z-logo
Premium
Transport of root‐respired CO 2 via the transpiration stream affects aboveground carbon assimilation and CO 2 efflux in trees
Author(s) -
Bloemen Jasper,
McGuire Mary Anne,
Aubrey Doug P.,
Teskey Robert O.,
Steppe Kathy
Publication year - 2013
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/j.1469-8137.2012.04366.x
Subject(s) - transpiration , transpiration stream , xylem , respiration , botany , assimilation (phonology) , carbon dioxide , biology , photosynthesis , autotroph , photorespiration , woody plant , salicaceae , chemistry , ecology , linguistics , philosophy , genetics , bacteria
Summary Upward transport of CO 2 via the transpiration stream from belowground to aboveground tissues occurs in tree stems. Despite potentially important implications for our understanding of plant physiology, the fate of internally transported CO 2 derived from autotrophic respiratory processes remains unclear. We infused a 13 CO 2 ‐labeled aqueous solution into the base of 7‐yr‐old field‐grown eastern cottonwood ( Populus deltoides ) trees to investigate the effect of xylem‐transported CO 2 derived from the root system on aboveground carbon assimilation and CO 2 efflux. The 13 C label was transported internally and detected throughout the tree. Up to 17% of the infused label was assimilated, while the remainder diffused to the atmosphere via stem and branch efflux. The largest amount of assimilated 13 C was found in branch woody tissues, while only a small quantity was assimilated in the foliage. Petioles were more highly enriched in 13 C than other leaf tissues. Our results confirm a recycling pathway for respired CO 2 and indicate that internal transport of CO 2 from the root system may confound the interpretation of efflux‐based estimates of woody tissue respiration and patterns of carbohydrate allocation.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here