Heredity diversity in populations of free-, self-, and specific cross-pollinated progenies of some olive (<i>Olea europaea</i> L.) cultivars

Abstract

The genetic diversity within most olive seedling populations is extremely high. Although the heredity of some traits was found dominant in controlled crossings, the diversity within each progeny remained high. Cross-pollination is essential in most years and under most growing conditions for satisfactory fruit set; however, self-pollination can also result in fruit set with viable seeds. The present study aimed to determine the degree and type of genetic diversity in progenies from free-, self-, and controlled cross-pollinated olive trees. The data presented are based on progenies of 200-500 trees from each cultivar and treatment grown in breeding plots at Bet Dagan. Tree vigor, shape, leaf morphology, and fruit characteristics were determined. The level of variation of each character from the mother cultivar was calculated for each progeny. The level of distribution of characters in the progeny plants of free and self-pollination was rather similar except for fruit fresh weight. A dominant female heredity of tree size, leaf and fruit form, as well as oil content was found for specific mother cultivars. This, however, had no significant effect on the degree of diversity within each progeny, which might be a result of varying amounts of self-pollination in each treatment.