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 pote ntial of 0 and - 0.30 MPa were cultured, for 6 h at 20-degrees-C suppl ying uniformly labelled [C-14]sugars like sucrose, glucose and fructos e through cotyledons under normal and water deficit conditions. Uptake of exogenously supplied sugars by cotyledons and their transport to e mbryonic axis was faster in chickpea cv C-214, a relatively water defi cit tolerant cultivar than PBG-1 which is relatively sensitive to wate r deficit. Uptake of exogenously supplied [C-14]sugars in stressed see dlings of both the cultivars as compared to their non-stressed control s was less. An increased export of [C-14] towards the epicotyl in comp arison with hypocotyl of stress tolerant cultivar C-214 was observed u nder conditions of water stress. The higher percent retention of label in cotyledons of stressed seedlings of cv C-214 than non-stressed con trols indicated decreased export of sucrose to embryonic axis under co nditions of water stress. The conversion of glucose to sucrose in coty ledons of stressed seedlings was slowed down.