Characterization of quantitative trait locus for days to heading in near-isogenic lines with genetic background of Indica-type rice variety IR64 (Oryza sativa)

摘要

Days to heading (DTH) is considered as one of the most important traits for rice cultivation. A total of 334 introgression lines (ILs) of rice (Oryza sativa L.), with variation in agronomic traits in the genetic background of an Indica-type variety, 'IR64', were developed and used in this study. Two ILs derived from 'IR65600-87-2-2-3' and 'Hoshiaoba 'showed earlier heading than 'IR64', whereas two ILs from 'IR65598-112-2' and' IR69125-25-3-1-1 'showed later heading. To ascertain the genetic basis of four ILs, quantitative trait loci (QTL) analysis for DTH was conducted using F-2 populations. Three QTLs for short DTH were detected on chromosome 8 in 'IR65600-87-2-2-3' and on chromosomes 6 and 11 in 'Hoshiaoba'. Two QTLs for long DTH were detected on chromosome 6 in 'IR65598-112-2' and on chromosome 11 in 'IR69125-25-3-1-1'. Three near-isogenic lines (NILs) having a QTL from 'IR65600-87-2-2-3' and 'Hoshiaoba' were developed through marker-assisted selection and they showed earlier heading than 'IR64', while two NILs from 'IR65598-112-2' and 'IR69125-25-3-1-1' showed later heading. These NILs for DTH are useful as research and breeding materials.