Late leaf spot
Cercospora personata
Causal Agent:
- Fungal Pathogen: Cercospora personata is a fungal pathogen that causes Cercospora leaf spot, primarily affecting various leguminous crops.
2. Host Range:
- Leguminous Crops: The pathogen commonly infects leguminous plants, including soybeans (Glycine max), peas (Pisum sativum), and other related species.
3. Symptoms:
- Leaf Lesions: Initial symptoms manifest as small, angular lesions on the leaves.
- Lesion Color: Lesions progress to tan or light brown, often with a reddish-purple border.
- Coalescence: Lesions may coalesce, leading to extensive blighting of the foliage.
4. Disease Cycle:
- Survival: The fungus can survive in infected crop residues, acting as a source of inoculum for subsequent infections.
- Infection: Infection occurs through spores (conidia) produced on infected plant material or within pycnidia (fruiting bodies).
- Spread: Conidia are dispersed by wind, rain, or physical contact, initiating new infections on healthy plants.
- Favorable Conditions: Warm and humid conditions promote disease development.
5. Identification:
- Angular Leaf Spots: Identification involves recognizing the angular lesions with a characteristic tan to light brown color.
- Purple Border: The reddish-purple border around the lesions is a distinguishing feature.
- Microscopic Examination: Microscopic examination may reveal the presence of conidia and pycnidia.
6. Management:
- Resistant Varieties: Planting crop varieties with some level of resistance to Cercospora personata is an effective strategy.
- Crop Rotation: Avoiding consecutive cultivation of leguminous crops in the same field can help reduce the pathogen's survival.
- Fungicide Applications: Fungicides may be applied preventively or curatively, especially during periods of high disease pressure.
- Sanitation: Proper removal and destruction of infected crop residues can reduce the source of inoculum.
7. Importance:
- Economic Impact: Cercospora leaf spot caused by Cercospora personata can result in reduced yields and affect the quality of leguminous crops.
- Global Distribution: The pathogen is found in regions where susceptible crops are cultivated.



































