The impact of ethylene-mediated induced plant defenses in cotton on herbivore performance

Plants are able to compensate for herbivory by altering their growth and development patterns after being damaged. With this defense strategy, known as the tolerance defense strategy, plant fitness is unaffected by herbivore feeding. Tolerance is common in agro- ecosystems, and in previous studies, cotton (Gossypium hirsutum) has been found to tolerate early season herbivory by thrips spp. (Thysansura) and aphids (Hemiptera:Aphididae). In this study we set out to determine if the timing of attack affects cotton’s ability to tolerate herbivory by the cotton fleahopper, Pseudatomoscelis seriatus (Hemiptera: Miridae). We used cages to manipulate fleahopper presence on cotton during different weeks of flower bud production. We found no effects on plant growth and development parameters (rate of flower production and number of fruiting and vegetative branches) during the growing season, but by late season, fleahopper infested plants produced 13% more fruit than controls. Thus, cotton overcompensated for fleahopper herbivory, and is likely to have improved fitness. This study suggests that fleahoppers participate in mutually beneficial interaction with its host plant.