Root Fungus Control Challenge Quiz

Explore the key concepts and practical strategies for effectively managing root fungal diseases in mango horticulture. This quiz assesses your understanding of common threats, prevention techniques, and suitable treatments for healthy mango cultivation.

1. Common Pathogens

   Which root fungal pathogen most commonly causes wilt disease in mango orchards, often leading to sudden plant death?

   1. Fusarium oxysporum
   2. Colletotrichum gloeosporioides
   3. Cercospora mangiferae
   4. Powdery mildew

   Explanation: Fusarium oxysporum is a well-known soil-borne fungus responsible for wilt disease in mangoes, causing blockage of water-conducting tissues. Powdery mildew primarily affects leaves and flowers, not roots. Cercospora mangiferae causes leaf spot, while Colletotrichum gloeosporioides is associated mainly with anthracnose on fruits and leaves, not roots.

2. Disease Symptoms Recognition

   A mango tree displays yellowing leaves, stunted growth, and root rot; lab analysis shows fungal hyphae around roots. Which is the most probable reason?

   1. Poor root aeration enabling Phytophthora infection
   2. Graft incompatibility
   3. Nutrient excess only
   4. Excessive pruning stimulating root disease

   Explanation: Poorly drained soils encourage Phytophthora root rot, leading to typical symptoms such as root decay and yellowing leaves. Excessive pruning and graft incompatibility do not directly cause fungal root infections. While nutrient excess can stress plants, it is not the primary cause when fungal pathogens are observed.

3. Cultural Controls

   Which recommended agricultural practice helps prevent root fungal diseases in mango plantations?

   1. Dense planting to shade soil
   2. Ensuring proper soil drainage
   3. Frequent leaf wetting
   4. Applying high-nitrogen fertilizer constantly

   Explanation: Good soil drainage prevents waterlogging, which reduces the risk of fungal pathogens such as Phytophthora. Frequent leaf wetting primarily increases foliar diseases. Dense planting reduces air movement and can favor diseases. Excess high-nitrogen use may stimulate weak growth susceptible to infection.

4. Chemical Management

   When root fungus is confirmed in mango, which category of chemicals is typically used as a control measure?

   1. Insecticides
   2. Soil-applied fungicides
   3. Defoliants
   4. Herbicides

   Explanation: Soil-applied fungicides target soil-borne pathogens at the infection site. Herbicides target unwanted plants, insecticides address insect pests, and defoliants remove leaves, none of which control fungal root infections.

5. Resistant Varieties

   How can using disease-resistant mango rootstocks help control root fungal diseases in a new orchard?

   1. They require higher fungicide application
   2. They increase susceptibility to insect pests
   3. They reduce susceptibility to soil pathogens
   4. They slow fruit ripening

   Explanation: Resistant rootstocks provide genetic defense against soil-borne pathogens, reducing infection rates. They do not increase insect pests, require more fungicide, or affect fruit ripening directly. This strategy is a preventive approach in disease management.