应用AFLP技术分析冬枣优良单株选择的遗传基础

Analysis of Genetic Background for the Selection of Advanced Trees of Dongzao(Zizyphus jujuba Mill.cv.Dongzao)by AFLP Markers

为探讨冬枣优良单株选择的遗传基础,本研究收集了河北、山东冬枣优良单株及对照冬枣共52株,以金丝小枣和尖枣做类外对照进行AFLP分子标记研究。实验选用16对M/E引物组合,共扩增出565条带,基于SM相似系数,利用UPGMA法对多态性谱带进行聚类分析,结果表明:冬枣优良单株群体内存在一定的遗传差异,但这种差异小于冬枣与金丝小枣和尖枣间的遗传距离,因此在聚类图中将冬枣、金丝小枣和尖枣分为3类;冬枣优良单株群体在聚类图中分成若干组,其中河北黄骅原始冬枣林古树和源于原始冬枣林的黄骅采穗圃冬枣优良单株,遗传距离相对较远;山东滨州各县的冬枣优良单株和沾化冬枣古树遗传距离较近,但存在个别变异较大的单株。上述结果证实冬枣是一个存在变异的群体、包含不同类型的品系,不同来源的冬枣优良单株存在一定的遗传变异,说明冬枣优良单株的优良性状不完全是立地条件和栽培技术引起的环境饰变,这一研究结果为冬枣的遗传改良和品种内选优提供了理论依据。

This study analyzed genetic background of 52 advanced Dongzao（Zizyphus jujuba Mill. cv. Dongzao） trees and their control,Jinsixiaozao and Jianzao cuhivars from Hebei and Shandong provinces using amplified fragment length polymorphism（AFLP） markers with 16 pair of Mse I/EcoR I primer combinations. Cluster analysis was performed by using of unweighted pair group method with arithmatic mean （UPGMA） method based on SM similarity coefficient. The results were as follows： a total of 565 bands were amplified by 16 primer pairs,of which,225 were the polymorphic bands including Jinsixiaozao and Jianzao cuhivars,99 were the polymorphic bands among Dongzao advanced trees. There was a little difference among the group of Dongzao advanced trees （ the average similarity coef- ficient was 0. 9792）,though the difference was smaller than the difference between Dongzao with Jinsixiaozao and Jianzao cultivars（ the similarity coefficient were 0. 8294 and 0. 7977, respectively）. The three cuhivars were divided into 3 groups and the group of Dongzao advanced trees were divided into several part in the cluster analyzing map. The genetic distance of the old Dongzao trees and the Dongzao advanced trees from Huanghua county,Hebei province were bigger than the ones from Binzhou city, Shandong province, the similarity coefficient were 0. 9649 and 0. 9946,respectively. But there were some individual candidate of aberrance among the latter. The above-mentioned results showed that there were some variation among Dongzao cultivar and the eximious traits of the advanced trees were not all attributed to the different growth condition and cultivating methods. So the resuhs were very helpful to the genetic improvement and the selection of advanced trees of Dongzao cuhivar.