[Campbell Biology P.558] In certain cultivated rice strains, the first-generation F1 hybrids... | Practice Question

In certain cultivated rice strains, the first-generation F1 hybrids are vigorous and fertile, but when these F1 hybrids mate, their second-generation F2 offspring are small and sterile. This phenomenon is an example of which reproductive barrier?

  • A: Reduced Hybrid Viability
  • B: Gametic Isolation
  • C: Reduced Hybrid Fertility
  • D: Hybrid Breakdown

Explanation

Hybrid Breakdown occurs when first-generation hybrids are viable and fertile, but subsequent generations F2 become feeble or sterile. This perfectly matches the description of the cultivated rice strains.