Leaf and spathe spot of calla lily caused by an undescribed species of Plectosphaerella

摘要

Unknown spot diseases were observed on calla lily leaves and spathes in Japan. Fungi isolated from spots were identified as Plectosphaerella sp. based on morphological characteristics. Inoculation and reisolation confirmed the pathogenicity of the fungi on calla lily. The fungi were distinct from known species of Plectosphaerella in terms of rDNA nucleotide sequences, growth rate, and specific pathogenicity on Zantedeschia species. This report is the first in the world literature of a spot disease of calla lily caused by Plectosphaerella sp. Management of this pathogen is important for calla lily cultivation because it degrades spathes having high commercial value.