QTL Analysis For Figure Traits And Needle Traits In Chinese Jujube

Chinese Jujube {Ziziphus jujuba Mill.) originated from China, belongs to Ziziphus, Rhamnaceae family, is one kind of important economic fruit tree in China. It is of great value to understand trait's molecular genetic regulation and select them effectively for jujube breeding purpose. In this study, a high-density molecular genetic map for Chinese jujube was constructed with AFLP and RAPD markers, based on a F1 segregation population derived from a cross between Dongzao {Ziziphus jujuba Mill. cv. Dongzao) and Linyilizao {Ziziphus jujuba Mill. cv. Linyilizao). After that, some QTLs of figure traits and needle length traits were located on the molecular genetic map by using interval mapping. These work will do great help to fine mapping for QTL, mapping based cloning and marker-assisted selection. The main results were as follows:1 .By using 22 RAPD primiers and 8 primiers combinations of AFLP, the research obtained 41 RAPD markers and 51 AFLP markers. In average, every RAPD primier amplified 1.9 polymorphic bands, and each AFLP primiers combination produced 6.4 polymophic bands. The polymorphism detected by AFLP is significant higher, it is about 3.5 times of RAPD's2.With 419 AFLP markers from Shen Lian-ying' study and 92 markers of this research, a high density molecular genetic map was constructed by Joinmap3.0, a total of 388 AFLP markers and 35 RAPD markers were mapped to 15 linkage groups, covering a total length of 1309.4cM with an average markers interal of 3.1cM between loci, only 14 gaps that more than 10cM were found in the map.3.34 QTLs affecting 4 traits of figure were identified in F1 population with MapQTL4.0 software using interval mapping method, 6 QTLs for trunk diameter, 14 QTLs for branch angle, 7 QTLs for branch crankle angle and 7 QTLs for branch bent angle. Some QTLs for branch bent angle were closely linked with the QTLs for the 3 other figure traits according to the traits relativity. Every one of the QTLs affecting 4 traits of figure could explain 8.6%~ 54.2% variation in the traits.4.The putative QTLs were identified controlling needle length, including trunk longneedle length, trunk short needle length, branch long needle length and branch short needle length. 10 QTLs in 6 different linkage groups were found to control the trunk long needle length, 5 QTLs in 3 different groups control trunk short needle length and 9 QTLs for branch long needle length and 2 QTLs for branch short needle length. All the QTLs LOD were varied between 2.51 and 5.27, individual QTL accounted for 8.2%~44.2% variation in the traits. Several QTLs control different traits were mapped in the same loci of the genetic map indicated these traits could be controlled by the same gene.