Untersuchungen zum Atmungsstoffwechsel, ATP-Gehalt and Kornzuwachs bei Winterweizen: Investigations of Metabolism of Respiration, ATP Content and Grain Growth of Winter Wheat

Abstract

In the grain filling period the dynamic of dry weight and total nitrogen increment of winter wheat grains was closely paralleled that of ATP level, mitochondria) respiration, succinate dehydrogenase activity and dark respiration. ATP content of grains was lower by about 12 % in the plants analyzed after 5 h light than in the plants analyzed after 15 h darkness. Anaerobic conditions in dark for 15 h decreased the ATP pool by more than 50 %. Darkness for 4 d didn't affect the protein synthesis, but the dry matter production was lower after darkness for more than 2 d due to limited energy and sucrose supply. 2,4-Dinitrophenol inhibited both accumulation of dry matter and of protein. It is concluded that the energy production by the dark respiration is more limiting than the supply of assimilates by the source organs under field conditions.