黄淮麦区小麦产量和生理性状的遗传增益研究

Genetic Gain for Grain Yield and Its Relational Traits in Yellow-Huai River Valley Winter Wheat Region

研究品种更替过程中产量及其相关性状的变化规律对培育高产品种具有重要指导意义。利用1980—2005年间河南省育成的8个推广面积较大的品种为研究材料，于2010—2011年和201l～2012年问连续2年种植，分析了近25年河南主栽品种的产量变化趋势。研究结果表明，供试材料的产量和产量相关性状显著受环境和基因型及基因型与环境的影响。1980—2005年间河南小麦产量年遗传增益为63kg,／hm^2，千粒重和收获指数显著改良，其中，千粒重年遗传增益为0．42g，收获指数年遗传增益为0．29。株高随品种的选育年份呈显著降低趋势，平均每年降低株高0．42cm。而单位面积（m。）穗数、穗粒数和生物学产量均无显著变化。说明近25年来河南小麦产量的提高主要通过提高粒重来完成，今后再通过降秆来提高收获指数已不再现实，应在进一步提高产量的同时适当放宽株高限制，提高茎秆质量的同时。加强改良新品种的收获指数。

Knowledge of the changes in grain yield and its associated traits is essential for understanding the main yield-limiting factors and validating future breeding strategies in the Yellow and Huai River Valley Winter Wheat Region. The objective of this study was to analyze the improvement in grain yield and its associated traits in winter wheat （ Triticum aestivum L. ）. Eight genotypes represented the significant advances in wheat production in Henan province from 1980 to 2005 ,were selected to examine in the field experiments at Luoyang for two years in 2010 -2012. Results showed that all yield relational traits were significantly affected by cultivar,season, and their interaction effects. The genetic gain in grain yield was 63 kg/hm^2 a year, the improvement of kernels weight and harvest index （ HI ） was significant. In addition, the genetic gain in thousand kernels weight and harvest index were 0.42 g and 0.29, respectively. Plant height was significantly reduced with the released years, generally was O. 42 cm a year. The change of Spikes per square meter, kernels per spike and above-ground biomass were not significant with released years. The results suggested that genetic gains in grain yield in Henan province were mainly contributed by increases in kernels weight and harvest index, which could achieved through improving the source for grain filling. It is really no longer appropriate to improve the harvest index by reducing plant height in the future. So, breeder should extend appropriately in plant height, and improve the quality of stem strengthen and harvest index.