HORTICULTURE

Detailed explanation-1: -Whittlesey divided the whole world into 13 agricultural regions.

Detailed explanation-2: -Derwent Whittlesey is famous for developing the concept of eleven distinct agricultural regions in the 1930s. Whittlesey divided these eleven regions into some that were important to developed societies (e.g. livestock farming) and some that were important to developing societies (e.g. pastoral nomadism).

Detailed explanation-3: -One such attempt was made by Derwent Whittlesey in 1936. He defined agricultural region as an uninterrupted area having some kind of homogeneity with a specifically defined outer limit (1936).