Senegal: Low cost white fly traps save mango crops (United Nations’ Integrated Regional Information Networks)

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Mango farmers in the Casamance region of Senegal are learning a low-cost method of trapping and killing a pest that has been devastating their crops.

Mango production became particularly important in the Casamance region following a civil conflict that left much of its farmland littered with mines. With the landmines yet to be removed, but mango orchards offer farmers an alternative. Mangoes require much less land than crops traditionally grown in the area, such as groundnuts, watermelons, and millet.

For the past four years, however, mango production in Casamance has been threatened by the white fly, which lays eggs in ripening fruit. The eggs hatch into maggots that cause the fruit to rot and fall to the ground. It’s a problem the farmers are now combating, with the help of government agricultural workers and aid organizations.

This past growing season, a simple but effective technology was tested. Attract-and-kill traps were made from recycled water bottles and a mix of methyl eugenol – a naturally occurring substance that attracts flies – and a pesticide that kills them. During the test, traps attracted and killed an estimated 60,000 flies each over 10 days.

The locally-made traps cost about 6 US dollars, or 4 Euros each. Imported traps, by comparison, sell for up to 27 US dollars, or 18 Euros, each.

The traps are a relief to farmers who were losing up to 90 per cent of their mango crops to the white fly.

Mango orchards are the primary source of income for many families, who are being hit by food shortages  due to poor rains. They are also one of the few crops that grow well during the rainy season.

Ibou Goudiaby has five hectares of mango trees in the Casamance region. He says the new trap will allow farmers to recover their plantations, which are their only source of revenue until landmine removal is complete.

Government agriculture workers and aid organizations trained a group of farmers to use the new, low-cost white fly traps. Now these farmers are training other mango producers. They will need to start using the traps soon, as mango trees will start to flower in January.

Experts note that keeping plantations clean and free from debris is the first line of defense against the white fly. They also recommend that any fruit that falls from the tree be buried at least 50 centimetres under the ground, to prevent any larvae in the fruit from reaching the surface.