Mitigation mechanism of ozone-induced reduction in net photosynthesis of Bangladeshi wheat under soil salinity stress

Abstract

To clarify the combined effects of O3 and soil salinity on net photosynthetic rate, stomatal conductance, and radical scavenging system of Bangladeshi spring wheat cv. BAW1059, plants were grown in two soil salinity levels (irrigated with 0 and 150 mM NaCl solutions) and exposed to three O3 concentrations [charcoal-filtered air (CF), 1.0-fold the ambient O3 concentration (1.0×O3), and 1.5-fold the ambient O3 concentration (1.5×O3)]. The soil salinity mitigated adverse effects of O3 on net photosynthesis in the 7 th and flag leaves. The soil salinity did not induce stomatal closure, indicating no limitation of stomatal O3 uptake. The activities of ascorbate peroxidase and catalase were stimulated by the soil salinity in the 7 th and flag leaves, especially under 1.5×O3 concentration. In the flag leaf, the soil salinity induced a significant increase in dehydroascorbate reductase activity and ascorbate concentration. These results suggest that the soil salinity activated detoxification capacity related to mitigation of O3 damage on net photosynthesis in both 7 th and flag leaves, while the activated enzymes and antioxidants were different between the leaves.

Regulation of ROS Metabolism in Plants under Environmental Stress: A Review of Recent Experimental Evidence

“…The authors concluded that O 3 tolerance improved at different growth stages via regulating antioxidant activities in tolerant cultivars. In another study, O 3 exposure-induced ROS production was scavenged via regulation of antioxidant activities in wheat leaves [ 298 ].…”

Soil physicochemical (colloidal) properties affected by ozonated water and organic fertilization

“…Increasing soil CaCO 3 by the experimental treatments can be due to the enhanced colloidal properties of the soil such as the availably of SOC and nutrients and the improved structure of the soil such as the stability of aggregates. Increasing ozone concentration increased CaCO 3 , which can be due to a more favorite soil medium by affecting soil physical, chemical, and biological properties [ 21 , 31 ].…”