Sooty stripe

Sooty stripe is a significant fungal disease affecting sorghum, caused by the pathogen Ramulispora sorghi. This disease primarily affects leaves and is known to reduce grain yield and biomass quality, especially in regions with high humidity and favorable thermal conditions for fungal growth.

The characteristic symptoms include long, narrow lesions along the leaf veins. These lesions start as tan or reddish-brown stripes and eventually become dark or black due to the formation of numerous fungal micro-sclerotia, giving the leaves a "sooty" or dusty appearance during the disease progression.

The development and spread of Ramulispora sorghi are heavily dependent on climatic conditions. Prolonged periods of warm temperatures (between 20°C and 28°C) combined with high rainfall or high relative humidity trigger rapid sporulation, allowing the fungus to infect healthy tissues efficiently via wind and splashing rain.

The impact of sooty stripe on sorghum yield is primarily due to the destruction of photosynthetic tissue. As the leaves prematurely senesce and die, the plant loses the capacity to fill grains properly, resulting in lightweight kernels and reduced overall crop quality, which can be devastating for commercial agricultural production.

Effective disease management strategies involve an integrated approach. Farmers are encouraged to select resistant sorghum hybrids, perform deep plowing to bury crop residues where the pathogen overwinters, and rotate crops to break the disease cycle. In severe cases, the application of targeted fungicides during the early stages of disease development is highly recommended.