A Preliminary Study On Genetic Diversity And Rapid Propagation System Of Lycium Ruthenicum

Lycium ruthenicum Murr.,a perennial deciduous shrub of the genus Lycium in Solanaceae,is mainly distributed in northwest China.Its fruit is rich in anthocyanin,polysaccharide,mineral and other nutrients,known as a natural antioxidant.Lycium ruthenicum Murr.not only has medicinal value and health care value,but also has great ecological value as a pioneer tree for desertification control in northwest China.In recent years,due to the deterioration of the growth environment,the low seed germination rate under natural conditions and people's destructive picking,the resources of Lycium ruthenicum Murr.have been largely destroyed.At present,Lycium ruthenicum Murr.has been cultivated artificially,but the research on seed selection and propagation and directional cultivation technology need to be further strengthened.In this study,SSR molecular marker technology was used to study the genetic diversity and population differentiation of Lycium ruthenicum Murr.germplasm resources in northwest China,and the in vitro rapid propagation system of Lycium ruthenicum Murr.was established,providing theoretical basis and technical support for the protection and utilization of Lycium ruthenicum Murr.resources in China as well as the breeding and propagation of new varieties.The main results were as follows:1.Using transcriptomic data,20 pairs of SSR primers with good polymorphism and clear bands were developed and selected for genetic diversity and genetic relationship analysis of germplasm resources of Lycium ruthenicum Murr.,and the SSR-PCR amplification system was optimized.2.All primers can be amplified effectively in the samples of Lycium ruthenicum Murr.,which can be used in the genetic diversity study of Lycium ruthenicum Murr.Among them,the main genetic diversity indexes of the populations of Lycium ruthenicum Murr.based on SSR markers were: the average allele was 1.66,the average number of effective alleles was 1.36,the average Nei's genetic diversity index was 0.21,Shannon index was 0.31,and the average observed heterozygosity(Ho)was 0.30.The expected heterozygosity(He)was 0.23 on average.The genetic diversity index of SSR molecular markers in the germplasm resources of Lycium ruthenicum Murr.indicated that the genetic diversity of Lycium ruthenicum Murr.was relatively low.3.The results of AMOVA analysis showed that the genetic variation of Lycium ruthenicum Murr.mainly came from the internal population,and there was moderate genetic differentiation among the populations,and the gene flow(Nm)between the populations was 0.5026,indicating that there was certain gene communication between the populations of Lycium ruthenicum Murr.4.Mantel was used to test the relationship between the geographical distance and the genetic distance matrix of various populations of Lycium ruthenicum Murr.,and the results showed a low correlation(r2=0.037,P = 0.250),indicating that the genetic characteristics of different populations were not significantly affected by the geographical distance isolation,the BOTTLENECK of software analysis Wilcoxon signed rank test results show that the black fruit of Chinese wolfberry three clustered in two models of genetic BOTTLENECK IAM and TPM were excessive hybrid obviously(P<0.01)and significant genetic BOTTLENECK effect(P<0.01),the model transformation test results also showed that the displacement mode,this shows that the population genetic distribution of Lycium ruthenicum Murr.was likely to be influenced by genetic bottlenecks.5.The technique system of rapid propagation of fructus lycii was as follows: the optimal medium formula for callus induction using sterile vaccine as culture material was MS+6-BA(1.0mg/L)+NAA(0.5mg/L),and the callus growth was the best,with the recovery rate of 95%.The optimal medium formula for inducing adventitious buds was MS+ 6-BA(0.2mg/L),and the multiplication coefficient of adventitious buds was 5.6.The best effect was to induce adventitious buds to multiply into fascicled buds by MS+6-BA(0.2mg/L)+NAA(0.05mg/L).The optimal medium formula was determined to be 1/2 MS+ IBA(0.2mg/L),and the rooting rate was 80%.