RELATIONSHIP BETWEEN ENDOGENOUS ETHYLENE AND CO2 ASSIMILATION RATE UNDER CONDITIONS OF WATER-STRESS

Relationships between endogenous ethylene and internal carbon dioxide concentration, stomatal resistance and CO2 assimilation rate were inve stigated. The changes of stomatal resistance, amount of released ethyl ene and CO2 assimilation rate in winter wheat ear treated by water str ess and abscisic acid (ABA) application were shown. The results show t hat both water stress and ABA application influenced all of investigat ed parameters. The decrease of amount of released ethylene, significan t depression of CO2 assimilation, increased stomatal resistance and in ternal CO2 concentration after treatments were determined. It was conf irmed that endogenous ethylene is related to CO2 assimilation rate and stomatal resistance what was supported by inhibition of ethylene acti vity by silver thiosulphate.