Pissard A, Ghislain M, Bertin P
Université catholique de Louvain, département de Biologie appliquée et Productions agricoles, Ecologie des Grandes Cultures, Louvain-La-Neuve, Belgium.
Genome. 2006 Jan;49(1):8-16. doi: 10.1139/g05-084.
The Andean tuber-bearing species, Oxalis tuberosa Mol., is a vegetatively propagated crop cultivated in the uplands of the Andes. Its genetic diversity was investigated in the present study using the inter-simple sequence repeat (ISSR) technique. Thirty-two accessions originating from South America (Argentina, Bolivia, Chile, and Peru) and maintained in vitro were chosen to represent the ecogeographic diversity of its cultivation area. Twenty-two primers were tested and 9 were selected according to fingerprinting quality and reproducibility. Genetic diversity analysis was performed with 90 markers. Jaccard's genetic distance between accessions ranged from 0 to 0.49 with an average of 0.28 +/- 0.08 (mean +/- SD). Dendrogram (UPGMA (unweighted pair-group method with arithmetic averaging)) and factorial correspondence analysis (FCA) showed that the genetic structure was influenced by the collection site. The two most distant clusters contained all of the Peruvian accessions, one from Bolivia, none from Argentina or Chile. Analysis by country revealed that Peru presented the greatest genetic distances from the other countries and possessed the highest intra-country genetic distance (0.30 +/- 0.08). This suggests that the Peruvian oca accessions form a distinct genetic group. The relatively low level of genetic diversity in the oca species may be related to its predominating reproduction strategy, i.e., vegetative propagation. The extent and structure of the genetic diversity of the species detailed here should help the establishment of conservation strategies.
安第斯块茎类物种，块茎酢浆草（Oxalis tuberosa Mol.），是一种在安第斯高地种植的无性繁殖作物。在本研究中，采用简单序列重复区间（ISSR）技术对其遗传多样性进行了调查。选择了32份来自南美洲（阿根廷、玻利维亚、智利和秘鲁）并在试管中保存的种质，以代表其种植区域的生态地理多样性。测试了22种引物，并根据指纹质量和可重复性选择了9种。用90个标记进行了遗传多样性分析。种质间的杰卡德遗传距离在0至0.49之间，平均为0.28±0.08（平均值±标准差）。聚类图（非加权算术平均法（UPGMA））和因子对应分析（FCA）表明，遗传结构受采集地点的影响。两个距离最远的聚类包含了所有秘鲁种质、一份来自玻利维亚的种质，没有来自阿根廷或智利的种质。按国家分析表明，秘鲁与其他国家的遗传距离最大，国内遗传距离最高（0.30±0.08）。这表明秘鲁的块茎酢浆草种质形成了一个独特的遗传群体。块茎酢浆草物种相对较低的遗传多样性水平可能与其主要的繁殖策略，即无性繁殖有关。此处详细描述的该物种遗传多样性的程度和结构应有助于制定保护策略。
