introduction: macrophomina phaseolina is the causal agent of soybean charcoal rot. this disease is one of the most prevalent and destructive of soybean in the north of iran. this pathogen has broad host range and invades more than 500 plant species of 75 families, such as caprifoliaceae. symptoms on stems appear as silver-gray lesions near the base, which eventually decay the stem. plants show ...