Fruit fly management measures

(Baonghean)Fruit flies are a major threat to the production of several types of vegetables and most types of fruit trees.

In Vietnam, four types of fruit flies have been identified as damaging fruit trees. To control fruit flies, farmers mainly use chemical pesticides for prevention, without determining the exact time of their appearance. This leaves a significant amount of pesticide residue in the fields and on the produce, causing food poisoning. The following are some measures for managing fruit flies.

Cleaning fields and gardens

Collect and dispose of all fallen fruit by burying it deep in the ground to reduce the number of fruit flies.

Fruit wrapping

During the fruiting stage, use good quality paper, cloth, or plastic bags with openings at the bottom, loosely tied at the top to wrap the fruit, ensuring it can still breathe properly.

Harvest the fruit early.

Choose the right time to harvest the fruit; do not leave the fruit to ripen too much on the tree, to minimize damage from flies.

Use traps and bait to kill flies:



Trap-making techniques.



Flies come to eat the protein bait.

- Methyl eugenol (ME) and Culure (CUE) are used as biological attractants to lure male flies for DTDB (pheromone trapping) purposes.

Instructions for use: Apply 2ml of attractant compound (ME or CUE + 20% insecticide) to cut fruit or thick cloth... replace the bait every 6 weeks. Hang the traps in a shady place, 1.5-2m high. Use 20-30 traps/ha. When approximately 10 flies are seen in each trap, spray with protein bait. Implement this on a large scale to control male flies.

- Currently, the market offers fruit fly attractants and insecticides such as Vizubon-D, containing 75% Eugenol and 25% Dibrom.

Instructions for use: Use 1-2ml of insecticide per trap. Hang 2-3 traps per 1000m². After 15-20 days, empty the dead flies, apply fresh insecticide, and hang the traps back on the trees. Combine with spraying protein bait when flies are seen entering the traps.

Protein bait spraying method

Sofri-Protein 10 DD: Produced by the Southern Fruit Research Institute. Composition: total protein 10% w/v.

Instructions for use: Mix 1 liter of Sofri Protein + 40 ml of Fipronil 5% + 10 liters of water and spray once per hectare. Spray in spots under the foliage, one spot per plant (1 m²/plant), do not spray on the fruit. (For vegetables, spray each spot 10 m apart).

Ento - Protein 150 DD: A product distributed by Hoa Binh Plant Protection Company.
Ingredients: total protein 150g/l.

Instructions for use: Mix 1 liter of ento-protein + 9 liters of water + 1 packet of Rigell 800WG (packet included). Spray 20 liters of the mixture per hectare. For fruit trees, spray spot by spot, in a mist form, 50 ml per spot (approximately 1 m²). For fruiting vegetables: Spray along the rows, one row apart, with spray points spaced 3-5 meters apart.

- Protein bait spraying phase

+ For fruit trees: Spray 1-1.5 months before harvest until harvest is complete.

+ For fruiting vegetables: Start spraying after fruit set until harvest is complete.

Note:

- Spray protein bait once a week, between 8-10 am, spraying the foliage and avoiding the fruit. Do not spray when it is about to rain. Clean the orchard, collect fallen and ripe fruit before spraying. Spraying over a wide area is recommended to increase the effectiveness of fly control.

- Mixing insecticide with protein bait attracts flies and kills both male and female flies. Dissolve the insecticide in water first, then add the protein bait, stir the mixture well, and spray immediately after mixing.

Nguyen Huy Khanh (Regional Plant Protection Center, Zone 4)