Genetic background of commercial sugarcane Modern commercial sugarcane cultivars are heterozygous and typically derive germplasm from how many <i>Saccharum</i> species?

Introduction / Context:
Commercial sugarcane is a complex interspecific hybrid, primarily between S. officinarum and S. spontaneum, with contributions from other species such as S. robustum, S. barberi, and S. sinense. This broad germplasm base increases heterozygosity and agronomic resilience.

Given Data / Assumptions:

• Breeding history includes repeated backcrossing and selection.
• Multiple Saccharum species contribute traits like sucrose content and stress tolerance.
• The range sought reflects typical, not extreme, contributions.

Concept / Approach:
Summarize the commonly cited composition of modern cultivars: two major parents plus minor inputs from additional related species, totaling around 3–5 species in practical breeding lineages.

Step-by-Step Solution:

Verification / Alternative check:
Breeding literature and cultivar pedigrees often list these species as sources of key traits.

Why Other Options Are Wrong:

• 1–3 underestimates genetic inputs beyond the two primaries.
• 5–7 or more overstates routine contributions for commercial lines.

Common Pitfalls:
Assuming all cultivars share identical ancestry; ranges vary, but 3–5 species is a solid generalization.

Final Answer:
3–5 Saccharum species