Brinjal Shoot and Fruit Borer Control

Symptoms

In the early stage caterpillars bore into tender shoots, causing the growing tips to droop, wilt and dry, a symptom called dead heart. Later they bore into the fruits, leaving a small entry hole often plugged with excreta, while inside the larva tunnels and feeds, making the fruit rot from within. Damaged fruits show holes and brown frass and are unfit for sale or eating. A single fruit may carry one pinkish larva.

Damage

The brinjal shoot and fruit borer Leucinodes orbonalis is the most destructive pest of brinjal and can cause fruit losses of up to 80 percent. Because the larva lives hidden inside the shoot or fruit, sprays reach it poorly, making it one of the hardest pests to control. Shoot boring reduces plant growth and fruit boring directly destroys the marketable produce. The bored fruits also rot and are rejected in the market, so the economic loss is very high.

Organic & cultural control

Regularly clip and destroy the drooping bored shoots along with the larva inside, ideally once or twice a week, as this is one of the most effective steps. Install pheromone traps at 4 to 5 per acre to monitor and mass trap male moths. Apply neem cake in the soil and spray neem seed kernel extract at 5 percent. Release the egg parasitoid Trichogramma chilonis. Collect and destroy all bored fruits, and never leave damaged fruits or shoots in the field as they keep the pest going.

Chemical control

When trap catches and damage rise, spray insecticides such as chlorantraniliprole 18.5 SC, flubendiamide, emamectin benzoate 5 SG or novaluron, alternating between groups at fortnightly intervals to manage resistance, since the pest resists older chemicals. Spray to cover shoots, flowers and young fruits. Avoid spraying close to harvest because brinjal is picked frequently. Always follow the product label dose, strictly observe the pre harvest interval and consult your KVK or agronomist before spraying.

Always follow the product label, the recommended pre-harvest interval, and your local KVK or agronomist. Pesticide approvals change, so verify before use.

Prevention

Grow tolerant or resistant varieties where available. Deep summer ploughing destroys pupae in the soil and follow crop rotation away from brinjal. Start pheromone traps right from transplanting to catch the first moths and reduce egg laying. Practice weekly clipping of dead heart shoots and prompt removal of bored fruits throughout the season. Avoid carrying the pest in seedlings, keep fields clean of crop debris and do not grow brinjal continuously in the same plot.