Acquired changes in stomatal characteristics in response to ozone during plant growth and leaf development of bush beans ( Phaseolus vulgaris L.) indicate phenotypic plasticity

• Published in: Environmental pollution (1987) 2006-04, Vol.140 (3), p.395-405
• Main Authors: Elagöz, Vahram, Han, Susan S., Manning, William J.
• Format: Article
• Language: English
• Subjects: Air Pollutants - toxicity; air pollution; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Bush bean; Climate; cultivars; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on plants and fungi; Environmental Exposure - adverse effects; Fundamental and applied biological sciences. Psychology; genetic variation; Germination - drug effects; Germination - physiology; green beans; Leaf development; lines; Oxidants, Photochemical - toxicity; Ozone; Ozone - toxicity; Phaseolus - drug effects; Phaseolus - growth & development; Phaseolus vulgaris; Phenotype; Phenotypic plasticity; plant growth; Plant Leaves - drug effects; Plant Leaves - growth & development; Plant Transpiration - drug effects; Plant Transpiration - physiology; Seeds - drug effects; Seeds - growth & development; stomata; Stomatal characteristics; stress tolerance; Temperature
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2005.08.024

Bush bean ( Phaseolus vulgaris L.) lines ‘ S156’ (O 3-sensitive)/‘ R123’ (O 3-tolerant) and cultivars ‘ BBL 290’ (O 3-sensitive)/‘ BBL 274’ (O 3-tolerant) were used to study the effects of O 3 on stomatal conductance ( g s), density, and aperture size on leaf and pod surfaces with the objective of establishing links between the degree of plant sensitivity to O 3 and plasticity of stomatal properties in response to O 3. Studies in open-top chambers (OTCs) and in continuously stirred tank reactors (CSTRs) established a clear relationship between plant developmental stages, degrees of O 3 sensitivity and g s: while ‘ S156’ had higher g s rates than ‘ R123’ earlier in development, similar differences between ‘ BBL 290’ and ‘ BBL 274’ were observed at later stages. G s rates on the abaxial leaf surfaces of ‘ S156’ and ‘ BBL 290’, accompanied by low leaf temperatures, were significantly higher than their O 3-tolerant counterparts. Exposure to O 3 in CSTRs had greater and more consistent impacts on both stomatal densities and aperture sizes of O 3-sensitive cultivars. Stomatal densities were highest on the abaxial leaf surfaces of ‘ S156’ and ‘ BBL 290’ at higher O 3 concentrations (60 ppb), but the largest aperture sizes were recorded on the adaxial leaf surfaces at moderate O 3 concentrations (30 ppb). Exposure to O 3 eliminated aperture size differences on the adaxial leaf surfaces between sensitive and tolerant cultivars. Regardless of sensitivity to O 3 and treatment regimes, the smallest aperture sizes and highest stomatal densities were found on the abaxial leaf surface. Our studies showed that O 3 has the potential to affect stomatal plasticity and confirmed the presence of different control mechanisms for stomatal development on each leaf surface. This appeared to be more evident in O 3-sensitive cultivars. O 3 has the potential to affect stomatal development and the presence of different control mechanisms on each leaf surface is confirmed.