Publication
Title
Photosynthesis and crop growth of spring oilseed rape and broccoli under elevated tropospheric ozone
Author
Abstract
The impact of a season-long exposure to moderately elevated tropospheric O3 concentrations on the canopy growth and photosynthetic capacity of two important Brassica crops, spring oilseed rape and broccoli, was studied during three consecutive growing seasons (20072009). Brassica napus L. cv. Ability and Brassica oleracea L. cv. Monaco were exposed to non-filtered ambient air (NF) and non-filtered air with addition of 20 (NF+) and/or 40 ppb O3 (NF++) in open-top chambers. Light saturated CO2 assimilation (Asat), stomatal conductance (gst), maximum and actual quantum yield of photosystem II (Fv/Fm, Fv′/Fm′), performance index (PI) and leaf area index (LAI) were monitored on a weekly basis from emergence or planting until harvest. Before flowering, elevated O3 did not have an influence on LAI nor on the photosynthetic capacity of the upper canopy leaves of either crops. This corresponded with the absence of a reduction of aboveground biomass of oilseed rape at maximum leaf area (MLA) and of broccoli plants harvested before flowering. After flowering, which coincided with MLA, the oilseed rape canopy showed a faster decline of LAI and of the chlorophyll content in NF+ compared to NF. In the NF++ treatment, this effect was intensified with an additional decrease of Asat, gst, Fv/Fm, Fv′/Fm′ and PI. In broccoli these detrimental O3 effects were only detected in the lower canopy leaves. The changes in canopy development and photosynthetic performance of the upper canopy leaves can unravel the underlying mechanisms leading to the contrasting yield effects of O3 on broccoli and spring oilseed rape that were previously reported (De Bock et al., 2011).
Language
English
Source (journal)
Environmental and experimental botany. - Oxford, 1976, currens
Publication
Oxford : 2012
ISSN
0098-8472
Volume/pages
82(2012), p. 28-36
ISI
000305767400004
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 04.06.2012
Last edited 08.07.2017
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