Biological aspects of Blissus pulchellus Montadon (Hemiptera: Blissidae) regarding the resistance of forage poaceae.

The objective of this study is to evaluate the biological development of the chinch bug, Blissus pulchellus regarding the resistance of the eight forage poaceae. For that, chinch bugs collected from a pasture area, in Boa Vista, Roraima, Brazil, were taken to the Embrapa Roraima Entomology Laboratory for evaluation. The mass breeding of B. pulchellus was carried out in B.O.D., on Urochloa ruziziensis and the biological development evaluation was carried out on eight forage poaceae: Urochloa ruziziensis, U. humidicola, U. brizantha cv. Marandú, U. brizantha cv. Piatã, U. brizantha cv. Paiaguás, Panicum maximum cv. Mombaça, P. maximum cv. Zuri and Andropogon gayanus. The results obtained allowed us to conclude that: a) A. gayanus, P. maximum cv. Zuri and U. humidicola, negatively affect the biology of B. pulchellus; b) A. gayanus, P. maximum cv. Zuri present high and moderate resistance U. humidicola, of the type antibiosis to B. pulchellus and c) Urochloa ruziziensis, U. brizantha cv. Paiaguás and U. brizantha cv. Piatã, have high grade and P. maximum cv. Mombasa and U. brizantha cv. Marandú, less susceptibility to B. pulchellus.