EFFECT OF POLYETHYLENE GLYCOL-INDUCED WATER-STRESS ON UPTAKE, INTERCONVERSION AND TRANSPORT OF SUGARS IN CHICKPEA SEEDLINGS

Chickpea seedlings germinated for three days under external water potential of 0 and - 0.30 MPa were cultured, for 6 h at 20-degrees-C supplying uniformly labelled [C-14]sugars like sucrose, glucose and fructose through cotyledons under normal and water deficit conditions. Uptake of exogenously supplied sugars by cotyledons and their transport to embryonic axis was faster in chickpea cv C-214, a relatively water deficit tolerant cultivar than PBG-1 which is relatively sensitive to water deficit. Uptake of exogenously supplied [C-14]sugars in stressed seedlings of both the cultivars as compared to their non-stressed controls was less. An increased export of [C-14] towards the epicotyl in comparison with hypocotyl of stress tolerant cultivar C-214 was observed under conditions of water stress. The higher percent retention of label in cotyledons of stressed seedlings of cv C-214 than non-stressed controls indicated decreased export of sucrose to embryonic axis under conditions of water stress. The conversion of glucose to sucrose in cotyledons of stressed seedlings was slowed down.