Determination of bacterial canker resistance level in Iranian sour cherry germplasm

Bacterial canker disease caused by Pseudomons syringae pv. syringae, is one of the most damaging diseases in sour cherries. In this study, relative resistance of some local sour cherries to this disease was evaluated. Totally, 46 genotypes in adult stage in two repetitive years (2018 and 2019) and 18 genotypes in seedling stage at year 2020 were examined. A mixture of three local P. s. pv. syringae isolates was used as inoculum. Saplings trunks were inoculated in autumn 2019 and canker length was measured one year later. Adult trees were inoculated in autumn 2017 and canker length was recorded one and two years later. Based on result, mean canker length was different among genotypes in both stages. In saplings, the most and the least canker length were rated for genotypes 230 and 125, respectively. Compound analysis of adult trees data showed the least and the most canker lengths were related to genotypes 208 and 104, respectively which were thus rated as the most susceptible and the most resistant genotypes. Based on the results obtained from adult plants, planting of susceptible genotypes like 108, 206 and 220 in risk area is not recommended.