Spot the Solution Quiz Quiz

Explore key diseases affecting groundnut crops and understand their identification, transmission, and management strategies. Ideal for students and agricultural enthusiasts seeking to deepen their crop protection knowledge.

1. Identifying Early Leaf Spot in Groundnut

   A farmer notices small brown spots with a yellow halo on the upper surface of groundnut leaves early in the season. Which disease is most likely responsible?

   1. Early leaf spot
   2. Rust
   3. Late leaf spot
   4. Cercospora blight

   Explanation: Early leaf spot, caused by Passalora arachidicola, typically appears as small brown spots with yellow halos early in the groundnut season. Late leaf spot lesions are darker and lack prominent yellow halos. Rust presents as reddish-orange pustules, while Cercospora blight forms irregular spots without halos.

2. Transmission of Groundnut Rosette Virus

   How is groundnut rosette virus primarily spread from plant to plant in an agricultural field?

   1. Irrigation water
   2. Wind
   3. Aphids
   4. Soil nematodes

   Explanation: Aphids, especially Aphis craccivora, are the major vectors of groundnut rosette virus, efficiently transmitting the disease. Wind and irrigation water do not spread the virus, and soil nematodes are not involved in its transmission.

3. Symptoms of Groundnut Rust

   What distinguishing symptom on groundnut leaves would indicate infestation by Puccinia arachidis, the causal agent of rust?

   1. Water-soaked lesions on pods
   2. Reddish-brown pustules on undersides of leaves
   3. White powdery residue on stems
   4. Circular yellow spots with a grey center

   Explanation: Reddish-brown pustules indicate rust infection caused by Puccinia arachidis. Circular yellow spots with grey centers are not typical for rust. Powdery residues suggest powdery mildew, and water-soaked lesions on pods suggest other fungal infections.

4. Management of Collar Rot in Groundnut

   To prevent collar rot in groundnut seedlings, which strategy is most effective?

   1. Spraying insecticides
   2. Seed treatment with fungicides
   3. Using excessive nitrogen fertilizer
   4. Flooding the field

   Explanation: Seed treatment with fungicides effectively prevents collar rot by protecting seedlings during germination. Excessive nitrogen fertilizer can increase susceptibility to disease, flooding promotes fungal growth, and insecticides do not control fungal pathogens.

5. Aspergillus Flavus in Groundnut Storage

   Which factor most increases the risk of aflatoxin contamination by Aspergillus flavus during groundnut storage?

   1. Low humidity and good ventilation
   2. Immediate drying after harvest
   3. High moisture content in stored pods
   4. Storage in sealed, dry containers

   Explanation: High moisture in stored pods allows Aspergillus flavus to thrive, increasing aflatoxin risk. Low humidity and ventilated conditions reduce contamination, immediate drying after harvest prevents fungal growth, and sealed, dry containers help maintain quality.