矮秆基因在中国不同麦区小麦品种中的分布及其对赤霉病抗性的影响

为研究矮秆基因在中国不同麦区的分布，以及株高和小穗密度与赤霉病抗性的相关性，本研究通过分析3个矮秆基因 Rht1、 Rht2和 Rht8在211份不同麦区小麦自然群体中的分布，并结合其在不同环境下株高、小穗密度以及赤霉病抗性的调查数据，分析矮秆基因 Rht1、 Rht2和 Rht8对赤霉病抗性的影响。结果表明：（1）不同麦区矮秆基因的分布频率差异较大， Rht1主要分布在长江中下游麦区， Rht2和 Rht8主要分布在黄淮麦区；（2）与野生型品种相比，携带 Rht1、 Rht2和 Rht8的小麦品种，株高均显著或极显著降低；（3）携带 Rht2和 Rht8的小麦品种，赤霉病抗性均极显著低于野生型品种，而携带 Rht1的小麦品种，赤霉病抗性则极显著高于野生型品种；（4）携带 Rht2和 Rht8的小麦品种，小穗密度显著大于野生型品种，而携带 Rht1的小麦品种，小穗密度则显著降低。因此，不同矮秆基因对小穗密度性状的遗传差异可能是导致小麦赤霉病抗性和不同麦区矮秆基因选择利用差异的部分原因。

Distribution of the Wheat Dwarfing Genes in China and Their Effects on Fusarium Head Blight Resistance

In order to study the distribution of dwarfing genes in different wheat regions of China and the relationship between plant height,spikelet compactness and Fusarium head blight(FHB) resistance. In this study,distribution of three wheat dwarfing genes Rht1, Rht2 and Rht8 in China were investigated with a panel of 211 wheat lines,in combination with the data of plant height,spikelet compactness and FHB resistance of these wheat lines across different locations. The effects of different semi-dwarfing genes on FHB resistance were analyzed. The results showed that the distribution frequency of three dwarfing genes was different among different wheat zones in China. Rht1 mainly distributed in the middle and lower Yangtze River Valleys Autumn-Sown Spring Wheat Zone,whereas Rht2 and Rht8 mainly distributed in the Yellow and Huai River Valleys Facultative Wheat Zone.The plant height of the wheat lines carrying the dwarfing alleles of Rht1, Rht2 and Rht8 showed significant or extremely significant lower than the wide type,and the lines carrying the dwarfing alleles of Rht2 and Rht8 showed significant higher FHB severity,compared with the wide type,whereas the dwarfing allele of Rht1 showed the opposite effect. The spikelet compactness of the lines carrying the dwarfing alleles of Rht2 and Rht8 was significantly increased in comparison with the wide type. However,the dwarfing allele of Rht1 exhibited an effect on reducing the spikelet compactness. Taken together,different effects of the dwarfing genes on FHB resistance might be partly due to their different effects on the spikelet compactness.