Impact of insect pollination on the quantitative and qualitative characteristics of sweet orange, Citrus sinensis (L.) Osbeck

Abstract

Insect pollination plays a pivotal role in maintaining sustainable and profitable agriculture practices with limited environmental disturbance. This research was conducted to assess the diversity of floral visitor insects and their foraging and behavioral activities over two seasons. In addition, we determined the impact of insect pollination on the qualitative and quantitative parameters of sweet orange (cvs. Early Gold, Rhode Red, and Trovita). During seasons 1 and 2, seven insect species, including six Hymenopterans and one Dipteran, visited the sweet orange flowers and collected nectar and/or pollen. During the two seasons, the highest mean number of flowers visited (per min) by various floral visitor insects was recorded for Xylocopa tenuiscapa Westwood and the lowest for Nomia sp. The time spent (s/flower) was the highest in Nomia sp. and lowest in X. tenuiscapa. The fruit set, fruit yield, fruit weight, number of seeds/fruit, and total soluble solids (TSS) content were considerably higher with open pollination during the two seasons than with pollinator exclusion. In both seasons the highest fruit set, number of seeds/fruit, fruit weight, and fruit yield were noted in cv. Early Gold. To summarize, the quality and quantity of fruit production of sweet oranges were influenced by insect pollination.