Gene transcript changes associated with Bemisia tabaci biotype B -induced tomato irregular ripening disorder identified using microarray technology and Q-RT-PCR

Tomato irregular ripening is a disorder manifested in the fruit as a result of silver leaf whitefly (otherwise known as the B biotype of Bemisia tabaci) feeding on leaf phloem of tomato. This physiological disorder has significant economic impact in commercial tomato production; however, little is known about the molecular basis for the phenomenon. Microarray technology was used to screen for changes in tomato transcript abundances associated with the onset of this physiological disorder. Plants grown in identical growth chambers were either infested with whitefly or left uninfested as controls. Plants were infested with five whiteflies per leaf at the 5 to7 true leaf stage and grown for an additional 45 and 65 days. At these times, samples including immature leaves, mature leaves, roots, stems, flowers and fruit were harvested and total RNA was isolated and used to probe tomato microarrays obtained from the Center for Gene Expression Profiling (CGEP) at the Boyce Thompson Institute at Cornell University. Transcripts identified as either increasing or decreasing in abundance as a result of whitefly infestation were identified and results were verified using Q-RT-PCR. Data will be discussed with respect to known stress/defense responsive and ethylene responsive genes.