Predation capability of Hippodamia convergens (Coleoptera: Coccinellidae) and Chrysoperla cornea (Neuroptera: Chrysopidae) feeding of Melanaphis sacchari (Hemiptera: Aphididae)

The sugarcane aphid, Melanaphis sacchari (Zehntner) Hemiptera: Aphididae), was first detected in Mexico in 2013. Since then, it has caused significant yield losses in sorghum, Sorghum bicolor (L.) Moench (Poaceae). The objective of this work was to evaluate, under laboratory conditions, the predation capability for the sugarcane aphid, measured as the consumption rate, of 2 predator species commonly used as biocontrol agents for different aphid species. We evaluated the consumption rate of larvae and adults of the convergent ladybeetle, Hippodamia convergens (Guerin-Men-eville) (Coleoptera: Coccinellidae) when exposed to 100 aphid specimens for either 30 or 60 min. A second experiment compared the consumption rate of males and females of H. convergens exposed to different densities (4, 8, 16, 32, 64, and 128) of aphids in a 24-h period. We also tested the consumption rate of larvae of the common green lacewing, Chrysoperla cornea (Stephens) (Neuroptera: Chrysopidae), in a 24-h period at different aphid densities (8, 16, 32, and 64). Larvae of H. convergens had a statistically significant higher consumption rate for the 30-min session compared to adults. However, for the 60-min session, the consumption rate was similar for both. The consumption rate between males and females at different aphid densities did not show statistical differences, except for the 64-aphid density; females consumed 85.9% of the aphids, compared to 68.2% by the males. Finally, a positive correlation was observed between prey density and prey consumption of C. cameo larvae. The regression model showed that they could consume an average of 15 aphids per d.