Microprojectile plant transformation for sugarcane giant borer pest management

Abstract

Background The sugarcane giant borer, Telchin licus licus, is the major insect pest of crops in northern and northeastern regions of Brazil. This insect has a long life cycle, which lasts about 160-190 days and presenting four major life stages, egg, larvae, pupae and moth [1]. During larval stage, the insect penetrates the plant as soon as they hatch and starts feeding of the stalk, where it stays for a period of 100 to 120 days, approximately. Moreover, it allows the penetration of opportunistic organisms such as fungi and bacteria which ferment the sugarcane juiceand prevents its use in industrial processes. There are no known commercial plants resistant to this insect and the use of chemical pesticides has been inefficient due it sendophytic behavior. The use of biotechnological tools such as RNA interference and expression of proteins with insecticidal activity has allowed developing alternative methodologies for pest control [2]. One of those alternatives is the transformation of plants aimingthe expression of molecules that targets insect survival genes, causing problems in its development and increasing the mortality rate. Proteins with insecticidal activity, as Cry proteins have been used by researches for a long time to increase resistance against agricultural pests [3], since after ingestion of transgenic plants expressing such molecules, the toxin causes an osmotic lysis of midgut cells leading to insect death. The present work focuses on the transformation of elite events of sugarcane to improve plant resistance to the giant borer T. licus licus.