Bayesian analysis of interacting quantitative trait loci (QTL) for yield traits in tomato

Abstract

An F₂ population derived from the hybrid of Lycopersicon esculentum Mill.XF98-7×Lycopersicon pimpinellifolium LA2184 was used for genome-wide linkage analysis for yield traits in tomato. The genetic map, spanning the tomato genome of 808.4 cM long was constructed with 112 SSR markers distributing on 16 linkage groups. Main and epistatic effect QTLs controlling first flower node, number of flowers per truss, fruit set percentage and fruit weight were located using Bayesian model selection method. A total of 20 significant main effect QTLs and 16 pairs of epistatic QTLs were identified on 16 linkage groups. The proportions of phenotypic variation explained by the detected QTLs ranged from 1.9 to 25.9% and from 0.00 to 17.4% for main-effect and epistatic QTLs, respectively. Most QTL effects were predictable from the parental phenotypes. Additionally, one QTL was found to be pleiotropic, governing simultaneously first flower node and number of flowers per truss.

Key words: Tomato, SSR marker, yield traits, QTL, Bayesian model selection.