OVERCOMING SELF-INCOMPATIBILITY IN PASSION FRUIT BY DOUBLE POLLINATION IN ANTHESIS STAGES

Abstract

The Passiflora species are grown worldwide for theirs edible fruits, chemical properties, and also by their ornamental values. In Brazil, is starting its use as ornamental proposes, although the country is the principal center of diversity for the genus. Passion fruit (Passiflora edulis Sims.) is the most cultivated species, among the passifloras, and presents sporophytic self-incompatibility. Self-fertilization is necessary to obtain homozygous plants for breeding programs. In this work, we evaluated the efficiency of three methods to overcoming self-incompatibility barriers: bud selfing, double self-pollination at anthesis and self-pollination post-anthesis stages. The control treatment was self-pollination at anthesis stage. Fruit set was evaluated at the 7th day after pollination. Self-pollinations, made in anthesis stage, did not set fruit, indicating that all plants were self-incompatible. In bud selfing was obtained 16.67% fruit set, suggesting that self-incompatibility barriers were not yet completely established. On the other hand, in the double self-pollinations with four hours interval at anthesis stage resulted 10% fruit set and did not differ statistically at level 5% of probability. Self-pollination at anthesis (control) and post-anthesis did not result in fruit set. In self-pollination 24 h post-anthesis stage the fruit set could be prevented due self-incompatibility or failure of stigma receptivity. This results represent a new and easy way of obtain homozygous plants in passion fruit self-incompatibles.