Analysis Of Genetic Variation In Eggplant Using Morphological And ISSR,SSR Makers

Eggplant(Solanum melongena L.)originated in tropics areas of south Asian,and was firstly domesticated in the region of ancient Indian. China has a long history of cultivating eggplant and are rich in germplasm resources,which was recognized as secondary origin center of eggplant.The reserach on the genetic diversity of eggplant germplasm resources was of great benefit to the conservation,classification,identification, innovation and effective utilization of eggplant germplasms.Currently,with the development of molecular marker biotechnology,it has widely used in taxonomy of plants.To evaluate the level of genetic diversity and phylogenetic relationship among 76 eggplant germplasm,which contains foreign several varieties and wild species,morphological markers,ISSR(Inter-simple sequence repeat) and SSR(Simple Sequence Repeat) molecular markers were carried out in this paper. The main results are as follows:l.The 28 morphological characteristics were assigned and investigated. The results showed that there were significant genetic difference in all of the phenotypic traits.The variation coefficient was largest for leaf prickle(493.3%),and smallest for curvature of fruit(10.9%);13 characters of the fruit were divided into four components by the factor analysis;Choosing 19.5 as threshold value of cluster analysis,76 eggplant materials were divided into 7 groups.2.The ISSR-PCR system was optimized based on the single factor and orthogonal experiments.20μL PCR system was as follows:1×buffer,2.62mmol/L Mg2+,1.88mmol/L dNTP, 50ng template DNA,1 U Taq DNA polymerase,0.5μmol/L primer.10μL SSR-PCR system has the same concentration of components with ISSR-PCR system.3.10 high-polymorphism ISSR primers were screened out of 40 ISSR primers,and 10 from 30 SSR primers. Temperature gradient method was used to identify the optimal annealing temperature.There were 59 polymorphic locus amplified by ISSR primer,and 45 by SSR primer.4.The amplification results of ISSR and SSR molecular markers on 76 eggplant germplasm materials were analysed by NTSYsPc-2.1, and genetic relationship clustering tree was formed by UPGMA method. All of the76 eggplant were divided into 7 groups by ISSR molecular marker, and 6 groups by SSR molecular marker. 5. The clustering analysis of the mergered statistics between ISSR and SSR marker showed that the similarity coefficient of 76 eggplant germplasms were between 0.65 and 0.96,on the similarity coefficient level of 0.79 when all the tested materials were divided into 6 clusters. The consistency test showed that the clustering results of SSR molecular markers were more similar to the combined clustering results.