Wild-QTL-allele effect in the background of japonica Nipponbare and indica (IR36) cultivars

摘要

To identity useful quantitative trait loci (QTL) alleles from wild rice relatives, an accession of wild rice Oryza rufipogon from Myanmar was crossed with one japonica (Nipponbare) and one indica (IR36) cultivar. In the BC_2 generation using O. salivaas the recurrent parent, 11 morphological characters (days to heading, photosynthesis activity, culm and panicle length, number of tillers, yield, 100-seed weight, seed length and width, grain length and width) were evaluated with the two populations, consisting of approximately 200 plants each. Single-point QTL analysis was carried out with about 75 microsatellite markers almost covering the rice genome. A total of 55 and 51 QTLs were identified at a significance of P<0.01 with the backcrossed populations of Nipponbare and IR36, respectively. Of these, 29 (52,7%) and 28 (54.9%), respectively, had wild alleles increasing trait values. The effect of the wild QTL alleles in the background of these rice cultivars was examined, and six QTL locations werefound to-be common between two populations. Regarding the wild QTL alleles increasing yield, one QTL location on chromosome 1 was detected in both indica and japonica background populations, whereas two and three were found to be specific to japonica andindica background populations, respectively.