Fruit flies must be controlled on sweet pumpkin, bottle gourd, ridge gourd, snake gourd, pointed gourd, aubergine and fruit, because they are very harmful to gourd crops. Pheromone traps can be used against fruit flies on all gourd crops, so it is important to know how to set them.

The female fly inserts her ovipositor into the lower part of young fruit and lays eggs. A watery liquid oozes from the egg-laying spot and dries to a brown colour. The larvae that hatch start eating the flesh of the fruit, which becomes deformed, turns yellow, rots and drops.

• Collect and destroy or burn infested fruit and flowers.
• Cover young fruit with paper or polythene.
• Set pheromone traps for gourd crops as soon as the first flowers appear.
• Set them at a rate of three per 10 decimals.
• Plough the land well so that birds can eat the pupae.
• BioBT can be used as a biological pesticide.
• Biodarma powder can be used to keep plants and fruit glossy and healthy.

Pheromone traps work very well against the pest. One trap per 4 to 5 decimals is enough, but the water in the trap must be changed regularly and dead insects cleared out. One pheromone lure works for two months. Tie the trap to a bamboo pole 1 foot above the plant canopy.

• Chop 100 g of ripe sweet pumpkin or other gourd fruit finely, mix in a little poison (the text gives 0.25 g of a carbaryl product) to make a poison bait, and place it in earthen pots at intervals in the field.
• Spray a cypermethrin-group insecticide (the text names "Irdi") mixed at 1 ml per litre of water.
• Mix a little poison (0.25 g of the carbaryl product) into mango or date juice, keep it in a bottle with a window cut in it, and place the bottles at intervals in the field.

• Do not eat or sell the vegetables within 15 days of spraying.
• Read the label on the pesticide carefully before use.
• Take the necessary precautions when using and storing pesticides.
• Excessive use of pesticides harms health and the environment.
• Wearing protective clothing is essential.

Source: Jagonews24. First published in Bengali on The Agro News.