Effect of L-Glutamate on Senescence Induced Proline Accumulation in Excised Rice Leaves Under Dark and Light Regimes

The effect of L-glutamate on the senescence-induced proline accumulation in dark and light was studied in the excised leaves of rice (Orym saliva L. cv. Ratna). During senescence, 53 fold and 7 fold increase in proline content were observed in dark and light respectively in the excised leaves fter 72 hr. Senescence- induced proline accumulation in the L-glutamate treated excised leaves exhibited a decreasing trend with increasing concentrations of L-glutamate (0–50 mM) in dark. But on incubation in light proline content increased slowly in the leaves treated with L-glutamate upto 10 mM followed by a sharp increase at 50 mM. The result suggests that L- glutamate exhibits an opposite effect on senescence- induced proline accumulation in dark and light in the excised rice leaves.