Seasonal dynamics of spiders and insect pests in citrus orchards of district Sargodha, Pakistan.

Abstract

Citrus leaf miner, citrus whitefly and citrus psylla are the major insect pests of citrus orchards in district Sargodha, Pakistan. Spiders, being natural predators are helpful to keep the insect pest populations below economic enjoy level. The diversity and guild structure of spiders in the citrus orchards was recorded in the study. Seasonal dynamics of spiders and insect pests and predator-pest (spider-pest) relationships were also studied. In total, 2665 spiders belonging to 12 families, 23 genera and 43 species were captured. Species and family composition of spiders varied on the foliage and ground. Abundance of spiders among sites differed significantly. However, non- significant difference was observed in the richness, diversity and evenness among sites. Abundance and infestation of pest was found to synchronize with the abundance of spiders. Maximum infestation of citrus leaf miner, citrus whitefly and citrus psylla was recorded in March, 2014 supporting maximum spider abundance in this month. There was strong positive correlation between abundance of insect pests and predators (spiders) which suggested that spiders could effectively control insect pest populations in the field. Key worlds: spiders, leaf miners, whitefly, bio-control.