Effect of Visual Cues and a Fermentation-Based Attractant Blend on Trap Catch of Two Invasive Drosophila Flies in Berry Crops in Mexico.

Drosophila suzukii (Matsumura) and Zaprionus indianus (Gupta) (Diptera: Drosophilidae) are invasive pests of economic importance worldwide. This study was undertaken as a first step to investigate the interaction between visual and chemical cues on the captures of D. suzukii and Z. indianus under field conditions. Specifically, we evaluated the effect of color cardboards and their combinations on the capture of these drosophilids by attractant-baited multihole traps in blackberry and blueberry crops. Color had a significant effect on the captures of D. suzukii and Z. indianus by attractant-baited traps in both crops. Overall, attractant-baited traps with yellow and yellow + green cards captured the highest number of flies compared to attractant-baited traps using cards of other colors or without cards. Multihole traps without attractant and color cardboards caught very few flies of both species. In general, more females than male D. suzukii were captured, but no sexual differences were found in the captures of Z. indianus. The results obtained will be useful for the development of a monitoring or mass trapping system for the management of D. suzukii and Z. indianuspopulations in Mexico.