Foraging behavior and visit optimization of bumblebees for the pollination of greenhouse tomatoes

Abstract

The tomatoes grown under greenhouse conditions require supplemental bee pollination for the better fruit set. The present study was conducted to evaluate the optimized role of bumblebees (Bombus terrestris L.) for tomato pollination under greenhouse conditions. The impact of increasing number of floral visits (i.e. 1 to 5) on physical and biochemical properties of tomato was studied on tomato variety ‘Grande’ grown on an area of 500 m2. The self-pollination and hand vibration treatments were maintained for the comparison. The foraging behavior in terms of colony traffic, stay time and visitation rate was also studied. The maximum average outgoing bumblebees (7.38 individuals) were recorded at 10:00 while the maximum average incoming (6.75) were recorded at 2:00 pm. The three visits of bumblebees on a single flower resulted in the maximum improvement in physical (higher fruit length, fruit weight, fruit weight, number of seeds per fruit, weight of 100 seeds) and biochemical properties (vitamin C, shelf life) as compared to hand vibration and self-pollination treatments. There was no improvement in physical and biochemical properties in fourth or fifth visit. Bumble bee pollinated fruits had low TSS, pH and postharvest weight loss than that of self-pollinated and hand vibrated treatments. Therefore, three visits of bumblebees per flower are enough to get the optimum production of tomato under greenhouse conditions.

Keywords

• Colony traffic
• Stay time
• Visitation rate
• Physical and biochemical properties
• Hand vibration
• Self-pollination