Question

After hatching, the hatching of whitefly passes through:

• A. 2 nymphal instars
• B. 3 nymphal instars
• C. 4 nymphal instars
• D. 5 nymphal instars

Hint:

The crawler stage is the only mobile immature stage - once settled, whiteflies remain stationary until adulthood.

Answer 1

The Correct Option is A

Whitefly life cycle:
Egg → Crawler (1st instar) → Settled nymph (2nd instar) → Pupa → Adult
Only two true nymphal stages (instars)
Total development time: 15
40 days depending on temperature

Answer 2

Life-stage counting method:
After the egg hatches, the whitefly first-instar crawler is mobile and searches for a feeding site; once settled, it moults into a sessile second instar that remains fixed on the leaf. Following this second nymphal stage, the insect enters a non-feeding pupal stage before emerging as a winged adult. Because the pupal stage is morphologically and functionally distinct from a feeding, growing nymph, it is not counted as a further nymphal instar. Counting only the genuinely feeding nymphal stages after hatching therefore gives two nymphal instars before pupation.
Hence, the correct answer is 2 nymphal instars.