A similar question has been asked before, but I'm sure you can find slightly more in your own research, and it would be mosr specific to your assingment.

First off, you may want to focus on the (debated) idea of agrarian modernization the NSDAP preaches, that could narrow your answer a little

I'm assuming that your academic institution has access to JSTOR, so I'm going to give you some links for your research.

First off, a rather short (only 6 or 7 pages) work by T. Swann Harding of Oxford university during wartime, which gives an overview of a few different states', but focuses mainly on the UK (but Germany is covered): "Food, Agriculture, and the War"

A slightly longer (appr. 20 pages) looking at, once again, the output and allocation of agricultural resources, by Mark Harrison: Resource Mobilization for World War II: The U.S.A., U.K., U.S.S.R., and Germany, 1938-1945

This is less on what happened to the farmers, but why they affiliated with a revolutionary party such as the NSDAP. It does cover the idea of modernization I mentioned earlier, as well as the balance between pro-peasant and politically viable options for the NSDAP. I would suggest reading it all, but the most important bits for you start at 681-682 Kim R. Holmes's "The Forsaken Past: Agrarian Conservatism and National Socialism in Germany"

Dieter Gessner's work details agricultural policy making in interwar Germany, it does cover the "Green Front" (agrarian policies) You're going to want to start at about p769, that's when the NSDAP begins to throw its hat into the ring. Agrarian Protectionism in the Weimar Republic

Your best bets are Gessner and Harding here, but Harding doesnt offer a lot. Good luck!