Reproduction of Aphidoletes aphidimyza (Diptera: Cecidomyiidae) on a banker plant system of sorghum with Melanaphis sacchari (Hemiptera: Aphididae) and its oviposition selection between this system and eggplant with Aphis gossypii (Hemiptera: Aphididae)

Abstract

To control Aphis gossypii Glover infestation of eggplant during the hot season in greenhouses, a banker plant system for Aphidoletes aphidimyza (Rondani) was developed using Melanaphis sacchari (Zehntner) as an alternative prey on sorghum as banker plants. In this study, reproduction of Aphidoletes aphidimyza on this banker plant system was studied by estimating the intrinsic rate of increase (rm) based on results of laboratory and greenhouse experiments and the effects of the density ratio of Aphis gossypii to M. sacchari on its oviposition selection between this system and the system of eggplant with Aphis gossypii. Our results showed that rm of Aphidoletes aphidimyza reared on M. sacchari was 0.193 at 25 °C, which was higher than that of Aphidoletes aphidimyza reared on Aphis gossypii (0.147) (Higashida et al. 2016 Appl Entomol Zool 51: 445–456). Aphidoletes aphidimyza always laid more eggs on sorghum with M. sacchari than on eggplant with Aphis gossypii except at the highest density ratio of Aphis gossypii to M. sacchari. In greenhouse experiments where equal numbers of both aphid species were provided, Aphidoletes aphidimyza laid more eggs on eggplant with Aphis gossypii than on sorghum with M. sacchari.