The objective of this experiment was to characterize and quantify responses of Brachiaria brizantha cv. Marandu under different infestation levels of adult spittlebugs of the genus Mahanarva (Hemiptera: Cercopidae). The experiment was carried out in a greenhouse, in Piracicaba, SP. Treatments corresponded to four spittlebugs infestation levels (5, 10, 20 and 40 adults pot-1) plus the control (unifested), distributed in the experimental units (pots) according to a completely randomized design. The study included period of infestation by insects and regrowth of plants. The following response variables were measured: forage yield, root mass and organic reserves. No significant spittlebug effect was observed on regrowth, stubble and root mass of marandu palisadegrass (p > 0.05). The stubble and root mass, as well as the nonstructural carbohydrates concentration, were influenced only during the regrowth period (p < 0.0001). The total nitrogen concentration in stubble and in roots was influenced by the interaction between infestation levels and regrowth period (p < 0.0001 and p = 0.0521).
Brachiaria brizantha; Mahanarva; non structural carbohydrates; organic reserves; root system