Etiological study on Oleander knot in Montenegro

Abstract

Olender (Olender nerii L.) is wide spread ornamental plant on the coast in Montenegro. Symptoms of knots appears on leaves and shoots noticed on oleander plants in Herceg Novi and Bečići during 2005-2007.A number of non levan bacterial strains were islolated on nutrinent sucrose agar (SNA), from the knots on olender leaves and shoots. Investigated strains are Gram negative, oxidative and fluorescent on King, s medium B. They ere negative in oxidase, pectinse and arginin dehidrolase test, while induct HR in tobacco after 24 hours of inoculation. Small pale white knots appear on inoculated oleander leaves three weeks after inoculation, and they are very similar to those recorded in natural infection. Investigated strains do not produced a necrosis on artificially pear and lemon fruits as well as on bean pods. Invstigated strains not hydrolised gelatine and esculine and don't utilized lactose, xilose and DL- lactate; they utilize sucrose and sorbitole. According obtained results and their comparing with literature data we concluded that olenaneder knots in Montengro is caused by Pseudomonas savastanoi pv. nerii. It is the first record of these pathogen in Montenegro.

U radu su proučene bakteriološke odlike izolata bakterije izolovane iz tumora formiranih na listovima i mladarima oleandera (Nerium oleander L.). Na osnovu rezultata testova patogenosti, odgajivačkih i biohemijskih karakteristika i njihovim poređenjem sa podacima iz literature zaključeno je da pomenute simptome bolesti na oleanderu prouzrokuje fitopatogena bakterija Pseudomonas savastanoi pv. nerii, ekonomski značajan pathogen ove ukrasne biljke na području Mediterana.