Induced resistance in soybean cultivars following injury by Spodoptera eridania (Cramer) (Lepidoptera: Noctuidae)

Abstract

Induced resistance in soybean plants triggered by insect herbivory may provide an efficient defense against multiple future factors, such as the attack of larvae of Spodoptera eridania (Cramer) (Lepidoptera: Noctuidae), not reducing plant development when stressing factors are absent. Thus, this research project will test the hypothesis that plants of soybean cultivars injured by S. eridania larvae induce resistance to subsequent feeding and development of larvae from this species; if this phenomenon is associated to the increase of concentration of the oxidative enzymes peroxidase, polyphenol oxidase, superoxide dismutase, catalase, and trypsin inhibitor; if the increase of enzymatic activities promotes increase of production of the flavonoids rutin, daidzin, hesperidin, and isoquercitrin; and if the resistance induction to the larvae causes lower vegetative growth in plants. The experiment will be set up in a completely randomized design and consisted in injured plants (treatment) and uninjured plants (control) using the soybean cultivars IAC 100 (resistant) and BRSGO 8360 (susceptible). The experiment will evaluate nutritional indexes, leaf area consumed, oxidative enzymes, trypsin inhibitor, flavonoids and biometric parameters in plants of the soybean cultivars following injury by S. eridania larvae. We expect the results obtained in this experiment may contribute to better understanding of the complex process of resistance induction in soybean against herbivory by larvae of S. eridania, its relation with production of oxidative enzymes, proteinase inhibitor and flavonoids assessed, as well as to vegetative growth of the plants.