Rye sown in the fall and plowed into the soil in early spring leaves a residue that is highly effective at controlling broad-leaved weeds, but unfortunately for only about 45 days  No major agricultural crop matures from seed in as little as 45 days  Synthetic herbicides, on the other hand, although not any longer-lasting, can be reapplied as the crop grows
Clearly, ttherefore, for major agricultural crops, plowing rye into the soil can play no part in effective weed control
allow for the possibility that plants other than rye, handled the same way, might have the same effect