华南地区常规籼稻主栽品种间亲缘系数分析

Analysis of Coefficient of Parentage Among Major Commercial Inbred Indica Rice Cultivars in South China

品种间亲缘系数是研究作物品种间遗传关系和遗传多样性的重要方法.对华南地区不同年代育成的常规籼稻主栽品种的亲缘系数进行了分析.结果显示,近50年来华南地区基于亲缘系数的水稻品种遗传多样性呈"W"型变化,3个高点分别出现在1957年前、1970—1979年和2000—2008年,3个低点分别出现在1957—1969年和1980—1989年.基于亲缘系数的品种聚类结果较直观地反映了近50年来华南地区籼稻品种的遗传关系及其品种演变特点,与该地区不同时期主要围绕着少数几个骨干亲本进行品种改良的特点相吻合.本研究获得的华南地区近50年来水稻品种遗传多样性呈"W"型变化这一结果说明,基于品种间亲缘系数的华南地区品种遗传多样性未经历持续的下降或上升,而是在一定范围内波动.

Coefficient of parentage among crop cultivars is one of major methods for evaluating genetic relationship and genetic diversity among crop cuhivars. Coefficient of parentage was analyzed among the inbred indica rice cultivars which were released in different eras in South China. The result showed that the genetic diversity among the cultivars released in the past 50 years changed as a ＂W＂ shape. Three summits happened in pre-1957, 1970 - 1979, and 2000 - 2008, and two lowest happened in 1957 - 1969 and 1980 - 1989. The result of cultivars clustering analysis based on coefficient of parentage indicated the genetic relationships among the inbred indica rice cuhivars and the characteristics of the cuhivars evolution in South China. It was coincident with the characteristic of the cultivars improvement based on a few core parents in different eras. These indicated that the genetic diversity in the inbred indica rice cultivars changed as coefficient of parentage among inbred indica cultivars in South China and the genetic diversity had not increased or fall continuously in the past 50 years, but fluctuated in a limited range.