QTL Mapping of Yield and Yield Components in Barley Lines

This study was conducted to identify QTLs controlling yield and yield components in 99 F13 recombinant inbred lines (RILs) derived from barley cross Azumamugi × Kanto Nakate Gold. The parents and inbred lines were evaluated for agronomic characteristics including spike number per m2, kernel number per spike, kernel weight per spike, kernel yield, and 1000 kernels weight. Field trails were conducted as randomized complete block design with two and three replications for 2 planting years, respectively. Significant differences and transgrassive segregants were observed among lines for all of the traits. To identify QTL, composite interval mapping (CIM) was done based on linkage map constructed using 99 RILs and 2 morphological, 2 isozyme, 34 STS and 62 AFLP markers. New QTL controlling spike number/m2 was identified in this population. The QTL explained 10% of the phenotypic variation, was located in the map interval of ABG604-e09m28.8.2 on chromosome 5HL. The QTL detected in the map interval of vrs1-MWG503 on chromosome 2HL could explain most of the phenotypic variation for kernel number per spike, kernel yield and 1000-kernel weight. Most of the phenotypic variation for kernel weight per spike was explained by the QTLs located in the map interval of vrs1-MWG503 and MWG801-vrs1 on chromosome 2H. The results revealed that important QTLs controlling most of the traits were located near by two and six-rowed spike gene vrs1.