Genetic Diversity And Fingerprint Of Kengyilia Thoroldiana Revealed By AFLP Analysis

In this study,K.thoroldiana was used as a main material and 4 populations of closely related species,which included K.grandiglumis,K.rigidula,K.laxiflora and K.birsuta,were used as reference.An amplified-fragment-length-polymorphism(AFLP)protocol was optimized for genetic diversity analysis and DNA fingerprint of K.thoroldiana.The results are as follows:The optimal pre-amplification system(25?l)included 1.0?l ligation products,10×PCRBuffer 2.5?l,dNTPs 0.375?l,Mg2+1?l,Taq DNA polymerase 0.5?l,pre-amplification primers(E+A)1?l and(M+C)1.2?l.Also,in the best selective amplification system(25?l),1/20 pre-amplification products was 2.0?l and10×PCRBuffer 2.5?l,dNTPs 0.75?l,Mg2+2?l,Taq DNA polymerase 0.1?l,selective amplification primers(M+CNN)1.5?l and(E+ANN)2.5 ?l.The map of K.thoroldiana,K.grandiglumis and K.laxiflora DNA fingerprint was drawn and ten populations were fingerprinted with AFLP primers to provide reference for distinctness,purity identification and further utilization.A total of 38 selective primer combinations were screened from 216 primer pairs,which included 6core primer pairs with a total of 28 polymorphic bands.AFLP was used for genetic diversity analysis of 12 K.thoroldiana populations and 4 populations of closely related species.A total of 16 populations were analyzed by 38 AFLP selective amplification primers which created 122 polymorphic bands.Genetic identity among 12 K.thoroldiana populations ranged from 0.6837 to 0.8859 and genetic distance ranged from 0.1212 to 0.3802.The majority(57.18%)of the genetic variation resided within 12 K.thoroldiana populations,and the rest(42.82%)existed among these populations.This study shows that cultivation methods,habitats and altitude all have effects on its genetic diversity and clustering among K.thoroldiana populations.