Incidência e prevalência das espécies do Pineapple mealybug wilt-associated virus no banco ativo de germoplasma de abacaxi da Embrapa Mandioca e Fruticultura e em nove estados brasileiros

Abstract

Brazil is the most important center of origin and diversity of pineapple (Ananas comosus (L) Merr.) with the greatest genetic variability from genera concentrated in its territory. The fruit is one of the most appreciated in the world and widely cultivated in the country. The Pineapple mealybug wilt-associated virus (PMWaV) is a virus that infects the pineapple causing disease popularly named Mealybug Wilt of Pineapple (MWP). The virus is transmitted by the mealybugs Dysmicoccus brevipes and D. neobrevipes. The PMWaV belongs to the family Closteroviridae, genus Ampelovirus, has elongated flexuos particles and positive single strand RNA genome. Currently, its belived that the disease is caused by a complex of three virus species, PMWaV-1, PMWaV-2 and PMWaV-3, that differ in the sequence and genome organization. Besides to the direct damage in the plant production, the contamination of wild uncultivated varieties in the Active Germplasm Bank (AGB) at Embrapa Cassava and Fruits is concerning. In addition, there is an absence of information regarding the prevalence of the species in Pineapple commercial field. Hence, the objective of this study was to evaluate the incidence of PMWaV-1, 2,3 in accessions of BAG from Embrapa Cassava and Fruits and nine brazilian states. The results showed that the virus is present in all varieties of A. comosus and A. macrodontes. The PMWaV was not restricted to the genus Ananas, since they were detected in different species of bromeliads. The occurrence of PMWaV in different species of bromeliads is unprecedented and should open space for discussion in relation to its role as a source of spreading the virus. In the commercial pineapple fields samples collected , the predominancy was PMWaV-2, although in two symptomatic samples, only PMWaV-1 was detected. Comparison of sequences obtained showed high conservation only among isolates of the same species. The frequency of plants with mixed infection was high in both surveys.