Ovando-Medina I, Espinosa-García F J, Núñez-Farfán J, Salvador-Figueroa M
Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Distrito Federal, Mexico.
J Oleo Sci. 2011;60(6):301-11. doi: 10.5650/jos.60.301.
The genetic diversity of Mesoamerican populations of the biofuel plant Jatropha curcas, using the fatty acids of the seeds as chemical markers was studied. The oil content of the whole seed in 135 accessions from 38 sites varied between 8.020% and 54.28%. The prevalent fatty acids were oleic acid (18:1) and linoleic acid (18:2), and the proportion of unsaturated fatty acids varied between 74.5% and 83.7%. A study with cloned plants grown in common garden showed that both the content of oil as well as the proportion of fatty acids are highly inheritable, therefore these chemical markers are valid for estimating the genetic diversity of the species. An analysis of principal components showed that the fatty acids that contribute more to the variance are stearic, oleic, linoleic, methylpalmitic, gadoleic and ricinoleic. The populations were classified in ten groups when the data were analyzed for fatty acids by analysis of clusters, showing the elevated genetic variation in natural populations of this native species of Mesoamerica. A discriminant analysis separated the populations in accordance with their geographic origin, which was verified with a Mantel test. Using the Monmonier's algorithm two genetic barriers between the populations were identified. The results are discussed in light of their microevolutionary significance.
利用种子脂肪酸作为化学标记，对生物燃料植物麻疯树中美洲种群的遗传多样性进行了研究。来自38个地点的135份种质的全种子含油率在8.020%至54.28%之间。主要脂肪酸为油酸（18:1）和亚油酸（18:2），不饱和脂肪酸比例在74.5%至83.7%之间。一项对在共同园地里种植的克隆植物的研究表明，油含量和脂肪酸比例都具有高度遗传性，因此这些化学标记对于评估该物种的遗传多样性是有效的。主成分分析表明，对变异贡献较大的脂肪酸是硬脂酸、油酸、亚油酸、甲基棕榈酸、二十碳烯酸和蓖麻油酸。通过聚类分析对脂肪酸数据进行分析时，种群被分为十组，表明这种中美洲本土物种的自然种群具有较高的遗传变异。判别分析根据种群的地理起源对其进行了区分，这通过曼特尔检验得到了验证。使用蒙莫尼尔算法确定了种群之间的两个遗传屏障。根据其微进化意义对结果进行了讨论。
