亚种间杂交稻大穗形成机理初步研究Ⅱ．影响大穗的若干因子分析

A Study on the Mechanism of Large Panicle Formation in Inter-subspecific Hybrid RiceⅡ. Analysis on the factors affecting large panicle formation

本文分析了茎粗，单茎重，叶面积３个因子对亚种间杂交稻赣化７号与品种间杂交稻汕优６３的大穗形成的影响。结果表明：①增加茎粗和单茎重能显著地促进大穗形成，增加上部叶片面积也对大穗形成有利；②赣化７号形成大穗的能力较汕优６３强，且对环境的敏感性较汕优６３弱；③增加物质供应对赣化７号的颖花发育和大穗形成较汕优６３更为重要；④赣化７号增加颖花数主要应促进颖花分化，汕优６３增加颖花数应以促进颖花分化为主。

The effect of three factors, stem perimeter, weight per plant, and leaf area, on the formation of large panicles was analyzed in this paper. The results showed that increase in stem perimeter, weight per plant, and upper leaf area could significantly promote large panicle formation. The large panicle formation of Ganhua 7 was larger in capability, and less sensitive to environment, than that of Shanyou 63. Increase in dry matter supply was more important to spikelet development and large panicle formation in Ganhua 7 than in Shanyou 63. The chief way to increase the number of spikelets was to promote spikelet differentiation in both Ganhua 7 and Shanyou 63 in addition to preventing spike retrogration in Shanyou 63.