Question

In the Indian sub-continent, two most wide spread genetic groups of Bemisia tabaci are

• A. Asia I and Asia II2
• B. Asia II1 and Asia II3
• C. Asia I and Asia II3
• D. Asia I and Asia III

Hint:

Remember that Bemisia tabaci in India is dominated by the Asia I and Asia II 3 genetic groups, which are key vectors for destructive crop viruses.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
The sweetpotato whitefly, Bemisia tabaci, is not a single uniform species but rather a complex of morphologically identical but genetically distinct cryptic species (or genetic groups).
Identifying the distribution of these genetic groups is vital for managing viral disease transmission.

Step 2: Detailed Explanation:
The Bemisia tabaci species complex is classified globally into several distinct genetic groups based on mitochondrial cytochrome oxidase I (mtCOI) gene sequencing.
In the Indian sub-continent, extensive molecular characterization studies have revealed that the whitefly population is highly diverse.
Among the various genetic groups identified, Asia I and Asia II 3 are the two most dominant, widespread, and ecologically successful genetic groups.
These groups differ significantly in their host range, insecticide resistance levels, and efficiency in transmitting viral pathogens like Begomoviruses (e.g., Tomato Yellow Leaf Curl Virus and Cotton Leaf Curl Virus).
Thus, "Asia I" and "Asia II 3" represent the primary genetic complexes across India and neighboring regions.

Step 3: Final Answer:
Therefore, the correct option is Asia I and Asia II3.