Survey for CMV in field samples ofMusaspp. in southern Nigeria

Symptomatic and asymptomatic plantain and banana (Musa spp.) leaf samples were collected in 1998, 1999, 2000 and 2004 to determine the frequency of infection by Cucumber mosaic virus (CMV) in 11 major plantain- and banana-growing states of southern Nigeria in which virus symptoms had been reported. Of 996 Musa plants sampled, 641 (66.4%) were infected with CMV, as determined by dot blot immunoassay and ELISA. CMV occurred in 64 out of 84 villages and in all the states sampled. Incidences of CMV in the leaf samples were variable in survey years, ranging between 16.7 and 100%. Major virus-induced symptoms were interveinal chlorosis and chlorotic streaks, observed in 29.3 and 26.7% of the total number of surveyed Musa plants. Low incidences of general leaf chlorosis, leaf crinkling/puckering, vein thickening and chlorotic flecking between 1.4 and 10.5% were also observed. Multiple viral infections in the total number of surveyed Musa plants accounted for 5.4% while 7.9% were asymptomatic. CMV induced some of the viral infections on Musa plants in southern Nigeria.