Diseases of crops II - SS2 Agriculture Past Questions and Answers - page 2

Coffee leaves affected by Coffee Leaf Rust exhibit yellow-orange, rust-like lesions. These lesions typically appear as powdery masses on the underside of the leaves. Over time, the infected leaves become weak and may fall prematurely. Severe infections can lead to defoliation, negatively impacting the coffee plant's ability to photosynthesize and produce coffee cherries.

Cassava Mosaic Virus is a major concern for food security in certain regions because cassava is a staple crop for millions of people in tropical areas. When infected with this virus, cassava plants exhibit mosaic-like patterns on their leaves and may become stunted, resulting in reduced root yields. Since cassava is a crucial source of carbohydrates in many diets, reduced cassava yields can lead to food shortages, malnutrition, and economic losses for farmers and communities relying on this crop.

Farmers can take several measures to prevent and manage Cocoa Blackpod:

Pruning infected pods and branches to remove the source of the disease.

Maintaining proper spacing between cocoa trees to improve air circulation.

Applying fungicides at the right time to protect pods from fungal infection.

Implementing good agricultural practices, including proper sanitation and hygiene.

Using cocoa varieties that are resistant to Cocoa Blackpod.

Monitoring weather conditions, as the disease thrives in hot and humid environments.

Bacterial Blight can have a significant economic impact on tuber crop farming. It leads to the development of dark, water-soaked lesions on tubers, making them unmarketable. This results in reduced crop yields and financial losses for farmers. Additionally, infected tubers can serve as a source of the pathogen for future crops, perpetuating the problem. The economic impact extends to increased production costs due to the need for disease management strategies, such as the use of antibiotics or copper-based sprays.

Common agricultural practices to control the spread of plant diseases include:

• Crop rotation to break disease cycles and reduce pathogen buildup in the soil.
• Use of disease-resistant crop varieties when available.
• Proper sanitation, including the removal and destruction of infected plant material.
• Monitoring and early detection of diseases to implement timely control measures.
• Application of fungicides or bactericides as needed, following recommended guidelines.
• Maintenance of optimal planting densities and spacing to improve airflow and reduce disease spread.
• Implementation of integrated pest management (IPM) strategies to minimize disease pressure while considering environmental and economic factors.