Graft transmission and confirmation of Candidatus Liberibacter asiaticus using PCR with species specific primers

Citrus greening (Candidatus Liberibacter asiaticus) is the most devastating disease of citrus with no known cure and an uncertain disease latency period. Biological indexing is the oldest and important method for detection of plant diseases including citrus greening disease, and it also aids in understanding the disease’s epidemiology. The current study was conducted to test the transmission of greening disease using different indicator plants. Seven indicator plants (Kinnow, PAU Kinnow-1, Daisy, Musambi, Kagzi Lime, Baramasi Lemon and Limequat) were budded with ten cultivars (Kinnow, Daisy, W. Murcott, Musambi, Jaffa, Blood Red, Reo Red, Kagzi Lime, Baramasi lemon and Limequat). The cultivars viz., Kinnow, Daisy, Musambi and Kagzi Lime were found to be the best indicator plants for indexing of greening disease. Positive plant samples were also tested with PCR using two primer pairs, CGB F/R and OA1/OI2c, for more accurate disease confirmation.