Question

Which one of the following species is NOT tetraploid?

• A. Triticum dicoccum
• B. Triticum persicum
• C. Triticum spelta
• D. Triticum timopheevi

Hint:

Hexaploid wheats ($2n=6x=42$, AABBDD): T. aestivum, T. spelta, T. compactum; Tetraploid wheats ($2n=4x=28$, AABB): T. durum, T. dicoccum.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Wheat species in the genus Triticum form a classical polyploid series based on basic chromosome number $x = 7$: diploids ($2n = 2x = 14$), tetraploids ($2n = 4x = 28$), and hexaploids ($2n = 6x = 42$).

Step 2: Detailed Explanation:
Evaluating the ploidy levels:
1. Triticum dicoccum (Emmer wheat): Tetraploid ($2n = 4x = 28$, genome AABB).
2. Triticum persicum (Persian wheat): Tetraploid ($2n = 4x = 28$, genome AABB).
3. Triticum timopheevi: Tetraploid ($2n = 4x = 28$, genome AAGG).
4. Triticum spelta (Spelt wheat): Hexaploid ($2n = 6x = 42$, genome AABBDD).

Step 3: Final Answer:
Therefore, Triticum spelta is NOT tetraploid (it is hexaploid).