水稻杂种后代籽粒直链淀粉含量选择与品质和产量性状的关系

 选用4个稻米直链淀粉含量有显著差异的粳稻品种配制两个杂交组合（系选1号×通769和东农423×藤系180），研究其杂交后代籽粒直链淀粉含量选择对品质和产量性状的影响。结果表明，籽粒直链淀粉含量选择对杂种后代蒸煮食味品质和产量相关性状有不同程度的影响，其影响程度因杂交组合及性状不同而异；在蒸煮食味品质性状中，淀粉黏滞性谱的崩解值和消减值受直链淀粉含量选择的影响较大，而在产量相关性状中抽穗期、单株有效穗数、结实率、单株粒重等受直链淀粉含量选择的影响相对较大；通过直链淀粉含量的连续定向选择可以从杂种后代中分出直链淀粉含量不同的后代，粳稻杂种后代低直链淀粉含量的定向选择效果优于高直链淀粉含量的选择效果，更容易得到超低亲的变异类型；直链淀粉含量的选择对杂种后代产量性状的影响较复杂，存在有利或不利的影响，低直链淀粉含量的选择将会导致单株粒重的下降。

Relation of Amylose Content Selection with Quality and Yield Traits of Cross Progenies in Rice

Influence of amylose content selection in cross progenies of rice during breeding on quality and yield traits was studied using two crosses derived from four japonica rice varieties with significantly different amylose contents (Xixuan 1×Tong 769 and Dongnong 423×Foukei 180). The results showed that the effects of the amylose content selection on cooking and eating quality properties and yield traits in cross progenies varied with crosses and traits. Breakdown viscosity, setback viscosity, number of productive panicles per plant, seed setting rate and grain weight per plant were all affected largely by the amylose content selection. Progenies with different amylose contents could be separated and selected through successive directional selection for amylose content. The directional selection effect for low amylose content was better than that for high amylose content in cross progenies of japonica rice and the lines with low amylose content below their low parent value could be obtained easily. It was observed that the effects of the amylose content selection were complex, being advantageous or disadvantageous to yield related traits of cross progenies. Selection for low amylose content during breeding would result in descending in grain weight per plant.