What is a variety, breed and strain? Can these groups be called independent species of organisms?

A variety (from the Latin. Sortis – variety) is a group of agricultural plants of the same species created as a result of breeding (for example, an apple tree) that possess inherited economically valuable traits.
Breed – a group of farm animals of the same species created as a result of breeding (for example, domestic sheep), possessing inherited economically valuable traits. Strain (from it, stamm – basis, tribe) – a pure culture of microorganisms isolated from a specific source or obtained as a result of mutations . No, because they still have similarities with the organisms of their species, only improved.

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