D3426: Advancing biological control of coffee leaf miner through plant diversification

The landscape simplification added to over reliance on pesticides reduces natural biological pest control. To offset land-use change, strategic habitat enhancement through diversification of non-crop areas has the potential to attract and provide resources to natural enemies for enhanced conservation biological control. Here, we propose and test a diversified coffee system containing plantings of perennial plants (Inga edulis, Senna macranthera and Varronia currasavica) and the maintenance of the non-crop plants into the coffee crop (Coffea arabica). To evaluate the pest control services associated with our diversified system, we compared the damage of coffee leaf miner Leucoptera coffeella (Lepidoptera: Lyonetiidae) in two coffee systems: diversified and no pesticides versus a conventional coffee monoculture during 2019, 2020 and 2021. The diversified system with no pesticides exhibited similar infestation by coffee leaf miner and loss levels to conventional coffee system in 2019. In 2020, the infestation was higher in diversified coffee system. However, in 2021, the infestation by coffee leaf miner was similar in both the conventional the diversified coffee systems. Our results suggest, as with many studies, that infestation levels vary between years, and that strategic diversification maintains natural control of the coffee leaf miner.