Pollination Efficiency of the Indian Bee, Apis cerana indica Fab. in Bitter Gourd in Tamil Nadu, India

Cucurbits are cross-pollinated vegetables that rely on insect pollination for their reproduction and yield. Bitter gourd is a major cucurbitaceous plant widely cultivated in India. Though affected by several pests and diseases, the yield of bitter melon varies widely due to a pollination gap. Stingless bee – Tetragonula iridipennis, little bee – Apis florea, Indian bee – Apis cerana indica, and blue banded bees – Amegilla zonata are the most important pollinators of bitter gourd in the Tamil Nadu region of India. The present study was conducted to evaluate the effectiveness of the Asiatic honey bee, Apis cerana indica, in enhancing the yield of bitter gourd. Apis cerana indica is widely used by South Indian farmers, as it adapts to the tropical climate of the region. The honey bee colonies were introduced at 10% flowering and were maintained in the field until the last harvest. Colonies were kept amid the cropped field, covered with an insect net to prevent the escape of bees to nearby fields. Colonies were also kept without caging, as well as at a distance of 100 and 200 meters from the field. Control was maintained by not introducing any new colonies. The crop was cultivated using organic farming methods, with no use of synthetic chemical insecticides that could harm the honeybees and their activities. The increase in crop yield was up to 27.60% in the study area. The honey yield was also considered to study the increase in farmers’ income. Bee hives placed inside the cropped area and at a distance of 100 m have shown better fruit and honey yields, and are therefore advisable for farmers.