Table1_Identification of the Powdery Mildew Resistance in Chinese Wheat Cultivar Heng 4568 and its Evaluation in Marker-Assisted Selection.XLSX

Powdery mildew induced by Blumeria graminis f. sp. Tritici (Bgt) has a devastating impact on global wheat yield and quality. Host resistance is the most effective and economical means to control this disease. In this study, Heng 4568, an elite wheat cultivar, shows high resistance to 12 Bgt isolates from different regions in China at the seedling stage. Genetic analysis demonstrates that the powdery mildew resistance in Heng 4568 is conferred by a single dominant locus, temporarily designated PmH4568. Furthermore, PmH4568 is mapped to the reported Pm2 interval on chromosome 5DS with five Pm2 linked markers and flanked by the markers Bwm20 and Bwm21 with a genetic distance of 0.3 and 0.6 cM, respectively. To further investigate the relationship between PmH4568 and Pm2, the diagnostic marker Pm2b-map-3 of Pm2 is used to genotype the F2:3 population derived from the cross Heng 4568 × Daimai 2173. Notably, there is no recombination found, indicating that PmH4568 is also probably a Pm2 allele. In addition, five closely linked markers as well as one diagnostic marker are successfully developed and tested in 16 wheat cultivars from different agro-ecological areas in China, which have potential applications in molecular breeding by marker-assisted selection.

由禾本科布氏白粉菌小麦专化型（Blumeria graminis f. sp. Tritici, Bgt）引发的小麦白粉病，对全球小麦产量与品质造成毁灭性危害。寄主抗性是防控该病害最为经济有效的手段。本研究中，优良小麦品种衡4568在苗期对采自中国不同区域的12个Bgt菌株表现出高抗特性。遗传分析结果表明，衡4568的白粉病抗性由单个显性位点调控，该位点暂命名为PmH4568。进一步研究显示，PmH4568定位于已报道的5DS染色体上的Pm2区间，可通过5个与Pm2连锁的标记进行定位；其侧翼标记为Bwm20与Bwm21，对应的遗传距离分别为0.3 cM和0.6 cM。为深入解析PmH4568与Pm2的遗传关系，本研究利用Pm2的诊断标记（diagnostic marker）Pm2b-map-3，对杂交组合衡4568 × 岱麦2173所衍生的F2:3群体进行基因型分型。结果未检测到重组事件，这提示PmH4568大概率属于Pm2的等位基因。此外，本研究成功开发并验证了5个紧密连锁标记及1个诊断标记，将其应用于来自中国不同农业生态区的16个小麦品种的基因型鉴定，上述标记在标记辅助选择（marker-assisted selection）分子育种中具备潜在应用价值。