长江中下游区试水稻品种稻瘟病抗性评价及抗性基因检测

【目的】探究长江中下游区试水稻品种稻瘟病抗性水平及抗性基因聚合对稻瘟病抗性的效应，为新品种的审定及抗病品种的合理利用提供理论依据。【方法】采用人工喷雾接种方法鉴定2018—2020年长江中下游区试252个水稻品种的稻瘟病抗性，并利用2组多重PCR体系（Pi1与Pikh、Pi9与Pik）检测供试水稻品种携带抗性基因Pi9、Pik、Pi1和Pikh的情况，分析抗性基因聚合方式与稻瘟病抗病率的关系。【结果】2018—2020年供试材料的穗瘟抗病率分别为47.0%、38.3%和35.2%，穗瘟抗病率逐年下降。252份供试材料含有抗性基因数为0~4个，其中含0个抗性基因的材料有14份，占5.6%，穗瘟抗病率为14.3%；含1个抗性基因的材料有63份，占25.0%，穗瘟抗病率为11.1%；含2个抗性基因的材料有81份，占32.1%，穗瘟抗病率为42.0%；含3个抗性基因的材料有81份，占32.1%，穗瘟抗病率为65.4%；含4个抗性基因的材料有13份，占5.2%，穗瘟抗病率为53.8%。总体来看，供试材料的穗瘟抗病率随携带的抗性基因数增加呈上升趋势。抗性基因组合Pi9+Pikh、Pi9+Pik+Pikh和Pi9+Pik+Pi1+Pikh是适合安徽地区的抗性基因组合。【结论】2018—2020年长江中下游区试水稻品种稻瘟病抗性一般。多基因聚合能提高水稻品种的稻瘟病抗性，但应选择合适的抗性基因组合，不能简单叠加。

Evaluation of rice blast resistance and detection of resistance genes of rice varieties in regional trials in the middle and lower reaches of Yangtze River

【Objective】To explore the blast resistance level of rice varieties tested in the middle and lower reaches of the Yangtze River and the effect of resistance gene aggregation on the resistance of rice blast and provide a theoretical basis for the approval of new varieties and the rational use of disease-resistant varieties.【Method】The artificial spray inoculation method was used to identify the rice blast resistance of the 252 varieties in regional trials in the middle and lower reaches of the Yangtze River from 2018 to 2020. Two sets of multiplex PCR systems（Pi1 and Pikh，Pi9 and Pik）were used to detect the resistance genes Pi9，Pik，Pi1 and Pikh in the tested rice varieties. The relationship between the aggregation mode of resistance genes and the resistance rate of rice blast was analyzed.【Result】The spike blast resistance rates of the tested materials from 2018 to 2020 were 47.0%，38.3% and 35.2%，respectively，which decreased year by year. 252 tested materials contained 0 to 4 tested resistance genes. There were 14 materials containing no tested resistance genes，accounting for 5.6%，and the spike blast resistance rate was 14.3%；63 materials contained 1 resistance gene，accounting for 25.0%，and the spike blast resistance rate was 11.1%；81 materials contained 2 resistance genes，accounting for 32.1%，and the spike blast resistance rate was 42.0%；81 materials contained 3 resistance genes，accounting for 32.1%，and the spike blast resistance rate was 65.4%；13 materials contained 4 resistance genes，accounting for 5.2%， and the spike blast resistance rate was 53.8%. In general，the spike blast resistance rate of the tested materials increased with the number of resistance genes，showing an upward trend. The rice blast resistance gene combinations Pi9+Pikh， Pi9+Pik+Pikh and Pi9+Pik+Pi1+Pikh were suitable resistance gene combinations in Anhui.【Conclusion】The resistance to blast disease of rice varieties tested in the middle and lower reaches of the Yangtze River from 2018 to 2020 is average. Multi-gene aggregation can improve rice blast resistance，but the appropriate combination of resistance genes should be selected instead of simply superposition.