Herbivore Identity and Density Interact to Determine Plant-mediated Interactions between Herbivores
by Nannan Zhang, Chinese Academy of Sciences
April 6, 2022
Plants are often exposed to multiple herbivores and densities of these attackers often fluctuate greatly in the field. Herbivore identity and density are known to be two major drivers of plant-mediated interactions among herbivores, but their combined effects are poorly understood.
The Invasive Ecology Group from the Wuhan Botanical Garden of the Chinese Academy of Sciences addressed this research gap using Triadica sebifera (tallow), an aggressive woody invader, and two potential biological control agents, Bikasha collaris (flea beetle) and Heterapoderopsis bicallosicollis (weevil).
The researchers investigated how variations in the intensity of leaf damage caused by flea beetle or weevil adults affected the performance of root-feeding flea beetle larvae through manipulation of the density of these two adult herbivores.
They found that weevil leaf damage decreased larval flea beetle survival as leaf damage intensities increased. In contrast, herbivory by adult flea beetles facilitates larval survival at lower feeding intensity, and an effect that was reversed at higher feeding intensity. Furthermore, chemical analysis showed that root primary and secondary metabolism might underlie the observed effects on flea beetle larvae.
Read the Ecology paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3647