Genetic characterisation of viruses infecting sweetpotato in South Africa
Sweetpotato is an important food crop in rural communities of South Africa due to its nutritional content, including β carotene (provitamin A) from the orange-fleshed sweetpotato. Sweetpotato is also popular among farmers with limited resources, playing an important role as a food security crop. It is also grown commercially for the fresh and export markets. Potyviruses, such as Sweet potato feathery mottle virus (SPFMV) and a Geminivirus, Sweetpotato leaf curl virus (SPLCV), are threatening the production of sweetpotato in South Africa. NCM-ELISA and published reverse transcription polymerase chain reaction (RT-PCR) and PCR methods were used to detect SPFMV and SPLCV. The cloned coat protein genes of SPFMV [russet crack (RC) and common (C) strains)] and SPLCV were sequenced. RT-PCR confirmed the occurrence of SPFMV, and distinguished between its different strains (RC and C) in samples collected from different provinces of South Africa. Sequencing and phylogenetic analysis also confirmed that both the RC and C strains of SPFMV are present, and could spread to other provinces of the country. The Geminivirus SPLCV isolates were also correctly identified, and are related to those reported in other parts of the world.
Mulabisana, J., Cloete, M., Mabasa, K., Laurie, S.M., Oelofse, D. and Rey, M.E.C. 2015. Genetic characterisation of viruses infecting sweetpotato in South Africa. Acta Hort. (ISHS) 1105:155-162
SPFMV, SPLCV, NCM-ELISA, RT-PCR, PCR, sequencing and phylogenetic analysis