Identifying novel QTLs for submergence tolerance in rice cultivars IR72 and Madabaru |
| |
Authors: | Email author" target="_blank">Endang?M?SeptiningsihEmail author Darlene?L?Sanchez Namrata?Singh Pamella?M?D?Sendon Alvaro?M?Pamplona Sigrid?Heuer David?J?Mackill |
| |
Institution: | (1) International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines;(2) Present address: MARS Food Global, Department of Plant Science, University of California, Davis, CA 95616, USA |
| |
Abstract: | Short-term submergence is a recurring problem in many rice production areas. The SUB1 gene, derived from the tolerant variety FR13A, has been transferred to a number of widely grown varieties, allowing them
to withstand complete submergence for up to 2 weeks. However, in areas where longer-term submergence occurs, improved varieties
having higher tolerance levels are needed. To search for novel quantitative trait loci (QTLs) from other donors, an F2:3 population between IR72 and Madabaru, both moderately tolerant varieties, was investigated. After a repeated phenotyping
of 466 families under submergence stress, a subset of 80 families selected from the two extreme phenotypic tails was used
for the QTL analysis. Phenotypic data showed transgressive segregation, with several families having an even higher survival
rate than the FR13A-derived tolerant check (IR40931). Four QTLs were identified on chromosomes 1, 2, 9, and 12; the largest
QTL on chromosome 1 had a LOD score of 11.2 and R
2 of 52.3%. A QTL mapping to the SUB1 region on chromosome 9, with a LOD score of 3.6 and R
2 of 18.6%, had the tolerant allele from Madabaru, while the other three QTLs had tolerant alleles from IR72. The identification
of three non-SUB1 QTLs from IR72 suggests that an alternative pathway may be present in this variety that is independent of the ethylene-dependent
pathway mediated by the SUB1A gene. These novel QTLs can be combined with SUB1 using marker assisted backcrossing in an effort to enhance the level of submergence tolerance for flood-prone areas. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|