High levels of genetic variation in populations of four dominant aridland plant species in Arizona
High levels of genetic variation in populations of four dominant aridland plant species in Arizona
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亚利桑那州四种主要干旱植物物种种群的高水平遗传变异
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
J. Ehleringer
中科院分区：
文献类型：
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作者：
W. Schuster;D. Sandquist;S. Phillips;J. Ehleringer
摘要利用同工酶技术对北美西南部沙漠地区四种主要多年生植物种群内的遗传变异进行了评估和比较。在两个地方，一个温暖的沙漠和一个寒冷的沙漠环境中，一个最常见的长寿多年生植物的人口进行了比较，附近的人口占主导地位，相对短命的多年生植物。暖性荒漠种为Encelia farinosa和Larrea tridentata，冷性荒漠种为Gutierrezia microcephala和Coleogyne ramosissima。对所有样品进行18种酶系统的重复测定和染色。这四个物种的平均值为0.173的基因多样性，66.9%的多态性，和2.02的等位基因数每个位点。这些值是显着大于发表的植物同工酶文献的最近调查的手段，并相当于或高于其他广泛分布的植物物种的遗传变异水平。物种之间的变异水平差异并不显著，因此未能表明预期寿命与遗传变异之间的任何关系。这些结果表明，干旱地区植物种群可以具有高水平的遗传变异，并表明环境异质性可能对这种多样性的发展和维持很重要。
Abstract Intrapopulation genetic variation in four dominant, perennial plant species from the deserts of south-western North America was assessed and compared using isozyme techniques. In each of two localities, a warm desert and a cold desert environment, one population of the most common long-lived perennial was compared with a nearby population of a dominant, comparatively short-lived perennial. The warm desert species were Encelia farinosa and Larrea tridentata while Gutierrezia microcephala and Coleogyne ramosissima were examined at the cold desert site. All samples were electrophoresed and stained for 18 enzyme systems. Mean values for these four species were 0·173 for gene diversity, 66·9% for polymorphism, and 2·02 for number of alleles per locus. These values are significantly greater than published means from a recent survey of the plant isozyme literature, and are comparable to or higher than levels of genetic variation in other widespread plant species. Differences in level of variation among the species were not significant, thus failing to indicate any relationship between life expectancy and genetic variation. These results demonstrate that aridland plant populations can harbor high levels of genetic variation, and suggest that environmental heterogeneity may be important in the development and maintenance of this diversity.