Nine genotypes of tea clones, as the stage of individual selection, were used in this studies. Number of leaves per plant, leaf length, variability of leaf length, leaf width and variability of leaf width were measured to calculate the correlation coefficients among these characters. Then the relationships were also shown among these five characters and yield in the year after next. Broad sense heritabilities on a single plant basis for number of leaves, leaf length and leaf width were high (0.67-0.79), but variability of leaf length and variability of leaf width had very low values.
Heritabilities on a mean value of clone, how ever, for variability of leaf length and variability of leaf width were relatively high, so it is clear that the clones had significant differences of variabilites or instabilites in these two characters.
Genetic coefficient of variation for number of leaves was large and the other traits's one were small.
Coefficients total, genetic and environmental correlation among these characters were estimated. Large number of leaves significantly associated with large leaf size, and reversely with small these variabilites. Correlations between leaf length and leaf width, between these two variabilities were also positively high.
The relationships among these five characters and yield in the year were shown by single, partial and multiple corrlation coefficients, this indicated that clones grown under the same environmental conditions could be examined for relative yielding capacity by the number of leaves.

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In the F₁ progenies crossed in 1960, the growth, characters of mature leaves and buds, number of buds, yield of first crop were investigated.
The heritability (values, indexes) of height and width of tea bush were 0.436 and 0.554 respectively. As the lateral growth of the Indian varieties was very poor, it was necessary to select such varieties that had ample lateral growth in order to improve the vigor of Indian progenies.
The heritability (value) of the extent of mature leaf was so high as 0.700 that suitable varieties having corresponding leaf extent of Indian varieties should be utilized in crossing. C 17 was a variety which had a moderate leaf extent for this purpose.
The heritability (value) of number of buds was 0.563 but that of yield of first crop was so low as 0.1562 that it was not easy to get a high yielding variety.
From the results of these tests, the important points to utilize Indian varieties for crossing are (1) vigorous lateral growth of bush, (2) large number of buds, (3) moderate characters of mature leaves and plucked leaves. It is also necessary to get a wide variation in F₁ by large scale crossing combinations.

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The differentiation and developmental process of axillary buds in the tea plants were investigated on summer.
The axillary buds of summer shoots contained four immature leaves (including leaf primodia) at different developmental stages. As soon as summer shoots were pruned, the new leaf primodias differentiated in remained axillary buds. These axillary buds flushed about 20 days after prunning. The primodia of new axillary bud emerged at the axil of the immature leaves.
The relations between the developmental ability of new shoots and the growing positions of axillary buds were investigated. It may be concluded that the immature leaves in axillary buds lose viability, if they rested for a long period.

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The influence of water content in soil on the cold resistance of tea plant was investigated, using young plants grown in pots.
The refractive indices of leaf juice increased according to the lowering of air tempearture and the increased value in refraction was larger when the soil in which the tea plant grew was in a dry state than in a wet state.
When the dry soil was moistened in mid December, the increasing of refraction of juice was checked.
No evident difference in cold injury of the tea plant was observed between dry soil plot and wet soil plot which were placed in a glass-house, but the plant in wet soil showed rather less cold resistance by an artificial freezing test. And there was no difference in injury between both plots in the field.
When the water content in soil was temporarily increasd in the coldest season, the tea plant decreased its cold resistance and this symptom became clear several days after the treatment. From the test of relation between the water content in soil and hardening in regulating low temperature, the tea plant in wet soil checked the increase of refraction of juice, so it was necessary to expose the plant to a lower temperature in order to get as the same hardiness as the plant in dry. soil gained.
In the dry plot, the sprouting of buds was later and the yield of first crop was reduced. From the fact, it was thought that the water content in soil should be considered with the reference to the yield of first crop rather than the cold resistance of tea plant.

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The causal fungus of the tea leaf spot disease has been recognized as Phyllosticta theaefolia HARA since 1920, but the inoculation in field using the fungus has not yet been succeeded. On the other hand, in 1939, KUROSAWA reported the tea scab disease which closely resembled to the leaf spot in symptom and was caused by Sphaceloma theae.
The author has investigated the causal fungus of the tea leaf spot and the difference between these two diseases for several years.
The results are summarized as follows :
1. Sphaceloma sp. was isolated frequently from the tea leaf spot lesions as well as Phyllosticta sp. and the tea brown blight fungus.
2. According to the inoculation experiments using Phyllosticta sp. and Sphacelonza sp. both in the field and in the laboratory, Sphaceloma sp. only showed distinct pathogenicity on the young leaves and shoots, and the symptom was hardly distinguishable from that of naturally infected leaves.
3.The morphological characters of Sphaceloma sp. were as follows : Acervuli develop like hills on the upper and under surfaces of leaves, light greyish brown or colorless and are 20-125X10-25μin size. Conidiophores are one celled and 2.5-17.5μ in length. Conidia develop singly from the tip of conidiophores, elliptical shape, singly celled and having generally two oil spots at the two opposite ends. The size of conidia from cultured fungiis(isolate S-2) is 4.7-7.3×2.3-5μ, mean 5.8-2.8μ. There was no difference between Sphaceloma sp. and S. theae. KUROSAWA in the morphological characters.
4. Because of the leaf spot disease was quite identical in symptom and causal fungus with Kurosawa's scab disease, the author concluded that the leaf spot was synonymous with the scab.

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1. Surveys on method of cultivations, climatic conditions, soil conditions and nutritive conditions of tea plant were carried out on more than twenty "Benihomare" tea gardens, which had various severities of the die-back and canker disease, to find out factors affecting the occurrence of the disease since 1960 to 1962.
Factors which seemed to be associated closely with the disease were as follows.
2. From the results of the survey on method of cultivations, the tea gardens which had ill-draining soil, started plucking in too young plant and severely infected with such diseases as Japanese Exobasidium blight (Exobasidium reticulatum) and brown blight (Guignardia camelliae) etc. seemed to be suffered severely from the die-back and canker disease. No disease was seen in tea bushes of less than 5 years old. All severely infected tea bushes were more than 10 years old.
3. Winter temperature during 1953 to 1955 was considerably lower than average and low temperature and much rainfall in summer time were recorded in 1955, on the other side, there were many observations that the occurrence of the disease initiated in these three years.
Severe climatic conditions were also supposed to closely related to the outbreak of the disease.
4. Through the survey on soil conditions, it was found that the disease was severe in such tea gardens which had small air phase or large liquid phase.
These results coincided with the previously stated fact that the disease was severe in illdraining gardens. Root systems of severely infected tea bush also were poor or omnipresent near soil surface.
5. Results of the chemical analysis of leaves collected from many "Benihomare" tea gardens showed that the total nitrogen was rich and P₂O₅, K₂O etc. were poor in severely infected tea gardens.
Judging from the view point of water balance, also, "Benihomare" was presumed to have some specific nature comparing with other varieties of tea plant.

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1. Artificial culture of the ambrosia fungi.
Xyleborus germanus and X. compactus fungi develop mycellia very actively but produce spore very poorly in artificial culture media, in which fresh wood containing medium proved, better. However, when the female beetles bore into the artificial media with ambrosia fungi, the spore formation is observed along the way of galleries, it is, therefore, clearly suggested that the spore formation is promoted by the component of saliva or unknown secreted substances of the beetles. The larvae feed on myceilium as well as spore.
With potato agar media in a test tube, the fungi grow better in plate culture than in slant culture. The optimum temperatures of the fungi development are about 23°C. in X. germanus and about 26°C. in X. compactus.
2. Artificial rearing of ambrosia beetles.
X. germanus can be reared in the artificial culture throughout whole generation of the beetles.
Fresh tea roots (1-1.5cm. in diameter) are cut 2-3 cm. in length and about 100g. of the material are put in 300 ml. Erlenmyer flasks, the flasks are stoppered with cotton plugs and are steam-sterilized in an autoclave. After sterilization, pieces of isolated fungi are inoculated aseptically into the flask and incubated at 23°C. for about 10 days.
When the mycellium of fungus covers the culture medium, 2-3 adult female beetles are introduced into the flask without sterilization. In the flask, ambrosia fungus grows vigorously and can suppress the development of all extraneous fungi, so that the beetles can be reared throughout 1-2 generations in the laboratory.
The female beetles immediately make new galleries and the spore of fungus is formed in the root. Ten or twelve days after invasion, eggs are laid and 2-3 days thereafter larvae are hatched out. The development of the beetles can be observed from outside of the flask.
X. eompactus can not be reared similarly to X. germanus as described above.
3. Biological observation of Xyleborus germanus.
In neighbouring Makinohara tea plantation (200 m. high above the sea level), X. germanus occurs 2 times a year and overwinters in roots forming colony of several broods at adult female stage.
The optimum temperature range of rearing is 21-23°C. and over 25°C. a majority of beetles is dead in the laboratory culture.
The first generation period occurs from June to July and the population increases at maximum rate. The second generation period occurs in September, from July to August the beetles spend in adult female stage and the population is lowest throughout the year.
The adult female beetles prefer to bore into tea roots (1-1.5 cm. in diameter) at about 30 cm. depth under ground and sometimes into tea twigs.
A female lays about 30 eggs, at one time 10 eggs on the wall of ambrosia fungus. It takes 30-49 days at the controlled temperature of 23°C. from the entry of a female to the emergence of the successive adult female.
4. Biological observation of Xyleborus compactus.
X. compactus occurs 2 times a year and overwinters in twigs at adult female stage.
The first generation occurs from July toAugust and the second from August to September.
Surroundings of attacked parts in living stems become brownish discolored and cause "die-back".
The female beetles prefer to bore into slender branches (5-8 mm. in diameter) under the bush surface, but in a high population, they bore into big trunks contacted on the ground level.
The optimum temperature range of rearing in the laboratory is 25-27°C.
A female lays 12-15 eggs in a gallery and it takes 25-27 days from the entry of a female to the emergence of the successive adult female.

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The morphological, physical and chemical characteristics of the tea soils of Miwa district in Shizuoka-Shi were surveyed.
The result of survey was generally summarized as follows:
1. Miwa tea gardens mainly distribute in lowlands, highland and plateau and the tea soils of this district were classified into ten groups by the difference of morphological characteristics of profile.
Among these groups, the tea soils belong to the I-V groups mainly distribute in lowlands, black-brown medium or heavy soils having rich gravels.
The tea soils belong to the VI-VIII groups distribute in highland and yellow-brown heavy soils having a considerable quantity of gravel.
The tea soils belong to the IX group distribute in plateau and black-brown heavy soil having much quantity of humus and porous friable layers.
The tea soils belong to the X group distribute in lowlands and was particular soils having a muck soil in the underlayer.
The physical properties of the surface soils in these groups were comparatively suitable for tea plantation.
2. Among the chemical properties, acidity of these tea soil was as low value as 3 or 4 of pH (H₂0) and the amount of exchangeable bases was mostly 1-3 me. and degrees of base-saturation and calcium-saturation were mostly below 30%.
Cation exchange capacity of these tea soils was generally low and that of the tea soils in lowlands was mostly below 15 me., however, that of the tea soils in highland and plateau was as much as 20 me.
The organic matter content of surface soils in every type of tea soils was generally high, namely, showed 2-10% as humus and that of the humic tea soils in plateau was as high as 10-20%.
The available phosphorus content was generally much in the surface soil and showed as much as 20-40mg. and the absorption quotient of phosphorus was mostly below 1000, but that of the humic tea soils in plateau was as high as 2000.
The content of soluble aluminum in every type of tea soils was generally much.
3. Furthermore, the relation between calcium content of tea soils and pH value, and the absorption of ammonium by these tea soils were examined.
The relation between calcium content and pH value was different with the kind of tea soils, namely, in sandy soils, pH value hastily increased with the addition of calcium, but in clayey soils, its degree slowly increased.
The order of absorption of ammonium salt by these tea soils was amm. phosphate>arnm. carbonate>amm. sulphate and the absorbed quantity of ammonium from these ammonium salts was lower in sandy tea soils than in the clayey tea soils.

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The effects of temperature and flowing velocity of air on the qualities of tea were studied with a primary heating and rolling machine.
Temperature measuring : The temperature of air was measured at six points, the 1st-5th point were in the chest of the machine and the 6th point was outside of it near the fan (Fig. 1). The temperature at the 6th point has been used as a measure for controlling the process.
Temperature differences were observed among the measuring points, especially the 6th point was about 15°C. cooler than other five inner points.
Influences of heat source and velocity of air current : The qualities of tea produced with electric heating of 17, 19, or 24 kw. and with air flow of 2.5, 3.0, or 3.5 meters per second were tested.
Significant differences were found on the qualities of products at the level of heat source but not found at that of air current.
Material temperature : The material temperature during the process was chiefly affected by the air velocity and slightly by the air temperature. The qualities of product seemed to be closely correlated with the material temperature and the data in this experiment showed the tea having good qualities was produced when the material temperature was kept at 40-45°C. through the process.

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A quantitative determination of amino scids and amides (glutamic acid, aspartic acid, alanine, serine, theanine and glutamine) in tea was investigated by paper partition chromatography.
The method was as follows : Treat the hot water extract of tea with basic lead acetate. After removed the excess Pb with H₂S, evaporate the solution to small volume under reduced pressure. Remove the caffeine with chloroform, and separate the neutral, the acidic and the basic amino acid fractions on ion exchange resin columns (Amberlite IRC-50 ; Amberlite IR-120 ; Amberlite IR-4B) by a routine method.
Subject an aliquot of solution to paper chromatography. Chromatograph by two dimensional ascending method on 23x19 cm. of Whatman No. 1 filter paper using phenol water (3 : 1 ) and butanol-acetic acid-water (4 : 1 : 2). After drying the paper, treat the amino compounds on the paper with ninhydrin acetone solution in an electric oven at 60°C, and spray M/25 phosphate buffer solution (pH 7) at the same temperature for 40 minutes. Cut out the spots. on the paper and put them in test tubes. Elute the coloured products with 2.5 ml. of M/25 phosphate buffer solution (pH 7). Cover the test tubes with aluminum caps and heat them in a boiling water bath for 5 minutes. Cool, add 2.5 ml. of 9500 ethanol. After standing half an hour, mesure the absorbancy of coloured solutions at 570 mu with a spectrophotometer.
The coefficients of variation of this method were 1.75-14.3% in the range of 5-30ug. of each amino acid and the recoveries of added amino acids were 92.2-102.2%.

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