To increase the thermotolerance of improved White Ponni(IWP), two quantitative trait loci(QTLs), q HTSF1.1 and q HTSF4.1, controlling spikelet fertility under high-temperature stress, were introgressed from Nagina...To increase the thermotolerance of improved White Ponni(IWP), two quantitative trait loci(QTLs), q HTSF1.1 and q HTSF4.1, controlling spikelet fertility under high-temperature stress, were introgressed from Nagina 22 into IWP through marker-assisted breeding. The progenies were subjected to foreground selection of target QTLs using simple sequence repent markers RM431 and RM5757 linked to q HTSF1.1 and q HTSF4.1, respectively. At each generation, foreground selection with single target QTL or both QTLs was done together. The QTL-positive plants were forwarded to next generation by selfing. The F2:3 progenies were subjected to phenotypic analyses under high-temperature stress at the flowering stage. Chlorophyll stability index, malondialdehyde content, grain yield, and yield-related components of the F2:3 progenies were measured. The progenies IWP-295, IWP-277 and IWP-246 harboring both q HTSF1.1 and q HTSF4.1 showed higher fertility percentages under high-temperature stress at the flowering stage. These QTLs were responsible for maintaining membrane integrity and yield under elevated temperature conditions.展开更多
基金supported by the Department of Biotechnology,New Delhi(Grant No.BT/PR10593/AG2 II/106/936/2014)
文摘To increase the thermotolerance of improved White Ponni(IWP), two quantitative trait loci(QTLs), q HTSF1.1 and q HTSF4.1, controlling spikelet fertility under high-temperature stress, were introgressed from Nagina 22 into IWP through marker-assisted breeding. The progenies were subjected to foreground selection of target QTLs using simple sequence repent markers RM431 and RM5757 linked to q HTSF1.1 and q HTSF4.1, respectively. At each generation, foreground selection with single target QTL or both QTLs was done together. The QTL-positive plants were forwarded to next generation by selfing. The F2:3 progenies were subjected to phenotypic analyses under high-temperature stress at the flowering stage. Chlorophyll stability index, malondialdehyde content, grain yield, and yield-related components of the F2:3 progenies were measured. The progenies IWP-295, IWP-277 and IWP-246 harboring both q HTSF1.1 and q HTSF4.1 showed higher fertility percentages under high-temperature stress at the flowering stage. These QTLs were responsible for maintaining membrane integrity and yield under elevated temperature conditions.