outcrossing; outbreeding
Technical term in genetics and breeding, referring to mating between unrelated individuals of the same species to increase genetic diversity.
Outcrossing is carried out to increase genetic diversity.
This variety was improved through outbreeding.
交配 is a broader term for mating or crossbreeding, while 外交配 specifically refers to outcrossing.
Compound of 外 (outside) + 交配 (mating, crossbreeding). The term is a direct calque from English 'outcrossing' or 'outbreeding'.