小麦主要性状的遗传相关性及其选择效果研究

对13个小麦品种(系)26个性状的5种遗传参数研究表明,穗数与产量的相关系数很低,且与其他性状呈负相关或微弱正相关,这说明现有品种的单位面积穗数已接近或达到高限;同时,穗数、穗粒数的直接通径系数很高,是产量构成因素中最重要的因素。可见,当前小麦高产育种在保证一定穗数的前提下,要着力于穗粒数的提高,同时要兼顾千粒重,才能实现小麦高产稳产。进行多性状组合选择方能高产,"倒一叶鞘长+穗长+粒重叶比"相对选择效率较高、简单易行,可作为综合选择的较佳指标。

Studies on the Correlation of Genetic and the Effect of Selection in Wheat Main Traits

This paper survey the 26 agronomic characters of the 13 new wheat cultivars(lines).The yield with its agronomic characters of the wheat cultivars(lines)were analyzed by statistics,correlation and path analysis results indicated.1.There were not significant correlation among the number of ears per hectare,grain yield and its agronomic characters.This indicated that the number of ears per hectare close or reach a high threshold.With the path analysis,the direct path coefficient of kernel the number of ears per hectare and the number of kernels per ear were high.This indicated that the number of ears per hectare and the number of kernels per ear were basic factors of yield components.the number of ears per hectare,the number of kernels per ear and 1000-kernels weight should be harmonized to achieve super high and stable yield in breeding of the high yield wheat.2.Different combinations of agronomic traits is one of the best approaches in breeding for further yield increase.This combination of agronomic traits was identified as the best combination.The combination of agronomic traits include the first sheath length,spike length and ratio of grain weight to leaf area.Its genetic advance data is high.Every trait in the combination of agronomic traits is all simple and easy to operate.The combination of agronomic traits can be regarded as important criteria of selection in high-yield wheat breeding.