Prevalence of potato viruses on potato (Solanum tuberosum L.) grown in the Western Highlands of Cameroon

Abstract

Solanum tuberosum L. is considered by the Food and Agricultural Organization as one of the alternative food crops that can help to fight against hunger in the world. However, this crop species is subject to numerous attacks, among which viruses are responsible for causing considerable losses of crop quality and yield. The objective of this study was to detect Potato virus X (PVX), Potato virus Y (PVY) and Potato leaf roll virus (PLRV) and to determine the prevalence of these viruses in potato farms in the Western Highlands of Cameroon. For this purpose, 600 symptomatic and 200 asymptomatic leaf samples were collected from 20 potato fields distributed in low (Ø <1800 m) and high (Ø ≥1800 m) altitudes (300 symptomatic and 100 asymptomatic per altitude). These leaf samples were collected from 5 potato varieties (Banso, Cipira, Désiré, Dosa and Jacob2005), and then subjected to the Double Antibody Sandwish Enzyme Linked Immunosorbent Assay (DAS-ELISA) test. Results showed that 50.5% of the leaf samples tested positive to at least one of the targeted viruses. These viruses were detected in single, double and triple infections in potato varieties collected in the different localities. The overall infection rates were 42.3%; 21.3% and 5.3% for PVY, PLRV and PVX respectively. Asymptomatic leaf samples showed positive reactions to viruses (PVX, PVY and PLRV) at a rate of 17.5%. Meanwhile, 38.7% of symptomatic samples tested negative to these viruses (PVX, PVY and PLRV). Symptoms alone are not sufficient to declare that a potato plant is infected by a virus. A multiplicity of test methods may be required to detect various potato viruses, given that some of asymptomatic virus infections may be due to different viruses at different concentrations and may be due to low virus titer below the detection limits of DAS-ELISA. • Potatoes grow in the agro-ecological zone of the Western Highlands of Cameroon are infected by PVX, PVY and PLRV. • The DAS-ELISA test is one of the best technique used to detect the presence of potato viruses. • Asymptomatic leaf samples can be infected to viruses; meanwhile symptomatic samples can be tested negative.