Construction Of A Genetic Linkage Map Of Peanut With SSR Markers And SRAP Markers

Peanut is an important oil and industrial crop in our country, and plays a decisive pole in agricultural production and national economy. Growing up of DNA molecular marker breathe new life into the peanut reasearch., The use of the high and new technology in peanut is still little comparing with other crops. The molecular markers used in peanut before are RFLP and RAPD, the development of AFLP ,DAF, SSR, SRAP molecular marker provides more methods for DNA polymorphism research of peanut. Such progress has been maked in linkage map construction of peanut at the same time, and some linkage maps had been constructed, but these linkage maps were constructed base on wild species mainly, great difficulty exists in research of some important economical character and economic character of peanut cultivated species with these linkage maps. Therefore it is necessary of the construction of population based on peanut cultivated species for construction of linkage map. Linkage map for the peanut cultivated species were constructed by SSR molecular marker and SRAP molecular marker and genetic linkage rule of the gene for pink color in peanut was analyzed by SSR markers in this study.The results were as follows:Linkage map primary construction of peanut by SSR marker:SSR marker was used to detect the polymorphisms between "Yueyou7" and "Liuyuexue", 25 polymprphic markers after x’detected were used to screen the population and constructed the linkage map by Mapmaker/EXP version 3.0 software. Linkage analysis analysised with linkage(LOD≥3.0) showed that 23 loci mapped into 4 linkage groups. This linkage map was 569.5cM with an average distance of 24.7cM. There were 2～7 loci in each linkage group, and the linkage group distance ranged from 25.5 cM to～199.8cM. All the markers distributed evenly among the linkage groups without clustering of loci.Genetic linkage analysis of SSR markers and the gene for pink color in peanut:Genetic linkage rule of SSR markers and the gene for pink color in peanut was analyzed with the populations derived from combination of Yueyou7 (pink) and Liuyuexue (white). The results showed that the pink color in peanut was possibly controlled by an completed dominant major gene. The gene for pink color was linked with the SSR marker PMX121, and the genetic distance is about 36cM.Linkage map primary construction of peanut by SRAP marker:SRAP marker was used to detect the polymorphisms between "Yueyou7" and"Liuyuexue", which showed comparatively high polymorphisms, every primer combination producing about 10～30 clearly discriminable bands. 35 primer combinations with higher polymorphisms were used to screen the population, and generated 112 polymorphic bands in total with an average of 3.2 polymorphic bands perprimer pair. One primer combinations generated 1～5 polymorphic bands. 95 polymprphic markers after x’detected were analysis, then constructed the linkage map. Linkage analysis analysised with linkage(LOD≥3.0) showed that 77 loci mapped into 11 linkage groups. This linkage map was 1661.2cM with an average distance of 21.5cM.There were 2～7 loci in each linkage group and the linkage group distance ranged from 91 cM to 195.7 cM. All the markers distributed evenly among the linkage groups without clustering of loci.