[in Japanese]

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1 Branching habit of major tea cultivars at the 2nd year of planting was investigated in southern Kyushu.
2 Materials and methods were as follows.
1) The place of the experiment and plot design were the same with the previous report.
2) The items of investigation and the methods
(1) Number of main branches at the 1st year of planting.
(2) Number of 1st and 2nd branches in the basal position (0-20cm height) of each plant, at the following 4 seasons.
a) The 1st autumn after planting
b) The 1st crop season in the next year after planting (only new shoots, which had 3-6 leaves except banjhi shoot, were investigated.)
c) The 2nd crop season in the next year after planting (only good shoots, which length were over 8cm, were inv-estigated.)
d) The 2nd autumn after planting (only good hardend shoots, which length were over 12cm, were investigated.)
(3) Following characters related with plant form and shooting type in the 2nd autumn after planting.
a) Height (of plant), Spread (of plant), and the ratio, Spread/Height)
b) Height of the most wide spread part (of plant) and the ratio, Height of the most wide spread part/Plant height
c) Inclination angle of longest 1st branch.
d) The ratio, Length of lateral shoots/Length of apical shoot (Max. length of the 1st branch/plant height)
3) Analysis
Obtained data were analysed by analysis of variance (F-test).
3 The results are summarized as follows.
1) The number of main branches of each 1 year old plant of 5 varieties in Trial 1 ranged from 1.3 to 1.7, but no varietal difference was observed. On the other hand, 6 out of 9 variteties in Trial 2 had no branch, and the other following varieties had a few branches ; Okumidori(1.1), Sayamakaori (1.2) and Yabukita (1.3).
2) Number of 1st branch of 1 and 2 years old plants changed as follows.
(1) Trial 1 ; No significant varietal differences were recognized in the number of shoots in the 1st autumn atrer planting. And from spring to autumn in the next year, the number of 1st branch of Kanayamidori and Toyoka was more than that of Yabukita. On the contrary, the number of 1st branch of Asatsuyu decreased after the 2nd crop.
(2) Trial 2 ; only Sayamakaori increased its 1st branches remarkably compared with other varieties of 1 and 2 years old plants in every season. And significant varietal differences were recognized in the number of 1st branch between all varieties with 99.9% confidence.
After the 2nd crop, the number of 1st branches of Okumidori was more than that of Yabukita, the varietal differences were significant with 95% confidence. On the contrary, each number of 1st branch of following varieties was less than that of Yabukita ; Sayamamidori (after tea season of 2nd
crop of 2 years old plants), and Yamakai, Goko, Asahi, Komakage etc. (in the 1st autumn after planting and in tea season of 2nd crop in next year after planting).
(3) Only in tea season of 2nd crop in next year after planting, the number of 1st branch was counted in the upper part (10-20cm height) and the lower part(0-10cm height). Through this investigation it was clarified that there were significant differences in the number of 1st branch between the upper part and the lower part, and in interaction between the varieties and the parts of branching.
The number of 2nd branch of each 1 and 2 year old plant were very few (0-3) in all varieties.
(4) The authors investigated various characters related with plant form and shooting type in the 2nd autumn after planting. And we could clarified the following characters of major varieties based on the results of these investigations including the findings on the number of 1st branch and degree of growth (reported Part 1).
1) Kanayamidori ; Spread type, the most wide spread in lower position, and well grown shoots. Therefore, spread of plant and growth vigor were superior to those of other varieties tested.

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Young stem segments of mature tea plant 'Yabukita' were cultured aseptically on MURASHIGE & SKOOG's agar medium modified by various additives, to determine the suitable medium composition for differentiation of adventitious buds. And also, varietal differences of differentiation of the adventitious bud were investigated.
1) Among the four kinds of auxins tested, adventitious buds was differentiated only with the addition of indoleacetic acid (IAA 0.01-1.0mg/l).
2) To increase differentiation rates of the adventitious bud, IAA was. applied combining with benzyladenine(BA), kinetin or gibberellin A₃(GA₃) each at various concentrations. Differentiation of the adventitious bud was observed only with the combination of GA₃. The differentiation rates of adventitious bud in combination of IAA (0.01-1.0mg/l) plus GA₃ (1.0-5.0mg/l) were higher than that of IAA alone. Whereas the combination of IAA plus BA or kinetin did not induce the adventitious bud.
3) When a few amino acids or organic nutrients such as yeast extract or casein hydrolysate was added to IAA (0.01, 1.0mg/l) plus GA₃(5.0mg/l), differentiation of the adventitious buds were observed only in the combination with amino acids, however their rates were lower than that of IAA plus GA₃ without amino acids.
4) Histological observation of adventitious buds showed that the buds differentiated only from the small lumps of callus developing on the cutting surface. In case of longitudinal slices of ordinary cross sections, cut surface area were enlarged and the differentiation rates of adventitious bud increased to 21.2% compared with that of the cross sections, 7.6%.
5) In the stem segment culture, the differentiation of adventitious buds were occurred in green tea cultivars 'Makinoharawase, Surugawase, Yabukita, Samidori, Okuhikari, Okumidori, Okuyutaka', while the varieties for black tea or oolong tea did not differentiate the adventitious bud.

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Effects of twice skiffings after plucking of 1st and 2nd crop on shoot growth and quality of the following crops were investigated.
1) The earlier the 1st skiffing after plucking of 1st or 2nd crop was than usual, the earlier the times of next crop's bud opening and optimum plucking were.
2) The yield of next crop was sometimesreduced by 2nd skiffing, but rates of overmeature leaves and hard stems, sucker shoots in plucked shoots were reduced.
3) The earlier the time of optimum plucking was, the better not only the appearance but also the quality of liquor of made tea was. The quality of liquor of the best crude tea by twice skiffings was better than those of the once skiffing which were sifted by a sieve of No.7 (screen's aperture is at one-seventh of about 3cms spaces) or an optical tea stalk separator.
4) From the results of these experiments, it was considered that not only the balances of length or maturity of shoots but also the quality of liquor were improved by 1st skiffing, which was done earlier than usual.
5) To improve qualities of 2nd or 3rd crop of crude tea, appropriate times of twice skiffings were concluded as follows. For the second crop, the 1st skiffing was between 2 and 5 days after plucking of 1st crop, and the 2nd skiffing was between 17 and 22 days after plucking. For the 3rd crop, the 1st skiffing was between 2 and 5 days after plucking of 2nd crop, and the 2nd was about 16 days after that.

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The feasibility of near infrared spectroscopic analysis (NIR) was examined in its application to the determination of neutral detergent fiber (NDR) in green tea as an index for maturity and quality of the green tea.
1) An experiment using a NIR instrument (mode 6250, Pacific Scientific) showed that absorbance values for unground samples of tea leaves dried after steaming were higher than those for ground ones over the wavelength range of 1100 to 2500 nm. There was a tendency that the absorbance increased as a NDF content in the sample decreased.
2) The best calibration for NDF which was composed of three wavelengths of 1818, 2330, and 2152 nm was obtained by a stepwise multiple linear regressin analysis of the second-derivative using 82 calibration samples and subsequent prediction using 82 predication samples, In the prediction test, this calibration demonstrated a high correlation coefficient (r=0.921) and a low evaluation index (E.I.=18.12) betweemn the chemical values for NDF and NIR values. These results indicate that NIR method has a high capability to determine the NDF in unground tea, which is a im-portant parameter in relation to maturity of the tea leaves.
3) By employing the ground samples of the same meterials, the similar procedure yielded the best calibration. This calibration is composed of four wavelength of 2270, 1276 2368 and 2314 mn, in which 2270 nm has been reported to be assigned to cellulose. The correlation coefficient r and evalution index (E.I.) for the prediction samples were 0.942 and 15.49, respectively, in this case. These results are superior to those for non-ground samples. There is no significant difference in the mean difference between the both values.
4) It was found that the E.I. values and the correlation coefficent for these two NDF calibra tions were inferior to those for a calibration of total nitrogen in green tea reported so far. Nevetheless the present study indicates that the NIR analysis has a potential to determine NDF accurately and precisely in green tea.

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