How to fight fruit flies-infection on hass avocado

KAMPALA - “Fruit flies are small, stationary, brown, greenish insects occasionally found sucking sap from avocado leaves, and are protected by the shelf,” explained Robert Mugamba, the chief executive officer of NileCado Ltd, during the Harvest Money Expo that began on February 14 and ended on February 16 at Namboole Stadium.

To fight fruit flies, you have to be aware of their symptoms. Mugamba mentions discolouration, malformation, leaf and fruit drop, and retarded growth.

Mugamba reminded avocado farmers to sanitise the orchard and do periodic scouting. (All Photos by Mpalanyi Ssentongo)

“When the fruit reaches about the size of a golf ball, a sling lesion appears as a slight puncture mark surrounded by a white exudate,” Mugamba said.  He added, “As the fruit develops, the lesion becomes dry and turns into a distinct star-shaped crack on the skin surface.”

To keep them at bay, Mugamba recommends traps. These can be commercial pheromone traps made of Methyl Euginol at 20 traps per acre in every eight to 10 trees. When you notice the infections, Mugamba says you can remove the affected fruits. For example, those with dimples and oozing sap, twice a week.

Expo-goers during training.

Mugamba reminded avocado farmers to sanitise the orchard and do periodic scouting. This ensures that there are no weeds that are affecting the growth of the avocado plants, which can later breed fruit flies.

Harvesting

Avocado growers must adopt proper harvesting methods so as not to lose their harvest in the end.

Mugamba observed that when the avocado is harvested early it often turns out tasteless, watery and wrinkled.

Immature avocado sinks below the water surface while the mature on float. Another method of determining whether the crop is ready for harvesting is to pick a few fruits when they are apparently mature and then leave them to ripen in a warm place,” says Mugamba.

“If those soften without shriveling within a week at about 27 degrees then the crop is ready for picking.”

For proper harvest, Mugamba advises clipping the fruit from the tree with secateurs in such a way that a short stem portion of about 0.5 cm is left on it. He also recommends that cotton gloves be used during picking and grading.

This will ensure hygiene during handling. To avoid contamination after the harvest, Mugamba says the fruit should not be put on the ground, but rather be protected.

The Harvest Money Expo was made possible by ENGSOL, ABI, Bella Wine, Uganda Development Cooperation, Tunga Nutrition, and Pepsi in partnership with the Kingdom of Netherlands.