Morphological and molecular diversity of a collection of Cucurbita maxima landraces
Morphological and molecular diversity of a collection of Cucurbita maxima landraces
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DOI：
10.21273/jashs.129.1.0060
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发表时间：
2004-01-01
影响因子：
1.9
通讯作者：
Nuez, F
中科院分区：
文献类型：
--
作者：
Ferriol, M;Picó, B;Nuez, F
南瓜是形态上最易变的栽培种之一。农业多样性保护和育种中心（COMAV）拥有南瓜属的多样化种质资源，该物种有300多个地方品种。需要形态学和分子表征以便于农民和育种者使用该收集物。为此，对120株C.评价了极大属种质。大多数这些加入来自西班牙，它已作为一个桥梁，自16世纪世纪以来，传播西葫芦形态类型之间的美洲和欧洲。南美洲的地方品种（该物种的起源中心）也包括在内。根据这一特征和以前的种内分类建立了8个形态类型。这些加入，从这些分类和护照数据中选择的一个子集，用于分子表征。使用了两种标记类型;序列相关扩增多态性（SRAP）和扩增片段长度多态性（AFLP），SRAP优先扩增开放阅读框（ORF）。SRAP标记分析主要根据其使用类型（农艺性状）对加入物进行分组，AFLP标记分析则根据其地理来源对加入物进行分组。AFLP标记分析发现，更大的遗传变异之间的美国比西班牙加入。这可能是由于在将南瓜引入欧洲期间可能发生的遗传瓶颈。用两种标记获得的结果的差异可能与不同的基因组覆盖度有关，这是每种特定标记类型的特征和/或与其在群体中取样变异的效率有关。
Cucurbita maxima Duch. is one of the most morphologically variable cultivated species. The Center for Conservation and Breeding of the Agricultural Diversity (COMAV) holds a diverse germplasm collection of the Cucurbita genus, with more than 300 landraces of this species. Morphological and molecular characterization are needed to facilitate farmer and breeder use of this collection. With this aim, the morphological variation of a collection of 120 C. maxima accessions was evaluated. The majority of these accessions originated from Spain, which has acted as a bridge since the 16th century for spreading squash morphotypes between the Americas and Europe. South American landraces (the center of origin of this species) were also included. Eight morphological types were established based on this characterization and previous intraspecific classifications. A subset of these accessions, selected from these classification and passport data, was employed for molecular characterization. Two marker types were used; sequence related amplified polymorphism (SRAP), which preferentially amplifies open reading frames (ORF), and amplified fragment length polymorphism (AFLP). In the main, SRAP marker analysis grouped accessions in accordance to their type of use (agronomic traits) and AFLP marker analysis grouped accessions as to their geographical origin. AFLP marker analysis detected a greater genetic variability among American than among Spanish accessions. This is likely due to a genetic bottleneck that may have occurred during the introduction of squash into Europe. The disparity of the results obtained with the two markers may be related to the different genome coverage which is characteristic of each particular marker type and/or to its efficiency in sampling variation in a population.