Potential of mycorrhizal fungi (Piriformospora indica) as a biological control of clubroot disease on canola

Colonization of roots of 6-d-old canola seedlings by Piriformospora indica Verma: (A) non-treated control and (B) roots with characteristic chlamydospore of P. indica. Photo credit: Sedaghatkish et al.

Piriformospora indica is a very unusual fungal species, because it can live and reproduce inside the roots of canola (Brassica napus), where it forms a beneficial relationship that is reported to reduce stress and increase crop growth. It has also been proposed as a potential biological control agent against clubroot, caused by Plasmodiophora brassicae.

Read this paper in the Canadian Journal of Plant Science

Clubroot is an important disease of canola and the management of clubroot is a challenge worldwide. Growth cabinet and field trials were conducted to assess the efficacy of P. indica against clubroot. In the growth room studies, canola seed was coated with spores of P. indica and planted, together with non-treated seed (controls), in soil inoculated with selected concentrations of pathogen spores.

In the field trials, treated seed and controls were planted in naturally infested soil at a site in southern Ontario. Each study was replicated and repeated. Microscopic observation confirmed that canola roots grown from treated seed under controlled conditions were colonized by P. indica. However, P. indica did not consistently reduce clubroot severity and did not promote the growth of canola under the study conditions.

Read the paper — Seed treatment of canola (Brassica napus) with the endomycorrhizal fungus Piriformospora indica does not reduce clubroot by Afsaneh Sedaghatkish, Bruce D. Gossen, and Mary Ruth McDonald.