Temperature‐dependent development, parasitism and longevity of the braconid parasitoids, Fopius arisanus Sonan and Diachasmimorpha longicaudata Ashmed on Bactorcera invadens Drew Tsuruta & White, was evaluated across five constant temperatures (15, 20, 25, 30 and 35°C). Developmental rate decreased linearly with increasing temperature for both the parasitoid species. Linear and Brière‐2 nonlinear models were used to determine the lower temperature threshold at which the developmental rate (1/D) approached zero. For F. arisanus, lower thresholds to complete development estimated with the linear and nonlinear models were 10.1 and 6.9°C, respectively. The total degree‐days (DD) required to complete the development estimated by the linear model for F. arisanus was 360. In D. longicaudata, the linear and nonlinear models estimated lower thresholds of 10.4 and 7.3°C, respectively, and the total DD estimated was 282. In F. arisanus, percentage parasitism differed significantly across all temperatures tested and was highest at 25°C (71.1 ± 2.5) and lowest at 15°C (46.4 ± 1.4). Parasitoid progeny sex ratio was female biased at all temperatures except at 20°C. In D. longicaudata, percentage parasitism was highest at 20°C (52.2 ± 4.0) and lowest at 15°C (27.7 ± 2.5). Parasitoid progeny sex ratio was female biased and similar for all temperatures. Adult longevity of both parasitoids was shortest at 35°C and longest at 15°C, and females lived significantly longer than males at all temperatures tested. Our findings provide some guidance for future mass rearing and field releases of the two parasitoids for the management of B. invadens in Africa.

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Farming systems in cocoa over the last three decades have involved the use of new hybrid plant varieties, which produce pods throughout the year, intensified fertilizer use, and misguided pesticide applications by some farmers. Resource availability in terms of abundance of feeding and breeding sites and ecological disruption as a consequence of climate change and bad agronomic practices have increased the importance of insect pests on cocoa. Historically the major management tool for hemipteran pests has been calendar spraying with conventional insecticides. Considerable progress was made at the turn of the last century by replacing organochlorine insecticides for cocoa mirid control. But inappropriate timing and inefficient application is probably reducing the viability of otherwise acceptable products in some areas. Integrated Pest Management (IPM) strategy for mirids and other insect control should involve great investment in pest surveillance, and be based primarily on the use of cultural practices of removal of excess chupons, shade management and Opinion Article

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