Throughout the second and third plucking seasons in 1955, the growth of shoot, yield of leaves, qualities of tea, and amount of chemical constituents in the leaves were surveyed, using three green tea. varieties (Yabukita, Miyoshi, Natsumidori, and Tamamidori) and one black tea variety (Benihomare).
The relation between the maturity of leaves, which was indicated by the ratio of bhanji leaves and called in Japanese as Debirakido %, and the above-mentiored observed data was investigated and it was proved that the best plucking time could not be decided after the.leaves had exceeded over 90% of Debiraki in every tea variety.

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In the performance of seed-propagation, it is desirable that the percentage of self-fruiting is high. This percentage varied from 0.2 to 4.2%, and the avera e was 2.2% for the last five years, so it was assumed that the tea plant is almost self-unfruitfulness. In order to study the cause of this phenomenon, the authors attempted to investigate the mechanism of self-fertilization and try to find the artificial method effective to get self-fertilized seeds.
From the studies of the behaviour of the fruit drops and the growth rate of embryo sac, it was cleared that the rate of fruit drops was remarkably different, between self and cross pollinated flowers and the droppings of the self pollinated fruits were mainly due to the non-fertilization.
The cause of low self-fruiting was thought to be due to the low degree of self-compatibility. This mechanism was presumed as follows. Although the development of pollen tubes in style was slow as well as the percentage of pollen germination on stigma, main cause was the remarkable retardation of bollen tubes at the tissues between the base of style and the upper part of ovary.
With the aim of artificially promoting the self-fertilization, we tried the bud pollination, the old flower pollination, the spraying of 10^-4% Fruitone solution and the pollination at the close of flowering time. In the case of the former three methods, the development of pollen tubes in style was promoted as well as the germination in stigma, but this promotion could not yet surpass the retardation of tube growth between the base of style and the upper part of ovary, so the effect of these treatments on fertilization was not marked.

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To test the practical applicability of the rapid tannin., test with potassium bichromate, the correlation between the tannin content and the reaction of the tea leaves to potassium bichromate was examined.
No correlation was obtained, so this method is not applicable to the tannin test of the tea leaves.

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Gas dispersion of cyanide fumigation in the sheet covered on the tea bushes was tested with calcid duster or pot method.
1. The best result was obtained when two rows of bushes were covered with a double vinyl sheet(white and black)and the insecticide was scattered by a duster from either end between the rows.
2. The pot method proved that the gas dispersion, decreasing rate of gas density were better than the duster fumigation but the operation was somewhat troublesome.

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1. Fifty-eighty p. p. m. of parathion was contained in dried tea leaves plucked on the day of spraying. But it was decomposed very rapidly on the tea leaves and most of which was lost in the course of 3 weeks after spraying.
2. Most of surnicide (ACC 4124) sprayed on the tea leaves was decomposed in the course of 10 days after spraying.

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The photometric determination of chlorophyll. in the fresh tea leaves and made tea was researched.
A high correlation coefficient between the chlorophyll concentration and the optical density of the acetone extract of tea by a red filter was existed, and a regression line of chlorophyll concentration upon the optical density of the extract was obtained.
By this regression line, the variation of the chlorophyll concentration of the samples during. the tea manufacturing process and the storage: was measured.

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[in Japanese]

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The chemical change of ascorbic acid on the black tea manufacture was investigated by the 2, 4-dinitrophenylhydrazine method. The results were as follows : Ascorbic acid was oxidized in the withering process and disappeared when rooling. Dehydroascorbic acid increased in the withering process and decreased in the fermentation process. 2, 3-Diketogulonic acid increased by the rooling and in the fermentation process.
These changes were accelerated by the-heating. The total of them in black tea was less than the initial content in tea leaves. It is, therefore, supposed that ascorbic acid was changed to some substances through dehydro ascorbic acid and 2, 3-diketogulonic acid on the black tea fermentation process.

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The purified two tannin, fractions, which were formed by the oxidation and polymerization of catechins, were isolated from black tea. One fraction contained 1.02% of nitrogen and the other 8.33%.
It is, therefore, supposed that the oxidized quinone-type tannin made a melanoidin pigment as the result of the combination with amino acid and protein and spoiled the quality of black tea.

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In order to study the distribution of caffeine in tea plant, qualitatively the paper chromatographic method and quantitatively the Kjeldahl method were used.
As the results of analyses, it was found that caffeine existed in all organs except timber and root of tea plant.

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The colloidal titration method for the determination of pectin in tea leaves was investigated and the established method was as follows : The leaves washed with methanol was extracted with 0.5% ammonium oxalate at 80°C. and the obtained extract was made acidic or alkaline and individually treated by the pectin decomposing enzyme. The resulting solutions were titrated with the colloidal method. The content of total pectin was estimated from the difference of these two titers. The content of soluble pectin, which was extracted with water at 20-30°C, was known by the same procedur.
The pectin of other plants also could be determined by this method.

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The pectin content of tea leaves was determined. by the colloidal titration method and the following results were obtained.
1. The insoluble pectin did not transformed into soluble pectin (S) on the steaming.
2. In young sprout, the content of total pectin (T) was little and S was much, but in old leaves, T increased and S decreased.
3. On the same season, the content of T increased and S decreased in the lapse of time.
4. In the first plucking season, the content of T was much more than in another seasons but the content of S seemed to be less changed.
5. The content of T in green tea varieties was much more than the one of black tea varieties.
From the above mentioned results, it was found that the younger the leaves, the more the content of T decreased and S/T ratio increased and the pectin number. (S/T²×1000) was, therefore, seemed to bed a good indicator for the quality of tea leaves.

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[in Japanese]

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The carbohydrates in black tea were divided into fourteen fractions. Free sugars and the component sugars of each fraction have been investigated mainly by the method of paper chromatography and the following results were obtained (see Table 2).
Fructose, glucose and arabinose were detected as free monosaccharides, and sucrose, maltose, raffino-e and stachyose as free oligosaccharides.
Inositol.and two kinds of unknown substances as free sugaralchols were also detected.
Rhamnose, glucose, galactose, fructose, xylose and galacturonic acid were detected as the components of glycosides.
Arabinose, galactose, galacturonic acid, rhamnose and glucose were detected as the components of hot 50% ethanol-soluble polysaccharides.
Galactose, galacturonic acid, arabinose, rhamnose, ribose (?), de_oxyribose (?) and glucuronic acid were detected as the components of cold water-soluble polysaccharides, and besides this arabinose, galactose, galacturonic acid, desoxyribose, ribose, glucuronic acid, rhamnose and mannuronic acid as the components of hot water-soluble polysaccharides.
Arabinose, galactose, galacturonic acid and small amounts of glucuronic acid and mannuronic acid were detected as the components of hot 0.5%, ammonium oxalate-soluble polysaccharides.
Xylose, mannose, glucose, ribose, desoxy ribose, galactose and mannuronic acid as the components of hemicellulose, galactose, rhamnose, desoxyribose, xylose and ribose as the β-cellulose, xylose, galactose and rhamnose as the y-cellulose components were detected.
a-Cellulose and a small amount of lignin were also detected.

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It was confirmed, by the application of the cutting method of paper chromatograms, that fructose 0.7%, glucose 0.5%, arabinose 0.4%, sucrose 0, 6%, maltose 0, 5%, raffinose 0.1%, stachyose 0.1%, inositol 0.5% and two unknown sugaralcohol 0.06%, 0.1% existed in free form in black tea (Shizuoka) respectively.

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Translocation and distribution of P³² absorbed from the root of the tea plant cultured in F³² contain'ng medium were investigated.
The result was summarized as follows :
1. The P³² absorbed from the culture medium was first accumulated in the root, then moved upward slowly in the tea plant. The higher the-P³² content of the culture solution and the longer the culturing' period, the more the P³² was accumulated in t e leaf, stem and root.
2. Each part of the tea plant which was applied P32 on the back side of the leaves was richer in F³² content than that applied on the reverse side of the leaves.

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