QTL Mapping Of Fruit Traits And Superior Genotypes Selecting In Chinese Jujube (Zizyphus Jujuba Mill. )

Jujube (Zizyphus jujuba Mill.), belongs to Zizyphus, Rhamnaceae family, was one of the particular economic fruit trees in China. High yield, good quality and strong resistance were the main targets for Chinese jujube breeding. Application of markers assistant selection (MAS) could improve the efficiency greatly and shorten breeding cycles in Chinese Jujube breeding. In this study, 4 EST-SSR markers were joined into the AFLP genetic maps based on the F1 population with 150 plants derived from a cross between Dongzao and Linyilizao. After that, some QTLs linked to fruit size traits were located on the molecular genetic map.With AFLP markers from Shen lian-ying’s study and SSR markers of this research, 4 SSR markers were mapped into SLG3, SLG6, SLG9 and SLG19 linkage groups, BFUPXM6 located in the tail of SLG3 linkage groups, BFUPXM18 located in the region near the marker EgtMcag(18)m of SLG6, BFUPXM7 located between EaggMat207(29)h and EacaMctal80(10)m in SLG9, BFUPXM24 located the top of SLG13 linkage groups.16 QTLs affecting fruit size were located on the genetic linkage map with MapQTL4.0 software using interval mapping method, 16 QTLs were mapped on 6 linkage groups, 6 QTLs were on SLG4 linkage groups. 7 QTLs for fruit weight were located onto linkage group 4, 6 and 13, and total explained the genetic variance of 88%, 54.1% and 138.6%, individual QTL accounted for 7.2%-14.4%; 6 QTLs for transverse diameter were located on linkage group 4 and 9, and total explained the genetic variance of 51.4% and 22.7%, individual QTL accounted for 8%-9%; 4 QTLs for vertical diameter were located on linkage group 4 and 13, and total explained the genetic variance of 68.8% and 82.1%, individual QTL accounted for 5.2%-7.2%; 2 QTLs for fruit index were located on linkage group 6 and 8, and explained the genetic variance of 29.4% and 59.2%, Every one of the QTLs affecting traits of fruit index could explain 0.3%-0.6% variation. QTLs related to fruit size traits closely distributed on SLG4.The trait segregation of branch, leaf, fruit weight, and fruit shape of hybrids from Dongzao×Linyilizao,Dongzao seedlings and Jixinzao seedlings were studied. The results showed that the fruit weight presented obvious segregation, and their variance coefficient was 42%, 51%and41%, respectively; Variance of length between nodes on the trunk, fruit weight, Vertical and horizontal diameters of the fruit, soluble solid was more than 15% respectively. Based on the sensory evolution of natural pollinated Chinese Jujube seedlings, large fruit type, early maturity type, wild jujube type and crack-resistant type were regarded as candidates in the further selection.The research results could be directly used as a basis for molecular marker-assisted breeding and laid a foundation for quality, yield, and crack-resistant of breeding in Chinese Jujube.