Jackfruit Bud Weevil

📖 Description

Jackfruit Bud Weevil (Diaphananthus circulatus) is a specialist pest of jackfruit across the Indian subcontinent, particularly severe in the major jackfruit-growing belts of Kerala, Karnataka, Tamil Nadu, Maharashtra, Andhra Pradesh, Assam, West Bengal and Tripura where India is the world’s largest producer of jackfruit (over 100,000 hectares cultivated, with the crop gaining prominence as a high-value food security and climate-resilient tree). The pest is particularly damaging because (a) it specifically targets the male flower spikes and developing female buds — the most vulnerable plant parts, (b) infested male flower spikes dry up and fall prematurely, reducing pollination success and fruit set, (c) infested female buds fail to develop or produce deformed and undersized fruits, (d) the entry wounds created by adults and grubs allow secondary fungal pathogens (Rhizopus, Botryodiplodia) to cause fruit rot — often more damaging than the direct pest injury, and (e) the grubs develop inside the buds and flower spikes where contact insecticides cannot reach, making control difficult. The pest is most severe in homestead and backyard jackfruit trees (the dominant production system in India) where regular monitoring and management are challenging. IPM with weekly collection and destruction of fallen male flower spikes (the single most effective control measure), light trap monitoring, neem-based sprays on male flower spikes during evening adult activity, fruit bagging for high-value fruits, and need-based insecticide application during peak adult activity (Mar-Apr in South India) provides effective and sustainable control. The pest is a particular concern for organic jackfruit growers (a growing market segment in India for export of ripe bulbs and value-added products like chips and papad) because the pest can render fruits unsaleable even when present at low density.