Effects of soybean Kunitz trypsin inhibitor on the cotton boll weevil (Anthonomus grandis)

• Published in: Phytochemistry (Oxford) Vol. 65; no. 1; pp. 81 - 89
• Main Authors: Franco, O.L, Dias, S.C, Magalhaes, C.P, Monteiro, A.C.S, Bloch, C. Jr, Melo, F.R, Oliveira-Neto, O.B, Monnerat, R.G, Grossi-de-Sa, M.F
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 2004
• Subjects: Agronomy. Soil science and plant productions; Animal Feed; animal morphology; animal proteins; Animals; Anthonomus grandis; Biological and medical sciences; bovine pancreatic trypsin; Cattle; Coleoptera - drug effects; Coleoptera - enzymology; cotton boll weevil; Digestive System - enzymology; Dose-Response Relationship, Drug; enzyme inhibition; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Glycine max; grain crops; insect pests; Larva - drug effects; Larva - growth & development; midgut; morphogenesis; mortality; Pest animals; Pest resistance; phytophagous insects; plant pests; plant proteins; Pupa - drug effects; Pupa - growth & development; purification; Serine Endopeptidases - metabolism; serine proteinases; soybean kunitz trypsin inhibitor; soybeans; Survival Analysis; Trypsin - metabolism; Trypsin Inhibitor, Kunitz Soybean - pharmacology; trypsin inhibitors; Trypsin Inhibitors - pharmacology; Varietal selection. Specialized plant breeding, plant breeding aims; Coleoptera; Insecta; Soybean; Cotton; Serine proteinases; Pest; Pest management; Dicotyledones; Angiospermae; Transgenic plant; Inhibition; Bioassay; Kunitz inhibitor; Serine endopeptidases; Enzyme; Mortality; Glycine max; Peptidases; Kunitz trypsin inhibitor; Leguminosae; Larva; Arthropoda; Anthonomus grandis; Hydrolases; Pest resistance; Spermatophyta; Curculionidae; Invertebrata
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2003.09.010

The cotton boll weevil, Anthonomus grandis, is an economically important pest of cotton in tropical and subtropical areas of several countries in the Americas, causing severe losses due to their damage in cotton floral buds. Enzymatic assays using gut extracts from larval and adult boll weevil have demonstrated the presence of digestive serine proteinase-like activities. Furthermore, in vitro assays showed that soybean Kunitz trypsin inhibitor (SKTI) was able to inhibit these enzymes. Previously, in vivo effects of black-eyed pea trypsin chymotrypsin inhibitor (BTCI) have been demonstrated towards the boll weevil pest. Here, when neonate larvae were reared on an artificial diet containing SKTI at three different concentrations, a reduction of larval weight of up to 64% was observed for highest SKTI concentration 500 micromolar. The presence of SKTI caused an increase in mortality and severe deformities of larvae, pupae and adult insects. This work therefore represents the first observation of a Kunitz trypsin inhibitor active in vivo and in vitro against A. grandis. Bioassays suggested that SKTI could be used as a tool in engineering crop plants, which might exhibit increased resistance against cotton boll weevil.