Tingey, D.T., K.D. Rodecap, E. H. Lee, W.E. Hogsett and J.W. Gregg. 2002. Pod development increases the ozone sensitivity of Phaseolus vulgaris. Water, Air, and Soil Pollution 139:325-341.
The objective of this study was to determine if the O3 sensitivity of Phaseolus vulgaris L. changed with plant development. Plants exposed to charcoal-filtered air or elevated O3 throughout the study were compared to those exposed only during the vegetative or reproductive stages. Effects of pod development on O3 sensitivity were also examined by removing flowers from a subset of plants. We found that plant developmental stage significantly altered O3 sensitivity. Exposures during vegetative stages caused little foliar injury and had only a small impact on total growth and yield. In contrast, exposures during pod development had a much greater effect on foliar injury, growth and yield. Pod development significantly increased O3 induced foliar injury and O3 impacts on plant growth. We suggest that the greater O3 sensitivity during pod filling and maturation is the consequence of reduced energy levels available for homeostatic repair processes.