水稻糯质基因对产量构成性状的影响

Effects of Waxy Gene on Yield Components in Rice (Oryza sativa L.sp.indica)

利用3对糯与非糯近等基因系研究了糯质基因(wx)对产量构成性状的影响。3对糯与非糯品系均仅具有千粒谷重这一产量构成性状有极显著的差异,糯稻比非糯稻降低7.3—9.7%,降低的原因并非由于谷粒体积的减小而是由于糙米粒重和谷粒比重的降低。糯稻与非糯稻具有相同的同化产物库容,但由于灌浆不充实,米粒较小,导致糯稻谷壳内余留较大的空隙。糯稻千粒壳重增加所造成的糙米率降低与谷粒比重下降两者综合作用可能使糯稻的糙米产量降低幅度大于稻谷产量。培育高产糯稻品种应从开源畅流的角度以提高谷粒比重为目标,达到提高千粒谷重和糙米率,增加产量的目的。

Effects of waxy gene on yield components in Oryza sativa L.sp.indica were studiedusing three pairs of waxy and nonwaxy near isogenic lines,Guangluai 4,Yuanfengzao andZhenzhu 19.There were no significant differences between each pair of them except that1000 grain weights were 7.3—9.3% lower in waxy lines than that in nonwaxy ones,which was attributable to smaller kernel size and lower specific gravity of waxy grain.Al-though the potential sink capacity of photosynthate in waxy lines was equal to that innonwaxy ones,waxy grain might be considered inferior to nonwaxy grain in grain filling,which suggested that the gap between the floral glume and kernel of waxy grain was largerthan that of nonwaxy grain.Both lower percentage of brown rice due to their higher 1000hull weight and lower specific gravity of grains in waxy lines might make brown rice yieldmuch lower than expected as grain yield.Increasing the 1000 grain weight and percentageof brown rice should be the major objectives for the development of high yielding waxyrice variaties.