The study results of new economically important causal agents of diseases and fruit pests were presented. Over 20 types of Erwinia amylovora have been isolated and identified on pome fruits. The most frequent peach, apricot, and plum diseases are the following: brown fruit rot, drying of small branches and canker. The importance of virus free planting material and resistant cultivars was emphasized. Using the nested PCR and PCR-RFLP methods showed the presence of Phytophthora fragarie var. rubi on three raspberry cultivars. Cecidial raspberry drying is one of the most economically harmful disease. Bacterial raspberry blight was described for the first time in Serbia. Acarology studies are directed towards the following: mechanisms of plant resistance, resistance of mites towards acaricides, efficacy of biopesticides and development of molecular methods for the faster identification of species. The increase in the population of Lymatria dispar, Cacopsylla pruni and Carcopidae was assessed in orchards.Prikazani su rezultati istraživanja novih bolesti i štetočina voćaka sa posebnim osvrtom na: molekularnu detekciju patogena, Pseudomonas syringae na koštičavom voću, sojeve Erwinia amylovora na jabučastim voćkama, prouzrokovače mrke truleži (Monilinia spp.) i rak rana (Leucostoma spp.) na koštičavim vrstama voćaka, molekularne metode za utvrđivanje prisustva Phytophthora fragariae var. rubi na malini, cecidoizno sušenje maline, prouzrokovača bakteriozne plamenjače maline (Pseudomonas syringae pv. syringae), akarološka istraživanja, kao i na porast brojnosti Lymantria dispar, Cacopsylla pruni i cikada penuša (Cercopidae), zaštitu voćaka u organskoj proizvodnji
