Rhizoctonia solani is a soilborne fungus that can attack all parts of the peanut plant. Unlike Sclerotium rolfsii which causes Southern stem rot, the mold growth of Rhizoctonia solani is rarely visible to the naked eye. As the lesions expand, stems may become girdled, which causes wilt and collapse of an entire limb.
Pegs develop similar symptoms of decay that result in shedding of pods from vines during harvest.