Differential root responses in two cultivars of winter wheat (Triticum aestivum L.) to elevated ozone concentration under fully open-air field conditions

Abstract

The effect of elevated tropospheric ozone concentration [O3] on root processes in wheat systems of different O3 sensitivity is not well understood. Two wheat cultivars (cv. Y15 and YN19) with contrasting O3 tolerance were grown in a fully open-air O3 enrichment platform for one season. We found that elevated O3 (EO3) (50% above the ambient O3) significantly decreased the total biomass at all key growth stages and the yield of the O3-sensitive cultivar YN19 but did not affect those of the O3-tolerant cultivar Y15. EO3 significantly decreased the root biomass of two wheat cultivars at the jointing and grain-filling stages. EO3 significantly decreased the root length, length density, surface ar..