Mucor racemosus

Mucor racemosus belongs to the kingdom Fungi, phylum Zygomycota, and genus Mucor. It is a common mold fungus found globally in soils, organic debris, and air. While primarily acting as a saprotroph, it frequently acts as an opportunistic pathogen that leads to significant agricultural losses, particularly during storage and transport.

The fungus is responsible for mucor rot, a type of soft rot affecting a wide range of crops including fruits, vegetables, tubers, and stored seeds. The infection often starts at the site of physical injuries, where the fungus quickly colonizes the nutrient-rich plant tissues, leading to rapid decay.

Its biological cycle is characterized by the production of sporangiospores within sporangia, which are elevated on branched sporophores. These spores are highly resistant and easily dispersed by air currents, water, or contact with contaminated handling equipment. Under harsh conditions, the fungus can form thick-walled zygospores that ensure its survival in soil for long periods.

Environmental conditions such as high humidity (above 80%) and warm temperatures (20–30°C) significantly accelerate the growth and colonization rates of Mucor racemosus. Poorly ventilated storage facilities create an ideal microclimate for the development of the characteristic greyish-white cottony mycelial mats, which eventually soften and rot the host tissues.

The economic impact of Mucor racemosus is significant, particularly in post-harvest settings where it can render entire batches of produce unsalable. Effective management involves integrated strategies:

• Strict sanitation of storage areas and containers.
• Maintaining low temperatures and proper aeration to inhibit fungal development.
• Careful handling during harvest to minimize wounds.
• Application of suitable fungicides for seed treatments.