The mechanism of stomatal closing by salicylic acid inCommelina communis L.
- 611 Downloads
The mechanism of stomatal closing by salicylic acid (SA) has been investigated. The addition of 1 mM SA to fully opened stomata resulted in a significant reduction of 75% in stomatal aperture. Stomata in the treatment of SA with EGTA closed as observed in the treatment of SA. However, the addition of catalase with SA completely inhibited stomatal closing. Stomatal closing induced by SA was also reduced by Ca2+. To understand the relation bewteen stomatal closing by SA and catalase activity, the effect of SA on catalse activity and the effect of AT (catalase inhibitor) on stomatal closing was investigated. SA inhibited 32% of catalase activity. Stomata in isolated epidermis floated on an incubation solution containing 0.1 mM AT closed from 9.6 μm to 3.2 μm after 1 hour. SA stimulated K+ efflux as much as the twice of the control in isolated strips. SA inhibited 53% of photosynthetic activity at the light intensity of 1000 μmole m2 s1 on SA infiltrated leaves. A similar result was found on stomatal conductance in SA infiltrated leaves. These results indicate that SA inhibit catalase activity and increase the concentration of H2O2 in guard cell cytoplasm. H2O2 oxidize the plasma membrane and increase the membrane permeability of K+. The mass efflux of K+ induce the loss of turgor pressure and lead to stomatal closing. The inhibition of photosynthetic activity by SA suggests that stomatal closing by SA is also related with the decrease of photosynthetic activity.
KeywordsCa2+ catalase photosynthesis stomata salicylic acid
Unable to display preview. Download preview PDF.
- Bhatia, D.S., V. Jindal and C.P. Malke. 1986. Effect of salicylic acid and tannic acid on stomatal aperture and some enzyme changes in isolated epidermal peelings ofEuphorbia hirta L.,Biochem. Physiol. Pflanzen.181: 262–264.Google Scholar
- Larque-Saavedra, A. 1979. Stomatal closure in response to acctvlsalicylic acid treatment.Z. Pflazenphysiol. Bd.93: 371–375.Google Scholar
- Lee, J.S. 1995. Effects of salicylic acid and its analogues on stomatal closing inCommelina communis L.J. Korean Envir. Sci. Soc.4: 317–321.Google Scholar
- Lee, J.S. and B.O. Jun. 1997. The mechanism of stomatal closing by H2O2 in epidermal strips ofCommelina communis L.J. Korean Envir. Sci. Soc.6: 125–131.Google Scholar
- Lee, J.S. and B.W. Kim. 1997. Stomatal response by Ozone.Korean J. Ecol.20(2): 83–94.Google Scholar
- Malamy, J. and D.F. Klessig. 1992. Salicylic acid and plant disease resistance.Plant J.2: 643–654.Google Scholar
- Morison, J.I.L. 1987. Intercellular CO2 concentration and stomatal response to CO2.In Stomatal Function. E. Zeigcr. G.D. Farquhar and I.R. Cowan (eds.). Stanford University Press. Stanford, pp. 229–251.Google Scholar