The isolation and genetic characterisation of a South African strain of Phthorimaea operculella granulovirus, PhopGV-SA

The potential of novel African isolates of Phthorimaea operculella granulovirus for the control of Tuta absoluta

“…Though Tu2.11 and Ken13 belonged to the same egt group, these two viruses were not identical as indicated by polymorphism of the gran gene region. These findings expand previous analyses of the Tunisian reference isolate PhopGV‐1346, which had previously been classified as egt I type (Jukes et al., ). This classification of the novel African isolates was confirmed by DNA sequencing of the PCR products followed by phylogenetic analyses (Figure ).…”

“…Also based on sequence length and amino acid sequence alignment, the isolates could be grouped according to the proposition by Jukes et al. (). The predicted amino acid (aa) sequence length of egt II group including Ken13 and Tu2.11 is 450 aa, whereas that of group III (Tns16, Tu1.11 and Ym14) is 361 aa.…”

“…Jukes et al. () identified five different egt gene groups for PhopGV isolates, three of them (egt group I to III) occur in Tunisian PhopGV isolates alone, underscoring the high genetic variability of African PhopGV isolates.…”

“…Full genome sequences of PhopGV isolates have been determined for the Tunisian isolate PhopGV‐1346 and the South African isolate PhopGV‐SA (Jukes, Motsoeneng, Knox, Hill, & Moore, ; Taha, Nour‐El‐Din, Croizier, López Ferber, & Croizier, ). Genetic variability of PhopGV isolates is demonstrated by endonuclease restriction digestion of the genomic DNA (Espinel‐Correal et al., ; Lery, Abol‐Ela, & Giannotti, ) as well as PCR analysis of specific genome areas (Carpio et al., ; Jukes, Knox, Hill, & Moore, ). To distinguish between the different PhopGV isolates, the nucleotide sequence variability of the ecdysteroid UDP‐glucosyltransferase ( egt ) gene has been applied as a useful marker.…”

“…Sequence comparison of different PhopGV isolates revealed three egt types; namely egt I, egt II and egt III, which show different sizes of the egt ORF of 1,353 bp, 1,305 bp and 1,086 bp, respectively. Two additional egt gene types were identified as egt IV and egt V with 1,092 bp and 861 bp in length, respectively (Carpio et al., ; Jukes et al., ). Another highly conserved gene used for isolate and species identification is the highly conserved granulin gene, which is homologous to the polyhedrin gene of the genus Alphabaculovirus and encodes the highly conserved matrix protein of the baculovirus occlusion body (OB; Herniou & Jehle, ).…”