1. a reproductive system in fungi and algae in which sexual reproduction requires the fusion of cells or gametes from two genetically different mating types or strains.
Usage: biology; mycology; technical

Examples

• Heterothallism in fungi ensures genetic diversity by requiring two compatible mating types to reproduce.
• Many mushroom species exhibit heterothallism, preventing self-fertilization.
• The study of heterothallism has revealed how certain organisms maintain genetic variation across generations.
• In heterothallism, the two mating types are often designated as plus and minus strains.
• Researchers use heterothallism to understand reproductive isolation in fungal populations.