Bhaju K. Tamot
Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, Ontario, NIG 2W1, Canada.

Peter M.Gresshoff
Plant Molecular Genetics, Institute of Agriculture, The University of Tennessee, Knoxville, TN 37901-1071, USA.

DOI

ABSTRACT

A DNA sequence for a putative causative organism of citrus greening disease was detected by DNA Amplification Fingerprinting (DAF). Forty arbitrary oligonucleotide primers ranging from five to twelve nucleotides in length were screened for polymorphisms of DNA from greening disease infected and apparently healthy Citrus reticulate Blanco and C. sinensis Osbeck trees. One primer (5GGGTAACGCC 3) generated a pronounced diagnostic band of 200 bp from infected plants which was not present in healthy trees. The diagnostic polymorphic marker band was excised from the silver stained polyacrylamide gel, cloned, and DNA sequenced. The sequence of the DNA amplification product from infected C. sinensis shows homology with bacteria. 200 base pairs are a small fragment of DNA to conclude a possible cause causative organism of Citrus Greening Disease (CGD) yet it shows maximum homology (80%) with bacteria.