Importance and climatic distribution of pathogenic fungi associated with bean root and crown in Lorestan Province

Common bean root rot which is a fungal disease is an economically important diseases of the crop product worldwide. Distribution and relative dominance of the disease was investigated in the farms of the major bean cultivating regions and clima of Lorestan province including Azna, Aligudarz, Selseleh, Doroud and Borujerd. Totally, 1164 isolates were obtained using general and selective culture. Pathogenicity of isolates evaluated and confirmed on Akhtar cultivar. The dominant pathogenic fungi were identified based on colony morphology and microscopic characteristics, and then confirmed by molecular technique using β-tubulin and TEF1- αgenes. Frequency of fungal isolate and the pathogenicity tests showed that F. solani, with 33.42 % isolation frequency was the most important causal agent of common bean root and crown rot in Lorestan province, and followed by F. oxysporum, Macrophomina phaseolina and Rhizoctonia solani with 26.55, 15.55 and 7.73 %, respectively. Frequency of roor rot pathogens distributed across bean farms of Selseleh, Borujerd, Azna, , Doroud and Aligudarz were 24.57, 18.64, 16.58, 15.20 and 8.25 %. respectively. The frequency of the pathogen isolated from common bean plants at the early growth, flowering and podding stages was 20.70, 26.37 and 52.92 %, respectively. Based on Climate zoning, the highest frequency of fungal agents was evaluated in semi-humid temperate clima.