Agricultural technological boostings are both a bit of a cliché, and underestimated.
Bit of a cliché because stuff as "horse collar" and "heavy plough" keeps appearing as some of magical tools without much contextualisation (we know it was a thing during Antiquity, or that horse harness situation was far less radically different before horse collar, for exemple); but underestimated because large or more diverse agricultural production is for agrarian-based societies a good part of societal development : Appearance of terroirs, for exemple, as regions with specialized production) with more diverse crop set; or necessity of production structuration (large production ask for means to transform it in numbers).
A large boost would have been earlier introduction of fertilizers or lime (in order to embetter poor terrain where only poor crops could be used) while it would have been dependent of either a good stroke of luck for earlier, simpler widespread use.
Sowing would have been some major breaktrough : an ancient/medieval seed drill in Europe would have been really important changes. The waste of seed could approach 1/3 if not 1/2 with broadcast sowing; the productive change would have been huge.