Li Wen-Xia, Wang Ping, Zhao Hengxing, Sun Xu, Yang Tao, Li Haoran, Hou Yongqin, Liu Cuiqiao, Siyal Mahfishan, Raja Veesar Rameez, Hu Bo, Ning Hailong
Key Laboratory of Soybean Biology, Ministry of Education, Key Laboratory of Soybean Biology and Breeding/Genetics, Ministry of Agriculture, Northeast Agricultural University, Harbin, China.
High Education Institute, Huaiyin Institute of Technology, Huai'an, China.
Front Plant Sci. 2021 Aug 20;12:666796. doi: 10.3389/fpls.2021.666796. eCollection 2021.
Although the main stem node number of soybean [ (L.) Merr. ] is an important yield-related trait, there have been limited studies on the effect of plant density on the identification of quantitative trait loci (QTL) for main stem node number (MSNN). To address this issue, here, 144 four-way recombinant inbred lines (FW-RILs) derived from Kenfeng 14, Kenfeng 15, Heinong 48, and Kenfeng 19 were used to identify QTL for MSNN with densities of 2.2 × 10 (D1) and 3 × 10 (D2) plants/ha in five environments by linkage and association studies. As a result, the linkage and association studies identified 40 and 28 QTL in D1 and D2, respectively, indicating the difference in QTL in various densities. Among these QTL, five were common in the two densities; 36 were singly identified for response to density; 12 were repeatedly identified by both response to density and phenotype of two densities. Thirty-one were repeatedly detected across various methods, densities, and environments in the linkage and association studies. Among the 24 common QTL in the linkage and association studies, 15 explained a phenotypic variation of more than 10%. Finally, , and were predicted to be associated with MSNN. These findings will help to elucidate the genetic basis of MSNN and improve molecular assistant selection in high-yield soybean breeding.
虽然大豆[（L.）Merr.]的主茎节数是一个与产量相关的重要性状，但关于种植密度对主茎节数（MSNN）数量性状位点（QTL）鉴定的影响的研究有限。为了解决这个问题，本文利用由垦丰14、垦丰15、黑农48和垦丰19衍生的144个四向重组自交系（FW-RILs），通过连锁和关联研究在五个环境中以2.2×10（D1）和3×10（D2）株/公顷的密度鉴定MSNN的QTL。结果，连锁和关联研究分别在D1和D2中鉴定出40个和28个QTL，表明不同密度下QTL存在差异。在这些QTL中，有5个在两种密度下是共同的；36个是针对密度响应单独鉴定的；12个是通过密度响应和两种密度的表型反复鉴定的。在连锁和关联研究中，有31个在各种方法、密度和环境中被反复检测到。在连锁和关联研究中共同的24个QTL中，有15个解释了超过10%的表型变异。最后， 、 和 被预测与MSNN相关。这些发现将有助于阐明MSNN的遗传基础，并改善高产大豆育种中的分子辅助选择。
