Funny thing is, it wasn't agricultural advances, at least initially. It was chemistry and mechanics. Haber-Bosch process of ammonia synthesis created cheap fertilizer, mechanization dramatically increased productivity. New plant varieties with higher yields came later.
Synthetic fertilizer and mechanization are commonly seen as agricultural advances in the same way that quantum computing is an advance in the field of computer science even though much of the implementation is physics.
Funny thing is, it wasn't agricultural advances, at least initially. It was chemistry and mechanics. Haber-Bosch process of ammonia synthesis created cheap fertilizer, mechanization dramatically increased productivity. New plant varieties with higher yields came later.