小麦抗赤霉病性状的轮回选择效果分析

STUDIES ON RECURRENT SELECTION FOR RESISTANCE TO WHEAT SCAB

为检验轮回选择法在小麦抗赤霉病育种中的应用效果,在人工诱发病害流行的环境中,用三个不同世代的基因库轮选群体进行比较,试验结果表明:随着轮选世代的递增,可育株的发病率、病情指数、平均病小穗数和病粒数都显著减少,群体抗赤霉病性获得增益,同时随轮选次数的增加,组群个体间病小穗数和病粒数的遗传方差随之下降,反映个体间抗性差异的相对减少。在轮选过程中,可育株衍生系的农艺性状逐步获得改良。

Three wheat populations derived from different selection cycles were comparedunder artificial infection condition in field to examine the effect of recurrent selection on improvement of resistance to scab. The results showed that the disease incidence, diseaseindex, average numbers of infected spikelets and infected kernels of male-fertile plants were reduced significantly in advanced populations, Resistance to scab was improved by recurrent selection. Genetic variance for numbers of infected spilelets and kernels of individual plant in populations was reduced with the increase of reeurrent selection number, i. e. variation of disease resistance among plants in populations was reduced relatively by selection. Agronomical character of lines derived from male-fertile plants was improved by recurrent selection.