新优63的粒重优势研究

对新优６３等９个籼型杂交稻组合的产量性状分析和１９９１～１９９４年江西省及南方区试资料比较，结果表明：新优６３的单位面积有效穗与生产上一些应用组合无显著差异，单位面积实粒数显著少于部分应用组合，其增产的主要原因是千粒重极显著地高于其他供试组合。进而对新优６３的有效穗、每穗总粒数、每穗实粒数、结实率、千粒重等５个经济性状与产量间进行相关和通径分析，进一步表明：该组合千粒重大是其特殊的增产原因。本文指出：通过重粒型组合的选育可能是突破目前三系籼型杂交晚稻组合产量徘徊的一条有效途径

Study on the Grain Weight Heterosis of Xinyou 63

DMRT analysis on yield and its compoments of Xinyou 63 and eight indica late hybrid rice varieties was made. The results showed that the productive panicles per square meter of Xinyou 63 was not signifi cantly different from that of other commercialized combinations. The filled grains per square meter of Xinyou 63 was the least in the combinations tested. The main reason of yield advantage over popular hybrid combinations was that Xinyou 63 had the greatest 1000-grain weight. Correlation and path analysis on yield and five yield components of Xinyou 63 showed that simple relation coefficients of 1000-grain weight to yield (r=0.9616) and filled grains per panicle to yield (r=0.8207) were both positively significant. The order of the contribution to yield (direct effect) was filled grains per panicle (P 3Y=1.0399) > 1000-grain weight (P 5Y=0.3987) > productive panicles per square meter (P 1Y=0.3864). The final effect of yield components to yield was 1000-grain weight > filled grains per panicle > grains per panicle > productive panicles per square meter > seed setting rate. It could be concluded that Xinyou 63 was the combination of heavy grain type and its heterosis was mainly determined by its heavy grain.