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Analysis of several Colombian Phthorimaea operculella granuloviruses isolated from Tecia solanivora: Detection of a new variable region in the PhopGV genome

Authors:
Insect Pathogens and Insect Parasitic Nematodes
IOBClwprs Bulletin Vol.31, 2008
p. 83
Analysis
of
several
Colombian
Phthorimaea operculella
granulovirus
isolated
from
Tecia solanivora: Detection
of
a new
variable
region in
the
PhopG
Vgenome
Xavier
Lery',
Laura
VillamizarzCarlos Espineli,
Jean
-Louis Zeddarrr',
Alba
Marina
Cotesi, Miguel Lopez-Ferber"
IIRD. Centre de Recherche. 30380 St Christol-les-Ates, France; 2CORPOICA, Km 14 via
Mosquera. Bogota. Colombia; 3IRD, PUCE. Quito. Ecuador; ./LGEI. Ecole des Mines, Ales,
France
Ahstr
act: Five isolates of Phthorimaea opercu/ella granulovirus (PhopGV). obtained from Tecia
solanivora larvae sampled from three different regions of Colombia were studied. One isolate was
obtained from an infected larva collected in the north-east near the frontier with Venezuela. one from
the south-west near the frontier of Ecuador and the three others from the center of Colombia. They
were amplified on larvae of T. so/anivora reared in laboratory conditions. Isolates were characterized
using 12 specific restriction endonucleases and the amplification by PCR of the four variable regions
already mentionned for PhopGV. using specific set of primers. The results indicated differences
between the strains. The three isolates from the center part of Colombia present the same profiles, and
the Iwo others present submolar bands either with REN or with PCR analysis. The Colombian isolates
were compared with several PhopGVs originated from Peru. Ecuador and Tunisia and isolated from P.
operculella. T. so/anivora and S. tangolias. Using the 4 set of primers. the three isolates from the
center part of Colombia present a profile specific to T. solanivora isolates. In the two other isolates,
the submolar bands are the same than the ones found inP. apercu/ella profiles. indicating the presence
in the genome of at least 2 different profiles. A new variable region was detected in the 90-91 gene
region using another set of primers. With this set of primers. a 630 bp band appears. different from the
789 bp band usually found with the other PhopGV strains. The sequence of this part of the genome
indicates a deletion in the repetitive part of the 90-91 genes. This deletion appears to be a specific
modification only found in viral strains obtained from T. so/anivora in Colombia.
83
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Bulletin
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srop Vol. 31, 2008
Intemational Organization for Biological
and
IntegratedControl
of
Noxious Animals and Plants
Organisation Intemationale de Lutte Biologique et Integree contre les Animaux et les Plantes Nuisibles
West Palaearctic Regional Section /Section Regionale Ouest Palearctique
... DNA fragments were stained with SYBR ® gold (Invitrogen) and visualized on a UV transilluminator (Chemi-Doc, Bio-Rad Laboratories, CA, USA), and the fragment sizes were estimated using 1 Kb Plus DNA ladder (Invitrogen). Restriction patterns of the viruses were analysed for the presence or absence of specific bands, comparing with the restriction pattern of a P. operculella granulovirus from Peru, coded as VG006(Léry et al., 2008). ...
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