The morphological characteristics of roots of cold-resistant cultivars, 'Sayamakaori' and 'Komakage', were investigated in the 2nd year after planting (December, 1988). 'Yabukita' and 'Okumidori' were used as the standard and the reference cultivars, respectively.
The results are summarized as follows.
1)'Sayamakaori' was significantly superior in the weight of lignified roots in 0-20 cm depth to the other 3 cultivars.
2)'Komakage' was significantly superior in slender-root weight in 60-70 cm depth to the other 3 cultivars. In general, roots of 'Komakage' were long, and the longest root was about 1 m long.
3)The root characteristics of the 2 cultivars mentioned above seem to be favorable to cold-resistance.

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1 The growth of shoots of main tea cultivars was investigated after the 1st pruning in the 3rd year after planting in southern Kyushu.
2 The materials and the methods used in this experiment were as follows.
(1) Place and plot design
These were the same as in the previous paper (Part I).
(2) Investigated items and methods
1) After the 1st pruning at the end of March 1989, the following 4 items were observed on the pruned surface ; spread of plants, number of branches of each plant, number of branches in a 20 cm square on the pruned surface and cross-sectional diameters of branches and their variation.
2) After the 1st pruning the number of shoots was counted at the following 3 times ; middle of May (Number of new shoots was counted), beginning of July (Number of the 2nd pruning was counted), and beginning of September.
3) At the beginning of September, only good shoots (over 15 cm lenght) were investigated on the following 2 items ; total number of shoots of each plant, and partial numbers of shoots in 3 parts of each plant (lower part : 0-15 cm height, middle part : 15-20 cm height, upper par : 20-25 cm height).
4) At the end of October, the growth of plants was investigated on the following 2 items ; height of plants and spread of plants>
3 The results are summarized as follows.
(1) Observations on the pruned surface at the end of March.
1) Spread of plants. Test 1 ; The spreads of 'Yutakamidori' and 'Kanayamidori' were larger than those of the other 3 cultivars, and significant varietal differences were recognized between them with 99.0-99.9% confidence. On the contrary, the spread of 'Asatsuyu' was the smallest of all.
Test 2 ; The spread of 'Sayamakaori' was larger than those of the other 8 cultivars (with 99.0- 99.9% confidence), while the spreads of 'Samidori', 'Komakage' and 'Asahi' etc. were smaller than those of the other cultivars.
2) Number of branches of each plant.
Tes 1 ; Only the number of branches of 'Kanayamidori' was larger than those of the other 4 cultivars, and significant varietal differences were recognized between them with 99.0-99.9% confidence, while the value of 'Asatsuyu' was small as a whole.
Test 2 ; The numbers of branches of 'Yabukita', 'Okumidori' and 'Sayamakaori' etc. were large comparatively, and no significant varietal differences were recognized between them. On the contrary, the values of 'Komakage' and 'Samidori' were smaller than those of the other cultivars, and significant varietal differences were recognized between them.
3) Correlation between the number of branches of each plants and the number of branches to a 20 cm square.
A significant coefficient correlation (r=0.97-0.99) was recognized between the number of branches of each plant and the number of branches to a 20 cm square.
4) Cross-sectional diameters of pruned branches and their variation.
Test 1 ; The cross-sectional diameters of pruned branches of 'Yutakamidori' were larger than those of the other 4 cultivars, "and significant varietal differences were recognized between them with 99.0-99.9% confidence. On the contrary, the values of 'Asatsuyu' were smaller than those of 'Toyoka' and 'Yabukita' with 95% confidence.
Test 2 ; Only 'Sayamakaori', of which cross-sectional diameters of pruned branches were larger than those of all other cultivars (with 99.9% confidence), while the values of 'Goko' and 'Ujihikari' were small as a whole.
Cofficients of variation in 'Yutakamidori' and 'Asatsuyu' which showed the largest and the smallest values in Test 1 respectively, were less than those of the other 3 cultivars.
(2) Changes of number of shoots from the middle of May to the beginning of September.
Test 1 ; The numbers of shoots of all cultivars increased from the beginning of July to the beginning of September. The value of 'Kanayamidori' was the largest of all, while that of 'Asatsuyu'was the smallest throuthout the period.

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The possibility of long term storage of tea germplasm was examined.
Tea pollen could be stored at a very low temperature of -80°C with a high germinability rate for a period of 12 years after collection in 1976. Pollen stored at -80°C for 12 years showed as high percentage of fruit set as the fresh pollen when the stored pollen had been used for crossing. Tea seeds were stored under three different conditions : first, at 5°C for 0 to 9 years, second, at -80°C for 2 days, and third, in 13 kinds of organic solvents for 19 days in room temperature. Tea seeds stored at a low temperature could be preserved for more than 9 years in good condition if they were placed in sealed polyethylene bags at 5°C.
In the experiment of storage for 2 days at a very low temperature of -80°C, a part of the seeds in which the water content was reduced to 10-13% before storage remained alive and was able to germinate.
The results showed that tea seeds can be stored at an very low temperature for a long period of time in future.
When tea seeds were stored in 13 organic solvents for 19 days, there was no germination except for hexane and cyclohexane. Tea seeds stored in organic solvents showed a relatively high germination rate of 92.9 for hexane and 66.7 for cyclohexane. However, since the germination rate was very low after storage in hexane and cyclohexane for a period of one month, it was concluded that tea seeds could not be stored for a long period of time in organic solvents.

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Two cultivars ('Sayamakaori' and 'Yamatomidori') planted in rows (1.3 m×50 cm) in the field were covered with a clean saran screen (#300) before the flowering time in early September and grown in tunnel-shaped isolation cages.
Artificially reared flower fly (Eristalis cerealis FABURICIUS) was used as a pollinator. The pupa which was at just before emergence was put into each cage at the number of 0 (control), 100, 200 and 400. As the size of each cage was about 13 m² (2.6 m × 5 m), the density was 0, 7.5, 15 and 30 pupae per m², respectively. The date of the first release was October 5 and thereafter the pupae were supplied three times every 2 weeks.
The emergence rates of the flies ranged from 75.3 to 98.8 % of pupae.
It was found that the flower flies were useful for cross breeding of tea, because they actively visitted flowers and pollinated effectively in the isolation cages. Fruit set percentage and the number of seeds obtained increased with the increase of the number of pupae within the range of 400 for each time of release.
A high percentage of fruit set was obtained with 15 to 30 pupae per m² in each cage when they were released 4 times.
It was estimated that the rate of self-fertility of the tea cultivars was 0.5 % for 'Sayamakaori' and 5 to 7% for 'Yamatomidori'.

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