Agriculturist :: Agriculturist (n.) One engaged or skilled in agriculture; a husbandman.
Culturist :: Culturist (n.) One who is an advocate of culture.
Floriculturist :: Floriculturist (n.) One skilled in the cultivation of flowers; a florist.
Sylviculturist :: Sylviculture (n.) The cultivation of forest trees for timber or other purposes; forestry; arboriculture.