Codling Moth Information Support System (CMISS) Frequently Asked Questions (FAQ)  

1. Why is this insect called the "Codling Moth"?
   
   "Codling" is a name for elongated, greenish English cooking apples.  The name "Codling Moth" was given to this moth, Cydia pomonella, by B. Wilkes in 1747 in his book "The English Moths and Butterflies" (Book I, Class I, No. 9, P. 5). 
   
   
   
2. What is the Economic Importance of this insect?
   
   The codling moth is the most widely distributed key pest of cultivated pome fruits and walnuts in the world.  Apple being its preferred host, this insect has followed its cultivation around the world.  When uncontrolled, this pest is capable of annually destroying 80- 95% of an apple crop and 40-60% of a pear crop. 
   
   
   
3. Where is the Native Home of Codling Moth?
   
   Codling Moth is native to southeastern Europe. 
   
   
   
4. Can codling moth migrate long distance?
   
   Only a small percentage of codling moth females migrate distances over 100 meters (Widbolz & Baggolini 1959, Whalon & Croft 1985, Prokopy et al. 1991). However, migration distances of 300 meters or more have been noted in arid habitats (White et al. 1973). 
   
   
   
5. How did Codling Moth Spread all over the world?
   
   Due to unrestricted movements of fresh fruits from one country to another in the past, this insect gradually spread to uninfested areas, ultimately becoming cosmopolitan.  It seems that the most common mode of its spread from one place to another has been through the transport of infested fruit and the packing material. Codling moth has remarkable ability to adjust to climatic and trophic conditions. Besides apples, the codling moth can develop on other pome fruits such as pear and quince, on stone fruits such as apricot, plum and peaches as well as on walnuts (Newcomer and Whitcomb 1925), apricot, almond, pecan nuts and pomegranates (Nel 1985). 
   
   
   
6. Briefly describe the biology of codling moth?
   
   The codling moth overwinters as a mature larva beneath tree bark scales or at the base of the tree.  Adults appear about full bloom of Red Delicious apples and eggs are laid on leaves or developing fruitlets.  Eggs hatch in 10 to 25 days, depending upon temperature, and the young larvae move to developing fruit within a few hours, chew through the skin, and burrow into the flesh.  Subsequently, the larva burrows to the fruit core and feeds on seeds.  After 25 to 40 days, the larva is mature, exits the fruit, spins a cocoon, and pupates.  Moths of the second generation emerge two to three weeks later. 
   
   
   
7. Are there Natural Enemies of Codling Moth?
   
   There are several natural enemies of codling moth including birds, spiders, insects, nematodes, bacteria, fungi, protozoa and viruses. 
   
   
   
8. Is Biological Control of codling moth effective?  If not why?
   
   Potential for biological control of codling moth is limited. This is because effective biocontrol agents of this species are lacking. Trichogramma spp. and  Ascogaster quadridentata Wesmael (a braconid wasp) are important parasitoids of egg and egg-larval stages, respectively.  In general, the levels of parasitism of codling moth rarely exceed 15 % in any generation. 
   Soon after hatching (within 24 hours), codling moth neonate larvae bore into the fruit and spend most of their lifespan inside the fruit and as such they are protected from the action of their natural enemies. However, the two most hazardous periods in their life are from egg deposition to penetration of the fruit and during the overwintering phase. Therefore, natural enemies may only be effective in reducing the numbers of codling moth at three specific times during its life cycle, namely the egg stage, newly hatched larvae, and the wintering larvae (MacLellan 1972). 
   
   
   
9. Can codling moth be effectively controlled with Entomopathogens (insect pathogens) like bacteria, fungi, nematodes, protozoa and viruses?
   
   Bacteria and protozoa show little promise for codling moth control. Some entomogenous fungi and nematodes (mainly Steinernema feltiae Filipjev) have shown promising results for the suppression of  overwintering larvae. Their usage, however, may be confined to certain climatic conditions. Codling moth granulosis virus (CpGv) has shown promise for control of neonate larvae. This virus is 10,000 times more virulent than Bacillus thuringiensis for the codling moth neonate. Several field studies have proved its efficacy in reducing codling moth damage and abundance of surviving larvae.  This virus was developed for commercial use in Europe and has been used in the United States under experimental use permits. Development of a cost effective, efficacious CpGv formulation is being pursued by educational institutions and industry. Availability of such a formulation for codling moth would add a highly specific method of remedial control that would not interfere with natural controls of other pests. 
   
   
   
   
10. What are Phenology Models and how can they be used in codling moth management programs?
    
    Phenology models and their uses are explained in detail at the University of California, Davis (USA) website: http://www.ipm.ucdavis.edu/WEATHER/ddconcepts.html#Phenology. 
    Phenology models are generally used to better time insecticide applications, thus improving control and reducing inappropriate use of  chemical controls.  As monitoring becomes a more important component of  intensive IPM programs, phenology models are used to help schedule these activities (reducing control decision errors because of incorrectly timed samples) and reducing monitoring costs. 
    
    
    
11. Is it possible to predict phenology of codling moth?
    
    Insects are cold-blooded animals. Development of their immature stages is keyed to climatic factors, primarily temperature. It is, therefore, possible to predict stage changes from climatic records.  For immature stages of codling moth, growth begins at ca. 10^oC, which can be taken as a common threshold for development of the three stages, namely the eggs, larvae, and pupae.  Each stage has a specific heat requirement to complete development and transform to the next stage.  Research has shown that physiological time models (which require climatic data input) used in combination with pheromone traps catch data provide a reliable system to predict the phenology of the codling moth. These models, however, are limited in predicting the duration of events such as preoviposition, mating, and oviposition. 
    
    
    
12. How can codling moth population be monitored for effective insecticidal treatment?
    
    Codling moth larvae can not be detected until well past time for effective  insecticidal treatment.  Hence, monitoring is aimed at adults.  Formerly, light traps and feeding lures (molasses or beer/wine mixed with water) were the main adult monitoring methods.  More recently, pheromone traps baited with synthetic female sex attractant have been used.  A problem with pheromone traps, however, is that they only attract males and thus give only an indirect measure of female abundance and activity. 
    
    
    
13. How can Pheromone Traps be used for monitoring codling moth population?
    
    There are two ways in which pheromone traps have been used in monitoring codling moth:  (1) counting the number of males caught per week (or cumulatively) to assess the potential of a population for causing economic injury; and (2) using the time of first continuous capture of males as a biological reference (or biofix) point for predicting time of egg hatch and therefore optimum timing of pesticide treatment. 
    
    
    
14. Is pesticide application based on numbers of males captured a reliable method?
    
    Although need for pesticide application based on numbers of males captured seems to be a viable approach in some apple growing areas, it has not proven reliable in other regions.  The reasons may be several, including differences in distances over which males respond to pheromone compared to distances over which females respond to fruit tree stimuli, abundance of virgin females within and without the orchard confines, and meteorological factors affecting male activity and pheromone release. 
    
    
    
15. Is there any reliable method for proper timing of insecticide use against codling moth?
    
    Using the biofix point, in conjunction with number of  degree days accumulated above 10^o C (the threshold for ovary and egg development) since the biofix point, provides a comparatively reliable method for proper timing of pesticide use in orchards that annually require treatment against codling moth. 
    
    
    
16. How can conventional codling moth control tactics based on use of neuroactive insecticides be replaced with environmentally-acceptable control methods?
    
    Replacing conventional control tactics with safer and less disruptive controls requires a combination of tactics against this pest.  The most promising tactics include mating disruption, insect growth regulators, a granulosis virus, biological controls, sterile insect release, and cultural practices, most likely used in various combinations.
    
    
    
17. What is the chemical name of female codling moth sex pheromone?
    
    Sex pheromones of insects are generally composed of more than one compound.  The main component in Codling Moth Sex Pheromone is (E,E) -8,10-dodecadien-1-ol. This compound is commonly called as "Codlemone".   A laboratory synthesized compound of this chemical has shown to be very attractive to the male moths in the field. 
    
    
    
18. Is mating disruption successful in managing codling moth population?
    
    Recently mating disruption has been adopted and tested on a large scale in the western USA.  It was successful in over 95% of the cases.  For more detail, please visit the Website of Areawide Management of the Codling Moth in the Western U.S.A.