Rapid Emergence of Baculovirus Resistance in Codling Moth Due to Dominant, Sex-Linked Inheritance
S. Asser-Kaiser,1
E. Fritsch,2
K. Undorf-Spahn,2
J. Kienzle,3
K. E. Eberle,1
N. A. Gund,3,4
A. Reineke,4
C. P. W. Zebitz,3
D. G. Heckel,4*
J. Huber,2
J. A. Jehle1*
Insect-specific baculoviruses are increasingly used as biological control agents of lepidopteran pests in agriculture and forestry, and they have been previously regarded as robust to resistance development by the insects. However, in more than a dozen cases of field resistance of the codling moth Cydia pomonella to commercially applied C. pomonella granulovirus (CpGV) in German orchards, resistance ratios exceed 1000. The rapid emergence of resistance is facilitated by sex-linkage and concentration-dependent dominance of the major resistance gene and genetic uniformity of the virus. When the gene is fixed, resistance levels approach 100,000-fold. Our findings highlight the need for development of resistance management strategies for baculoviruses.
1 Laboratory of Biotechnological Crop Protection, Department of Phytopathology, Agricultural Service Center Palatinate (DLR Rheinpfalz), Breitenweg 71, 67435 Neustadt an der Weinstrasse, Germany.
2 Institute for Biological Control, Federal Biological Research Center, Heinrichstrasse 243, 64287 Darmstadt, Germany.
3 Institute of Phytomedicine, University of Hohenheim, 70593 Stuttgart, Germany.
4 Department of Entomology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany.
* To whom correspondence should be addressed. E-mail: johannes.jehle{at}dlr.rlp.de (J.A.J.); heckel{at}ice.mpg.de (D.G.H.)
