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玉米粗缩病是近年严重影响中国玉米生产的病害,研究其QTL定位有助于利用分子标记辅助选择提高玉米粗缩病抗性育种效率。该研究调查了GY220×1145杂交衍生的重组自交系(RIL)群体109个家系(F10∶11)在2个环境下粗缩病的抗感表型值,结合该组合由272个DNA分子标记构建的遗传连锁图谱,分别采用基于多元回归模型的Win QTL Cartographer 2.5软件的复合区间作图法(CIM)和基于混合线性模型的QTL Network 2.0软件中CIM方法,检测了玉米粗缩病的抗性位点。结果表明:(1)运用Win QTL Cartographer 2.5软件中CIM法,检测到5个抗玉米粗缩病的QTL,解释表型变异的6.9%～17.6%,其中有3个QTL在2个环境下都检测到。5个QTL的加性效应变异幅度为-8.57～11.94。(2)用QTL Network 2.0软件中CIM法,检测到1个控制玉米粗缩病的位点MRDD2-22,解释表型变异的9.0%,加性效应为6.93。在第5连锁群与13连锁群之间存在1对非主效QTL间的互作,解释表型变异的7.4%,互作效应为-7.70。运用多元回归模型和混合线性模型都检测到的位点是MRDD2-22,位于第4染色体长臂g7M7806～n142标记区间,抗性等位基因来自自交系1145,平均加性效应为9.3。MRDD2-22位点可用于分子标记辅助选择进行玉米自交系粗缩病抗性的改良。
In recent years, the maize rough cucumber disease seriously affects the production of maize in China. Studying its QTL mapping will help to improve the breeding efficiency of maize cucumber disease resistance by molecular marker-assisted selection. This study investigated the resistance phenotype of 109 families (F10:11) of GY220 × 1145 hybrid derived recombinant inbred line (RIL) population in two environments, combining the combination of 272 DNA molecular markers The constructed genetic linkage map was used to detect the resistance to maize rough-set by CIM in Win QTL Cartographer 2.5 software based on multiple regression model and CIM method in QTL Network 2.0 software based on mixed-linear model respectively Site. The results showed that: (1) Five QTLs for resistance to maize rough were detected using the CIM method in Win QTL Cartographer 2.5 software, accounting for 6.9% ~ 17.6% of phenotypic variation. Three QTLs were detected in two environments detected. The amplitudes of additive effects of five QTLs ranged from -8.57 to 11.94. (2) Using the CIM method in QTL Network 2.0 software, we detected 1 locus MRDD2-22 that controls maize slippage, explained 9.0% of phenotypic variation, and the additive effect was 6.93. Between QTL 5 and QTL 13, there was an interaction between QTLs in a pair of non-QTLs, accounting for 7.4% of phenotypic variation and an interaction effect of -7.70. The loci detected by multiple regression model and mixed linear model were MRDD2-22, located on the long arm of chromosome 4 from g7M7806 to n142, and the resistant allele was from inbred line 1145 with an average additive effect of 9.3. The MRDD2-22 locus can be used for molecular marker-assisted selection to improve the resistance of cucumber to inbreeding.