玉米耐深播主效QTL qMES20-10的精细定位及差异表达基因分析

Drought stress is a major threat to maize ( Zea mays L.) yield. Deep-seeding tolerant maize variety can absorb water in deep soil and thus have strong drought tolerance. Therefore, it is of great theoretical and practical importance to study the genetic mechanism of deep-seeding tolerance. In our previous work, we identified a major QTL qMES20-10 controlling maize deep-seeding tolerance on chromosome 10 using an F2:3 population derived from a deep-seeding tolerant inbred line 3681-4 and a common inbred line X178. In this study, a BC3F3:4 population was constructed through background and foreground selection using X178 as the recurrent parent. The major QTL, qMES20-10 , was firstly verified in this BC3F3:4 population. Furthermore, advanced backcross population was constructed through marker-assisted selection, and qMES20-10 was fine-mapped within the interval of 133.3–136.0 Mb on chromosome 10. Moreover, RNA-Seq analysis of two near-isogenic lines screened from the BC3F3:4 families identified the differentially expressed genes, mainly involved in chemical stimulus response, oxidation reduction, and oxidative stress response. These results lay a foundation of further cloning the major QTL qMES20-10.