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Title: Transport rates and concentration gradients during grain filling in wheat

Conference · · Plant Physiol., Suppl.; (United States)
OSTI ID:5004733

Short-term mass transport rates into wheat ears were calculated at mid grain fill from /sup 32/PO/sub 4/ translocation velocities and sieve tube sap concentrations in the peduncle. Over a wide range of velocities (8.5 to 170 cm/hr), sieve tube sap concentrations (514 to 1050 milliosmolal) and grains per ear (20 to 54 in intact ears, as few as 7 in partially degrained ears), there were no evident differences in the rate of mass transport per grain through the peduncle. Increased sieve tube sap concentration was accompanied in the endosperm cavity sap by increased sucrose concentration, but amino acid concentration and total osmolality remained essentially constant. Thus the rate of transport into the grains appeared to remain constant in spite of altered concentration gradients across the crease tissues of the grain and changing sucrose concentration in the endosperm cavity. The constancy of endosperm cavity sap osmolality suggests that osmoregulatory processes in the grain may play a role in regulating transport rate into the grain.

Research Organization:
Washington State Univ., Pullman
OSTI ID:
5004733
Journal Information:
Plant Physiol., Suppl.; (United States), Vol. 80:4; Conference: Annual meeting of the American Society of Plant Physiologists, Baton Rouge, LA, USA, 8-12 Jun 1986
Country of Publication:
United States
Language:
English