The phenomenon described is a key concept in plant breeding.
(1) Mutation: A sudden heritable change in the genetic material.
(2) Polyploidy: The condition of having more than two complete sets of chromosomes.
(3) Luxuriance: Refers to vigorous vegetative growth, which may or may not be associated with increased yield or superiority over parents. It's more a descriptive term for strong growth. Sometimes used interchangeably with heterosis in a loose sense for F1 vigor, but heterosis is more specific.
(4) Heterosis (or Hybrid Vigor): This term specifically describes the phenomenon where an F\(_1\) hybrid (the first-generation offspring of a cross between two genetically different parents) exhibits superiority in one or more characters (such as yield, vigor, growth rate, fertility, or stress tolerance) compared to both of its parents. This is the basis for developing and utilizing hybrid varieties in many crops.
Therefore, the superiority of an F\(_1\) hybrid over both its parents is known as heterosis.
Heterosis