Question

Passing an angled horizontal blade beneath a nursery bed at a specified depth to cut newly penetrating roots and to loosen and aerate soil.

• A. Side cutting
• B. Undercutting
• C. Root Pruning
• D. Wrenching

Hint:

Undercutting = Sharp blade, Severs roots.
Wrenching = Blunt/Tilted blade, Lifts and Loosens soil.
Both aim to make the seedling "transplant-ready."

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question describes a technical operation in bare-root nursery management used to prepare seedlings for the stress of transplantation.

Step 2: Detailed Explanation:

• Undercutting (B): This is the process of passing a sharp horizontal blade under the nursery bed at a depth of 10-20cm. It severs the taproot. This encourages the plant to produce a dense mass of lateral and fibrous roots higher up. It also checks the height growth, making the seedling more "sturdy."

• Wrenching (D): Often follows undercutting. A thicker, tilted blade is passed through, which lifts the seedlings slightly and then drops them. This breaks smaller roots, creates air gaps, and "shocks" the plant into physiological dormancy, making it tougher for transplanting.

• Root Pruning (C): A general term for any root-cutting activity.
• Side Cutting (A): Cutting the lateral roots between rows.

• Differentiation: While the question mentions "loosening and aerating" (features of wrenching), the primary mechanical act described—"passing a blade... to cut roots"—is the specific definition of Undercutting.

Step 3: Final Answer:
The operation described is Undercutting.