A STUDY ON THE GENETIC EFFECT AND MAS EXPLORATION OF JUVENILE PHASE AND FRUIT MATURATION PERIOD IN A MAPPING POPULATION OF LITCHI

Important traits including juvenile period, fruit maturation period and duration of fruit development were investigated in the F₁ mapping population of ‘Maguili×Jiaohesanyuehong’ in order to understand the separation patterns and genetic variation tendencies of these traits. The results showed that the juvenile period varied from 4.5 to 8.5 years or more, and there were a lot of individuals with short juvenile phase, suggesting that the juvenile of litchi hybrid seedlings was related with the genotypes. The traits of fruit maturation period and duration of fruit development displayed an intermediate inheritance, but the maternal hereditary potency was a little stronger than the paternal, suggesting a matroclinal inheritance tendency. The fruit maturation period showed a continuous variation and the duration of fruit development showed a typical normal distribution, both displayed a quantitative inheritance pattern. Also, the fruit maturation data proved that it is available to predict the ripening stage of the individuals even in their seedling stage by application of the molecular markers (RAPDs and SCARs) closely related with fruit maturation period, which were obtained in our early experiments. The above results showed that there were abundant individuals with short juvenile period and extremely late maturation among the mapping population, providing perfect materials for QTL location and breeding of new cultivars. The mapping population is of important value for theoretical research and breeding.