Title : Diagnostics tools for detection of citrus yellow mosaic virus (CYMV) & citrus greening bacterium (CGB) in sweet orange by multiplex pcr
Citrus is one of the most economically important fruit crops in India. Commercially grown citrus includes sweet orange, acid lime and mandarin. Citrus Yellow Mosaic (CYMV), a viral disease and citrus greening bacterium (CGB), a bacterial disease are the two most important diseases that are impending fruit production through the world. Symptoms include yellow shoots, blotchy mottling leaves, corky veins, twig dieback, smaller or lopsided fruits with aborted seeds, root degradation and tree decline HLB affects all commercial citrus varieties and a source of genetically resistant germplasm remains unknow. Despite these efforts, the most effective way to control HLB would be the replacement of susceptible citrus varieties by HLB-resistant plants. However, no resistant trees or scion-rootstock combinations have been identified so far. Citrus genetic transformation via the introduction of a single trait is an opportunity for improvement of citrus varieties, maintaining their genotypic and phenotypic characteristics. Different genetic strategies have been tested to obtain HLB-resistant citrus varieties.
A method of multiplex polymerase chain reaction (PCR) was developed for the simultaneous detection of Citrus yellow mosaic virus (CYMV) and citrus greening bacterium, Candidatus Liberibacter asiaticus (CLa) from sweet orange trees. Initially total DNA from individual CLa and CMBV infected citrus plants were mixed infected field sample for both pathogens were detected by Multiplex PCR. Using multiplex PCR two different fragments of 1024 bp and 451 bp specific to CYMV and CGB respectively were simultaneously amplified. The consistent result of multiplex PCR was compared with Simplex PCR for detection of each pathogen. The Multiplex PCR method developed in the present investigation proved to be highly sensitive, economic and reliable methods for detection of citrus greening bacterium (CGB) and the Citrus yellow mosaic virus (CYMV) in citrus trees from the orchards. The technique should prove highly useful in disease surveys, nursery certification and quarantine applications. A method of multiplex polymerase chain reaction (PCR) was developed for the simultaneous detection of Citrus yellow mosaic virus (CYMV) and citrus greening bacterium, Candidatus Liberibacter asiaticus (CLa) from sweet orange trees.