Banana Die-Back Virus - a New Virus Infecting Banana in Nigeria

Abstract

Two viruses naturally infect Musa in Nigeria: banana streak badnavirus (BSV) and cucumber mosaic cucumovirus (CMV). During a recent field survey at Ibadan (Nigeria), some severely stunted banana plants (cv. Valery) were found that tested negative for CMV, banana bunchy-top virus, and BSV. The plants had symptoms of leaf crinkling, leaf necrosis, and cigar-leaf die-back. Subsequent suckers from the same mats were progressively more stunted. A 28- to 30-nm isometric virus was purified, and used for the production of antibodies, from the affected plants with (NH4)2SO4 to precipitate the virus. The antiserum (titer of 1:10,000) was used in enzyme-linked immunosorbent assay and immunosorbent electron microscopy to detect the virus. Mechanical inoculation with partially purified virus preparations resulted in stunting and development of pinpoint chlorotic lesions on Vigna unguiculata TVu-76 and symptomless systemic infection of Nicotiana occidentalis. The virus was not mechanically transmissible from N. occidentalis to banana. A serological relationship between this virus, banana die-back virus (BDBV), and tobacco ringspot, tomato ringspot, and cacao necrosis nepoviruses was found. The nematode species around the affected banana plants were isolated: Helicotylenchus multicinctus (Cobb) Golden was the dominant species, low numbers of H. dihystera (Cobb) Sher were present, but no virustransmitting nematodes were found in soil or banana roots. Further studies are needed to determine the mode of spread of BDBV, the implications for banana/plantain production in sub-Saharan Africa, and the safe international movement of germplasm.

Partial characterization and development of sensitive and reliablediagnostic for the detection of cucumber mosaic virus

“…It is the largest fruit crop in India, accounting 33% of the total fruit production, and has great socioeconomic significance. The crop is reported to be infected by a number of pests and diseases including a number of viruses such as Banana bunch top virus (BBTV) (Banerjee et al, 2014), Banana streak virus (BSV) (Baranwal et al, 2014), Cucumber mosaic virus (CMV) (Khan et al, 2011), Banana bract mosaic virus (BBrMV) (Balasubramanian and Selvarajan, 2014), Banana mild mosaic virus (BanMMV) (Teycheney et al, 2007), and Banana dieback virus (BDBV) (Hughes et al, 1998). Vegetative propagation of the banana crop results in continuation of viruses from one generation to the next generation, decreasing the yield of the products and the health of the plants.…”