Total N content of the top of onion following cabbage is lower in the early stage, comes up to the same level with that of the control in April and later is kept higher till harvest, while that of the control plants attains the highest value in April and then decreases.
P and K contents are considerably lower following cabbage and the differences from those of the control are most remarkable in April and especially in P content, which can be little restored till harvest. Ca and Mg contents are also lower following cabbage in early stage of the growth and restored later to almost the same levels with those of the control.
In the contents of these nutrient elements in the bulb, however, no consistent differences can be recognized.
3. The soils of this district are inclined to be acid in general and especially following cabbage the soil is conspicuously acid perhaps because of heavy manuring of ammonium sulfate fertilizer for cabbage crop without liming. Thus following cabbage, pH is lower, Daikuhara acidity y_??_ is larger and exchangeable Ca content is lower than following barley or onion, while there can be found no consistent nor remarkable differences in exchangeable Mg and K contents and in available P extracted by 1/5 N HCl or 2/1000 N H₂SO₄ (pH 3.0). Moreover, it is observed that the growth of onion following cabbage is as satisfactory as that of the control when two soils do not differ in pH.
4. Amount of ammonium sulfate fertilizer for cabbage crop is at least 1500 lbs. per acre and in some cases as much as 3000 lbs. per acre is used without liming, while P and K are not fertilized sufficiently.
For onion crop N is also overfertilized and P and K fertilization seems to be appropriate except that all amount of P fertilizer and compost are topdressed a month after transplanting instead of basic application.
5. Increased application of P fertilizer, superphosphate, as basic manure increases the yield of onion regardless with the preceding crops and liming immediately befor onion transplanting is not effective in general, except in the case acidity is especially strong following cabbage.
6. It may be concluded from these results that the inferior growth and reduced yield of onion following cabbage are due to the stronger acidity of the soil following cabbage together with the failure of P absorption or nutrition resulting from it.

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1. For the sake of the scientific and practical importance, in an attempt to learn about the effects of the nitrogen nutrition on the sex expression of the cucumber plant as influcnced by different levels of nitrogen application and soil moisture supply, ex-periments were conducted by means of sand culture with the following cultural solution:
Salts Concentration
NH₄NO₃ 172.5mg/l N: 80ppm
KH₂PO₄ 181.9 P: 40
KCl 15.3 K:60.2
MgSO₄.7 H₂O 245.9
Ca(NO₃)₂ 117.2
FeCl₃ 6H₂O trace
MnCl₂.4H₂O trace
2. The seedlings were raised under the varied day length and night temperature. Short day and low night temperature favor the pistillate flower formation. Under the short day and low night tem-perature, the effects of the differential nitrogen supply and watering on the female flower differen-tiation are masked. Under the long day and high night temperature, the female flower differentiation, being arrested by the day length and night temperature, further influenced by the nitrogen supply and watering. Abundant nitrogen supply arrests the female flower formation, especially in case of the restricted watering.
3. Soil moisture with moderate nitrogen level favor the plant growth. More abundant the mois-ture supply, more luxuriant is the plant growth. Under the low soil moisture condition, plant growth is arrested indifferent with the amount of the nitrogen supply.
4. The first female flower differentiates on the lower node with more abundant water supply and less nitrogen application. It seems that the number of nodes preceding the first female flower is reduced with the lower nitrogen level in plant.
5. Femal flowers successively differentiate seem-ingly accompanied by the restricted plant growth, under the differential nitrogen and moisture supply. The luxuriant growth is followed by the more nu-merous, staminate flower nodes preceding the ap-pearance of the succeeding female flower nodes.
6. Nitrogen percentage of the whole plant varies in accordance with the amount of the nitrogen app-lication. With more abundant moisture supply, in-vigorating the more luxuriant growth, the nitrogen percentage of the plant lowers regardless of being supplied even with the same amount of nitrogen by the cultural solution.
7. As above stated, lower nitrogen percentage is followed by the reduction of the number of nodes preceding the first female flower, and on the other hand, the luxuriant growth is followed by more numerous staminate flower nodes, hence it may be advisable for the practical grower to maintain mo-derate nitrogen supply and watering in the nursery, especiallg under the unfavorable day length and night temperature for the early pistillate flower differentiation.

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Experiments were carried out to clarify the influ-ences of the forms of nitrogen supplied with vary-ing concentrations on the growth, yields and chemical compositions of turnip in sand culture under glass. In the first experiment, mixed nitrates (KNO₃: Ca (NO₃)₂, ; Mg(NO₃)₂=5:5:4), NaNO₃, NH₂NO₃, (NH₄)₂SO₄ and (NH₂)₂ CO were used as nitrogen sources and nitrogen concentrations supplied were 5, 10, 20, 40, 80 and 120 m. e. for each nitrogen source, respectively. In the second experiment, nitrogen sources were NaNO₃, NH₄NO₃ and (NH₄)₂SO₄, and nitrogen concentrations supplied were 1, 3, 5, 10, 20, 40, 60, 80 and 120m. e. All known nutrients were provided for each treatment. Results of both experiments were summarized as follows.
(1) In the mixed nitrates and NaNO₃ treatments, leaves were light green and even-surfaced. On the contrary NH₄NO₃ plants produced deep green foliage, and with increased nitrogen concentration their leaves became darker green and uneven-surfaced. Further, in the later stage of growth, they developed symptoms similar to that of potassium deficiency. In the (NH₄)2SO₄ series, leaves were darker green at the lower concentrations, but at the higher concen-trations became dull to yellow green and developed injuries due to excessive ammoniacal nitrogen. Leaves of the (NH₂)₂CO plants were chlorotic.
And leaf color was proportional to the chlorophyll contents in the leaves.
(2) Among mixed nitrates, NaNO₃ and NH₄NO₃ treatments, there was no great difference of their top growth up to 40m. e. (560ppm) nitrogen level. But beyond 40m. e., the decreasing of growth was most remarkable in the NH4NO3, and least in the mixed nitrates. The growth of plants supplied with (NH₂)₂CO, especially with (NH₄)₂SO₄ were markedly inferior to the above 3 nitrogen forms at every concentration. And at higher concentrations of (NH₄)₂SO₄ and of NH₄NO₂, the decreasing of fleshy root growth was more remarkable than other nitro-gen forms, and their fibrous roots were also injured.
(3) Total nitrogen content of both leaves and roots increased with increment of nitrogen supplied, irrespective of nitrogen forms. And in the higher nitrogen concentrations supplied (beyond 40m. e.), increment of nitrogen content was remarkable for (NH₄)₂SO₄ and NH₄NO₃ treatments, but gradual for mixed nitrates and NaNO₃. (NH₂)₂CO plants at lower concentrations contained less nitrogen than other nitrogen forms, but at higher concentrati-ons absorbed fairly much nitrogen. And generally NaNO₃ plants accumulated much of nitrate nitro-gen, but (NH₄)₂SO₄ plants contained only trace, and NH4NO3 was intermediate. As to ammonium nitrogen, the relation of (NH₄)₂S0₄>NH₄NO₃>NaNO₃ was found, but accumulation of ammonium nitrogen was much less compared with nitrate nitrogen.
(4) In the NH₄NO₃, especially in the (NH₄)₂SO₄ treatment, phosphorus content of leaves was higher and increased with increment of ammoniacal nitrogen supplied. As to potassium, plants supplied with mix-ed nitrates or (NH₂)₂CO contained much. Plants supplied with NaNO₃, NH₄NO₃ or (NH₄)₂SO₄, had less potassium than the above 2 nitrogen forms, and potassium content decreased against increased Na or NH₄ supply

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Several storage experiments of vegetable seeds have been carried out since 1950. One year storage was made in 1950, 51 and 56. Two series of long storage experiments were started in 1950 and 55 respectively. Experiments on the resistivity of seeds to heat was carried out in 1953_??_55.
1. At any relative humidity of the atmosphere, moisture contents of seeds were highest in bean, pea and soyabean, lowest in peanut and cucumber, and medium in spinach, onion, carrot, cabbage, etc.
2. Pea and bean produced hard seeds when their moisture contents failed below seven percent.
3. One year storage in 1950 and 51 was carried out in room temperature in desiccators which were conditioned to the relative humidities of 30_??_90 percent by saturated salt solutions. Same seeds were stored in paper bags, tin cans (no desiccant), tin cans (containing quicklime) and desiccators (contain-ing calcium chloride). Long period storage was carried out in paper bags, desiccators (no desiccant) and desiccators (containing calcium chloride) placed in room temperature, and desiccators (containing calcium chloride) and paper bags placed in a coldr oom of 0°C. These short and long storage experi-ments have shown that seeds of turnip, chinese cabbage, mustard, cucumber, watermelon, squash, tomato and radish belong to the type of longer life span, and those of carrot, edible burdock, welsh onion, onion, spinach, cabbage, lettuce, pea and bean belong to that of shorter life span.
4. In the long period storage, seeds stored in tin cans containing quicklime had shorter life spans than those in desiccators containing calcium chloride. This is due to the extremely small moisture con-tents of seeds of quicklime plot. Extreme reduc-tion of moisture contents of seeds is harmful to embryos. Seeds of quicklime plot and calcium chlo-ride plot had moisture contents of 2.4_??_4.1 percent and 5.4_??_9.3 percent respectively. The harmful ef-fect was significant especially in bean and pea seeds. In one year storage, however, the effect was hardly observed.
5. In cold room storage (0°C), several kinds of seeds lowered their germinability to some extent after two years. This is due to the large moisture contents of seeds of this plot (12.1_??_18.4 percent). This experiment has shown that cold storage in 0°C is less effective than room temperature storage in dry atmosphere.
6. Experiments on the resistivity of seeds to heat was carried out as follows: One to three grams of seeds conditioned to given moistures con-tents were put into 15cc test tubes. These tubes were sealed tightly and placed in the thermostat conditioned to temperature of 60 or 50°C. Onion and welsh onion seeds were tested also in 70° and 80°C. After certain periods the germinalility of these seeds was examined. Results have shown that re-sistivity of seeds to heat is generally in proportion to their longevity, that is, heat resistivity is great in chines, cabbage, eggplant, cucumber and shung-iku (chrysanthemum coronarium), small in onion, welsh onion, spinach and edible burdock, and me-dium in cabbage and carrot.

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The investigations were carried out on the flo-wer-bud formation of 40 varieties of turnip, sown in fall, 1954, and in spring, 1956. The results obtained are summarized as follows.
1. The symptom of flower-bud formation was ob-served 40_??_63 days after sowing in spring planting, and 45_??_66 days after in fall planting, in most of the Japanese varieties of turnip, but in Kokabu and other varieties, which were regarded as Western European group, it took considerably longer time to reach the stage of flower-bud formation than in the Japanese varieties.
2. There was a striking difference in the num-hers of days from planting to flower-bud formation between the Japanese varieties and Kokabu or the Western European group, though there were minor-differences among the Japanese varieties.
3. The authors had classified the turnip varieties, grown in Japan into three group from the view point of morphological characteristics: (1) Japanese: group, (2) Western European group, (3) Intermedi-ate group.
Those grouping may be adaptable to the classifi-cation of varieties in relation to the earliness of flower-bud formation to some extent.

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1. Ether extracts of the disk part and the in-ternal bud portion of onion bulbs during the ordi-nary sprouting period have been chromatographed separately and the chromatograms assayed using Avena coleoptile elongation method. In the inter-nal bud of onion bulb treated with MH, both grow-th promoting and inhibiting substances were found alike as those found in the untreated material. Si-milar tendency was also detected in the etiolated gram seedling.
2. Respiratory intensity of onions treated with MH did not show any difference from the con-trol throughout the rest period, but when the con-trol bulbs began to sprout and the rate of its respi-ration rose, the increase of respiration was sup-pressed in the disk part of treated bulbs to some extent and the decline of respiratory quotient was found at the same time.
3. Though the sprouting and the elongation of gram seeds were greatly inhibited when they were treated with MH, O₂ uptake in the stem re-maind unaffected during a considerable period after the treatment. However, the respiratory quotient in the growth region of stems of the treated mate-rial was always lower than the control.
4. The experimental results with onion bulbs and gram seeds received MH treatment indicated that the growth inhibition must have been induced from the disturbance of respiratory mechanism, not the fluctuation of growth substances.

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1. In order to obtain the basic data for seed pro-duction in slow bolting spinach (var. King of Den-mark), the author studied the flowering behavior on varying planting date and the influence of ver-nalization on the photoperiodic response of spinach under varying daylength. Unvernalized spinach seeds were sown in soil of clay pots placed in greenhouse on the 20th each month. The plants grown from seeds which were treated with vernali-zation temperature of 2±1°C, for periods of 0, 1, 2 and 4 weeks, were exposed to daylength of 8, 10_??_14 (natural daylength in autumn or spring) and 24 hours (supplemented with artificial illumi-nation).
2. Seed vernalized at 2±1°C, resulted in plants which initiated flower buds or open flowers sooner, or at higher percentages, at all photoperiods above 8-hours in greenhouse. The longer the chilling peri-od or daylength, the greater the acceleration of flowering.
3. The reproductive development of unvernalized plants grown under continuous light was accelerat-ed to the same degree as those exposed cold tempe-ratures. From these facts, it will be assumed that the both factors, the chilling of seeds and continu-ous illuminations, may have been acting to flower induction of spinach to the same degree.
4. The after effects of vernalization treatment may alter the photoperiodic responses of this crop, and the critical photoperiod necessary to flowering in this variety was found to be beneath 13 to 8 hours, as a result of vernalization.
5. The possibilities in seed production of King of Denmark planted in autumn (from Sept. to Nov.) seemed very little due to abnormal flowering and fruiting induced from older stocks.

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This experiment was carried out to know the effect of maleic hvdrazide on bolting of spinach plants.
The seeds of “Ujo” variety were planted in the field and WAGNER's pots, in November, 1954, and March, 1955. About 10ml each of maleic hydrazide solution was sprayed on the leaves and buds of spinach plants a week before their bolting, from April to May in 1955. The concentrations of the sprayed solution were 0.10, 0.25, 0.30 and 0.50 percent in the field, and 0.05, 0.10, 0.25 and 0.30 percent on the potted plants. The experimental results revealed that the most effective concentration of maleic hydrazide for bolting control was 0.25 percent in the field and 0. 10 percent on the potted plants. But their effect had lasted only for short period, seven to ten days. If the second spray was applied, the leaves or stems were dwarfed, turned yellow, and at last died after thirty days of spraying.

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In the previous paper, the authors reported that the high temperature treatment of the bulbs was effective for increasing the yield of new bulbs, and the effectiveness depended on the date and length of the treatment, or the degree of injury in the flower bud by the treatment. In this study, the authors carried out two experiments to clarify the relation between the degree of injury in the flower bud and the subsequent growth and yield of new bulbs.
In the first experiment, the bulbs of Bartigon variety were treated at 33°C for 8, 12, 16, 18, 20 or 23 days from Oct. 7. In the second experiment, bulbs of City of Haarlem variety were treated at 33°C, for 24 days from Sept. 15, for 17 days from Sept. 30, or for 8 days from Oct. 17. A few bulbs had been taken out at intervals during the treat-ment, and the grade of injury in the flower buds by the treatment was examined.
The degrees of injury in the flower bud were, classified into the following five grades.
0: no injury.
1: the tips of the petals were slightly softened.
2: about one third of the petals was softened and membranous, and stamens started to be softened.
3: about a half of the petals was membranous, and the stamens were perfectly softened.
4: petals turned to be perfectly membranous, and both stamens and pistil were softened.
Young leaves and flower stem were not injured, even if the flower bud was perfectly softened. But they were likely to be softened when the bulbs were treated so drastically as the flower bud turned brown.
The highest yield of new bulbs was obtained, when the effect of the treatment was high enough the degree of injury in the flower bud was advanced to the 2 or 3 grade.
From the practical stand point, it is suggested that grade of injury in the bulb may be exactly deter-mined by examining a few bulbs at intervals until the proper grade is attained.

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1. The present studies were carried out to investi-gate the heredity of the occurrence of pithy tissue, and that what correlation would be seen between its occurrence and the other physiological characters shown in the descendants of varietal hybrids in radish.
2. When the growth of 20 F₁ hybrids crossed among 7 varieties, differing in easiness of the occur-rence of pithy tissue, was examined, it was found that the characteristic of the parents were fairly conspicuously inherited to F₁, in such characters as eaf number, leaf weight, root weight, T/R ratio, concentration of soluble matter in root sap, size of xylem parenchyma cell of root, content of starch in root, etc. In these cases, the greater part of the F₁ combinations surpassed the average of parents in many characters, but in comparing with the parents which retained heavier root weight, the F₁ combinations superior to the parents were not so many.
3. Such a definite tendency as the F₁ is much easier or harder of the occurrence of pithy tissue than the parent varieties, could not be found, and in any combination the F₁ showed the resembling average value of the parents on its occurrence, and the influence of the vigor of hybrid on the occurrence of pithy tissue was not recognized.
4. The occurrence of pithy tissue in varieties of F₁ and their parents was highly correlated with the concentration of soluble matter in root and size of xylem parenchyma cell of root, and slightly with content of starch in root, but there could not be found distinct correlation with root weight and T/R ratio. Those results indicate the possibility of breeding such lines as resistant to the occurrence of pithy tissue regardless early growth or rapid growth of corpulency of the root. For this purpose it must be suitable to use as the parents such va-rieties as “Eichin” and “Tokinashi” of which the capacity of assimilation of the top is great and the roots become fully replete.
5. In the individual investigation of the growth of the F₂ which were produced from 3 combinations, in which the “Eichin” was crossed with other va-rieties differring in easiness of the occurrence of pithy tissue, a remarkable segregation of all cha-racters has been observed in every combination. The occurrence of pithy tissue of the individual F₂ was correlated with concentration of soluble matter, size of xylem parenchyma cell, and content of starch in root, but had no relation to the root weight or T/R ratio with one exception, as in F₁ generation.
6. These facts reconfirmed the author's consider-ations, as it was described in the last report, that the occurrence of pithy tissue may be ascribed to, the abrupt corpulency which does not catch up the-fullness of roots, and also that its occurrence in F₁ and F₂ was highly correlated with the physiological-characters shown in the previous reports, even when the inheritance was utterly disturbed and genes were recombined by means of the varietal crossing as in this investigation.
7. The inheritance of the occurrence of pithy-tissue may not be due to the existence of special-factors which directly determine its occurrence, but rather it may be indirectly inherited to the-descendants in accompany with the inheritance of many other characters such as responsible to pro-voke the unbalanced growth of the root corpulency, . as mentioned above.
8. In breeding of resistant varieties to the occur-rence of pithy tissue, it is necessary to select the. resistant individuals from the young mother plants as accurately as possible as in case of selecting the-ones in their maturing stage. As an effective method to achieve this purpose it is suggested that selection of the individuals which contain high percentage of soluble matter

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