Possible natural betabaculovirus coinfections in Gelechiidae insects from Colombia based on pif gene determination
Abstract: Baculoviruses are pathogens distributed worldwide and classified in four genera (Alpha-, Beta-, Gamma- and Deltabaculovirus) which infect insects many of them considered as pests in agriculture. In view of that, these entities are excellent candidates to formulate bioinsecticides. Tecia solanivora, Phthorimaea operculella and Tuta absoluta are invertebrates belonging to the potato tuber moth complex (Lepidoptera: Gelechiidae) and are considered the main pests in potato and tomato crops. Thus, the characterizations of baculoviruses that can multiply in these insects comprise a relevant focus required to assist in the development of biological control strategies.Considering the above, three betabaculoviruses recovered in Colombia from T. solanivora, P. operculella and T. absoluta respectively were studied to add information with respect to the host range specificity associated with the identity of the per os infectivity complex, constituted by seven proteins encoded in all baculovirus genomes (P74, PIF1, PIF2, PIF3, ODV-e28, ODV-e56 and PIF6) which are essential to support the primary infection into larvae. For this, fragments of the aforementioned seven pif genes were amplified by PCR and sequenced to assist in the virus classification and to study sequence factors related to virus host range. Results showed that three isolates were closely related to the previously described Phthorimaea operculella granulovirus (PhopGV) based on sequence data of six pifs, but surprisingly some amplicons of pif1 also revealed a sequence relationship with Helicoverpa armigera granulovirus (HearGV). This observation could suggest the presence of natural coinfections and/or horizontal gene transfer processes associated to expand the host range.