Nutritional factors accompanying the development and ripening process of bulbous plants were studied.
A. Hyacinth
1. For the purpose of researching the ripening process of the hyacinth bulbs, “prepared”bulbs were examined together with the normally ripe ed bulbs. The microscopic observation revealed the floral development. The chemical analysis evinced the accumulation of the reserve materials.
2. The flower bud is formed in late June. Although the early dug bulb stored in room temperature formed no flower bud, the prepared bulb, dug on May 26, formed the flower primordia.
3. In the bulb, as the bulb ripens, all the nitrogenous constituents and the carbohydrate material increase. (Table 1. Fig. 8)
4. Under the“preparing”process, the soluble nitrogen fract on markedly increased and the insoluble nitrogen, sugars and polysaccharides decreased. The higher temperature causes the rapid transformation of storage materials to the mobile form and the consumption of the carbohydrate material is accelerated. (Table 1. Fig. 8)
5. The march of the nutritional concentrations on the fresh weight scale as regards the ripening process evinced most remarkably the increase of nitrogen, carbohydrate content showing slight decrease at the third sampling. The preparing process also caused the increase of nitrogen concentration, especially the soluble fraction. (Table 2. Fig.9)
6. Nitrogen accumulation, especially the abundance of soluble nitrogen seems to be of importance in regard to the formation of flowerbud.
B. Gladiolus
1. The transformation of the storage materials of gladiolus corms with march of growth was studied.
2. The flower bud differentiated after forty days growth, when the length of the longest leaf attained about 50cm.
3. The chemical constituents of the gladiolus corms decrease as the bud develops. In the earlier period of its growth, the plant utterly depends upon the nutritional supply from the storage materials of its own corm. The development of the leaves on the young plant, however, soon accompanies assimilation of carbohydrate material.
4. As percentages of fresh weight of corms, nitrogen and carbohydrate constituents except direct reducing sugar and water soluble polysaccharides decrease with march of plant growth. (Table 4. Fig.11)
5. As percentages of fresh weight, all constituents except starch decrease in the leaves. The increase of the total grams of leaves, however, being enormously great, the increase of the total amount of various chemical constituents of leaves is consequently very large. (Table 5, Fig. 13) (Table 3, Fig. 12)
6. In this case the flower bud formation seems to be accompanied by the enough accumulation of nitrogen and carbohydrate material in the leaves after about forty days growth.

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[in Japanese]

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Varieties of Kaki (Diospyros Kaki) are used to be classified into two forms, pollination constant and pollination variant. In the former, the brown dots are never seen in the fruit flesh even in the seeded fruit, but in th latter, the browning of the flesh occurs in proportional intensity to the number of seed developed. The classification is applicable to the astringent as well as the non-astringent varieties. The brown dot is the tannin cell with coagulated and oxidized contents in it. The oxidation of the contents in the tannin cell may be brought about by the activity of oxidizing enzymes. The present study is carried out to accertain the relation of oxidizing enzymes to the browning of fruit flesh on the one hand, and to make oonsiderations of an analogous mechanism of oxidizing enzymes to the colour change of fruit into dull grey after artificial removal of astringency on the other.
The writer tested the peroxidase and oxidase reactions with 24 varieties. The reaction of peroxidase is measured by WILLSTÄETTER'S pyrogallol method, and of oxidase with guaiac tincture.
SZENT GYÖRGYI's hypothesis, which denotes that the peroxidase is in close relation to ascorbic acid in a respiratory system, is taken into account and ascorbic acid (reduced form) is measured by the titration method after TILLMAN's 2.6-dichlorphenol-indophenol with 41 varieties.
Further, the influence of artificial processing to remove the astringency and of the short day treatment on the oxidizing enzymes and ascorbic acid content is studied.
The experimental results are summarized as follows:
1. Ascorbic acid content is higher in the pollination constant than in pollination variant. The contrast is especialy remarkable in the non-astringent varieties. These results indicate that the ascorbic acid is found in the inverse proportion to the occurrence of brown dot.
2. The activity of peroxidase correlates to the density of brown dots, and the most intensitive reaction of peroxidase is represented in the non-astringent pollination variant.
3. The reaction of oxidase is concurrent with that of peroxidase in any case.
4. After the artificial removal of astringency of astringent fruit, ascorbic acid decreases, though the activities of oxidizing enzymes being not influenced.
5. By the short day treatment, ascorbic acid decreases, and the reaction of oxidizing enzymes increases.

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Using the spinach (Japanese variety) as samples, the ascorbic acid contents of the blades, the activation of the enzyme which oxidizes ascorbic acid into dehydroascorbic acid, and the effect of carbon dioxide on the ascorbic acid content of plants were studied from the satndpoint of storage. The amount of ascorbic acid in the blades was determined by the titration method with 2, 6-dichlorphenol-indophenol solutions, described by EMMERIE and FUJITA et al.
The fresh blades, which were just being cut, contained the ascorbicacid in the state of reduced form and the same amount of theascorbic acid was found even in the extracted plant juice. The ascorbic acid oxidase might be absent in the juice, because no reaction of enzyme appeared on synthetic ascorbic acid after adding the juice to it.
The ascorbic acid content of blade tissue was influenced remarkably by the carbon dioxide contained in air in the storage, and the highest content was found in the sample which had been kept in the lowest concentration of carbon dioxide.
The disappearance of reduced ascorbic acid in the storage started rappidly in the contact with carbon dioxide regardless of temperature. After loss of ascorbic acid during storage in the air, which contained much carbon dioxide, there was no complete recovery even if the extract of tissue was treated with hydrogen sulphide for 30minutes

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With respect to root color, the following genes may be assumed:
G: a gene for pale green neck.
C: a gene for flavones as chromogenic substance for the production of anthocyanins.
R: a gene for the production of red pigment.
B: a gene which produces no color alone, but acts in conjunction with R gene to produce purple pigment.
R^s: a gene for red striping.
R^f: a gene causing a red coloration of the vascular bundle in all parts of the plant. In the root this gene manifests red flesh. R^f gene is mutable, reverting to its recessive white(R^f→r).
Red flesh, red striping, red, and white are so related geneticallythat any two of them taken together give results conforming to amonogenic scheme. Consequently it seems probable that the gene forred flesh constitutes a set of multiple allelomorphs with three genesfor red striping, red, and white.
The probable genotype of the root color may be represented as follows:
ccrrBBgg, CCrrBBgg……white (white neck),
CCrrBBGG……white (pale green neck),
CCRRbbgg……red (white neck),
CCRRbbGG……red (pale green neck),
CCR^sR^sBBGG……reddish purple striping (pale green neck),
CCR^fR^fbbGG……red flesh (green neck).

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[in Japanese]

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