Premium
Do elevated ozone and variable light alter carbon transport to roots in sugar maple?
Author(s) -
Topa M. A.,
McDermitt D. J.,
Yun S.C.,
King P. S.
Publication year - 2004
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.1469-8137.2004.01014.x
Subject(s) - maple , shoot , aceraceae , sugar , ozone , fumigation , biomass partitioning , photosynthesis , botany , chemistry , seedling , horticulture , sink (geography) , biomass (ecology) , annual growth cycle of grapevines , biology , agronomy , food science , organic chemistry , cartography , geography
Summary• Here we conducted a series of 14 C pulse‐chase labeling experiments to test the hypothesis that ozone reduces allocation of recently assimilated carbon to roots of sugar maple ( Acer saccharum ). • Sugar maple seedlings were fumigated with 1.0 ×, 1.7 × and 3.0 × ambient ozone in open‐top chambers for 3 yr under low and high light. Shoots were labeled with 14 CO 2 for 1 h in August of year 3, and seedlings were harvested 0, 4, 24 and 48 h after labeling. • Three years of ozone fumigation reduced total biomass of seedlings in low and high light treatments by 49% and 34%, respectively, and reduced per cent allocation of total seedling biomass to roots. Ozone similarly reduced allocation of net 14 C (gross 14 CO 2 assimilated at time = 0 minus respiratory losses) to roots after 48 h, but not gross 14 C, despite significant ozone effects on 14 CO 2 assimilation, leaf‐level partitioning, and retention of gross carbon in shoots. • Although ozone delayed transport of 14 C out of leaves initially, it had no effect on the transport process per se . Any reduction in net allocation to roots is most likely a function of changes in whole‐plant source–sink relationships, with control a function of both shoot and root traits.