利用内含子切接点引物分析西藏青稞种质资源的遗传多样性

Assessment of Genetic Diversity of Tibetan Hulless Barley Germplasm (Hordeum vulgare L.) by ISJ Primers

采用26条内含子切接点引物（ISJ）,对50份来自藏区的青稞育成品种、50份西藏近缘野生大麦、44份西藏青稞地方品种,共144份供试材料的遗传多样性进行了分析.结果分析表明,筛选利用22对多态较好的引物或引物组合对实验材料进行扩增,不同引物或引物组合扩增条带数变幅为3～12.144份材料间GS值变化变幅为0.06 ～0.96之间;群体内的平均GS大小顺序依次为,西藏青稞地方品种＞西藏近缘野生大麦＞藏区青稞育成品种;遗传多样性分析顺序依次为西藏近缘野生大麦（1.5964）＞藏区青稞育成品种（1.5841）＞西藏青稞地方品种（1.1657）.对统计条带并建立[1,0]矩阵,聚类与主坐标分析表明,以144份材料的GS值0.40 （L）为阈值,可将其划分为七类.研究结果表明,同一来源地区的青稞育成品种遗传基础较为狭窄,而不同地区间的藏区青稞育成品种遗传差异较大;在进行青稞超高产新品种选育时,应充分发掘西藏近缘野生大麦和利用不同地域来源的育成品种,加强不同地区间资源的交换,以利于增加群体材料的遗传多样性和新品种的培育.

In order to assess the rich Tibetan Hulless barley germplasm in Tibet, we analyzed the genetic diversity of 144 Hulless barley varieties, including 50 Tibetan bred barley materials, 50 wild relatives of barley materials, and 44 Tibet highland barley landrace varieties by 26 introns splice junction （ ISJ ） primers. The results showed that there were 22 primers with high polymorphism out of 26 ISJ primers, bands ranged from 3 to 12 and the GS values ranged from 0. 06 to 0. 96 among the 144 materials. The average size of GS sequence in different population of hulless barleys was Tibet highland barley landrace varieties 〉 wild relatives barley 〉 Tibetan bred barley. The results of those analyses on the genetic diversity indicated that wild relatives of barley varieties （ 1. 5964） 〉 Tibetan bred barley （ 1. 5841 ） 〉 Tibet highland barley landrace varieties （ 1. 1657 ） . Clustering and main coordinate analysis showed that when the threshold value GS = 0. 40, experimental materials were divided into 7 big groups by establishing matrix [ 0, 1 ] . The results showed that Tibetan bred barley with the same source area were narrow genetic basis, otherwise Tibetan bred barley with the different source area were genetic difference; in our future barley breeding work, it is necessary to explore the wild relatives of barley resource and the different geographical origin of bred barley varieties. Strengthen the exchange among resources, and increase the genetic diversity of breeding materials and new varieties.