Intraspecific variation in pollinators and herbivores and their effect on ecosystem services

Land use change is known to affect the diversity of pollinators and herbivores with consequences for crop production. Recent evidence shows that land use change also affects insect traits, with intraspecific variation in body size of pollinators and herbivores changing across a landscape gradient. However, the consequences of these changes in traits of different plant interactors on crop production have not been well-studied. Here we expose strawberry plants to different sized individuals of a key herbivore, the tarnished plant bug Lygus lineolaris, and an important pollinator, Bombus impatiens. We hypothesized that changes in body size of key species can be enough to affect crop productivity, and therefore looked at how the variation in body size of both key pollinators and herbivores can affect fruit size and damage in strawberry. We found that L. lineolaris decrease in size in more complex landscapes, and many studies on bee pollinators have shown that pollinators increase in size in more complex landscapes. We tested under controlled conditions how the individual and combined changes in size of B. impatiens and L. lineolaris affect strawberry fruits. We find that herbivore size, more than pollinator size, affected fruit production - with plants exposed to larger bugs producing smaller fruits. We conclude that land use changes at the landscape level are affecting insect traits with consequences for crop production.