Fruit leaf roller

The pheromone of another major apple pest in British Columbia, the fruit leaf roller, Archips argyrospilus, has been used successfully to monitor activity and estimate populations so that sprays may be timed more effectively (585). 

It is expected that taxonomically related species which have developed from a common ancestor also exhibit similarity at the pheromone level. An interesting typical representative can be observed in the family Tortricidae. This family includes a multitude of agricultural pest insects such as leaf-rollers and fruit-borers, whose sex pheromones have been exhaustively investigated [33]. Among the four subfamilies in Tortricidae, Tortricinae and Olethreutinae are the major two,... 

In the case of oil sprays a direct relationship has been shown by Cressman and Daw-sey (7) between the amount of oil deposited and insect kill or control. A similar relationship has been shown by Chapman ei al (4) using oil as an ovicide in control of the fruit tree leaf roller. This relationship appears to hold regardless of the emulsifier used. The literature indicates that much attention has been given to the infiuence of emulsifiers on differences in effectiveness of oils. In many cases differences in effectiveness are attributed directly to the influence of the emulsifier. In spite of the various ways in which effects of emulsifiers have been interpreted, it appears that the basic influence of the emulsifier is on amount of oil deposited. 

European red mite Fruit tree leaf roller Apple red bug San Jose scale Scurfy scale... 

Fruit tree leaf roller Pear leaf blister mite Codling moth... 

The ability of male moths to perceive mixtures of geometric isomers with extraordinary acuity was further documented in an investigation of the responses of males of the redbanded leaf-roller and two populations of the European cornborer to isomers of 11-tetradecenyl acetate (21). Redbanded leafroller males were essentially unresponsive to pure preparations of their reported sex pheromone, (Z)-11-tetradecenyl acetate, but were strongly attracted to lures containing up to 8% of the (E)-isomer. Similarly, European cornborer males from Iowa responded maximally when 4% of the (E)-isomer was added to the (Z)-isomer, whereas the New York population was attracted to an isomeric mixture containing about 4% of the (Z )-isomer. Enhanced attraction by a small proportion of the opposite geometric isomer was also demonstrated with males of the oriental fruit moth,... 

The most important enemies of the codling moth are braconid and ichneumon wasps on pupae and fully grown caterpillars. They are not as effective as they are against leaf rollers, however, as the codling moth larva inside the fruit is very well protected against these parasites. 

Table 5.10. Comparison of summer fruit tortrix, apple leaf-roller and fruit tree tortrix.

Leaves rolled up. Cause Strawberry leaf rollers. These green or brown, k" caterpillars mine leaves in the early spring and later form webs and roll leaves as they feed. Leaves may brown and die fruit is deformed. For light infestations, destroy the rolled leaves along with the caterpillars inside. For a very heavy infestation, apply BTK. See the opposite page for an illustration of this pest. 

The suggestion that the sex pheromone composition of the oak leaf roller was dependent to a large extent on diet was made 82,475,476) and refuted 477, 478). It is now generally accepted that the sex pheromone of this tortricid moth species is a specific blend (67 33) of E)- - and (Z)-ll-tetradecenyl acetates 477). It is also accepted that in this species this ratio is not influenced by diet 478). However, the effects of diet on the amount of pheromonal compounds have been suggested for the summer fruit tortrix moth 479), the gypsy moth 480) and the smaller tea tortrix moth 481). 

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