Spanish melons (Cucumis melo L.) of the Madrid provenance: a unique germplasm reservoir

作者：Escribano Sandra; Lazaro Almudena^*; Cuevas Hugo E; Lopez Sese Ana I; Staub Jack E

来源：Genetic Resources and Crop Evolution, 2012, 59(3): 359-373.

DOI：10.1007/s10722-011-9687-4

• Cucumis melo
• Exotic germplasm
• Genetic distance
• Market class
• Molecular markers
• SSRs

Melon (Cucumis melo L.) landraces of the Madrid provenance, Spain, have received national distinction for their high fruit quality and sensorial attributes. More specifically, a unique array of Group Inodorus landraces have been continuously cultivated and conserved by farmers in the municipality of Villaconejos since the 19th century. Their genetic relationships to other Group Inodorus and Flexuous melon market classes is not known, and, thus, a study was designed to determine their genetic relationships using 52 simple sequence repeat (SSR) markers, and then make genetic comparisons between these accessions and a previously published %26quot;Standard Reference Germplasm Array%26quot; (RA) containing Group Inodorus (14 Spanish and one USA), Flexuosus (1 Spanish), and Cantalupensis ( 2 USA) melon accessions. This subset consisted of 15 Spanish Group Inodorus landraces that circumscribed the genetic variation of major Spanish melon market classes (Groups Inodorus and Flexuosus), and USA commercial varieties (Groups Cantalupensis and Inodorus). Based on genetic distances, Villaconejos (Madrid) genotypes differed substantially from RA subset accessions, thus defining their genetic uniqueness. Principal component analysis (PCA) partitioned the accessions examined into four distinct groups revealing that Villaconejos black epidermis melons (landraces %26apos;Largo%26apos;, %26apos;Largo Negro Escrito%26apos; and %26apos;Puchero%26apos;) were distinctly different from all other accessions examined, as cluster analysis separated Rochet market type Villaconejos%26apos; accessions (landraces %26apos;Mochuelo%26apos;, %26apos;Mochuelo Tradicional%26apos; and %26apos;Meln de Villaconejos%26apos;) from RA of the same market type. Genetic assessment of principal Spanish market classes revealed comparatively low intra-market heterogeneity in Piel de Sapo type accessions and high heterogeneity in Black and Yellow market type accessions. While a relatively high level of genetic introgression was detected between Yellow and Green market types, black epidermis market types were genetically unique. Given the uniqueness and high genetic diversity resident in Villaconejos landraces, this germplasm pool should be considered as a genetic source for broadening the comparatively narrow genetic base of Group Cantalupensis and Inodorus melon market types, especially standard commercial Spanish Group Inodorus market types (e.g., Piel de Sapo, Rochet, and Canari).

• 出版日期2012-3