Natal Host Plants Can Alter Herbivore Competition.

Huipeng Pan,Evan L Preisser,Youjun Zhang,Xiaoguo Jiao,Qingjun Wu,Wen Xie,Shaoli Wang,Qi Su,Martin Schädler

doi:10.1371/journal.pone.0169142

Abstract

Interspecific competition between herbivores is widely recognized as an important determinant of community structure. Although researchers have identified a number of factors capable of altering competitive interactions, few studies have addressed the influence of neighboring plant species. If adaptation to/ epigenetic effects of an herbivore’s natal host plant alter its performance on other host plants, then interspecific herbivore interactions may play out differently in heterogeneous and homogenous plant communities. We tested wether the natal host plant of a whitefly population affected interactions between the Middle-east Asia Minor 1 (MEAM1) and Mediterranean (MED) cryptic species of the whitefly Bemisia tabaci by rearing the offspring of a cabbage-derived MEAM1 population and a poinsettia-derived MED population together on three different host plants: cotton, poinsettia, and cabbage. We found that MED dominated on poinsettia and that MEAM1 dominated on cabbage, results consistent with previous research. MED also dominated when reared with MEAM1 on cotton, however, a result at odds with multiple otherwise-similar studies that reared both species on the same natal plant. Our work provides evidence that natal plants affect competitive interactions on another plant species, and highlights the potential importance of neighboring plant species on herbivore community composition in agricultral systems.

Highlights

We find that the result of interspecific competition between herbivores can be reversed when two cryptic species (MEAM1 and MED) of the whitefly Bemisia tabaci are reared on natal host plants different than the plant species on which they compete
When cabbage-derived Middleeast Asia Minor 1 (MEAM1) and poinsettia-derived MED were reared together on cotton, MED increased in abundance and excluded MEAM1 by the seventh sampling period in all of the experimental replicates
We found that the offspring of poinsettia-derived MED competitively excluded the offspring of cabbage-derived MEAM1 when reared together on poinsettia and on cotton

Summary

Introduction

We find that the result of interspecific competition between herbivores can be reversed when two cryptic species (MEAM1 and MED) of the whitefly Bemisia tabaci are reared on natal host plants different than the plant species on which they compete. When cabbage-derived MEAM1 and poinsettia-derived MED were reared together on cotton, MED increased in abundance and excluded MEAM1 by the seventh sampling period in all of the experimental replicates (fig 1B).

Results

Conclusion