TY - JOUR
T1 - Photosynthesis and crop growth of spring oilseed rape and broccoli under elevated tropospheric ozone
AU - De Bock, Maarten
AU - Ceulemans, Reinhart
AU - Horemans, Nele
AU - Guisez, Yves
AU - Vandermeiren, Karine
A2 - Vandenhove, Hildegarde
A2 - Vanmarcke, Hans
N1 - Score = 10
PY - 2012/10
Y1 - 2012/10
N2 - 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 (2007–2009). Brassica napus L.and Brassica oleracea L. 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.
AB - 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 (2007–2009). Brassica napus L.and Brassica oleracea L. 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.
KW - Stress response
KW - Photosynthesis
KW - Brassica Ozone
UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/ezp_126009
UR - http://knowledgecentre.sckcen.be/so2/bibref/9792
U2 - 10.1016/j.envexpbot.2012.03.008
DO - 10.1016/j.envexpbot.2012.03.008
M3 - Article
SN - 0098-8472
VL - 82
SP - 28
EP - 36
JO - Environmental and Experimental Botany
JF - Environmental and Experimental Botany
ER -