Potato anthracnose

Potato anthracnose is a fungal disease caused by Colletotrichum coccodes, which affects the roots, stems, and tubers of the plant. This pathogen is known to cause premature senescence of potato foliage, leading to a significant reduction in tuber yield and poor storage quality, making it a major concern for commercial potato producers.

The fungus is a soil-borne pathogen that thrives on decaying organic matter and can infect a wide range of host plants within the Solanaceae family. Because the pathogen produces durable structures called microsclerotia, it can survive in the soil for several years without a host, making long-term crop rotation essential for managing the disease pressure in fields.

Symptoms of the disease initially appear as small, dark, water-soaked lesions on the lower stems near the soil surface. As the infection progresses, these lesions expand, often causing the stem to collapse. Tubers are typically infected through lenticels or wounds, resulting in greyish-brown spots covered with tiny black, pin-head-sized microsclerotia of the fungus.

Environmental conditions play a crucial role in disease development, with warm and moist weather being particularly favorable for the spread of Colletotrichum coccodes. Plants subjected to environmental stress, such as drought, nutrient deficiencies—especially potassium—and soil compaction, are significantly more susceptible to severe anthracnose outbreaks during the growth cycle.

Integrated management of potato anthracnose focuses on preventing primary infections and reducing soil inoculum levels. This includes planting disease-free seed tubers, implementing extended crop rotations, and ensuring adequate irrigation to avoid drought stress. Chemical control through seed treatment and timely application of foliar fungicides can also mitigate the spread of the pathogen.

• Strict weed management to remove alternative hosts.
• Deep plowing to incorporate plant debris.
• Use of high-quality certified seed potatoes.
• Nutrient management to ensure strong plant growth.