Anticarsia gemmatalis represents a relevant factor for lowering soybean and other legumecropproductivities. Protease inhibitors affectprotein degradation and reducethe availability of amino acids, impairing the development and survival of insect pests. To evaluate the possible use of proteinaceous protease inhibitors in the management of this pest, the activities of midgut proteases andthe growth and development of A. gemmatalis larvae exposed to soybean Bowman-Birk trypsin-chymotrypsin inhibitor (SBBI) and soybean Kunitz trypsin inhibitor (SKTI) were determined. The survival curves obtained using Kaplan-Meier estimators indicated that SKTI and SBBI stimulated larval survival. However, the development of A. gemmataliswas delayed, and prepupal weight decreased in the presence of both inhibitors. The results showed that SKTI and SBBI inhibited the trypsin-like and total proteolytic activities of larvae on the 12th day after eclosion. On the 15th day after eclosion, larvae exposed to SKTI increased the activities of trypsin and total proteases. Although SKTI and SBBI did not affect the survival of the insect, they had effects on midgut proteases in a stage whereinA. gemmatalis fedvoraciously, increased the larval cycle, and decreased prepupal weight. These findings provide baseline informationabout the potential of proteinaceous protease inhibitors to manage the velvetbean caterpillar, avoiding chemical pesticides.
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