Expression of the Cry1Ab Protein in Genetically Modified Sugarcane for the Control of <i>Diatraea saccharalis</i> (Lepidoptera: Crambidae)

Abstract

Previously, we genetically modified two Brazilian commercial sugarcane (Saccharum sp.) varieties (SP80-3280 and SP80-1842) for resistance to the sugarcane borer Diatraea saccharalis by co-bombardment transformation with three plasmids: pCIB4421 containing the Bacillus thuringiensis gene cry1Ab regulated by a maize phosphoenol-pyruvate carboxylase promoter, pCIB4426 carrying cry1Ab controlled by a pith promoter, and pHA9 with the neo antibiotic resistance gene. The genetically modified plants were submitted to molecular characterization and insect feeding bioassays. Plants also were screened in the field for insect infestation and had their phenotypic characteristics and quantitative traits evaluated. This study presents evidence that the B. thuringiensis cry1Ab gene can be efficiently expressed in sugarcane plants over an extended growing period, and can confer resistance to the sugarcane borer under field conditions, while not measurably altering numerous material traits of the crop.