Centro de Investigación Científica de Yucatán, Apartado Postal 87, Cordemex, Mérida, Yucatán, México 97310; and.
Am J Bot. 1999 Jan;86(1):115-23.
Isozymatic variation and phylogenetic relationships among extant henequén (Agave fourcroydes) germplasm and wild populations of its ancestor A. angustifolia in the Yucatan Peninsula in Mexico were analyzed. Analysis of three isozyme systems using starch gel electrophoresis indicated that while A. angustifolia populations have relatively high levels of variation, within each henequén cultivar all individuals were identical. This result corresponds to previous ethnobotanical and morphological analyses, which indicated severe loss of genetic variation of this domesticated plant as a consequence of the promotion by means of asexual propagation of only one cultivar since the middle of the last century. The three extant cultivars of henequén were distinct from each other. Two of them, Sac Ki (SK) and Yaax Ki (YK), could be matched within the progenitor, but Kitam Ki (KK) has a MDH electrophenotype not found in any of the plants growing inside the Yucatan Peninsula, but found in some A. angustifolia plants growing in the Mexican states of Oaxaca and Veracruz. A parsimony analysis of the morphological data indicated two lineages: that of SK and YK, cultivated cordage plants selected for stronger and longer fibers, whose sister group is the Tropical subdeciduous forest ecotype (SF), and that of all the other wild populations, which also included KK, the cultivated textile plants selected for finer fibers and nearly extinct in Yucatan. These results support the hypothesis of the yucatecan origin of SK and YK from the SF ecotype, as well as the hypothesis of a recent introduction of KK to the Yucatan Peninsula in a domestication trend that probably included also Chelem White (its cultivation being abandoned later).
对存在于墨西哥尤卡坦半岛的龙舌兰麻（Agave fourcroydes）种质资源及其野生祖先 A. angustifolia 的同工酶变异和系统发育关系进行了分析。利用淀粉凝胶电泳分析了三个同工酶系统，结果表明，虽然 A. angustifolia 种群具有相对较高的变异水平，但在每个龙舌兰麻品种中，所有个体都是相同的。这一结果与之前的民族植物学和形态学分析相吻合，这些分析表明，由于上个世纪中叶以来只通过无性繁殖推广了一个品种，这种驯化植物的遗传变异严重丧失。现存的三个龙舌兰麻品种彼此不同。其中两个，Sac Ki（SK）和 Yaax Ki（YK），可以与祖先匹配，但 Kitam Ki（KK）的 MDH 电泳表型在尤卡坦半岛内生长的任何植物中都没有发现，但在墨西哥瓦哈卡州和韦拉克鲁斯州生长的一些 A. angustifolia 植物中发现。对形态数据的简约分析表明存在两个谱系：SK 和 YK 的谱系，它们是为了更强壮和更长的纤维而选择的绳索植物，其姐妹群是热带半落叶森林生态型（SF），以及其他所有野生种群的谱系，其中还包括 KK，它们是为了更细的纤维而选择的纺织植物，在尤卡坦几乎灭绝。这些结果支持了 SK 和 YK 源自 SF 生态型的假设，以及 KK 最近被引入尤卡坦半岛的假设，这种驯化趋势可能还包括 Chelem White（后来停止了其种植）。
