Biological Control of African Rice Gall Midge (Orseolia oryzivora, Harris and Gagné) in Nigeria: A Review

African rice gall midge (AfRGM), Orseolia oryzivora Harris and Gagné (Diptera: Ceccidomyiidae) is a serious insect pest of lowland rice in Africa, and is capable of causing total crop failure in endemic areas. Of all the control measures adopted in the management of African rice gall midge in the recent years, biological control has been advocated. Unfortunately, so far, only few biological control agents e.g. Platygaster diplosisae Risbec and Aprostocetus procereae Risbec have been identified with high potentials for the control of the pest. Hence, there is paucity of information on the bio-control agents associated with AfRGM, and the efficiency of the identified ones in the management of African rice gall midge. In this review therefore, efforts were made to put together the hitherto fragmented information available on the distribution, host range, biology/life-cycle, ecology and the potentials of various bio-control agents associated with rice gall midge. The effects of abiotic and biotic factors on the efficiency of the bio-control agents were also discussed. The aim is to enhance farmers’ knowledge about these agents with intent to assist them in the use/adoption of bio-control agents or integrating them with other control methods for improved management of rice gall midge.