Fungivory: a new and complex ecological function of Doru luteipes (Scudder) (Dermaptera: Forficulidae)

Fungivoria: uma nova e complexa função ecológica de Doru luteipes (Scudder) (Dermaptera: Forficulidae)

Abstract

We report the discovery that the earwig predator Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) feed on Puccinia polysora Underw uredospore, the causal agent of Southern Rust of Corn (SRC), which is a primary disease affecting the maize crop in Brazil. We performed experiments in laboratory and greenhouse to test the effect of D. luteipes (1st/2nd and 3rd/4th instars, and adults) fungivory on the P. polysora uredospore concentration. All trials showed a significant reduction of the initial concentration of uredospore. There was a reduction in uredospore concentration with increase in number of D. luteipes feeding on them. We also tested the uredospore consumption by quantifying its percentage in the feces of D. luteipes. Nymphs of the 2^nd, 4^th instar and adults fed 88%, 85%, and 83.8% of the uredospore, respectively. For nymphs of the 3^rd instar, the percentage of uredospore consumption (75.6%) was statistically significant compared with the other groups. In greenhouse experiment, at twenty-eight days after plant inoculation with 9.9 x 10⁴ uredospores, the percentage of uredospore consumption was 81.7%. Our results confirmed the fungivory of D. luteipes on P. polysora uredospore. This is the first report of D. luteipes fungivory, which may play an important role in the biological control of P. polysora in corn.

Keywords:  earwig; southern rust; maize; biological control