Common fungal infections plaguing sesame crops

“I lost everything growing sesame. My yield was pitiful, barely covering costs. Sesame farming isn’t for me—it’s not profitable. Diseases and fungi have cursed my fields, destroying my crops.” These are the anguished cries of inexperienced farmers, unaware of the science and skill needed to master sesame cultivation. Like all agriculture, sesame farming isn’t a game of chance or a quick scheme—it’s a craft rooted in understanding plant needs and combating their diseases.

In today’s blog post, we explore  and share practical solutions to help farmers safeguard their yields, protect their profits, and avoid devastating losses.

Common Fungal Diseases in Sesame

Alternaria Leaf Spot

A Small, dark brown to black spots with concentric rings on leaves, often leading to premature leaf drop. Severe infections can affect stems and pods, reducing seed quality.

Impact: Reduced photosynthesis, lower seed yield, and poor oil content.

Cercospora Leaf Spot

Irregular grayish-white spots with dark borders on leaves, which may coalesce, causing large dead areas. Infected leaves may yellow and drop prematurely.

Impact: Decreased leaf area, reduced seed weight, and lower yield.

Powdery Mildew

Symptoms: White to grayish powdery patches on leaves and stems, which may turn yellow or brown over time. Severe cases lead to distorted leaves and stunted growth.

Impact: Reduced photosynthesis and poor seed development.

Fusarium Wilt

Wilting, yellowing, and drooping of leaves, often starting from the lower part of the plant. Vascular tissues may show brown discoloration, and plants may die prematurely.

Impact: Complete plant loss in severe cases, leading to significant yield reduction.

Solutions for Managing Fungal Diseases in Sesame

Effective management of fungal diseases in sesame requires an integrated approach combining cultural, biological, and chemical strategies. Below are practical solutions to prevent and control these diseases:

Cultural Practices

• Crop Rotation: Rotate sesame with non-host crops like cereals or legumes for 2–3 years to break the disease cycle and reduce soil-borne pathogens like Fusarium
• Field Sanitation: Remove and destroy crop residues after harvest to eliminate fungal spores. Avoid planting sesame in fields with a history of fungal diseases.
• Proper Spacing: Use adequate plant spacing to improve air circulation, reducing humidity around plants and minimizing conditions favorable for diseases like powdery mildew.
• Timely Planting: Plant sesame early in the season to avoid peak disease periods, especially for diseases like charcoal rot, which thrive under high temperatures and drought.
• Water Management: Avoid waterlogging and ensure proper drainage, as excessive moisture promotes diseases like Fusarium wilt and charcoal rot.

Chemical Control

Chemical control is a very effective way to control fungi in sesame farm which can be done by either effective seed treatment of the use of fungicide

Fungicides: Apply fungicides like Azoxystrobin, Difenoconazole, carbendazim, mancozeb, or copper-based fungicides for foliar diseases such as Alternaria and Cercospora leaf spots. For powdery mildew, sulfur-based fungicides or triazoles may be effective. Always follow local regulations and recommended application rates.

Seed Treatment: Treat seeds with fungicides like thiram or captan before planting to protect against soil-borne pathogens like Fusarium and Macrophomina.

Timing: Apply fungicides at the first sign of disease or as a preventive measure during high-risk periods (e.g., high humidity or warm temperatures).

For Farmer in Nigeria and many African country can use the following Fungicide for fungi treatment in sesame field.

 5Star by Rainbow

Active ingredient: Azoxystrobin 200g/l + Difenoconazole125g/l

Application rate: 500ml/ha (30-40ml per 20lt Knapsack)

Blue Snow by SARO

Active ingredient: Azoxystrobin 200g/l + Difenoconazole125g/l

Application rate: 500ml/ha (30-40ml per 20lt Knapsack)

 

Monitoring and Early Detection

• Regularly scout fields for early signs of fungal diseases, especially during flowering and pod formation stages when sesame is most vulnerable.
• Use diagnostic tools or consult local agricultural extension services to confirm the presence of specific pathogens and tailor control measures accordingly

Conclusion

Fungal diseases pose a significant challenge to sesame production, but with proactive management, their impact can be minimized. By adopting resistant varieties, practicing good field hygiene, and using targeted chemical control, farmers can protect their sesame crops and ensure healthy yields. Regular monitoring and adapting to local conditions are key to staying ahead of these diseases.

Happy farming, and may your sesame fields thrive!