Effects of light on respiration and oxygen isotope fractionation in soybean cotyledons

Published

Journal Article

Light effects on electron flow through the cyanide-resistant respiratory pathway, oxygen isotope fractionation and total respiration were studied in soybean (Glycine max L.) cotyledons. During the first 12 h of illumination there was an increase in both electron partitioning through the alternative pathway and oxygen isotope fractionation by the alternative oxidase. The latter probably indicates a change in the properties of the alternative oxidase. There was no engagement of the alternative oxidase in darkness and its fractionation was 27‰. In green cotyledons 60% of the respiration flux was through the alternative pathway and the alternative oxidase fractionation was 32‰. Exposing previously illuminated tissue to continuous darkness induced a decrease in the electron partitioning through the alternative pathway. However, this decrease was not directly linked with the low cellular sugar concentration resulting from the lack of light because 5 min of light every 12 h was sufficient to keep the alternative pathway engaged to the same extent as plants grown under control conditions.

Full Text

Duke Authors

Cited Authors

  • Ribas-Carbo, M; Robinson, SA; Gonzàlez-Meler, MA; Lennon, AM; Giles, L; Siedow, JN; Berry, JA

Published Date

  • September 25, 2000

Published In

Volume / Issue

  • 23 / 9

Start / End Page

  • 983 - 989

International Standard Serial Number (ISSN)

  • 0140-7791

Digital Object Identifier (DOI)

  • 10.1046/j.1365-3040.2000.00607.x

Citation Source

  • Scopus