Differential Effects of X-Irradiation on the Growth and Water Uptake in Bean Seedlings

X-irradiation of one-week-old bean (Phaseolus vulgaris) seedlinp with 2 and 5 kR was found to inhibit subsequent growth and water uptake, the latter more than the former. While in the primary leaves of controls, with passage of time, there was a reduction in both growth and water uptake, radiation increased their growth despite reduction in water uptake. The increase in growth is attributed to possible interference by radiation in the translocation of photoassimilate from the primary leaves to the other parts.