Tree Fruit Research & Extension

New Insecticides for Apple and Pear IPM

Calpyso (thiacloprid)- Calypso is next in the line of neonicotinyls registered on apples and pears that has lepidopteran activity, also primarily limited to codling moth. Calypso and Assail are very similar products, with regards to toxicity and efficacy against most pests. Practical resistance management would suggest that growers should limit the number of neonicotinyl applications in a season, so care must be taken when adding Calypso to a program that is already using Provado, Actara or Assail. Calypso also has a more restrictive label than Assail. For example, Calypso has a 30 day PHI, applications are not allowed between pink and petal fall in both pears and apples, 100 ft buffer for aerial applications near rivers and streams, and several endangered species restrictions (see label).


Lepidopteran pests
Codling moth – Calypso appears to have a high degree of activity against codling moth, with expected results very similar to Assail. Calypso also has the same ovicidal properties as Assail. Our data suggest that growers should be able to replace a Guthion spray with a Calypso spray and not notice a significant decrease in control. Both Assail and Calypso will allow growers more flexibility with worker reentry intervals than Guthion. Rotating Calypso with Assail cannot be considered resistance management as these products belong to the same class of chemistry and have the same mode of action.

Leafrollers – We have not tested Calypso in the field against leafrollers. However, laboratory bioassays indicate that Calypso has only low toxicity to neonate larvae.

Lacanobia fruitworm – We have not tested Calypso in the field against Lacanobia. However, laboratory bioassays indicate that Calypso has only low toxicity to neonate larvae.


Indirect/secondary pests
Calypso is a good leafhopper material and definitely has campylomma activity, but perhaps not as strong as Assail. However, a preliminary Calypso label restricts use between pink and petal fall. Make sure to follow label restrictions when applying Calypso during this time period. Calypso has the same activity as Assail against the green aphid complex and rosy apple aphids. The earlier it can be applied against rosy apple aphids the better. Calypso does not have activity against woolly apple aphids.


Pear pests
Calypso is effective against pear psylla and grape mealybug, like Actara, Provado, and Assail, and also can be used for codling moth control, like Assail. Calypso has been shown in field tests to control high densities of pear psylla in prebloom, petal fall, and summer applications, much the same as the other neonicotinyls. In field tests against grape mealybug, at all appropriate timings, Calypso also significantly reduced the populations, but not to the same degree as the other three neonicotinyls. Pest mortality was increased when oil was added to Calypso applications, and Calypso appears to have the same negative effects against campylomma as the other neonicotinyls.

In field trials against codling moth, Calypso successfully controlled high populations of codling moth, comparable to both Guthion and Assail. However, use of this material against codling moth in pear comes with the same caveats as with Assail; it may be more important to direct this class of insecticides at pear psylla rather than codling moth, where there are other effective alternatives.


Beneficial arthropods
Given the efficacy against codling moth, the tendency may be to use multiple applications in a season, however both a 2- and 4-spray program have caused detectable mite flareups, some quite severe. At least some of this effect is attributable to a deleterious effect on predatory mites. This effect has been quite consistent in orchards with previous history of mite problems, thus risk of mite disruption is rated high in such areas. However, risk is mitigated if only a single application is made to an orchard with a stable mite situation. The addition of 1% oil to an Assail spray (the oil itself is miticidal) may help to reduce mite flare-ups in some, but not all, situations. The cumulative effect of multiple neonicotinyl applications for multiple years is unknown, but elevated risk is probable.

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