Effect of augmentative releases of the parasitoid, <i>Habrobracon hebetor</i> Say (Hymenoptera: Braconidae) using plastic cups on <i>Heliocheilus albipunctella</i> De Joannis (Lepidoptera: Noctuidae) in the Sahelian region of Burkina Faso

Abstract

The most important insect pest of the millet crop in Burkina Faso is the Millet Head Miner (MHM), Heliocheilus albipunctella De Joannis (Lepidoptera: Noctuidae). To reduce its damage, the use of the parasitoid, Habrobracon hebetor Say (Hymenoptera: Braconidae) constitutes the most promising control strategy. The present study aims to know the effect of augmentative releases of H. hebetor on this pest using a new parasitoid release technique. This new technique release consists of a recycled plastic cups containing Corcyra cephalonica Stainton larvae parasitized individually at different times (8, 12 and 24 hours) by H. hebetor females. These cups were installed in the millet fields of different villages (release villages) to control this pest H. albipunctella by H. hebetor, and maitained the control villages that didn’t receive any release. Our findings showed that plastic cups containing parasitized larvae at different times can be used to produce parasitoids. Thus, C. cephalonica larvae parasitized in 24 hours produced 280 H. hebetor, unlike larvae parasitized in 8 and 12 hours. Emerged H. hebetor had a male-biased sex ratio when the time of parasitism of C. cephalonica larvae by H. hebetor females was 24h. Releasing parasitoids into millet fields reduced the length of mines by 3.80 cm and two times higher parasitism of the pest by H. hebetor in the villages where parasitoids were released as compared to control villages. Finally, a millet yield gain of 31% was obtained in the parasitoid released fields. This new release technique of H. hebetor could be used in biological control programmes against MHM in the Sahel.