Citrus greening disease was caused by fastidious prokaryotic bacterium. A rapid and reliable detection by PCR was developed by CTAB and SS methods (addition of sodium sulphite (SS) to Tris-EDTA) for DNA isolation. DNA from leaf midrib and bark on SS-Tris EDTA method and leaf midrib and veins in CTAB method yielded good amplified products. Regarding time of detection of HLB, strong amplified bands were observed in winter months compared to hot summer months. For the first time, HLB diagnosis adopting PCR using DNA isolated by SS-EDTA method from leaf midrib or bark was being done for bud certification of sweet orange.
Citrus greening, DNA isolation protocols, Huanglongbing tissue source, PCR-diagnosis
