Efeito de inibidores de proteases na atividade enzimática de Coccus viridis em Coffea arabica

The coffee culture in Brazil has much economic importance and relevance in the social sector. One of the possible reductions of its productivity is due to the injury caused by the insect Coccus viridis (cochineal-green). The plants when being injured are able to increase the synthesis of protease inhibitors (PIs) throughout their extension. Studies have shown that insects fed with plants previously sprayed with synthetic inhibitors have their development affected. Thus, the present work aimed to evaluate the effects of synthetic protease inhibitors, benzamidine and berenil, on the intestinal proteolytic activity of C. viridis. Coffea arabica plants were infested with C. viridis nymphs and sprayed with benzamidine and berenil in four different concentrations: 0; 0.25%; 0.5% e 0.75% (p/v). The insect’s biochemical response was evaluated after 24 h of spraying, and the insects were collected. The activity of the serine proteases, trypsin-like (amidasica and esterasica) and chymotrypsin-like esterase, was reduced due to the presence of the inhibitors. The same was obtained in relation to the activity of cysteine proteases.