Provado (imidacloprid) – Provado was the first registered compound of the relatively new class of synthetic analogs of nicotine, neonicotinyls. Provado, and other neonicotinyls, act in the nerve synapse like nicotine acetylcholine. In tree fruits it is generally used as a systemic insecticide and stomach poison. It does have contact insecticidal properties, however the residue is relatively short-lived in the environment. Instead, it is absorbed into leaves, where is can have a long effective residue. Provado is relatively safe for mammals.
Lepidopteran pests
Codling moth – Provado has only low to moderate toxicity to codling
moth in laboratory studies and provided very little suppression of fruit
injury in a field trial.
Leafrollers – We have conducted only one field trial with Provado against pandemis leafroller and it provided very little suppression of larval densities.
Lacanobia fruitworm – We have conducted one test with Provado against Lacanobia and it provided no suppression of the larval population.
Indirect/secondary pests
Provado is primarily used as an aphicide in Washington, but also will provide
adequate suppression of leafminers and white apple leafhopper. Provado
is somewhat toxic to campylomma, but cannot be used during the critical
period for prevention of damage (bloom). There is no apparent direct
effect on mites.
Pear pests
The use of Provado is an important control tactic for control of both pear
psylla and grape mealybug in pear and mealybug in apple. Provado is effective
against the early instars of both of these pests (first and second instars
of pear psylla, ‘soft-shell’, and second and third instars
of grape mealybug, ‘crawlers’). Effectiveness against older
instars of these pests is greatly reduced, and there is relatively little
activity against adults. Using oil as an adjuvant to Provado has been
demonstrated to increase mortality of pear psylla and grape mealybug.
Provado is only registered for post-bloom use in both pear and apple. Thus, in order to use it effectively early in the season for both pear psylla and grape mealybug control, applications should be applied as soon after petal fall as possible (once bees are out of the orchard). This petal fall timing has proven to be particularly effective during growing seasons with relatively mild winters, when bloom comes relatively early. In more ‘normal’ years, an application of Provado at petal fall can be too late to have maximum effectiveness against grape mealybug; observations of ‘crawlers’ should be made before the spray is applied.
The summer generation of grape mealybug, as well as summer generations of pear psylla, can be controlled using Provado as well. However, the effectiveness of the material is reduced relative to the early season applications. Additionally, Provado has a negative effect on the beneficial mirid bug campylomma (an early season pest in apple). Campylomma is an important pear psylla predator.
Beneficial arthropods
Provado, like other neonicotinyls, has been associated with an increase
in mite populations, possibly by hormoligosis. Provado has low toxicity
against predatory mites and the effect of mite flare-ups is not consistent
so the risk is considered low to moderate. Provado is considered moderately
toxic to Colpoclypeus florus, lacewings and coccinellids.