S-36. Identification and detection of the Badnavirus infecting black pepper (Piper nigrum L) in India
Abstract
Black pepper, obtained from dried berries of Piper nigrum L., is an important spice of international commerce for India. The crop is mainly grown in the southern states of Kerala and Karnataka. The productivity of the crop is considerably low due to many biotic stresses, including viruses. Among the viruses, association of Cucumber mosaic virus (CMV) and a Badnavirus were reported from India. The exact taxonomic identity of the Badnavirus remained unaddressed. Hence in the present study, identification, variability and a PCR based detection for the virus was developed. A portion of viral genome corresponding to open reading frame (ORF) I and III of the Badnavirus infecting black pepper collected from different agro-climatic regions in India were cloned and sequenced. The sequenced region of ORF I contained 694 to 710 bases while that of ORF III contained 597 to 600 bases in different isolates. Sequence analysis and phylogram confirmed that the identity of the virus as a strain of Piper yellow mottle virus (PYMoV). Further, high level of sequence conservation (=95%) was noticed in the sequenced region of both ORF I and ORF III in different isolates collected from different regions. A reliable protocol was developed for the isolation of DNA from black pepper and PCR for detection of the virus. As black pepper is vegetatively propagated through stem cuttings, the detection method can be used in certification programme to produce virus-free plants.
