The experiments were carried out from 1967 to 1969 in Malaysia and in 1971 in Japan with the idential conditions and samples as the previous report. The solar radiation was calculated by the modified Budyko's formula. The results are summarized as follows:
1. In the individual plant, the total and daily transpiration increased particularly in the local long term varieties (Table 1) . This was a different trend to the plant population. Thus the transpiration was governed by the combined factors of plant growth and climatic conditions.
2. In the individual plant, the daily dry matter production of the new varieties was larger than that of local long term varieties, though that of IR 8 was not always large (Tables 1 and 2) . In the plant population, the total dry matter production was proportional to the length of growth duration until 140 days after transplanting (Fig. 1) . The panicle weight (yield) was the maximum at about 110 days of the growth duration, because panicle/straw ratio decreased in accordance with the advance of growth duration.
Although the total dry matter production of the new varieties was not large, the daily dry matter production of Bahagia was nearly equal to that of IR 8 and larger than that of Radio Ebos 33, and as to the daily grain production IR 8 was nearly the same as Bahagia and larger than R. Ebos 33 (Fig. 1 and table 3) . In short, though in the individual plant productivity IR 8 and Hoyoku, the varieties of good plant type, was not high as compared with the local varieties, the productivity of plant population of IR 8 was evidently high.
3. In the tropical plant population, according to the calculation based on water requirement, the efficiency of solar energy conversion was 1.4% (1.1-1.6%) for photosynthesis, on the presumption that about 40% of net assimilation was consumed by respiration, and was 0.9% (0.7-1.0%) for dry matter production (Table 3) . The efficiency was particularly lower in the local varieties as compared with that of the temperate rice.
The efficiency of solar energy utilization for evapo-transpiration was about 70% in average.

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Some physical properties was determined on each horizon of soils under planted pepper, soils under primeval forest cover and soils after the burning of the forest, all of which are distributed in two regions in Amazon, one in the surronding of Belém (Castanhal and Santa Izabel) and another in Tome-Açu colonies (first and second colonies) .
The result obtained are summarized as follows :
1) The index value measured by soil hardness tester ranged from 7 to 34 mm in surface soils and from 16 to 35 mm in subsoils (B horizon), respectively. The values are especially high in the soil of Tome-Açu area.
2) Bulk density are generally high. However, there are no essential difference between the different areas.
3) In the surrounding of Belém, as years passed after the soils were cultivated for pepper, both the hardness and bulk density increased clearly.

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When the Japanese mulberry form Ichinose was cultivated in the greenhouse and not exposed to the low temperature during winter, the dormancy could not terminate and the sprouting of buds in the next year was delayed extremely. Even when some of the buds sprouted, the portion was limited to the apical part of the shoot. This fact leads to the possibility that this mulberry form would enter into dormancy if cultivated in tropical regions in South East Asia.
The mulberry thus in a dormant condition could be induced to sprout by the middle-cutting and by gibberellin spraying in summer. Also the sprouting of the mulberry, cultivated in the greenhouse and in a state of dormancy, was more difficult when the means of cutting the shoot at its base in spring, leaving 2-3 buds, was used than when the middle-cut in summer was used. In this case gibberellin treatment seemed to be effective for stimulation of bud sprouting.

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Castor plants of Shanghai local variety of small grain were grown in field at Komaba in 1973. The growth of branches and leaves was measured and compared with that of potted plants in greenhouse.
The growth in length of main stem, branches and leaves was proceeded linearly to number of days except the later stage, when it was expressed logarithmically, as in the case of potted plants in greenhouse. The regression coefficient (b) of regression equation log₁₀Y=bx+c (Y: length, x: number of days after germination) was used as the index of growth rate in length of a stem and a leaf.
The growth rate in length and increasing rate of plastochron index (P. I.) in secondary branches were greater than those in primary, tertiary and quarternary branches. However, there was no difference among different order branches from primary to quarternary in P. I. or from primary to tertiary in growth rate, when the effect of temperature during the growth was eliminated by means of their regressions to the mean air temperatures. The growth rates of quarternary branches were lower than those of other order branches.
As to the growth rate and P. I. increasing rate of a stem, no difference was observed between the 1st node and 2nd node branch in primary and secondary branches, but the 2nd node branches were greater than the 1st node branches in tertiary and quarternary branches. It was generally found that under inferior growing conditions the growth rate and P. I. increasing rate were smaller in higher order branches and lower node branches than lower order branches and higher node branches, respectively. The inhibition of growth of a branch was observed as the shortening of linear growth period under slightly bad conditions, and as the decrease in growth rate in the early stage of growth under severer conditions. In the castor plants grown in pot in greenhouse, decrease in growth rate and P. I. increasing rate took place at lower order branches than in field. The growth rates and P. I. increasing rates in potted plants were smaller than those in field.
No difference was observed among the positions (node number in ascending order) of leaves in lower order branches as to the growth rate of leaves. In higher order branches, however, the leaves at higher node had smaller growth rate than lower leaves. The growth rate of a leaf of potted plants in greenhouse was smaller than that of plants in field.
The branches orf a same order started growing simultaneously with the difference of only about a day as to the stage of 5 mm or 10 mm length even among the branches on different mother stems. The 1st leaf atained 10 mm long at almost the same time as 10 mm stage of the branch on which the leaf arose.
The growth rate of a branch was 0.1184 at 26°C and 0.4231 at 30°C on the average. The number of leaves appeared to increase at the rate of a leaf per about 70°C in sum of everyday's mean air temperature in the range from 20 to 30°C. These values are useful for estimation of the growth of branches in field.
It was observed that the first flowering time of the raceme of a stem coincided with the time when whose P. I. was calculated to be (n+1) in greenhouse (n is number of leaves of the stem) . Since the first flowering time of a stem coincides with the 10 mm long stage of the lateral branches arising on the stem, the number of days from the beginning of growth of a branch to that of the next order branch can be roughly estimated from the number of leaves, P. I. increasing rate and the temperature during the growth of the former branch.

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[in Japanese]

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