培矮64s／E32产量构成因素和穗部性状的杂种优势及相关分析

以大穗型杂交稻培矮64s/E32及其亲本以及对照组合汕优63为供试材料，对产量构成因素和穗部性状进行了分析。结果表明，该组合二次枝梗数多是形成大穗的基础，其二次枝梗数和每穗总粒数的杂种优势分别为62.74%和48.16%，超亲优势分别为30.06%和32.18%。千粒重、结实率等性状的杂种优势表现不突出，单株穗数等性状的杂种优势则为负值，用着粒密度指数对稻穗及其枝梗的着粒密度进行了分析，培矮64s/E32的穗着粒密度指数为7.40，枝梗着粒密度指数为1.20-1.52，其稻穗基部二次枝梗的着粒密度偏高。对产量构成因素及穗部性状之间的相关分析表明，单穗谷重、穗长、穗着粒密度指数、每穗总粒数、一次枝梗谷粒数和二次枝梗谷粒数这6个性状相互之间均存在极显著的正相关，r值为0.651785-0.994344，而结实率与上述性状的相关性均不显著。

Heterosis and Correlative Analysis of Yield Components and Panicle Characters of Pei-ai64s/E32

Two line hybrid rice Pei ai 64s/E32 is a pioneer cultivar released from the super high yield hybrid rice breeding program in China. This cultivar's super high yield potential is characterized by its big panicle. And the large number of secondary rachis branches is an essential component of the big panicle. Heterosis of the number of secondary rachis branches and total grain number per panicle were 62.74% and 48.16%, and heterobeltiosis were 30.06% and 32.18% respectively. Heterosis of 1,000 grain weight and seed setting rate were relatively insignificant, and that of the number of panicles per plant was negative. The seed setting density index (SSDI) was proposed and used to analyze the seed density of the panicle and the rachis branches. The SSDI of panicle in Pei ai64s/E32 was 7.40, while the SSDI of rachis branches ranged from 1.20 to 1.52. Its seed setting density of the secondary rachis branches at the base of panicles was a little too high. Correlative analysis indicated that all correlations grain weight per panicle, panicle length, SSDI of panicle, total grain number per panicle, total grain number of primary rachis branches, total grain number of secondary rachis branches were significant at 0.01 level, with correlation coefficients ranging from 0.651785 to 0.994344, while the correlation coefficients between the above six characters and seed setting rate were insignificant.