Bollworm responses to release of genetically modified Helicoverpa armigera nucleopolyhedroviruses in cotton.
Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HaSNPV) has been developed as a commercial biopesticide to control the cotton bollworm, H. armigera, in China. The major limitation to a broader application of this virus has been the relative long time to incapacitate the target insect. Two HaSNPV recombinants with improved insecticidal properties were released in bollworm-infested cotton. One recombinant (HaCXW1) lacked the ecdysteroid UDP-glucosyltransferase (egt) gene and in another recombinant (HaCXW2), an insect-selective scorpion toxin (AaIT) gene replaced the egt gene. In a cotton field situation H. armigera larvae treated with either HaCXW1 or HaCXW2 were killed faster than larvae in HaSNPV-wt treated plots. Second instar H. armigera larvae, which were collected from HaCXW1 and HaCXW2 treated plots and further reared on artificial diet, showed reduced ST(50) values of 15.3 and 26.3%, respectively, as compared to larvae collected from HaSNPV-wt treated plots. The reduction in consumed leaf area of field collected larvae infected with HaCXW1 and HaCXW2 was approximated 50 and 63%, respectively, as compared to HaSNPV-wt infected larvae at 108 h after treatment. These results suggest that in a cotton field situation the recombinants will be more effective control agents of the cotton bollworm than wild-type HaSNPV.
Sun
Xiulian
X
Joint-Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China.
Chen
Xinwen
X
Zhang
Zhongxin
Z
Wang
Hualin
H
Bianchi
Felix J J A
FJ
Peng
Huiyin
H
Vlak
Just M
JM
Hu
Zhihong
Z
D000818:Animals; D004274:DNA, Recombinant / Q000235:genetics*; D005818:Genetic Engineering; D003368:Gossypium / Q000821:virology; D007814:Larva / Q000821:virology; D009036:Moths / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000235:genetics*; D010572:Pest Control, Biological / Q000379:methods*; D016133:Polymerase Chain Reaction; D012604:Scorpion Venoms / Q000235:genetics; D013997:Time Factors
D004274:DNA, Recombinant; D012604:Scorpion Venoms; C065634:AaIT neurotoxin, Androctonus australis