The effect of management and competition on the uptake of 32phosporus by ryegrass, meadow fescue and their natural hybrid.
Single plants of ryegrass, meadow fescue and a triploid hybrid between them were grown in small plots alone or in competition under simulated grazing and hay managements. The extent of the root systems was assessed by injecting 32P to depths of 10, 30 or 60 cm and estimating the activity recovered at three harvests. Root penetration was faster under the "hay" management. Ryegrass and meadow fescue developed roots at 60 cm more slowly when associated with the hybrid, than they did when alone or with one another. The success of the hybrid in competition was apparently increased by its ability to exploit water and nutrients from the deeper regions of the soil.