Natural variation in ozone sensitivity among Arabidopsis thaliana accessions and its relation to stomatal conductance.
Genetic variation between naturally occurring populations provides a unique source to unravel the complex mechanisms of stress tolerance. Here, we have analysed O(3) sensitivity of 93 natural Arabidopsis thaliana accessions together with five O(3)-sensitive mutants to acute O(3) exposure. The variation in O(3) sensitivity among the natural accessions was much higher than among the O(3)-sensitive mutants and corresponding wild types. A subset of nine accessions with major variation in their O(3) responses was studied in more detail. Among the traits assayed, stomatal conductance (g(st)) was an important factor determining O(3) sensitivity of the selected accessions. The most O(3)-sensitive accession, Cvi-0, had constitutively high g(st), leading to high initial O(3) uptake rate and dose received during the first 30 min of exposure. Analyzing O(3)-induced changes in stress hormone concentrations indicated that jasmonate (JA) concentration was also positively correlated with leaf damage. Quantitative trait loci (QTL) mapping in a Col-0 x Cvi-0 recombinant inbred line (RIL) population identified three QTLs for O(3) sensitivity, and one for high water loss of Cvi-0. The major O(3) QTL mapped to the same position as the water loss QTL further supporting the role of stomata in regulating O(3) entry and damage.
Brosché
Mikael
M
Division of Plant Biology, Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland.
Merilo
Ebe
E
Mayer
Florian
F
Pechter
Priit
P
Puzõrjova
Irina
I
Brader
Günter
G
Kangasjärvi
Jaakko
J
Kollist
Hannes
H
D000704:Analysis of Variance; D000975:Antioxidants / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D003681:Dehydration; D014644:Genetic Variation / Q000187:drug effects*; D007178:Inbreeding; D009154:Mutation / Q000235:genetics; D010084:Oxidation-Reduction / Q000187:drug effects; D010126:Ozone / Q000378:metabolism / Q000494:pharmacology*; D010788:Photosynthesis / Q000187:drug effects; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D054046:Plant Stomata / Q000187:drug effects* / Q000502:physiology*; D040641:Quantitative Trait Loci / Q000235:genetics; D011891:Rain; D013696:Temperature; D013997:Time Factors
D000975:Antioxidants; D010937:Plant Growth Regulators; D010126:Ozone