The experiment was carried out in pot culture, using two indica varieties (Mas-24 and Muruga-kayan-302) to determine the effect of shading treatment given during the period of 3 weeks before heading or after heading on sterility in indica rice as a part of“studies on sterility of indica rice”in the Department of Agriculture, Peradeniya, Ceylon 1959.
Results obtained are summerized as follows :
1. Shading treatment given at this stage showed no effect on number of panicles per plant in both varieties.
2. The pre-heading shading caused a remarkable decrease in sterility percentage due to an elemination of excessive number of spikelets, particularly in Mas-24.
3. Post-heading shading caused a remarkable reduction in the carbohydrate production during after heading accompanied with very high sterility.
4. Combined pre-and post-heading shading gave an intermediate percentage of sterility between pre-heading treatment and post-heading treatment because effect of both treatments was was compensated with each other.
The results presented here suggest that high sterility percentage observed in general with some of the indica varieties might be attributable to the nature of the varieties capable of producing so many number of spikelets per panicle for the quantity of carbohydrate to be available.

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1) Under the 3 drying methods of leaf material of lemon-grass, the control (no drying), sun-drying for 3 days, and shade-drying for 5 days, a further study on the title was carried out in 1961 mainly tb clear up the relation between the drying treatment of leaf material and the citral content of oil by use of gas chromatography.
2) Regarding the yield of oil., a result similar to that reported in the previous paper wass recognized; the latter 2 treatments gave a little higher yield of oil as compared with the control.
3) The citral content of oil from the dried leaf material was found to be considerably higher than from the fresh leaf material also in the determination by gas chromatography as in the case by the hydroxylamine method. From this, the increase of citral itself in the oil due to drying of the leaf material was confirmed.

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1. Relating to the size of the seedling for set and their growing condition, a series of investigations was practised in two ways, the one was applying vinyl covering and multching as shelters and the other was non-shelter culture.
In a shelter plot, small sized seedling grow faster and flowered earlier than the bigger sized ones.
The shelter, when seedling are set, influenced more in growth of the plant than the size of the seedling.
Giving the seedling a better circumstance and making them grow smoothly, resulted in accelerating the growth and flowering.
2. An investigation was carried out to learn the relation between the pinch off the seedling in setting time and the growth after that.
By this, we found that the pinch off in setting time checked and delayed the growth and flowering, especially on an open field, it resulted in late flowering and low yield.
The pinch off to the young seedling lowed the flowering height a little, but this was not an effective method for accelerating the flowering.

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1. The chromosome of“hamaomoto”is 2n=22, and this plant is commonly known to propagate itself by the seed, and has such a peculiar property that if its bulbous trunk is cut perpendicularly stocks that have many false trunks may be obtained.
2. As for the mode of germination, the seed first grows a“haisho” (embryo sheath), from the tip of which the first grown root extends. A simple leave also grows on the“haiso”.
3. The seed must not be dried, and had better be sown in fall. If sown in fall the seed on occasion germinates within the year but usually germinates next April. The seed may be preserved and sown in spring. The seed of hamaomoto likes light. Those sown in fall appear to grow better after germination than those sown in spring. The growth depends largely on the year's average mild temperature. If the sun's rays are properly shut out, hamaomoto may grow satisfactorily, not necessarily on seashores. Presumably it rather likes inner land better than seaside.
4. If buried about 30 cm under the soil, hamaomoto can tide over winter outdoors. Although that part on the soil dies, the underground bulf survives and grows leaves and flowers later.

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