Compendium of Turfgrass Diseases

Cannabis (Cannabis sativa L., marijuana) plants with symptoms of crown rot, root decay, wilting and plant death were sampled during 2018 and 2019 from seven production greenhouses. Affected tissues...

Several Pythium species cause crown and root rot on cannabis (Cannabis sativa L., marijuana) plants grown under commercial greenhouse conditions

Turfgrasses have been widely used in many residential areas and sport fields for many years. Pythium species can cause severe losses on cereals and other crops as well as ornamental plants such as turfgrass. To study the role of Pythium species in causing seed and root rot and damping-off, plant and soil samples were collected from different regions of Tehran province. Isolates were identified on the basis of morphological characters and cardinal temperature. Pathogenicity of the recovered species was determined on common cool season turfgrasses (Loliumperenne, Poaparatensis and Festucaarundinaceae). Of the 48 recovered Pythium isolates, three species were identified include 66.7% P. aphanidermatum, 18.7% P. catenulatum and 14.6% P. okanoganense. Comparative pathogenicity of Pythium species (total diseases) on turfgrasses showed that P.aphanidermatum was the most aggressive species and P. catenulatum and P. okanoganens were in second and third levels respectively.

Elizabeth E. Jones

Papers

Identification of Pythium species and their pathogenicity on cool season turfgrass in Tehran province