Farmers’ knowledge, perceptions and management of the moringa tree defoliator, Noorda blitealis Walker (Lepidoptera: Crambidae), in Niger

Moringa oleifera Lam. is a commercial crop in Niger consumed as a leafy vegetable on daily basis in urban areas. Its production is, however, hampered by a defoliator pest, Noorda blitealis Walker for which farmers lack a practical management approach. For this, a structured questionnaire was used to interview individual Moringa farmers (n = 120) in two producing areas (Maradi and Tillaberi) to assess farmers’ knowledge of N. blitealis, their perceptions, and management practices in Niger. Among the biotic constraints they faced, 70% of farmers ranked N. blitealis Walker as the most critical pest of Moringa. In the two regions, all the interviewed farmers could describe N. blitealis damage symptoms; however, only 21–25% of farmers were able to describe some of the development stages of N. blitealis. According to farmers, the perceived yield losses ranged from 4 to 99% across the regions, with the highest losses being recorded in the September–November production period. Farmers’ knowledge of N. blitealis and their management practices were not significantly associated with their socioeconomic profiles. Farmers in both regions relied primarily on synthetic insecticides (60–80%) to control N. blitealis damage, although most farmers misused them (unsuitable molecules, excessive applications, or no attention to preharvest interval). Interestingly, some farmers relied only on sole neem sprays (3–5%) or alternate sprays of synthetic insecticides with neem sprays (15% of farmers in Maradi). Some farmers (10–17%) prune the trees to prevent N. blitealis infestation, while other farmers (3–7%) release chickens into their fields to feed on the N. blitealis caterpillars. These results indicate a crucial need to train farmers in terms of basic knowledge regarding the pest’s biology and develop an integrated pest control approach that will minimize synthetic insecticides.