Jute corynespora leaf spot

The causative agent of this plant disease is the fungus Corynespora corchorum. As a pathogenic organism, it targets specific physiological structures of the jute plant, disrupting nutrient uptake and normal plant growth, which ultimately affects the development of the fibrous tissues essential for commercial use.

The primary host for this fungus is the jute plant (Corchorus spp.). While it primarily infects leaves, severe infections can also affect stems, especially under poor ventilation conditions. The disease significantly reduces the yield and quality of the fiber extracted from the stems, making it a serious concern for growers.

The symptoms of the infection include the formation of small, brown, irregular spots on the leaf blades. As the infection progresses, these spots may enlarge and merge, developing concentric rings. Affected leaves often wither and drop prematurely, leading to defoliation which stunts the growth of the entire plant.

Warm and humid environments are the most favorable for the proliferation of Corynespora corchorum. High humidity combined with temperatures between 22°C and 28°C accelerates the production of spores and their spread via wind and rain splashes across the field, leading to rapid disease transmission.

To effectively manage the disease, integrated pest management (IPM) strategies are recommended. These include:

• Crop rotation with non-host plants
• Use of resistant or tolerant jute cultivars
• Deep plowing to bury infested debris
• Timely application of appropriate chemical fungicides