Identification of deep bark canker agent of walnut and study of its phenotypic, pathogenic, holotypic and genetic diversity in Iran

Abstract

The deep bark canker of the walnut is a serious threat to walnut plants that had an increasing verge since recent years. This disease is caused by Brenneria rubrifaciens bacteria. Therefore, this research was carried out with an aim to identify the deep bark canker agent. The suspected samples having symptoms were collected from the bark and branches of walnut trees. After purification, the phenotypic and biochemical specification of separations was assessed. Even the genetic diversity of pathogen population was conducted with BOX-polymerase chains reaction (PCR) technique and BOXAIR primer. Based on the phenotypic and biochemical specifications, 30 isolates were identified as B. rubrifaciens. In PCR reaction, the specific amplicons of size 537 and 671 bp in the case study strains were amplified via specific primer pairs. The present study is a prime report on outbreak of this disease in Iran and bacterial pathogenicity evidence of B. rubrifaciens on fruit in the world.