籼爪交和粳爪交杂种F1代性状间关系的研究

对229个籼爪交组合、98个粳爪交组合的农艺性状进行了相关分析,对籼爪交和粳爪交组合的单株粒重、结实率进行了通径分析,对籼爪交组合农艺性状和品质性状进行了典型相关分析.籼爪交和粳爪交组合间性状相关性表现不同,独立性强的性状籼爪交组合中为谷长、粳爪交组合中为谷宽,其余性状间表现出复杂的相关关系.籼爪交和粳爪交组合均表现每穗实粒数和单株穗数对单株粒重的直接正效应大;每穗实粒数多、单株穗数多且生育期短或适中是提高籼爪交组合单株粒重的选育方向;粳爪交杂种提高单株产量的育种方向是选育每穗实粒数多并且单株穗数也多的组合,同时要兼顾增加每穗总粒数.每穗实粒数对籼爪交杂种结实率的直接正效应大,籼爪交杂种结实率的提高主要依赖每穗实粒数的增加,而其它性状的选择和改良作用不大.提高粳爪交杂种结实率可从3个方面入手,即选育每穗实粒数较多、每穗总粒数较多、且千粒重较大的组合,但主要是提高每穗实粒数.农艺性状和品质性状间存在典型相关.

Studies on Relationship of Traits in Indica/Javanica and Japonica/Javanica Hybrids in Rice

The correlation analysis of agronomic traits, the path analysis of the agronomic characters to yield per plant and seed set among 229 accessions of indica/javanica (IJv) hybrids and 98 accessions of japonica/javanica (JJv) hybrids in rice, and the canonical correlation analysis between agronomic and grain quality characters among the IJv hybrids were conducted in this paper. The correlations of agronomic traits of IJv and JJv hybrids were different. Grain length of IJv hybrids and grain width of JJv hybrids were less correlated with other agronomic traits, but the others showed complex correlation. There were great direct positive effects of grains per panicle and panicles per plant on yield per plant in IJv and JJv hybrids. Breeding of the hybrids with more grains per panicle, more tillers per plant and short or middle growth duration would increase yield per plant in IJv hybrids. The breeding goals of increasing yield per plant in JJv hybrids were more grains per panicle and panicles per plant as well as more spikelets per panicle. There was a great direct positive effect of grains per panicle on seed set in IJv hybrids. The increase of seed set of IJv hybrids mainly depended on more grains per panicle. It would have three ways to increase the seed set of JJv hybrids, i.e., developing hybrids with more grains per panicle, more spikelets per panicle and higher 1 000-grain weight, but increase of grains per panicle was most important. There was a significant canonical correlation between agronomic and grain quality characters.