Elevated air temperature shifts the interactions between plants and endophytic fungal entomopathogens in an agroecosystem
The possible effects of climate change on species interactions remain a very complex and challenging subject in community ecology. Here, we comparatively examine the interactions between maize (Zea mays) and an endophytic fungal entomopathogen (Beauveria bassiana) in a typical agroecosystem under both ambient and elevated air temperatures. We found that under ambient temperature certain key biological characteristics in maize (i.e., height, relative growth rate, biomass, and defense enzymes) and B. bassiana (i.e., conidia yield, germination rate of conidia, and virulence) were positively related to each other. Under elevated air temperature, however, we only detected positive effects of maize on B. bassiana (i.e., conidia yield, germination rate of conidia, and virulence), but little effect of B. bassiana on maize. These observations suggest that elevated air temperature could shift the interactions between plants and the endophytic fungal entomopathogens, possibly even from mutualism to commensalism. Both the nature and strength of species interactions are important for better understanding and predicting structure and stability of ecological communities in agroecosystems under climate change.