Estudo comparativo da poliniza??o de Mangifera indica L. em cultivo convencional e organico na regi?o do Vale do Submédio do S?o Francisco

摘要

This study was carried out in 2005 and 2006, in a commercial mango Tommy Atkins plantation on Frutex Farm, in Petrolina-PE. The objective was to verify the floral biology as well as the comparative study of behaviour, the frequency and the seasonality of the floral visitors in both organic and conventional crops. The mango tree inflorescences present male and hermaphrodite flowers (2:1), with predominance of the first ones in the basis of the panicles. The anthesis is diurnal, asynchronic, with liberation of strong and sweat odour. The flowers present dicogamy, characterized by the anthers dehiscence 24 hours after the anthesis. The nectar production is continuous and in small amounts, on an average of 0,045μL/flower. Concerning the flower visitors, 21 species were registered, belonging to the orders Diptera, Hymenoptera, Lepidoptera and Odonata. Apis mellifera was the most frequent visitant in both types of crops. Among the Diptera, Belvosia bicincta (17,7%) and Musca domestica (10,2%) were the most frequent visitors in conventional and organic crops, respectively. The diversity and number of visitors were higher in the organic crop. The use of agrotoxics during the flowering period reduced the visit of bees (50%) and Diptera (20%). Because of its behaviour, frequency and active movement in the inflorescences, Apis mellifera was considered as the most efficient pollinator of the crop for the region of the S?o Francisco Submédio Valley.