The viral complex associated with mealybug wilt disease of pineapple in Cuba

Abstract

Mealybug wilt of pineapple (MWP) disease has been associated with the infection by a complex of ampeloviruses (Pineapple mealybug wilt-associated virus 1 (PMWaV-1), PMWaV-2, PMWaV-3, PMWaV-4 and PMWaV-5)) (Closteroviridae) and badnaviruses (Pineapple bacilliform CO virus (PBCOV) and Pineapple bacilliform ER virus (PBERV) (Caulimoviridae)). In Cuba, PMWaV-1, PMWaV-2, PMWaV-3 and PBCOV are widespread in commercial pineapple fields, but the association of these viruses with the aetiology of the disease remains unknown. During 2009 to 2012, a survey to detect PMWaV-1, PMWaV-2 and PMWaV-3 by RT-PCR, and PBCOV by non-radioactive Dot Blot hybridization was carried out on samples collected from asymptomatic or MWP symptomatic pineapple plants from 24 commercial fields in 10 provinces and Isla de la Juventud. PMWaV-1, PMWaV-2, PMWaV-3, and PBCOV occurred in simple or mixed infections, whereas PMWaV-2 was the viral species most frequently detected in symptomatic plants. The positive or negative diagnostic results of the RT-PCR to detect PMWaV-2 was more reliably associated with the MWP symptomatic or asymptomatic status of the sampled plants, respectively, than those from PMWaV-1, PMWaV-3 or PBCOV detection techniques. This work discloses the correlation between the infection by PMWaV-2 and the presence of MWP symptoms in Cuba, supporting previous studies indicating the major role of this virus triggering MWP disease.