The West African watermelon (Egusi melon), Citrullus mucosospermus
Fursa, Cucurbitaceae, is one of the vegetable crops subject to high pest and disease pressure, particularly root-knot nematodes. To reduce losses due to these nematodes, a field experiment was conducted at a research station to assess the efficacy of antagonistic fungi and botanical extract on root-knot nematodes parasitising Egusi crop. Two nematode control products, the biocontrol agent Trichoderma asperellum
T-12 and neem seed powder, were assessed separately and in combination for their efficacy against root-knot nematodes on the accession Egusi BEN 1-5-13, which is moderately tolerant to root-knot nematodes. The efficacy of the products was compared with that of the chemical nematicide Furadan (nematicide control) and untreated control. Application of Trichoderma asperellum
T-12 was at 108
and neem seed powder at 75 g plant-1
, one week before planting. Results indicated a reduction of final root-knot nematode population densities in roots by 89.51% and galling index by 68.86%, compared to those obtained with the control treatment. Application of these products in combination increased the average yields of unhulled and hulled seeds by 100% and 30%, respectively, compared to those of the nematicide control treatment. These results confirm the effectiveness of integrated management strategies to control root-knot nematodes.