I have a degree in agriculture, but never had to take a specific history of agriculture or had any reading that specifically addressed the subject. I don't quite have a certain era of time I am looking for, I'm just looking for interesting books on how agriculture developed throughout history, different styles of different peoples, how it affected cultures through time, etc.
It's been sitting unread on my bookshelf for some three years now (I just counted) but Slicher van Bath's The Agrarian History of Western Europe 500-1850 did come highly recommended to me as a classic of the field.