Occurrence of Epitrimerus pyri Nal. (Acarida: Eriophyidae) and the results of control.
Observations in pear orchards in the Belgrade area and 2 areas of the Vojvodina region of Yugoslavia in 1987 showed that deutogyne females of Epitrimerus pyri emerged at commencement of flowering and oviposited at the base of the rosettes, after which the protogyne forms settled on the fruits, where they fed below the calyx. Maximum numbers occurred on the fruits in May-June. Later, these forms followed the growth of the annual shoots, causing defoliation in young orchards. In the case of varieties ripening in August and later, russeting of the fruits occurred. In control tests, the best results, with very good reduction in mite numbers, were obtained with 1.5% DNC [DNOC] followed by 2 applications of 0.2% dicofol, one before and one after flowering. The compounds were applied with an atomizer at a rate of 500 litres/3300 m2. However, russeting still occurred on some varieties.