Quantitative Trait Loci Mapping for Leaf Length and Leaf Width in Rice cv. IR64 Derived Lines

Abstract

The present study was conducted to identify quantitative trait loci (QTLs) for leaf size traits in IR64 introgression lines (INLs). For this purpose, selected F(2) populations derived from crosses between recurrent parent IR64 and its derived INLs, unique for leaf length and leaf width, were used to confirm QTLs. A total of eight QTLs, mapped on three chromosomes, were identified for the four leaf size traits in six F(2) populations. A QTL for leaf length, qLLnpt-1, in HKL69 was identified around simple sequence repeat (SSR) marker RM3709 on chromosome 1. Two QTLs for flag leaf length, qFLLnpt-2 and qFLLnpt-4, in HFG39 were indentified on chromosomes 2 and 4, respectively. For flag leaf width, a QTL, qFLWnpt-4, in HFG39 was identified around RM17483 on chromosome 4. While another QTL for flag leaf width, qFLWnpt-1, in HFG27 was identified around RM3252 on chromosome 1. A QTL for leaf width, qLWnpt-2, in HKL75 was identified around RM7451 on chromosome 2. For leaf width, two QTLs, qLWnpt-4a, qLWnpt-4b, in HKL48 and HKL99 were identified around RM7208 and RM6909, respectively on chromosome 4. Results from this study suggest the possibilities to use marker-assisted selection and pyramiding these QTLs to improve rice water productivity.

Fine mapping of a major QTL for flag leaf width in rice, qFLW4, which might be caused by alternative splicing of NAL1

“…Alternatively, the regulation of qFLW4 may depend on factor(s) which are polymorphic between HB277 and D50. A similar location on chromosome 4 for a leaf width QTL has been detected in other genetic backgrounds (Ding et al 2011;Farooq et al 2010). The leaf width QTL present in this same interval in cv.…”

“…Further QTL were later identified on 10 of 12 rice chromosomes by analysing a set of recombinant inbred lines (RILs) and a BC 1 F 1 population bred from the same cross (Mei et al 2003(Mei et al , 2005. A similar QTL approach has been taken in other mapping populations (Ding et al 2011;Farooq et al 2010;Li et al 1998;Qian et al 2000;Wang et al 2011;Yue et al 2006), raising the number of relevant QTLs to over 100, distributed over all 12 rice chromosomes (http://www.gramene.org/). However, as yet none of these QTLs has been isolated.…”

Quantitative Trait Locus Mapping and Candidate Gene Analysis for Plant Architecture Traits Using Whole Genome Re-Sequencing in Rice

“…Marathi et al (2012) reported 19 novel QTLs and 15 QTL hotspots affecting plant architecture, including yield-related traits, using RILs developed from Pusa1266, a semi-dwarf, high-yielding cultivar. Further work identified several other QTLs regulating plant shape, including leaf length, leaf width, tiller number and panicle length (Farooq et al, 2010; Liu et al, 2010; Wang et al, 2010; 2011). Modifying plant architecture for architecture-based breeding will require identification of QTLs and their causal genes in different genetic backgrounds.…”

QTLs for rice flag leaf traits in doubled haploid populations in different environments

“…Among these QTLs, 1 QTL on chromosome 8 controlling length, width, and flag leaf area was at the same location. Since then, QTL mapping for flag leaf traits has been extensively conducted in different types of genetic populations, such as near isogenic lines, backcross inbred lines, doubled haploids (DHs), and F 2 , with more than 100 QTLs identified (Dong et al, 2003;Kobayashi et al, 2003;Shen et al, 2003;Wang et al, 2004;Yue et al, 2006;Cao et al, 2007;Tong et al, 2007;Farooq et al, 2010;Ding et al, 2011;Wang et al, 2011;Sonah et al, 2012;Chen et al, 2012). For example, Kobayashi et al (2003) mapped QTLs for FLL, FLW, and FLA using the Milyang23/Akihikari RIL population over 5 seasons, and found a total of 9 genomic regions involved in leaf development.…”