Diversity, Abundance and Diurnal Activity of Insect Pollinators of Onion (Allium cepa) in Northern Transitional Zone of Karnataka

The study on insect pollinators of onion ( ) recorded 16 species from 11 families across four orders, with hymenopterans Allium cepa being the dominant group (94.2%), followed by Diptera (3.1%), Lepidoptera (1.4%), and Coleoptera (1.3%).Among honeybees, Apis florea was the most abundant pollinator (34.65%), followed by sp.(30.84%).Pollinator activity peaked at 1000-1100 h, increasing with Tetragonula flowering progression from 50% to 90%.Maximum activity (7.73 visitors/m/5 min) occurred at 90% flowering.Diversity indices indicated higher species richness at 90% flowering (Shannon-Wiener index: 1.81; Simpson diversity: 0.81) compared to 50% flowering (Shannon-Wiener index: 1.67; Simpson diversity: 0.77).The findings highlight the significance of hymenopterans as primary pollinators.This study emphasizes the critical role of diverse insect pollinators in onion crop productivity, with peak pollination activity occurring during mid-morning hours.