Bisifusarium blight

Bisifusarium blight is a fungal disease affecting various agricultural crops, caused by species within the Bisifusarium genus. Previously categorized under the broader Fusarium group, these pathogens have been taxonomically reclassified due to their distinct biological and genetic characteristics. This fungus is a soil-borne pathogen that persists in agricultural fields by surviving on infected plant debris and within the soil profile for several seasons.

The host range of Bisifusarium includes major cereal crops such as wheat, barley, and maize. The pathogen typically attacks the root system and the lower stem tissues, although in severe cases, it can systemically colonize the plant. Seedlings are particularly susceptible, often suffering from damping-off or poor establishment, while adult plants may experience stunted growth and premature senescence due to the impairment of water and nutrient transport.

Visible symptoms often begin at the crown of the plant, where reddish-brown or dark lesions appear on the stem base. As the infection progresses, the foliage becomes chlorotic, wilts, and eventually dies. Under humid conditions, a characteristic mycelial growth may be visible at the base of the plant. A diagnostic feature is the necrosis of the root cortex, which significantly weakens the plant's structural integrity and ability to absorb essential minerals.

Development and dissemination of the disease are highly influenced by environmental conditions. High soil moisture, moderate temperatures, and poor field drainage are primary catalysts for fungal proliferation. Additionally, factors that stress the crop, such as nutrient deficiencies, improper soil pH, or competition from weeds, exacerbate the severity of the infection by making the plants more vulnerable to successful colonization by the fungus.

The economic impact of Bisifusarium blight is significant, manifesting in reduced grain yield and lower seed quality. Furthermore, the potential production of mycotoxins by these fungi poses a major risk to food and feed safety standards. Management strategies must be integrated, focusing on

• the use of certified, fungicide-treated seeds;
• implementing diverse crop rotation systems to break the pathogen's life cycle;
• maintaining optimal soil fertility and drainage;
• plowing under crop residues to reduce the initial inoculum load.