Efficacy of Issr and Srap Techniques for Molecular Characterization of Some Cucurbita Genotypes Including Naked (hull-Less) Seed Pumpkin

Abstract

This study was carried out to determine the efficacy of inter simple sequence repeats (ISSR) and sequence-related amplified polymorphism (SRAP) techniques for molecular characterization some Cucurbita genotypes including naked (hull-less) seed pumpkin. Plant material consisted of sixteen genotypes belonging to Cucurbita pepo L., and four genotypes belonging to Cucurbita moschata Duchesne, and four genotypes belonging to Cucurbita maxima Duchesne. A larger part of the Cucurbita pepo genotypes (7 Turkish and 4 foreign) were seed pumpkin and some of them were naked seed types used as appetizer and/or for oil production. Morphological characterization was also done according to UPOV criteria. The sixty bands were obtained by using 8 ISSR primers and all these bands were found polymorphic. In the SRAP study, 8 primer combinations were used, a total of 71 bands were scored and all these bands were polymorphic. In the ISSR analyses, the genetic similarity coefficients varied between 0.07 and 0.96, while in SRAP it was between 0.13 1.0. The correlation coefficient between ISSR and SRAP genetic similarity data was very high (r = 0.947). The genetic variation as measured by ISSR and SRAP markers revealed high diversity among Cucurbita genotypes (H = 0.30, I = 0.46 and 100 % polym.). The genetic diversity among Turkish naked seed pumpkin genotypes (H = 0.09, I = 0.14 and 26.7 % polym.) was only a little less than that of the foreign accessions (H = 0.12, I = 0.18 and 32.1 % polym.). Some differences were observed between molecular and morphological studies, and it was concluded that only morphological or molecular analyses but a combination of both approaches are often more reliable in genetic variability studies in Cucurbita genus.