Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, SP Brazil.
Genet Mol Biol. 2009 Jan;32(1):104-10. doi: 10.1590/S1415-47572009005000010. Epub 2009 Jan 17.
Based on nine microsatellite loci, the aim of this study was to appraise the genetic diversity of 42 cassava (Manihot esculenta) landraces from selected regions in Brazil, and examine how this variety is distributed according to origin in several municipalities in the states of Minas Gerais, São Paulo, Mato Grosso do Sul, Amazonas and Mato Grosso. High diversity values were found among the five above-mentioned regions, with 3.3 alleles per locus on an average, a high percentage of polymorphic loci varying from 88.8% to 100%, an average of 0.265 for observed heterozygosity and 0.570 for gene diversity. Most genetic diversity was concentrated within the regions themselves (H(S) = 0.52). Cluster analysis and principal component based scatter plotting showed greater similarity among landraces from São Paulo, Mato Grosso do Sul and Amazonas, whereas those from Minas Gerais were clustered into a sub-group within this group. The plants from Mato Grosso, mostly collected in the municipality of General Carneiro, provided the highest differentiation. The migration of human populations is one among the possible reasons for this closer resemblance or greater disparity among plants from the various regions.
本研究基于 9 个微卫星位点，旨在评估来自巴西选定地区的 42 份木薯（Manihot esculenta）地方品种的遗传多样性，并研究这种多样性根据起源在米纳斯吉拉斯州、圣保罗州、南马托格罗索州、亚马孙州和马托格罗索州的几个城市是如何分布的。上述五个地区的多样性值都很高，平均每个位点有 3.3 个等位基因，多态性位点的百分比从 88.8%到 100%不等，观察杂合度的平均值为 0.265，基因多样性的平均值为 0.570。大多数遗传多样性集中在各地区内部（H(S) = 0.52）。聚类分析和基于主成分的散点图表明，来自圣保罗州、南马托格罗索州和亚马孙州的地方品种之间更为相似，而来自米纳斯吉拉斯州的地方品种则在这个组内形成一个亚组。来自马托格罗索州的植物，主要来自卡内罗将军市，其分化程度最高。人口迁移是导致各地区植物之间更相似或更大差异的可能原因之一。
