Genotypic characteristics of Xanthomonas arbaricola pv. juglandis, causal agent of walnut  bacterial blight, based on Rep-PCR in Kohgiluye and Buyer- ahmad province

Mousavi Pour, S. H.; Najafi Pour, G.

doi:10.22055/ppr.2018.13693

Genotypic characteristics of Xanthomonas arbaricola pv. juglandis, causal agent of walnut bacterial blight, based on Rep-PCR in Kohgiluye and Buyer- ahmad province

Document Type : Research paper-Persian

Authors

S. H. Mousavi Pour ¹

G. Najafi Pour ²

¹ Former B.Sc. student, Department of Plant Protection, Jahrom branch, Islamic Azad University

² Assistant Professor of Plant Pathology, Department of Plant Protection, Jahrom branch, Islamic Azad University

10.22055/ppr.2018.13693

Abstract

Background and objective
Walnut bacterial blight, caused by Xanthomonas arboricola pv. juglandis (Xaj) is one of the most important diseases, causing severe damage at the presence of moisture and the optimal temperature for the development of the disease. The aim of this study was walnut bacterial blight detection, in Kohgiluye and Boyer- Ahmad province and evaluation of genetic diversity of Xaj strains using rep-PCR.
Materials and methods
During 2011-1012, several samples of walnut′s leaf and fruit, showed bacterial blight symptoms, were collected from Kohgiluyeh and Boyer- Ahmad province of Iran. Bacterial isolates were studied with bacteriological standard methods. Moreover, genetic fingerprint of Xaj strains were evaluated and phylogenetic tree of them was drawn.
Results
Twenty five isolates of Xaj were showed small, relatively prominent with yellow colony. All isolates were oxidative, Gram and oxidase negative but catalase positive. They hydrolyzed starch and able to produce H₂S from cystein and formed yellow colonies on YDC medium.
Discussion
On the basis of biochemical, phenotypical and virulence test, presence of Xaj in Kohgiluyeh and Boyer- Ahmad province, was revealed. This is the first report of walnut bacterial blight disease in Kohgiluyeh and Boyer-Ahmad province. Genotypic characterization of isolates also was assayed with rep-PCR. All isolates were similar at 73% similarity level, but any relationship among clusters and geographic area were not observed.

Keywords

Xaj

walnut bacterial blight

rep-PCR. genotypic variation