Characterization of cucumber mosaic virus from Handroanthus heptaphyllus in Brazil

In January 2022 and April 2024, plants of Handroanthus heptaphyllus, designated HP22 and HP24, respectively, exhibiing symptoms of mosaic, leaf blistering, and ring spots were observed in the municipality of Piracicaba, São Paulo state, Brazil. Molecular analysis of plant HP22 revealed the presence of cucumber mosaic virus (CMV, genus Cucumovirus), and phylogenetic analysis classified it into subgroup IA. Additionally, CMV was identified using a plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA) in both plants (HP22 and HP24). The virus of HP22 plant was mechanically transmitted to Handroanthus albus, H. heptaphyllus, H. impetiginosus, Tabebuia heptaphylla, and T. roseoalba plants, a transmission that PTA-ELISA confirmed. Furthermore, transmission was observed from Aphis gossypii to H. heptaphyllus and T. heptaphylla plants. Despite the absence of discernible symptoms, the presence of CMV was confirmed through PTA-ELISA. To the best of our knowledge, this represents the first report on the occurrence of CMV in H. heptaphyllus worldwide.

Keywords:
Bignoniaceae; Cucumovirus ; mechanical; aphid transmission