Polinização da abóbora (Cucurbita moschata D.): biologia floral, visitantes florais e requerimentos de polinização

Abstract

The objective of this work was to study floral biology, floral visitors and their frequency of visitation, foraging behavior and pollination requirements, among other aspects for the cultivation of pumpkin (Cucurbita moschata D). The experiment was conducted in the city of Garanhuns during the periods of March and June of 2019. An area of 50 m2 was used. The species used was C. moschata D. early Brazilian girl cultivar. Near the plantation were some plants of guava, jamelão, cajá, passion fruit and other herbaceous species in time of flowering. To determine the pollination requirements, the efficiency of free, restricted and cross-pollinated pollination was studied. During 6 days, for 10 min every hour was counted bees that were visiting the flowers. The pollination requirement data were analyzed through analysis of variance through the RStudio program, adopting a significance level of 5%. The foraging frequency data were analyzed using Excel 2013. The flowers of C. moschata D. open at dawn, all being open at 5 o'clock. The stigma was receptive throughout the time the stigma receptivity test was done. The number of male flowers was greater than that of female flowers. The Trigona spinipes was the main visitor in the flowers of the pumpkins, having the peak of visit between 8h and 9h. T. spinipes showed monopoly behavior. Pollen and nectar collection behavior was observed. The female flowers that received the restricted pollination treatment did not produce fruit. The fruiting in the treatment with crossed manual pollination was greater in relation to the open (P <0.05). The ants influenced the least amount of venation in the free pollination, because in large quantities in the female flowers, they prevented the visit of pollinators. The work showed that C. moschata is dependent on pollinators for fruit production; that T. spinipes is the main visitor and possible pollinator of the region and that the ants act as repellents of pollinators, having a negative role in the crop.