Phoma stem canker

The fungus Plenodomus enteroleucus is a well-known pathogen responsible for phoma stem canker, a devastating disease in agricultural production. It acts as a primary threat to crop health by colonizing vascular tissues and causing systemic dysfunction. The presence of this fungus often leads to significant physiological stress in affected plants, hindering nutrient and water transport.

This disease targets a wide range of plants belonging to the Brassicaceae family. Key crops at risk include oilseed rape (canola), cabbage, mustard, and several other vegetable crops. The pathogen is highly adaptable and can survive in diverse environmental conditions, which facilitates its persistence in agricultural fields year after year.

Initial symptoms include leaf spotting characterized by pale centers with numerous small, dark pycnidia. As the infection progresses, the pathogen spreads to the stem, causing lesions at the base (crown). These stem cankers weaken the structural integrity of the plant, often leading to lodging, stem breaking, and premature senescence, which drastically reduces yield potential.

The development of the disease is favored by high humidity and moderate temperatures, which promote the dispersal of spores from infected plant residues. Rain splash and wind are the primary mechanisms for spore transmission. Infected seeds are also a critical pathway for the introduction of the pathogen into new areas, making initial seed health a crucial factor in disease management.

Integrated pest management is essential for effective control. Key strategies include the use of disease-free, certified seeds, maintaining a strict crop rotation cycle to prevent soil-borne inoculum buildup, and the prompt removal or deep incorporation of crop stubble. Fungicide application during the early growth stages is strongly recommended to protect the crop during vulnerable periods of development.