Induced defenses to herbivory are physical, nutritional, and allelochemical traits that change in plants following damage or stress, and that reduce the performance and/or preference of herbivores. The aim of this study was to verify the occurrence and effect of induced responses in B. brevipes against herbivores through the manipulation of its leaves and its consequences to herbivore foraging behavior. We selected 15 plants, and 3 shoots per plant were designed for one of the three treatments: damaged shoots (simulation of the main types of foliar herbivory and insect exclusion), damaged control shoots (insect exclusion), and control shoots (not manipulated). Water and nitrogen content, tannin concentration, levels of herbivory, and shoot growth rates were compared among treatments through ANOVA. Leaf quality differed among treatments. Damaged leaves presented higher tannin concentration (df=2.0; F=8.57; P<0.05), and lower water (df=2.0; F=7.64; P<0.05) and nitrogen content (df=2.0; F=18.60; P<0.0001), but experienced higher rates of herbivory (df=2.0; F=12.82; P<0.0001) than leaves on control shoots. Moreover, shoots that were experimentally induced showed higher increment in final shoot length, a parameter that estimates fitness. These results suggest that simulated herbivory on B. brevipes reduced the nutritional quality of its leaves and increased the amount of secondary compounds, altering insect herbivore attack and increasing shoot performance.

Index terms: Induced defenses, plant quality, herbivory

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