characterization. Therefore, further investigation in other regions of the country is
recommended to isolate and characterize native HearNPV isolates.
13.1.2.3 Cydia pomonella
The codling moth, Cydia pomonella (Lep.: Tortricidae) is a well-known agricultural
pest, worldwide. In Iran, it has become the primary pest of apples and is usually
controlled using chemical pesticides. Frequent spraying increases the risk of resistance developing in the pest population (Pluciennik 2013). Among natural enemies
of the pest, a Betabaculovirus has high potential for application as a biocontrol agent
of codling moth (Miletic et al. 2011).
The Cydia pomonella granulovirus (CpGV) is an effective biological control
agent against codling moth, especially for organic apple production. The isolation of
CpGV is difficult because infected larvae rupture and are not visible on the trees. In
2002, 11 isolates of CpGV (designated I1, I7, I8, I15, I22, I28, I30, I66, I67, I68, and
I70) were collected from northwest and northeast Iran (Rezapanah et al. 1998). Light
and electron microscopy studies confirmed the identity of granulovirus in the
codling moth populations. Then, these isolates were characterized using bioassays
and endonuclease profile analysis (RFLP) (Rezapanah et al. 2008). The isolated
CpGVs showed different biological and molecular characteristics which indicated
there were various genotypes of this virus in the Iranian strains (Eberle et al. 2009;
Rezapanah et al. 2008). Most interestingly, it was shown that one of the isolated
CpGVs, known as CpGV-I12, was able to overcome the CpGV resistance issue
which occurred in Germany and France (Berling et al. 2009a, b; Eberle et al. 2008).
The CpGV-I12 showed great efficacy in laboratory bioassays against all larval
instars of a resistant codling moth strain CpR, which has a 100-fold reduced
susceptibility to the commercially used isolate of CpGV-M (Berling et al.
2009a, b). Therefore, CpGV-I12 has been suggested as a promising alternative
microbial control agent of this insect pest. Further studies should be undertaken to
isolate and characterize more isolates of CpGV from the country. The CpGV isolates
found in northwest Iran make an important contribution to the known diversity of
CpGV strains.
13.1.2.4 Plutella xylostella
The diamondback moth (DBM), Plutella xylostella (Lep.: Plutellidae) is one of the
most important pests of crucifers in the world. Fahimi et al. (2008a) surveyed the
sensitivity of 2nd, 3rd, and 4th instar larvae, as well as eggs of P. xylostella to
Memestra brassicae nucleopolyhedrosis virus (MbNPV) in laboratory conditions.
The leaf surface was infected with viral suspensions containing 47.86 OB/mm
2 .
There was no significant difference in mortality of DBM eggs, or 1st and 2nd instar
larvae. However, there was a significant difference in 3rd instar larvae mortality. The
13 Insect Pathogenic Viruses, Microsporidians and Endosymbionts
511
recommended to isolate and characterize native HearNPV isolates.
13.1.2.3 Cydia pomonella
The codling moth, Cydia pomonella (Lep.: Tortricidae) is a well-known agricultural
pest, worldwide. In Iran, it has become the primary pest of apples and is usually
controlled using chemical pesticides. Frequent spraying increases the risk of resistance developing in the pest population (Pluciennik 2013). Among natural enemies
of the pest, a Betabaculovirus has high potential for application as a biocontrol agent
of codling moth (Miletic et al. 2011).
The Cydia pomonella granulovirus (CpGV) is an effective biological control
agent against codling moth, especially for organic apple production. The isolation of
CpGV is difficult because infected larvae rupture and are not visible on the trees. In
2002, 11 isolates of CpGV (designated I1, I7, I8, I15, I22, I28, I30, I66, I67, I68, and
I70) were collected from northwest and northeast Iran (Rezapanah et al. 1998). Light
and electron microscopy studies confirmed the identity of granulovirus in the
codling moth populations. Then, these isolates were characterized using bioassays
and endonuclease profile analysis (RFLP) (Rezapanah et al. 2008). The isolated
CpGVs showed different biological and molecular characteristics which indicated
there were various genotypes of this virus in the Iranian strains (Eberle et al. 2009;
Rezapanah et al. 2008). Most interestingly, it was shown that one of the isolated
CpGVs, known as CpGV-I12, was able to overcome the CpGV resistance issue
which occurred in Germany and France (Berling et al. 2009a, b; Eberle et al. 2008).
The CpGV-I12 showed great efficacy in laboratory bioassays against all larval
instars of a resistant codling moth strain CpR, which has a 100-fold reduced
susceptibility to the commercially used isolate of CpGV-M (Berling et al.
2009a, b). Therefore, CpGV-I12 has been suggested as a promising alternative
microbial control agent of this insect pest. Further studies should be undertaken to
isolate and characterize more isolates of CpGV from the country. The CpGV isolates
found in northwest Iran make an important contribution to the known diversity of
CpGV strains.
13.1.2.4 Plutella xylostella
The diamondback moth (DBM), Plutella xylostella (Lep.: Plutellidae) is one of the
most important pests of crucifers in the world. Fahimi et al. (2008a) surveyed the
sensitivity of 2nd, 3rd, and 4th instar larvae, as well as eggs of P. xylostella to
Memestra brassicae nucleopolyhedrosis virus (MbNPV) in laboratory conditions.
The leaf surface was infected with viral suspensions containing 47.86 OB/mm
2 .
There was no significant difference in mortality of DBM eggs, or 1st and 2nd instar
larvae. However, there was a significant difference in 3rd instar larvae mortality. The
13 Insect Pathogenic Viruses, Microsporidians and Endosymbionts
511