The Influence of Carbohydrate Status and Low Temperature on the Respiratory Metabolism of Mitochondria from Etiolated Leaves of Winter Wheat

Abstract

The separate and combined effect of sucrose (12%, 7 days) and low temperature (2 °С, 7 days) on the growth of plants, the content of carbohydrates in the leaves and oxidative activity of mitochondria isolated from them has been studied on the etiolated plants of winter wheat (Triticum aestivum L.). It has been shown that sucrose and low temperature cause inhibition of the growth and increasing of the carbohydrates content. Using the different oxidation substrates (malate, malate + rotenone, succinate, NADH and NADPH) have been identified changes in the mitochondrial oxidative activity and the functioning of alternative oxidase and rotenone-insensitive NAD(P)H dehydrogenases. It has been determined that activity of the alternative oxidase and “external” rotenone-insensitive NAD(P)H dehydrogenases in the mitochondria of etiolated leaves depends on the carbohydrate status of the plant, regardless of the growth temperature.

Keywords

• alternative oxidase
• carbohydrates
• low temperature
• rotenone-insensitive NAD(P)H dehydrogenases
• winter wheat