White Leaves Mystery in Bengal Gram Quiz

Explore key causes, symptoms, and management of white leaf disorders affecting Bengal gram crops. This quiz tests your understanding of crop health and diagnosis in agricultural settings.

  1. Identifying White Patch Symptoms

    A Bengal gram field shows leaves developing irregular white patches while veins remain green. Which disorder is most likely responsible for these symptoms?

    1. Powdery mildew
    2. Zinc deficiency
    3. Root-knot nematode infestation
    4. Fusarium wilt

    Explanation: Zinc deficiency typically causes irregular white or pale patches between veins, with veins staying green. Powdery mildew shows white powdery growth rather than internal discoloration. Fusarium wilt causes wilting, not this type of leaf discoloration. Root-knot nematodes primarily affect roots, leading to galls and stunting, not interveinal white patches.

  2. Early Stage Indicators

    Which early symptom distinguishes zinc deficiency from powdery mildew in Bengal gram plants?

    1. Interveinal white patches with green veins
    2. Yellowing and stunted growth of whole plant
    3. White powdery coating on the upper surface
    4. Complete drying of leaf margins

    Explanation: Interveinal white patches with green veins are characteristic of zinc deficiency in Bengal gram. Powdery mildew forms a white powdery fungal growth, not just color change. Yellowing and complete margin drying are more general or late-stage symptoms of other problems.

  3. Corrective Measures

    Which management practice is most effective for correcting white leaf symptoms due to zinc deficiency in Bengal gram?

    1. Foliar spray of zinc sulfate solution
    2. Crop rotation with cereals
    3. Application of sulphur dust
    4. Use of systemic fungicides

    Explanation: Applying a foliar spray of zinc sulfate supplies the needed micronutrient directly. Sulphur dust is for fungal diseases like powdery mildew. Systemic fungicides control pathogens, not deficiencies. Crop rotation may prevent some diseases but does not directly address zinc deficiency.

  4. Environmental Triggers

    Low availability of zinc in Bengal gram fields is most often associated with which soil condition?

    1. Waterlogged clay soils
    2. Highly alkaline pH
    3. Low organic matter
    4. Extremely acidic pH

    Explanation: Zinc becomes less available in highly alkaline soils, increasing deficiency risk. Waterlogged and acidic soils can cause other nutrient problems. Low organic matter may contribute but is less directly linked to zinc deficiency than high pH.

  5. Yield Impact

    If untreated, how can zinc deficiency affecting white leaves alter Bengal gram crop outcomes?

    1. Reduces flowering and pod set, lowering yields
    2. Leads only to leaf curling with no yield effect
    3. Promotes lodging by weakening stems
    4. Increases root rot incidence significantly

    Explanation: Zinc deficiency slows plant metabolism and growth, reducing flower and pod set, thus lowering yields. Leaf curling alone is not the main result, and zinc deficiency does not directly cause lodging or root rot, though poor growth can make plants more susceptible to stress.