Step 1: Understanding the Concept:
Essential plant nutrients play specific physiological roles in plant metabolism.
Deficiencies in these nutrients lead to characteristic visual symptoms and physiological disorders in susceptible crops. Step 2: Detailed Explanation:
Let us match each plant nutrient in List I with its associated physiological role or deficiency symptom in List II:
- A. Manganese (Mn): A deficiency in manganese causes a specific physiological disorder in oats known as II. Grey speck of oats.
This disorder is characterized by greyish-brown spots or specks appearing on the leaves, which can lead to structural collapse of the foliage.
Thus, A matches with II.
- B. Boron (B): Boron is essential for cell wall synthesis, sugar translocation, and reproductive development.
It plays a critical role in pollen germination, pollen tube growth, and subsequent III. Seed setting and fertilization.
A deficiency in boron can lead to poor grain set and barren ears.
Thus, B matches with III.
- C. Molybdenum (Mo): Molybdenum is a key component of the nitrogenase and nitrate reductase enzymes.
A deficiency in molybdenum in cauliflower causes a characteristic symptom called IV. Whiptail of cauliflower, where the leaf blades fail to develop properly, leaving only the central midrib.
Thus, C matches with IV.
- D. Potassium (K): Potassium is the most abundant univalent cation in plant cells.
It acts as the I. Master cation, regulating cellular osmoregulation, stomatal movement, and enzyme activation without becoming part of the plant's structural components.
Thus, D matches with I.
Combining these pairs yields the sequence: A - II, B - III, C - IV, D - I. Step 3: Final Answer:
The correct matching sequence is A – II, B – III, C – IV, D – I.
