Geographic distribution of mealybug wilt disease of pineapple and genetic diversity of viruses infecting pineapple in Cuba

Abstract

Several species of ampeloviruses and badnaviruses infect pineapple plants around the world. Pineapple mealybug wilt-associated ampeloviruses have been associated with mealybug wilt of pineapple (MWP), the major viral disease threatening this crop. Conversely, infection by the badnaviruses Pineapple bacilliform comosus virus (PBCOV) and Pineapple bacilliform erectifolius virus (PBERV) is asymptomatic. To investigate the status of infection of the pineapple crop in Cuba, a diagnostic survey was developed in commercial areas during the period 2009–2012. Incidence of MWP disease was found in up to 100% of the plants in some fields of Central and Eastern regions of the island. Molecular assays revealed the presence of PMWaV-1 for the first time in the Caribbean basin and PMWaV-2, PMWaV-3, either as mixed infections or in combination with PBCOV throughout the country. Furthermore, they revealed for the first time the presence of PMWaV-2 in Bromelia pinguin L., a plant commonly used in Cuba as hedgerow. Sequence analysis of partial heat shock protein 70h and complete coat protein gene of Cuban isolates of PMWaV-1, -2 and -3 showed nucleotide identities above 97% with cognate sequences of viruses isolated from other countries. This work discloses the presence of a complex of viruses associated with the pineapple crop in Cuba, highlights the potential role of B. pinguin in the PMWaV-mealybug-pineapple pathosystem and makes available diagnostic tools for the detection of viruses affecting pineapple for a seed certified production system in Cuba.