关键词: 野生二粒小麦, 抽穗期, 单株有效穗数, 穗粒数；穗长, 芒长, 数量性状基因位点(QTL)

Abstract:

Wild emmer wheat, Triticum dicoccoides, is the progenitor of modern tetraploid and hexaploid cultivated wheats, which genepool harbor a rich allelic repertoire for various traits. In this paper, the genetic and phonotypic basis of spike traits, e.g. heading stage (HS), spike number per plant (SPP), kernel number per spike (KNS), spike length (SL), and awn length (AL) were studied in tetraploid wheat population consists of 152 F6 recombinant inbreed lines (RILs) derived from a cross between T. dicoccoides (acc# G18-16) and durum wheat cultivar (Langdon) grown in the central region of Guizhou Province, China. Wide genetic variation was found among RILs for all studied traits. A total of 14 QTL effects associated with five spike related traits were detected, with a LOD score range of ca.1.9 to 13.4. The identified QTLs included: three QTLs for HS located on chromosomes 3A (2 QTLs) and 7B, explaining phenotypic variation 54.2 and 9.4%; three QTLs for KNS, located on chromosomes 2A (2 QTLs) and 5A, explaining 14.6 and 24.3 of phenotypic variation; two QTLs for SPP, located on chromosome 5B (2 QTLs), explaining 44.7% of phenotypic variation; three QTLs for SL, located chromosomes 5A (2 QTLs) and 7A，explaining 54.2 and 9.4 of phenotypic variation; three QTLs for AL, located chromosomes 4B, 5A and 7A, explaining 7.3, 7.8 and 9.8 of phenotypic variation, respectively. The identified QTLs could be useful in future marker-assisted selection programs, facilitating the use of wild alleles for yield enhancement in elite wheat cultivars.

Key words: Triticum dicoccoides, Heading stage； Spike number per plant； Kernel number per spike； Spike length； Awn length； Quantitative trait locus (QTL)