Question

Match List-I with List-II

List-I (Theory proposed) & List-II (Author)
(A) Contact exchange & (I) Bray
(B) Air capacity of soil & (II) Jenny and Overstreet
(C) Mobility of nutrients & (III) Mitscherlich
(D) Growth factor and yield & (IV) Khonke

• (A) - (II), (B) - (IV), (C) - (I), (D) - (III)
• (A) - (I), (B) - (II), (C) - (III), (D) - (IV)
• (A) - (IV), (B) - (III), (C) - (II), (D) - (I)
• (A) - (III), (B) - (IV), (C) - (I), (D) - (II)

Hint:

Remember the key associations:
- Contact Exchange: Proposed by Jenny and Overstreet.
- Nutrient Mobility: Proposed by Bray (Bray's soil test for phosphorus).
Matching these two provides a quick path to the correct option.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This matching question focuses on key theories and mathematical laws proposed by soil scientists and plant physiologists regarding nutrient uptake, soil physical properties, and crop yields.

Step 3: Detailed Explanation:
Let us match each scientific theory or concept with its correct author:
- (A) Contact exchange $\rightarrow$ Jenny and Overstreet (II): Hans Jenny and Roy Overstreet proposed the "Contact Exchange Theory" of plant nutrient uptake in 1939.
This theory states that ion transfer can occur directly between the root surface and soil clay particles when their oscillating double layers overlap, without the ions dissolving into the soil solution.
- (B) Air capacity of soil $\rightarrow$ Khonke (IV): Helmut Kohnke conducted extensive research on soil physical properties and defined soil air capacity and composition parameters essential for plant root respiration.
- (C) Mobility of nutrients $\rightarrow$ Bray (I): Roger H. Bray proposed the "Nutrient Mobility Concept" in 1954, classifying nutrients as mobile or immobile in the soil, which formed the basis for soil testing and fertilizer recommendation models.
- (D) Growth factor and yield $\rightarrow$ Mitscherlich (III): E.A. Mitscherlich formulated the "Law of Diminishing Increments" (a mathematical yield equation) showing how crop yield responds quantitatively to increasing levels of growth factors or fertilizers.
This matching sequence gives: (A) - (II), (B) - (IV), (C) - (I), (D) - (III).
This matches Option (A).

Step 4: Final Answer:
The correct matching sequence is (A) - (II), (B) - (IV), (C) - (I), (D) - (III).