DNA concentration on a microfabricated biochip intended for greenhouse-crop pathogen identification

Many plant diseases affecting greenhouse crops are caused by microbial pathogens, and their identification is a subjective, time-consuming and labor-intensive process. There is a critical need for a more rapid and accurate means of pathogen identification in agriculture since the methods to control diseases are more effective in the early infection stages. We propose to combine microfabrication and MEMS technology as well as electronic DNA hybridization for accurate and rapid identification of plant pathogens. Our ultimate goal is to design, construct, and test a microfabricated biochip for accurate and rapid detection of two fungal plant pathogens, Didymella bryoniae and Botrytis cinerea, based on hybridization of pathogen DNA to immobilized DNA probes on glass substrates. This paper discusses biochip design, fabrication, and assembly, as well as DNA probe concentration by electric field and optical detection. Experiments investigating electronic hybridization of pathogen DNA are underway.