玉米穗腐病是影响我国玉米生产的主要病害之一，严重影响玉米的产量和品质。因此，开展玉米穗腐病抗性的遗传学研究，对培育抗玉米穗腐病品种，保障玉米生产与粮食安全具有重要的意义。本研究以3个高抗玉米自交系承351、丹598、吉V203和1个高感自交系ZW18为亲本，分别构建了3个F2群体及其对应的F2:3家系，通过对F2:3家系发病果穗进行图像处理的方法鉴定抗病表型，对禾谷镰孢穗腐病抗性进行QTL定位。3个F2群体共检测到11个与禾谷镰孢穗腐病抗性有关的QTLs，分别可解释4.87-40.98%的表型变异率。其中来源于抗病亲本承351的QTL-qRgr7-1位于7.02 bin，可解释高达13.76-40.98%的表型变异率。另外，通过与前期病害评级方法定位到的QTLs相比，qRgr7-1在Bins7.02上和qRger7.1完全重合；qRgr2-1在Bins2.01-2.02上和qRger2.1完全重合；qRgr10-1在Bins10.01-10.02上和qRger10.1完全重合；基于图像分析定位到的qRgr9-1、qRgr1-2、qRgr3-1分别与基于抗病评级定位到的区间存在重叠区域。利用不同方法定位到了相同的QTLs，一方面说明基于图像分析进行表性鉴定有一定的准确性，另一方面也验证了这些QTLs位点的真实性。本研究为禾谷镰孢穗腐病抗性QTL的精细定位和玉米穗腐病的抗性遗传改良提供了重要的遗传资源和参考信息 。

Maize ear rot is one of the main diseases affecting maize production in China, which seriously affects the yield and quality of maize. Therefore, genetic study on resistance to ear rot, are extremely important for ear rot resistance breeding in maize and ensuring maize production and food security. In this study, three highly resistant inbred lines Cheng351, Dan598, JiV203 and one highly susceptible inbred line zw18 were used for constructing three F2 populations and their corresponding F2:3 families for QTL mapping of resistance to Gibberella ear rot in maize. The disease resistance were identified by image processing of diseased ears fromF2：3 families. A total of 11 QTLs were detected in the three F2 populations, which respectively explained 4.87 - 40.98% of the phenotypic variation. The QTL-qRgr7-1 from the resistant parent Cheng 351 was located on 7.02 bin, accounting for as high as 13.76 - 40.98% of the phenotypic variation. In addition, compared with QTLs located by the previous disease rating method, qRgr7-1 was completely coincident with qRger7.1 on Bins7.02. qRgr2-1 completely coincident with qRger2.1 on bins2.01-2.02. qRgr10-1 completely coincident with qRger10.1 on bins10.01-10.02. qRgr9-1, qRgr1-2 and qRgr3-1 overlaps with the interval located based on disease resistance rating respectively. The results show the surface identification based on image analysis has accuracy, and on the other hand verified the authenticity of these QTLs loci. This study provided important genetic resources and reference information for fine mapping of QTLs and genetic improvement of resistance to Gibberella ear rot in maize.

吉林省发改委产业技术研究与开发项目(2020C019-4),吉林省科技厅中央引导地方科技发展资金(202002072JC)作者简介王梓钰(1986-),助理研究员,从事作物分子育种研究。Tel: 0431-87063713, E-mail:wangzy86@foxmail.com 玉米禾谷镰孢穗腐病抗性的QTL定位