Question

Identify the "Orthodox" seeds
(A) Sorghum
(B) Mango
(C) Sapota
(D) Cotton
Choose the correct answer from the options given below

• A. (A) only
• B. (B), (C) and (D) only
• C. (B) and (C) only
• D. (A) and (D) only

Hint:

To remember seed types:
- Orthodox seeds (drying tolerant): Grains, legumes, cotton, most temperate crops.
- Recalcitrant seeds (drying sensitive): Large tropical fruits (Mango, Jackfruit, Avocado), rubber, cocoa, oak.
This distinction is crucial for ex-situ germplasm conservation in seed banks.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Based on their storage behavior and tolerance to dehydration, seeds are classified into two main categories: orthodox and recalcitrant.
Orthodox seeds can survive significant desiccation (drying down to $5-10\%$ moisture content) and storage at sub-zero temperatures without losing viability.
Recalcitrant seeds cannot survive significant drying or low temperatures, losing viability quickly if they are dehydrated or frozen.

Step 2: Detailed Explanation:
Let us analyze the seed storage behavior of the listed plants:
Sorghum (*Sorghum bicolor*) produces dry, starch-rich grains.
These seeds can be dried to low moisture levels and stored at sub-zero temperatures for decades, showing classic orthodox behavior, matching Statement (A).
Cotton (*Gossypium* species) seeds also tolerate significant drying and freezing temperatures, which is typical of orthodox seeds, matching Statement (D).
Mango (*Mangifera indica*) produces large, fleshy seeds.
These seeds are highly sensitive to desiccation; if their moisture content drops below $30\%$, they lose viability quickly and cannot survive sub-zero storage, which is typical of recalcitrant seeds, matching Statement (B).
Sapota (*Manilkara zapota*) is a tropical fruit tree whose seeds are also sensitive to drying and cold storage, behaving as recalcitrant seeds, matching Statement (C).
Therefore, Sorghum (A) and Cotton (D) are orthodox seeds, while Mango (B) and Sapota (C) are recalcitrant seeds.

Step 3: Final Answer:
Sorghum (A) and Cotton (D) are orthodox seeds.
This corresponds to Option (D).