The varietal test of upland rice was carried out in Lampung Province, Indonesia, using thirteen traditional local and five improved varieties. The results obtained were as follows.
1. The traditional local varieties were generally taller than the improved varieties, but the former produced generally fewer tillers than the latter. Most traditional local varieties had a flag leaf that was relatively long and broad, and also they had long, well-exserted panicles which made them well suited for ani-ani harvesting.
2. Bicol, ar improved variety, was a typical short-statured and high tillering type, with relatively short panicles, and the other improved varieties were rather similar to the traditional local varieties because of their relatively longer panicles and greater plant height as compared with Bicol.
3. The growth duration of improved varieties was generally shorter than that of traditional local varieties. The former ranged from 103 to 119 days, while the latter ranged from 119 to 140 days.
4. Most varieties, except for Bicol, were susceptible to lodging at maturity. Sheath blight and bacterial blight disease were observed both in the traditional local and improved varieties, but rice blast disease was found only in Bicol.
5. Bicol was the highest yielder, with about 3.3 tons of unhulled rice per hectare. The yields for the other varieties ranged from 1.4 tons to 2.7 tons per hectare; about 2 tons per hectare seemed to be the mean yields.
6. The shape of unhulled rice was examined in twelve varieties. Most varieties were of a slender type, although Si Rendah and Cempoturi were of round type and large type, respectively.
7. In order to demonstrate more clearly the characteristics of each variety, principle component analysis was carried out using fifteen criteria. Varietal differences between the improved and traditional local varieties, and also those among the traditional local varieties are clearly shown in the scatter diagram of eighteen varieties in Figs. 3 and 4.
8. The problems of introducing new improved varieties to traditional upland areas were discussed especially in relation to cultivation conditions and cropping systems.

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[in Japanese]

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Using three floating rice varieties from Bangladesh, Thailand and Vietnam, effects of some environmental factors on the position of the lowest elongated internode (LEI) were examined.
The position of LEI went down one to two internodes under both short day and shading conditions, while the position went up one to two internodes under high temperature, 35°C, compared to outdoor conditions. On the other hand, position of LEI was affected little by plant age at the beginning of submergence and by submerging depth.
The above results suggest that the position of LEI in floating rice may be one of the fairly stable morphological characters affected only by short day, shading and high temperature.

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The indices suitable for expressing the growth rate accurately without regard to the growing stage of a lateral branch of castor plants were considered.
A constant value, k, calculated from the equation presented was shown to be suitable for expressing the growth rate constantly during growth and for comparing growth rates among plants which received different treatments.
The author proposed to name the constant, k, the“growth rate coefficient”and use it to express the growth rate of branches. In order to calculate the growth rate coefficient accurately, the number of days must be counted from a very early stage which is tentatively assumed. The calculating methods are shown in the text.
It was shown that the coefficient does not show a constant value, but shows a maximum or minimum value at a certain point of time, according to whether growth has been inhibited or promoted respectively.

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