Rhizoctonia bataticola

Rhizoctonia bataticola, frequently classified as Macrophomina phaseolina, is a significant soilborne fungal pathogen. As a member of the fungal kingdom, it acts as a necrotrophic parasite, causing charcoal rot in a wide range of host plants, leading to severe economic losses in agriculture globally.

The pathogen attacks a broad spectrum of crops, including major commodities such as soybean, sunflower, corn, sorghum, and cotton. The fungus typically infects the root system and the lower stem, colonizing the plant's vascular tissue and effectively cutting off the transportation of water and essential minerals.

The life cycle is characterized by the production of microsclerotia, which serve as the primary survival structures in soil and crop debris for several years. When environmental conditions are favorable, these sclerotia germinate and infect susceptible roots. The fungus then produces enzymes that degrade plant cell walls, leading to rapid tissue decay.

Environmental conditions are critical for disease development. The fungus thrives in hot and dry climates, specifically when soil temperatures reach between 28°C and 35°C. High temperature and moisture stress combined make the host plants significantly more susceptible to successful colonization by the pathogen.

The economic impact of this pathogen includes stunted growth, premature senescence, and yield losses of up to 50% in heavily infested fields. Control measures emphasize integrated management: rotating with non-host crops, maintaining soil fertility to reduce plant stress, managing irrigation to avoid drought periods, and using registered fungicides for seed treatment.

• Selection of resistant or tolerant crop varieties.
• Deep tillage to bury infected plant residues.
• Balanced fertilization to improve crop vigor.