Studies of the Growth in Culture of Excised Wheat Roots

Aeration of root culture medium with air containing 5 % or 10 % CO2 enhances growth, particularly lateral initiation and growth, compared with aeration wilh air or CO2‐free air. This beneficial effect of enhanced CO2 pressure on the growth of cultured roots of Atson Elite 56 wheat ean also be demonstrated in presence of a high (40 %) and inhibiting level of oxygen. 14C labelling from a carbonate–bicarbonate solution of pH 7.0 by cultured wheat roots is enhanced by light and this labelling is not inhibited by the presence of 1 % ethyl urethane.