Diseases and pests on Bulgarian oil-bearing rose (Rosa kazanlika VT = Rosadamascena Mill. var. kazanlika)

Oil bearing rose is the most important and essential oil crop in Bulgaria. During the period 1993-1996, on the experimental field of the Research Inst itute for Roses, Aromatic and Medicinal Plants in Kazanlik, Bulgaria, and i n the adjacent rose plantations, we conducted regular observation at 10 day intervals in order to clarify pests and diseases appearance, development, density, distribution and damages on roses. It was found that of diseases, the most severe damages on roses were caused by rust (Phragmidium mucronatu m Pers.) and black spot (Diplocarpon rosae Wolf.). Of the rose attacking pe sts, the cane borer (Agrilus cuprescens Men.), rose curculio (Homalorynchit es hungaricus Fussly.), rose scale insect (Rodoccocus bulgariensis Wunn.), rose chafer (Epicometis hirta Poda.) and Phylloperta horticola proved to be the most destructive. A tendency towards a gradual increasing of the popul ation density in pests of no economic significance has also been recorded.