IDENTIFYING MOLECULAR-GENETIC MARKERS ASSOCIATED WITH SEEDLESSNESS INGRAPE

Excluding seeded offspring at an early stage could be of great value t o the breeder concerned with the development of seedless grapes (Vitis vinifera L.). We used the random amplified polymorphic DNA (RAPD) tec hnique to identify molecular genetic markers, analyzing 82 individuals of a progeny resulting from a cross between 'Early Muscat' (seeded) a nd 'Flame Seedless', Seven variables representing the traits of seedle ssness were analyzed: mean fresh weight of one seed, total fresh weigh t of seeds per berry, perception of seed content, seed size categories evaluated visually, degree of hardness of the seed coat, degree of de velopment of the endosperm, and degree of development of the embryo. A mong 160 10mer primers, 110 gave distinct band patterns. Twelve marker s yielded significant correlations with several subtraits of seedlessn ess, mainly with the mean fresh weight of one seed and the total fresh weight of seeds per berry, Multiple linear regression analysis result ed in high coefficients, such as R = 0.779 for fresh weight of seeds p er berry, when the seven markers were included as independent variable s in the model, Most of the seeded individuals, about 44% of the proge ny, could be excluded using a two-step process of marker assisted sele ction.