[in Japanese]

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Investigation of the wild tea plant distributed in the central Taiwan revealed that there are two types of tea growing in the hilly district and in the mountain district, and their differences were elucidated by comparing both kinds morphologically.
In the properties of plants tea plants growing in Mt. Meiyuan are of tree-type and those growing in Yuchin are of shrub-type. In the characteristics of leaves of tea plants in Mt. Meiyuan have larger length and width and larger number of veins than those in Yuchin. The leaf shape (length/width) of tea plants in Mt. Meiyuan is narrow oblong and the leaf apex is acuminate.
The leaf shape of those in Yuchin is roundish and the leaf apex is cuspidate. The mesophyll of tea plants in Mt. Meiyuan is thinner and softer than that of tea plants in Yuchin. With respect to the presence of hair the terminal bud of both species has hair and the discrimination in the terminal bud between both species is difficult, however, while young leaves of the species of Mt. Meiyuan have no hair, some of those of the species of Yuchin have hair, and others have no hair. Accordingly the nature of young leaves of the species of Yuchin has much variations.
In view of properties of plants and characteristics of leaves the tea plant of Mt. Meiyuan is similar to var. assamica and it is interesting from the standpoint of the distribution of tea plants in Asia. It will hereafter be necessary to elucidate the morphological variability in tea plants from Assam, in India, which is the habitat of the tea plant, to Taiwan.

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By using the breeding materials of the Assam hybrid with or without wind quard, cold resistance in winter was investigated.
Cold resistance, annual correlation coefficient of cold resistance and correlation between cold resistance and cold hardiness were vary with the method of cultivation management. Comparing cold resistance of the hybrids in the same combination, the hybrids without wind quard were suffered from more severe cold damage. It would be said that cold damage was promoted by exposure to wind. In the case of cultivation without wind quard, it was not easy to get the hybrids suffered lightly even though the various varieties were crossed with the Assam varieties.
Heritability value of cold resistance was fairly high. Cold resistance of the Assam varieties was very weak, so it was necessary to combine with the cold resistant varieties in order to get the resistant hybrid, but it was very difficult to breed the bearable hybrid for low temperature in 1967, and almost hybrids were needed protection against cold.
It would rather breed the hybrids introduced good quality of the Assam variety than breed the cold resistant hybrids in utilizing the Assam variety for crossing.

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Ammonium sulphate is recommended as a nitrogen fertilizer for pineapple cultivation, but it is not so clear why ammonium sulphate is the best among the nitrogen fertilizers.
In order to clarify this reason the relation between the characteristics of ammonium sulphate and the growth of pineapple plants was examined in sand culture under glass.
1. Growth of pineapple seedlings was more promoted in the following ascending order; Ammonium sulphate, Urea, Ammonium phosphate.
Thiourea led seedlings to wither soon after the start of this experiment.
2. Effect of form of nitrogen supplied on the growth of seedlings showed that the most favorable combination of NH₄-N and NO₃-N for growth was 0: 10 among the solution with the same total nitrogen content.
The more NH₄-N ratio increased, the more the growth was promoted, and the more NO₃-N ratio increased the more the growth was stunted.
3. The behavior of seedling in sand culture of carrying the hydrogen-ion concentration showed that acidic pH promoted the growth in contrast with the arrested growth under neutral or alkali pH.
4. Addition of sulphur powder to culture medium promoted to some extent the growth,
5. The foregoing results seem to induce the conclusion that the characteristics of ammonium sulphate is favorable for pineapple plant growth.

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[in Japanese]

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Cacao fruits growing in electrically heated green house were investigated. About twenty cacao fruits (pods) were yieldeJ annually. In green house, cacao trees produce flowers and fruits continually all the year round under suitable conditions, but many fruits fall in early stage. Main pollination season in green house was from October to December, main harvest season, from April ro June. In pollination season, monthly average air temperature was about 27°C. Yielded pods were smaller and cacao beans were lighter than usual. But we got fairly well many cacao beans.

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