石榴品种SSR指纹图谱构建及杂种父本鉴定

Construction of SSR Fingerprints of Pomegranate Cultivars and Male Parent Identification of Hybrids

以枣庄市石榴国家林木种质资源库中收集的168个石榴品种为材料,利用SSR分子标记技术构建了石榴品种资源指纹图谱,并基于指纹图谱信息,应用最大似然值法(LOD)对品种‘秋艳’和‘会理青皮软籽’的自然授粉实生苗进行了杂种筛选及父本初步鉴定。22对SSR引物从168个石榴品种样品中共扩增到76个等位标记位点,其中多态性位点58个,多态性为76.3%。平均等位位点数(N_(a))、有效等位位点数(N_(e))、观测杂合度(H_(o))、期望杂合度(H_(e))分别为3.455、2.269、0.362、0.538,Shannon’s信息指数(I)平均值为0.897,多态性信息含量(PIC)介于0.330~0.692之间,平均PIC值为0.462。利用22对SSR引物可将166个石榴品种区分开,另有‘大满天红甜’和‘小满天红甜’2个品种未有效区分,有同物异名的可能;在此基础上构建了166个品种的特异指纹代码及指纹图谱二维码。基于指纹图谱信息,利用SSR标记从‘秋艳’的30个自然授粉子代实生苗中筛选到1个真杂种Q-1,疑似父本为‘峄城丰产马牙’,LOD值为5.96;从‘会理青皮软籽’的118个自然授粉子代实生苗中筛选到6个真杂种H-4、H-49、H-51、H-87、H-94和H-103,疑似父本分别为‘四川黄皮酸’‘突尼斯软籽’‘蒙自红花白皮’‘四川黄皮酸’‘突尼斯软籽’及‘蒙自红花白皮’。

Young leaves of 168 pomegranate cultivars collected from the National Forest Germplasm Resource Repository for Pomegranate,Zaozhuang City,Shandong,China were used to construct their fingerprints using SSR molecular marker technique.Based on the fingerprint information,the maximum likelihood method(LOD)was applied to hybrid screening in open-pollinated progenies of the cultivars‘Qiuyan’and‘Huili Qingpi Ruanzi’and identification of suspected male parent.The results showed that a total of 76 alleles were amplified from 22 pairs of SSR primers in the 168 cultivar samples,including 58 polymorphic loci(accounting for 76.3%).The average number of alleles per locus(N_(a)),effective number of alleles(N_(e)),observed heterozygosity(H_(o))and expected heterozygosity(H_(e))was 3.455,2.269,0.362 and 0.538,respectively.The average Shannon’s information index(I)was 0.897,the polymorphism information content(PIC)of each marker ranged from 0.330 to 0.692,with an average of 0.462.166pomegranate cultivar samples were distinguished by the 22 pairs of SSR primers.However,‘Damantianhongtian’and‘Xiaomantianhongtian’were not effectively distinguished,which might be synonymous.Using the allelic information,a database containing the specific fingerprint code and two-dimensional fingerprint code for each cultivar was constructed.One true hybrid Q-1 was screened from 30 offspring of open-pollinated‘Qiuyan’by using the fingerprint information.Its suspected male parent is‘Yicheng Fengchan Maya’,with the LOD value of 5.96.Six true hybrids,H-4,H-49,H-51,H-87,H-94 and H-103,were screened from 118 offspring of open-pollinated‘Huili Qingpi Ruanzi’.Their suspected male parents were‘Sichuan Huangpisuan’‘Tunisian Ruanzi’‘Mengzi Honghua Baipi’‘Sichuan Huangpisuan’‘Tunisian Ruanzi’and‘Mengzi Honghua Baipi’,respectively.