Host-pathogen relationship in scab disease

本文对引起赤霉病的病原菌镰刀菌（Fusarium graminearum Schwabe）生理小种的分化进行了分析。采用“截穗”接种法，将110株镰刀菌分别接种于10个大麦和15个小麦品种上。记录侵染小花（大麦）和小穗（小麦）的百分率，并转化为角度进行统计分析。大麦品种x系和小麦品种x系相互作用不显著，寄主品种间相关系数均大于0.8，表明种内基因对基因的分化不显著。另一方面，方差分析和主成分分析表明，菌株x寄主种（大麦和小麦）之间的互作具有统计学意义。而寄主种间的相关系数高达0.8。因此，镰刀菌菌株对不同寄主品种大麦和小麦的致病性略有差异。

The differentiation of physiological races in Fusarium graminearum Schwabe, a causal fungus of scab disease was analyzed in this study.A total of 110 Fusarium strains was inoculated onto ten barley and 15 wheat varieties separately by 'cut-spike' inoculation method. Percentage of infected florets (barley) and spikelets (wheat) was recorded and it was transformed into the degree of angle for the statistical analyzes.Both barley variety x strain and wheat variety x strain interactions were not remarkable and the correlation coefficients among host varieties were more than 0.8, suggesting that the gene-for-gene differentiation within species was not significant.On the other hand, the variance analysis and the principal component analysis revealed that interaction between strain x host species i.e.barley and wheat is statistically significant. Whereas the correlation coefficients among host species were as high as 0.8. Therefore the pathogenicity of Fusarium strains differentiated slightly against the different host species, barley and wheat.