Correlation Of Earliness Traits And Qtl Mapping In Processing Tomato

Object:Earliness processing tomato is an important resource of tomato in Xinjiang.The tomato catchup is famous of its good qulity because of Xinjiang's special sunray,heat and water and so on.The frost-free period is so short and the early frost is so hard that the planting of earliness processing tomato is very important.The maturing stage of processing tomato belongs to quatitive traits which is controlled by multigene and its hereditary basis is very complicated.The research of quatitive trait has made great progress because of the application of molecular marker.SSR(simple sequence repeats) is an deoxyribose nucleic acid(DNA) marker which bases on polymerase chain reaction (PCR) and which has the characteristic of rich polymorphism and high stability.Methods:Based on 202 F2:3 family lines from cross between TD-13xTD-41, a combined SSR genetic map of processing tomato has been constructed and an initial QTL mapping of processing tomato has been performed.Results:1.The statistic analysis of quality traits of parents and F2:3 family lines showed that each quality trait which is controlled by multi-minor genes is in accordance with normal distribution.The analysis of correlation of earliness traits between growth periods show that the MS was positively correlated with DFF,FFN,FP and DFM.DFF was negtively correlated with DFM and EFN.AWF was positively correlated with DFF but negatively with FP and EFN.2.500 tomato SSR primers are used for parents screening and 125 clear and reproducible polymorphic SSR primers are selected.Then these selected primer are used to analyze 202 F2 population which is from the cross between processing tomato TD-13 and TD-41,constructing genetic linkage map including 2 linkage groups and 54 markers through the analysis of 123 marker sites.The distance of linkage group covering 158 cM and the marker numbers varies from 2 to 54.The average distance of markers is 2.87cM,the shortest is 0.17cM,the longest is 41cM.3.A total of 12 QTLs were detected by composite interval mapping with software MapQTL5.02 QTLs have been detected for DFF and AWF in F2 groups.We have found 10 QTLs in F2:3 family lines which includs 2 QTLs for DFF and 3 QTLs for FFN which around of primer SSR40;2 QTLs for MS and AWF;1 QTL for DFM and EFN.Conclusion:This research has investigated each trait of growth periods in two years.With the application of software MapQTL5.0QTL intensive location was found.We have detected several QTLs about FFN,MS,EFN,DFM around primer LEaat006-LEat016.