Chemicals that are used for control of mites on apple and pear are not systemic. Higher volume spray applications to give good cover are needed to get the best results.
- A programme of sprays of sulphur (various products) at reduced rates (3-5 kg a.i. / ha), applied to control mildew on apple, will suppress rust mite and fruit tree red spider mite.
- However, multiple sprays of sulphur are likely to be harmful to the orchard predatory mite, so such an approach is not ideal.
- Some apple varieties are sulphur shy (consult the label for details) but are often safe at low rates.
- Clofentezine (Apollo) and tebufenpyrad (Shirudo) are approved for control of fruit tree red spider mite on apple and are not specifically recommended for control of apple rust mite.
- When applied for control of fruit tree red spider mite, they may give partial control of rust mite but should not be relied on to control damaging infestations.
- The acaricides acequinocyl (Kanemite) and hexythiazox (Nissorun) are recommended for the control of fruit tree red spider mite.
- Trials conducted by the manufacturer of these products showed erratic results against rust mite. As they have a contact mode of action only, they must contact the mites to be effective. They might offer incidental control of rust mite when applied for fruit tree red spider mite control. Hexythiazox (Nissorun) works only on the eggs and early motile stages of fruit tree red spider mite and is ineffective against the adults, so application timing is critical.
- A full approval for spirotetramat (Batavia) on apples for the control of sucking insect pests will help to suppress apple rust mite. It must be applied after flowering and works best when pests are moving from brown wood to green tissue. It will prevent population build-up but does not offer pest ‘knockdown’.
- The bioinsecticide fatty acids (Flipper) has an EAMU approval for use on apples (3419/19). It is effective at controlling sucking insect pests such as aphids, whitefly and mites, so is likely to offer incidental control of apple rust mite when applied for other pests. It is known to complement the use of Batavia as it provides quick ‘knockdown’. Its safety to beneficial insects such as Typhlodromus pyri and the parasitic wasp Platygaster demades is unknown, but it is generally safe to many other predators and parasitoids, so is considered to be more suitable to IPDM programmes than the synthetic pyrethroids.