Studies on the storage of rice seeds : II. The moisture content, viability, and longevity of rice seeds in different methods of processeing

Abstract

In order to carry out successfully seed raising of a large number of rice varieties it is most important to be equipped with a practical method of processing seeds which would be equally safely and efficiently applicable to any of the varieties dealt with. After studying some different methods of processing rice seeds varying in the stage of maturation since 1958, the authors found out a very useful method so-called "directly dryig method". In that method, safely dried rice seeds of about 7% moisture are prepared for storage in 3 days after harvesting, the time of which may be favorably ranged between 40th and 50th day after heading. Threshing seeds with a thresher of 550 m/min (M) without drying the whole plant on racks after harvesting, and then hot air drying of the seed at 40°C for 3 days (N) immediately after threshing are the most important parts of that method. In the present report, the moisture content, viability, and longevity of rice seeds treated through that method were shown with special comparison with those by other methods. Since that method was applied to seed raising of rice varieties as the genetic stocks a remarkable improvement in its efficiency was brought about in the authors' laboratory.