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What is the ploidy level of ‘Nugget’, an interspecific hybrid developed in marigold?
EXPLANATION
Breeding Methods, Heterosis & F1 Hybrids in F
- 'Nugget' Marigold:
- pioneering interspecific $F_1$ hybrid bred by crossing diploid African marigold (Tagetes erecta, $2n = 2x = 24$) with tetraploid French marigold (Tagetes patula, $2n = 4x = 48$).
- Ploidy and Cytogenetics:
- Combining gametes of $n = x = 12$ and $n = 2x = 24$ produces a sterile triploid ($2n = 3x = 36$).
- Because triploid plants cannot form viable gametes or set seeds, they do not suffer seed-induced senescence, resulting in continuous, prolific, long-lasting flowering throughout summer.
- Correct Option: Option 3 (Triploid).
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