小麦品种对赤霉病抗扩展组分的通径分析

 应用通径分析和逐步回归相结合的统计方法，研究了小麦品种对赤霉病的抗扩展组分。结果表明，病害引起的产量损失由病粒数和病穗中的无病籽粒重降低率构成，这二个组分主要取决于病小穗数的多少，穗轴病节片数及穗轴发病时间这二个组分主要通过影响病小穗数而对产量损失起作用。接种至显症天数对产量损失无显著作用，与其他抗扩展组分也没有显著相关。

THE PATH ANALYSIS OF THE EXPANSION RESISTANCE COMPONENTS TO SCAB IN WHEAT VARIETIES

The expansion resistance components to scab in wheat varieties were studied by means of statistical procedure of path analysis combined with stepwise regression. The results show that yield loss caused by scab includes the number of the infected kernels and the declined rate of uninfected kernel weight in diseased spike, which are decided by the number of diseased spikelets. The number of diseased segments on rachis and the rate of disease spreading to rachis acting on yield mainly through affecting the number of diseased spikelets. However, the days from inoculation to appearance of symptoms have no marked influence on yield loss and no notable correlation with other expansion resistance components.