Plant diversification is a strategy for pest management in agroecosystems. However, a major hurdle in the adoption of this management practice by farmers is related to doubts concerning its effects on crop productivity. Here we assess coffee production and natural control of coffee pests in the presence or absence of leguminous trees bearing extrafloral nectaries (Inga edulis). We compared coffee yield, coffee damage caused by coffee leaf miners (Leucoptera coffeella) and coffee berry borers (Hypothenemus hampei) and parasitism and predation of coffee leaf miners in a replicated field experiment. To evaluate the effect of proximity of the nectar source on natural control, we also assessed pest control and production along transects of 50 m extending from the Inga trees. Production per coffee plant was equal in both systems but coffee fruits were heavier in coffee consorted with Inga trees. In the most productive year, coffee production was higher on plants closer to the Inga trees. Damage caused by coffee leaf miners and coffee berry borers was lower in coffee with Inga trees and increased with distance from the trees. Parasitism of coffee leaf miners and predation by wasps did not increase in coffee consorted with Inga, neither decreased with distance from the trees. Therefore, Inga trees enhanced coffee production and increased natural control of coffee pests.

植物多样化是农业生态系统有害生物管理的一种策略。然而，农民采用这种管理方法的一个主要障碍是对其对作物生产力的影响的怀疑。在这里，我们评估了在有或没有带有花外蜜腺的豆科树（Inga edulis）的情况下咖啡生产和咖啡害虫的自然控制。我们比较了咖啡产量，造成咖啡潜叶虫（咖啡损坏鸥coffeella）和咖啡浆果蛀虫（Hypothenemus hampei在重复的田间试验）和寄生和咖啡潜叶虫的捕食。为了评估靠近花蜜源对自然防治的影响，我们还评估了沿从 50 m 延伸的横断面的害虫防治和生产。英加树。两种系统中每株咖啡的产量相等，但与印加树搭配的咖啡中的咖啡果实更重。在产量最高的年份，靠近印加树的植物的咖啡产量更高。咖啡潜叶虫和咖啡浆果蛀虫造成的损害在印加树咖啡中较低，并且随着与树木的距离增加而增加。咖啡潜叶虫的寄生和黄蜂的捕食在与Inga搭配的咖啡中没有增加，也没有随着与树木的距离而减少。因此，印加树提高了咖啡产量并增加了对咖啡害虫的自然控制。