Question

'Hidden hunger' in plants means

• A. Visual deficiency symptoms only when the nutrient is deficient
• B. Severe yield reduction may occur without appearance of deficiency symptoms
• C. The nutrient is not actually deficient but apparently seems to be deficient
• D. Visual deficiency symptoms of a element are suppressed by other elements

Hint:

Think of "Hidden Hunger" as the "Sub-clinical" stage of a disease.
The plant is not "sick" enough to show spots, but it is too "hungry" to produce a full harvest.
Always trust soil/tissue tests over visual appearance!

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question asks for the definition of "hidden hunger," a specific nutritional state in plants where nutrient concentration is low but not low enough to show visible signs.
Detailed Explanation:

• The Concept of Hidden Hunger:
Hidden hunger occurs when a plant's internal concentration of a nutrient falls below the "critical level" required for maximum growth, but remains above the "threshold" for showing visible symptoms like chlorosis or necrosis.
In this zone, the plant is "hungry" but doesn't "show" it.

• Yield Impact:
Even though the plant looks healthy and green, its metabolic processes are compromised.
This results in a significant reduction in the final yield (biomass or grain) because the nutrient limitation restricts physiological efficiency.
By the time visible symptoms appear, the plant has already suffered permanent and severe damage to its yield potential.

• Diagnosis:
Hidden hunger cannot be detected by visual inspection of the field.
It requires leaf tissue analysis or sap testing to determine the actual nutrient concentration compared to established standards.
Soil testing is also a preventative tool to identify potential hidden hunger before the crop is sown.

• Economic Significance:
It is a "silent thief" for farmers. Many farmers do not apply fertilizers because the crop "looks good," unaware that they are losing $10-20\%$ of their potential income due to suboptimal nutrient levels.

Step 2: Final Answer:
Hidden hunger refers to the state where yield is reduced due to nutrient deficiency despite the absence of any visible deficiency symptoms.