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An F1 hybrid (or filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where it may appear as F1 crossbreed. The term is sometimes written with a subscript, as F1 hybrid.
Often the most expensive seed varieties in the catalogues are labelled as F1 hybrids. This article explains what F1 hybrids are and assesses their advantages and disadvantages. We often see F1 hybrid seeds in catalogues and, nearly as often, we wonder what exactly they are.