Euphytica (2014) 198:199–209         DOI 10.1007/s10681-014-1092-6

Identification of QTLs for seedling vigor in winter wheat

Xing-Mao Li • Xin-Min Chen • Yong-Gui Xiao • Xian-Chun Xia • De-Sen Wang • Zhong-Hu He • Hua-Jun Wang

Received: 12 October 2013/Accepted: 24 February 2014/Published online: 19 March 2014 Springer Science+Business Media Dordrecht 2014

Abstract Seedling vigor is an important trait characterized by rapid development of vegetative cover above the soil surface, particularly in rainfed environments. To elucidate thegenetic basis of seedling vigor, 207F2:4 linesderivedfromJingdong8/Aikang58were investigated in the field at Beijing and Gaoyi, Hebei province, during the 2011–2012 and 2012–2013 cropping seasons. A total of 148 SSR markers polymorphic between the parents, and the RhtD1b-specific marker were used to map QTL for seedling vigor by inclusive composite interval mapping (ICIM). Normalized difference vegetation index (NDVI) and ground cover (GC) before winter and in late spring showed a continuous distribution. Significant differences in NDVI and GC among lines were detected. BroadsenseheritabilityofNDVIandGCrangedfrom0.69to 0.74 based on the mean values averaged across four environments. GC was highly correlated with NDVI (r = 0.74–0.85, P\0.001). Four seedling traits were positively correlated with thousand kennel weight and grain yield. Thirty-seven QTLs distributed on 14 chromosomes for the seedling traits were identified; 18 were on genome A chromosomes, 8 on genome B chromosomes and 11 on genome D chromosomes. QTLs QGCs.caas-3B.1, QGCw-caas-1D and QGCwcaas-5D explained more than 20 % of the phenotypic variation in seedling traits, with over-dominance effects. QGCw.caas-1A.1, QNDVIw-caas-6D, QGCscaas-6A, QGCs-caas-2A.2, QNDVIs-caas-3A, and QGCw-caas-5B explained more than 10 % of the phenotypic variation in seedling traits. The major QTLs QGCs-caas-6A and QGCw.caas-5B showing strong additive effects and linked with agronomic traits, could be used for molecular marker-assisted selection to improve seedling vigor and yield-related traits.

Keywords Bread wheat Normalized difference vegetation index (NDVI) Ground cover (GC) Quantitative trait locus (QTL)

X.-M. Li H.-J. Wang (&) Gansu Key Lab of Crop Improvement & Germplasm Enhancement, Gansu Agricultural University, Lanzhou 730070, China e-mail: whuajun@yahoo.com
X.-M. Li X.-M. Chen Y.-G. Xiao X.-C. Xia D.-S. Wang Z.-H. He (&) Institute of Crop Science, National Wheat Improvement Center, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100081, China e-mail: zhhecaas@163.com
X.-M. Li Dryland Agriculture Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China
Z.-H. He CIMMYT China Office, Beijing 100081, China