Effects Of Temperature And Precipitation On Genetic Differentiation And Distribution Pattern Of Salix Psammophila

The correlation between the genetic diversity of 21 Salix psammophila populations and environmental factors is to explore the driving force of genetic differentiation,to better understand the ecological adaptability,and to fully grasp the national germplasm resources of the populations.It provides theoretical basis for the genetic variation law of the library,the management of the germplasm resource storage library and the selective breeding of excellent varieties.22 pairs of EST-SSR primers was used to detect the genetic diversity of four populations which were grown in the S.psammophila germplasm resource bank.Based on the results of previous studies(17 populations),we analysed the genetic diversity of S.psammophila.The correlation between genetic parameters and climatic factor was tested.The results showed that the genetic variation within population was 94%and among population was only 6%.The genetic distance of the population was significantly related to the geographic distance(r=0.46 P=0.001).The analysis of variance of climate factors at 30a showed that the average temperature differences between April,May,and June were significant,and the average precipitation was not significant(P=0.05).Correlation analysis of genetic diversity parameters and climate factors showed that the average temperature of May,June and genetic diversity parameters(PIC,He)were significantly correlated.Geographic-climatic factors jointly affect the genetic diversity of S.psammophila.Based on the MaxEnt model,the current distribution pattern of Salix psammophila(AUC≥0.9)is simulated.Temperature seasonality,Precipitation of wettest month,Mean annual temperature have the highest contribution rates,respectively 30.1%,21%,and 6%.The area of the suitable area under the four scenarios(RCP2.6,RCP4.5,RCP6.0,RCP8.5)from the current period to the future(2050)period has increased,then discuss the current and future distribution pattern of S.psammophila in China.It can be seen from the prediction results that the suitable habitat of Salix psammophila accounts for a small proportion of the total area of China,showing that the growth area of Salix psammophila is relatively narrow.