Development of transgenic sugarcane strains overexpressing peptidase inhibitors for resistance to insect Migdolus fryanus

Abstract

Sugarcane (Saccharum spp.) represents an important economic activity of brazilian agroindustry, being the country the largest producer of sugar and ethanol derivative from sugarcane. However, Brazil still suffers damage that reach 10% in sugar and alcohol sector, owing to insect pests attack. The Migdolus fryanus insect has caused great losses infesting sugarcane plantations, because the larvae, owing to dietary habits, attack the plants root system and can destroy it completely, reducing productivity. The inefficiency of pest control methods stimulates the performance of studies involving new approaches such as the use of inhibitors against peptidases from insects to generate resistant plants, which have already been successfully developed in research. Thus, we intend, in this project, identify sugarcane cystatins with specific inhibitory activity against M. fryanus digestive cysteine peptidases, for the further generation of resistant plants by peptidase inhibitor overexpression. For this purpose, the respective cystatin genes will be introduced in sugarcane using genetic transformation mediated by Agrobacterium tumefaciens and biolistic method. Biological assays will be performed using the recombinant inhibitors of cysteine peptidases incorporated into artificial diets for evaluation of insect development. Thus, we expected that this study can contribute to the establishment of future sugarcane varieties resistant to Migdolus fryanus attack. (AU)