Seed vigor is an index of seed quality that is used to describe the rapid and uniform germination and the establish- ment of strong seedlings in any environmental conditions. Strong seed vigor in low-temperature germi...Seed vigor is an index of seed quality that is used to describe the rapid and uniform germination and the establish- ment of strong seedlings in any environmental conditions. Strong seed vigor in low-temperature germination conditions is particularly important in direct-sowing rice production systems. However, seed vigor has not been selected as an important breeding trait in traditional breeding programs due to its quantitative inherence. In this study, we identified and mapped eight quantitative trait loci (QTLs) for seed vigor by using a recombinant inbred population from a cross between rice (Oryza sativa L. ssp. indica) cultivars ZS97 and MH63. Conditional QTL analysis identified qSV-1, qSV-Sb, qSV-6a, qSV- 6b, and qSV-11 influenced seedling establishment and that qSV- 5a, qSV-Sc, and qSV-8 influenced only germination. Of these, qSV-1, qSV-Sb, qSV-6a, qSV-6b, and qSV-8 were low-tempera- ture-specific QTLs. Two major-effective QTLs, qSV-1, and qSV-5cwere narrowed down to 1.13-Mbp and 4oo-kbp genomic regions, respectively. The results provide tightly linked DNA markers for the marker-assistant pyramiding of multiple positive alleles for increased low-temperature germination seed vigor in both normal and environments.展开更多
基金supported in part by the National High Technology Research and Development Program of China (2012AA10A304)
文摘Seed vigor is an index of seed quality that is used to describe the rapid and uniform germination and the establish- ment of strong seedlings in any environmental conditions. Strong seed vigor in low-temperature germination conditions is particularly important in direct-sowing rice production systems. However, seed vigor has not been selected as an important breeding trait in traditional breeding programs due to its quantitative inherence. In this study, we identified and mapped eight quantitative trait loci (QTLs) for seed vigor by using a recombinant inbred population from a cross between rice (Oryza sativa L. ssp. indica) cultivars ZS97 and MH63. Conditional QTL analysis identified qSV-1, qSV-Sb, qSV-6a, qSV- 6b, and qSV-11 influenced seedling establishment and that qSV- 5a, qSV-Sc, and qSV-8 influenced only germination. Of these, qSV-1, qSV-Sb, qSV-6a, qSV-6b, and qSV-8 were low-tempera- ture-specific QTLs. Two major-effective QTLs, qSV-1, and qSV-5cwere narrowed down to 1.13-Mbp and 4oo-kbp genomic regions, respectively. The results provide tightly linked DNA markers for the marker-assistant pyramiding of multiple positive alleles for increased low-temperature germination seed vigor in both normal and environments.