Drought-Induced Oxidative Stress in Grassland Plants
Farfan-Vignolo, E.R. and Asard, H. 2012. Effect of elevated CO2 and temperature on the oxidative stress response to drought in Lolium perenne L. and Medicago sativa L. Plant Physiology and Biochemistry 59: 55-62.
"Not surprisingly, in Farfan-Vignolo and Asard's words, "drought caused significant increases in oxidative damage, i.e., in protein oxidation and lipid peroxidation levels." But they found that "in both species the impact of drought on protein oxidation was reduced in future climate conditions [ECO2 and ET]." And speaking of the stress-reducing effect of ECO2, they say that "this 'CO2-protection effect' is reported for a variety of abiotic stress conditions and species," citing the studies of Schwanz and Polle (1998), Sgherri et al. (2000), Geissler et al. (2009), Perez-Lopez et al. (2009), Vurro et al. (2009) and Salazar-Parra et al. (2012), after which they indicate that they "find support for this effect at the level of oxidative cell damage and protein oxidation in water-deficit responses of L. perenne and M. lupulina." And, of course, they also found that even under drought stress, "elevated CO2 significantly affected shoot production in L. perenne (increase by 27-32%)," and that "also in M. lupulina a biomass increase was observed (26-38%)."
Atmospheric CO2 enrichment typically increases the quantity of grassland production, even when plants are stressed for water, while at the same time it additionally enhances the quality of what is produced, as it reduces drought-induced oxidative cell damage and protein oxidation.
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