Variarions in Degree of Chalkiness of Rice Kernels According to Their Positions on Panicle

광잎 심복백의 수상위치에 따른 변이

This trial was conducted to find out some tendencies in variations of grain chalkiness according to their position on a panicle. To know the varietal character in variations of chalkiness and their relations with grain weight, distribution of chalkiness in bulk seed was observed for four varieties. Milyang 23, relatively clear variety and SR601-25-1, much chalky variety were checked for the grain chalkiness in their positions on the panicle. The results obtained are summerized as follows: Rice chalkinss were varied in degree from 0 (clear) to 9 (chalky) within a variety. Large number of grains were distributed to clear for clear variety and to chalky for chalky variety, but almost equal number of grains were distributed to all degree of chalkiness for intermediate chalky variety. For the relationship between degree of chalkiness and grain weight, chalky grains founded in clear variety and clear grains founded in chalky variety decreased in weight, while in intermediate chalky varieties both grains of clear and chalky decreased. There were great varietions in grain chalkiness on a panicle for both clear and chalky varieties. There was no definite trend in distribution of chalkiness except that the first primary branch and terminal grains in every primary branch showed clear in Milyang 23. Mean degree of grain chalkiness was relatively high in grains of middle part of panicle only from Milyang 23.

미입의 심복백정도가 수상위치에 따라 어떻게 달라지는가를 구명하기 위하여 심복백정도가 상이한 4가지 품종에서 우선 미입별 심복백정도의 분포와 이들의 입중과의 관계를 보았고 다음으로 심복백이 적은 밀양2003와 많은 SR 601-25-1에 대하여 심복백의 수상분포를 조사한 결과는 다음과 같았다. 1. 품종내에서 미입의 심복백은 투명입(0)에서 부터 심복백입(9)에 이르기까지 다양하게 분포하였는데 투명입중은 투명입이, 심복백입종은 심복백입이 가장 많았고 중간입종은 전 등급에 고르게 분포하였다. 2. 심복백정도와 입중과의 관계에서 투명입종은 심복백잎이, 심복백립종은 투명입이 가벼웠으며 중간입종은 투명입과 심복백입이 다 가벼웠다. 3. 미입 심복백의 수상분포에서 투명입종은 이삭의 끝 부분인 제1지편과 각 지편의 미단입들이 모두 투명하였고 기타 부위에서는 일정한 경향이 없었다. 4. 지편의 평균심복백 정도는 투명입종에 속하는 밀양2003에서만 중간부입의 지편이 약간 높은 편이었다.