The African Rice Gall Midge, Orseolia oryzivora H. & G., is an important insect pest recorded in 20 countries in Sub-Sahara Africa. In Burkina Faso, the insect pest particularly prevails in Western and South-Weste...The African Rice Gall Midge, Orseolia oryzivora H. & G., is an important insect pest recorded in 20 countries in Sub-Sahara Africa. In Burkina Faso, the insect pest particularly prevails in Western and South-Western of the country where both biotic and abiotic conditions favor its development. The insect pest can damage up to 60% of rice tillers in Western Burkina Faso. A study was conducted during the 2011 wet season in the Kou Valley, located 25 km North-West of Bobo-Dioulas- so, Western Burkina Faso. Its objective was to evaluate the damage of this insect pest in farmers’ fields in relation with rice transplanting periods. The Kou Valley rice scheme, 1200 ha, was divided into two zones within which 48 farmers’ fields were randomly selected in relation with rice transplanting periods: P1: 1st period;P2: 2nd period and P3: 3rd period;that is 16 fields per period. Both agronomic and entomological evaluations were performed each week starting from the 21th day after transplanting (DAT) up to 84 DAT. Results showed that the highest average damage level (16% of galls) was recorded in the 3rd transplanting period. The highest larval and pupal parasitism was recorded in P3 at 84 DAT. Pupal parasitism due to Aprostocetus procerae Risbec was higher than larval parasitism due to Platygaster diplosisae Risbec. Lastly, the lowest yield (4.78 t/ha) was recorded in P3. These results can be used in the implementation of an integrated pest management strategy for this insect pest in the Kou Valley.展开更多
文摘The African Rice Gall Midge, Orseolia oryzivora H. & G., is an important insect pest recorded in 20 countries in Sub-Sahara Africa. In Burkina Faso, the insect pest particularly prevails in Western and South-Western of the country where both biotic and abiotic conditions favor its development. The insect pest can damage up to 60% of rice tillers in Western Burkina Faso. A study was conducted during the 2011 wet season in the Kou Valley, located 25 km North-West of Bobo-Dioulas- so, Western Burkina Faso. Its objective was to evaluate the damage of this insect pest in farmers’ fields in relation with rice transplanting periods. The Kou Valley rice scheme, 1200 ha, was divided into two zones within which 48 farmers’ fields were randomly selected in relation with rice transplanting periods: P1: 1st period;P2: 2nd period and P3: 3rd period;that is 16 fields per period. Both agronomic and entomological evaluations were performed each week starting from the 21th day after transplanting (DAT) up to 84 DAT. Results showed that the highest average damage level (16% of galls) was recorded in the 3rd transplanting period. The highest larval and pupal parasitism was recorded in P3 at 84 DAT. Pupal parasitism due to Aprostocetus procerae Risbec was higher than larval parasitism due to Platygaster diplosisae Risbec. Lastly, the lowest yield (4.78 t/ha) was recorded in P3. These results can be used in the implementation of an integrated pest management strategy for this insect pest in the Kou Valley.
