Detection of the Asian Strains of the Greening BLO by DNA-DNA Hybridization in Indian Orchard Trees and Malaysian Diaphorina citri Psyllids

Abstract

A BLO DNA fragment (In 2.6) from a Poona (India) strain of the greening organism (GO) has been cloned and used as a probe for the detection of the BLO in field trees and psyllids in India, in February 1992. Fifty three samples from Orissa, Rajasthan, Uttar Pradesh, and Myssore areas, were tested by dot hybridization using a2Plabelled probes. Most of the samples were also examined by electron microscopy (EM) for the presence or absence of the BLO. The results show that DNA-DNA hybridization is able to reliably detect the GO in all regions of India with a sensitivity at least equivalent to that of EM.