Trypsin inhibitor activities as defense mechanism of sengon (Falcataria moluccana) against pest attacks

Abstract

Abstract Sengon (Falcataria moluccana) plantation always suffers from a serious attack of stem borer, which is called Boktor (Xystrocera festiva Pascoe). This research aimed to investigate the presence of anti-pest substances, i.e. trypsin inhibitor on each part of a sengon tree, which might serve as a defense mechanism against the pest. Healthy and severely attacked sengon trees from Cianjur, Solomon, and Kediri provenances were sampled for their leaves, barks, and woods. Trypsin inhibitor activity from each sample was assayed using synthetic enzyme and substrate in a spectrophotometer. Data were analyzed under Complete Randomized Design, using SPSS 11.5. Different provenances, tree condition, and part of tree gave significant effects on trypsin inhibitor activity. Healthy trees had a higher Trypsin Inhibitor Activity (TIA) value compared to the pest-infected tree. The sengon tree tissue that had the highest TIA is the bark from healthy trees of Solomon provenance, with a value of 730.0403 TIU/mg. Obviously the bark is the first defense against the stem borer pest.