Transmission of viruses associated with cytoplasmic and nuclear leprosis symptoms by Brevipalpus yothersi and B. californicus

Abstract

Two groups of viruses cause the citrus disease complex known as leprosis: the cytoplasmic type, of the genera Cilevirus and Higrevirus, and the nuclear type, of the genus Dichorhavirus. It has been shown that the cilevirus Citrus leprosis virus C (CiLV-C) is transmitted by Brevipalpus yothersi. Within the genus Dichorhavirus, CiLV-N is a recently described and distinct species present in Brazil and transmitted by B. phoenicis sensu stricto, whereas the species found in Mexico and Colombia are strains of Orchid fleck virus (OFV-citrus), suspected to be vectored by B. californicus. A study was conducted to determine whether B. californicus and B. yothersi can acquire and inoculate Mexican isolates of CiLV-C and OFV-citrus to sweet and acid citrus species (sweet orange, mandarin, grapefruit, sour orange, Persian lime and Mexican lime) in experiments set up in areas in Mexico with prevalence of the respective viruses. Brevipalpus californicus acquired OFV-citrus and transmitted it to all the citrus cultivars included in the experiment, while B. yothersi acquired CiLV-C and transmitted it only to sweet citrus cultivars (sweet orange, mandarin, and grapefruit). Both mite species were able to become established and reproduce in the experimental plants for nearly a year. This study represents the first experimental evidence of OFV-citrus transmission by B. californicus, as well as evidence that B. yothersi cannot transmit this virus.