摘要
Quantitative trait loci （QTLs） contributing to salt tolerance during the vegetative stage in tomato were investigated. A moderately salt-sensitive Lycopersicon esculentum Mill.‘XF 98-7’ was hybridized with a salt-tolerant Lycopersicon pimpinellifolium accession LA2184, and F2 and F3 populations were developed. The F2 population was used for SSR mapping and the F3 families were evaluated for salt tolerance in solution cultures containing 1% NaCl. A LOD score threshold of 2.0 was chosen to identify putative QTLs and to estimate their additive effect and phenotypic variation. Two genomic regions （LEtat003-SSR139, SSR119-SSR17） were detected on chromosome 4 beating significant QTLs for salt tolerance, respectively accounted for 6.03% and 8.01% of the phenotypic variation. The QTL in the marker interval of LEtat003-SSR139 showed significant negative effects, while the other QTL in the marker interval of SSR119-SSR17 showed significant positive effects. The identification of genomic locations with both positive and negative effects on this trait suggests the likelihood of recovering transgressive segregants in progeny derived from these parental lines. Results and its application in developing salt-tolerant tomatoes as molecular markers are discussed in this paper.
Quantitative trait loci (QTLs) contributing to salt tolerance during the vegetative stage in tomato were investigated. A moderately salt-sensitive Lycopersicon esculentum Mill.‘XF 98-7’ was hybridized with a salt-tolerant Lycopersicon pimpinellifolium accession LA2184, and F_2 and F_3 populations were developed. The F_2 population was used for SSR mapping and the F_3 families were evaluated for salt tolerance in solution cultures containing 1% NaCl. A LOD score threshold of 2.0 was chosen to identify putative QTLs and to estimate their additive effect and phenotypic variation. Two genomic regions (LEtat003-SSR139, SSR119-SSR17) were detected on chromosome 4 beating significant QTLs for salt tolerance, respectively accounted for 6.03% and 8.01% of the phenotypic variation. The QTL in the marker interval of LEtat003-SSR139 showed significant negative effects, while the other QTL in the marker interval of SSR119-SSR17 showed significant positive effects. The identification of genomic locations with both positive and negative effects on this trait suggests the likelihood of recovering transgressive segregants in progeny derived from these parental lines. Results and its application in developing salt-tolerant tomatoes as molecular markers are discussed in this paper.
基金
Item supported by national 863 high-techproject(grand No.2001AA67010)
