През август опасността от болестите и вредителите по овощните дървета все още не е отминала

For apple cultivars that are susceptible to powdery mildew, control of this disease also continues. For simultaneous control of scab, it is best to use fungicides that are effective against both pathogens. Cultivars resistant to scab – Prima, COOP-10, Frolina, Liberty, Jonafree, Jonathan, Pioneer, McFree, Pilot, Topaz, Novamak, Sava, Rubinola, etc., are sprayed only against powdery mildew.

In August, treatments are also carried out against bitter pit /spots/ in apple. Damage from this non-infectious disorder is observed during the ripening period and later during storage. The affected fruits are dotted with numerous dark, sunken spots, which are most often concentrated in the lower part of the fruit. Later they become more intensely coloured; in red-coloured fruits they acquire a dark red colour, while in yellow- and green-coloured fruits they become light green to green. Sometimes the affected apples show no external symptoms and do not differ from healthy ones, but when cut, brown pits scattered among the healthy flesh are visible. Bitter pit consists of dark brown spongy tissue with a bitter taste. To prevent this disorder, treatments are carried out two to three times with CaCl₂  - 0.6 %. The first spraying is carried out about one month before harvest, and the subsequent ones at intervals of 10-12 days. The foliar fertilizer Wuxal Calcium – 300-600 ml/da is also recommended. With it, a minimum of 6 sprayings are carried out, the first after fruit set, and the subsequent ones at intervals of 12-15 days. It is necessary to avoid water           stress in the trees, and harvesting should be carried out at the most favourable dates for each cultivar.

During the first half of August, control of the second generation of codling moth continues.

There are still plant protection measures to be taken in pear, cherry, peach and strawberry.

In organic production the use of synthetic pesticides is not permitted. For the control of fungal diseases, copper-containing and sulphur-containing fungicides are used. For control of codling moth and oriental fruit moth, Madex Top and Madex Twin – 10 ml/da are approved, as well as dispensers – RAK 3+4 for codling moth and RAK 5+6 and FEROCON AM for oriental fruit moth. Naturalis OD is included in the list for control of the common pear psylla.

For control of the apple blotch leafminer, the effective bioinsecticide is Neem Azal T/S – 300 ml/da.

Sineis 480SC is authorised for use in: strawberry against thrips; apricot, peach and nectarine against peach twig borer; pear against pear psylla; and apple against codling moth and apple blotch leafminer.

Information on plant protection products that are approved against the various diseases and pests in August can be found in issue 7/2018 of the journal “Plant Protection”.