Present Status of Erwinia amylovora in the Republic of North Macedonia

This study aims to give an overview of the status of Erwinia amylovora, isolated from pear (Pyrus communis), wild pear (Pyrus pyraster), apple (Malus silvestris), and quince trees (Cydonia oblonga) from different localities in the Republic of North Macedonia, for the period 2015-2019. Classical biochemical analyses coupled to modern molecular diagnostic tools such as PCR and Real Time PCR were used for the determination of bacteria. Symptomatic fruit trees were no-ticed in almost all investigated localities in Republic of North Macedonia. The most expressed symptoms were recorded during the intensive growth of the shoots. Isolated strains elicited HR in tobacco, necrosis of pear seedlings, and immature pear fruits. Strains possess typical biochemical characteristics com-pared with the positive control, such as non-fluorescent, anaerobic (oxidase negative), levan production, and catalase enzymatic activity, doesn’t hydrolyze gelatine, aesculin, and starch, produce acid from sucrose, fructose, and galac-tose, etc. Amplification of the total bacterial DNA originating from apple, pear, wild pear, and quince trees using PCR followed by agarose electrophoresis, showed that PCR patterns for all investigated native strains are identical to the European reference strain (LMG 1883). TaqMan qPCR was used to quantify E. amylovora DNA from different host plants and locations, during the investigated period. The results indicate that the disease incidence is sporadic and crop dam-ages are of medium economic significance. E. amylovora in the Republic of North Macedonia was identified as a causal agent of fire blight on pear, wild pear, apple, and quince trees in young and old fruit orchards