Diversidade de insetos e eficiência de polinização em pomares de Passiflora edulis f. flavicarpa (Deg) (Malpighliales: Passifloraceae)

Abstract

Passiflora edulis f. flavicarpa (Deg.) (Malpighiales: Passifloraceae), a plant popularly known as yellow passion fruit, is a native fruit of Brazil with great importance in the agricultural sector. The crop has great productive potential, however, it is dependent on cross pollination for fruit picking. Pollination in the passion fruit crop represents a fundamental production factor in the management, just as it is important to the presence of floral visitors and effective pollinating agents (bumblebees). Pollination by visiting floral insects is essential for high productivity with low production costs, which is potentially increased due to the practice of artificial pollination, which requires manpower. In order to compare the indexes of passion fruit blossoms submitted to natural pollination by bumblebees and to artificial pollination, experiments were carried out in two sample areas, one orchard with agroecological cultivation and another orchard with conventional cultivation. the diversity of insects, in general, of pollinating agents. In order to compare the adhesive indexes, the floral petiole of six flowers per plant was marked with colored adhesive strips on sunny days in order to obtain a total of 96 flowers marked on each evaluated day and in each type of pollination, in a total of 16 plants, in each sample area, in a sample period of 95 days. In order to evaluate species richness, abundance and frequency of possible pollinator insects, flowers and vegetative parts of the orchards were sampled by transect walking between the crop rows, starting at distinct points at the edges and moving inland until reaching the center point of the orchards. This sampling was performed in the period from 3:00 p.m. to 4:00 p.m., every five days, for four months. During the sample period, 4,304 specimens of insects were distributed, distributed in six orders and 21 species. The orders Hymenoptera, Coleoptera and Hemiptera had the greatest diversity of species. However, agroecological cultivation presented greater diversity of insects compared to conventional cultivation. The occurrence of pollinating agents (bumblebees) in the areas obtained different values. Xylocopa had high abundance in both areas, with a higher average in the agroecological area. In the orchard with agroecological cultivation there was greater glue of the flowers. Artificial pollination in both sites had a higher index of flower glue, being more effective in relation to total glue indices and per plant. The natural pollination despite having lower indexes, obtained a good percentage of glue, demonstrating the presence and efficiency of pollinating agents in the areas with agroecological and conventional crops. It is concluded that agroecological management, mainly due to the diversification of crops and the environment that is more conducive to the presence of pollinators, influences the richness of pollinators and insect diversity.