The effect of refuge block on the insect visitors to Apple crop in Batu, East Java

Abstract

Pollination is an ecological process that provides important services to human. Pollination service in agroecosytems depends on several factors, including the land management systems used by farmers. The research aims to determine the daily and seasonal variation of insect pollinators visiting the apple tree and refuge block in apple Batu, East Java. Observations on insect pollinators were done visually, were patterns of daily visit of insect pollinators to flowers analyzed by comparing the frequency of visiting in period range of time I, II, III, and IV. Enviromental factors (temperature, humidity and light) were measured. Comparative data analysis of insect community structure and refuge block obtained from the abundance and diversity (Shannon-Wiener). Daily and seasonal variation of insect pollinators of apples was done comparing the rates in flowering and fruiting seasons. Insect pollinators of apples collected in the spring plantation was higher (234 individuals) than the fruit season (169 individuals). Diversity index value of insect pollinators in the spring was higher (2.06) compared to the fruit season (1.87). Abundance of insect pollinators of flowers and fruits between seasons, is significantly different based on significance value of < 0.05. The similarity between spring and fruit season with Bray Curtis index is 0.93 %. Community structure of insect pollinators in apple plantations dominated from genus Apis mellifera (44) and Sphecidae (24), while in the fruit season was by the genus Formicidae (55) and Syrphidae (31). Analysis of environmental factors includes temperature, humidity and light intensity on the abundance of insect pollinators found a positive correlation with the R-square value of 66.4 %.