8th INTERNATIONAL WHEAT CONFERENCE

electrophoretic lectins and lipoxygenase spectra, endogenic SA content ) infected by
Fusarium blight and Alternaria blight agents and SA effect, as well as exogenic lectin at
early stages of ontogeny demonstrate various changes of studied indices regarding resistant
and susceptible wheat lines and cultivars that proves not only the contingency of such
biochemical characteristics with plant resistance but also their involvement in the formation
of protective mechanisms, which increase plant resistance to such phyto-diseases.
There have been detected differential changes in lectins activity and abscisic acid content
under water deficiency, hyperthermia and combined effect of the both stress factors
upon plants regarding different in terms of drought-heat resistance of wheat cultivars
and lines depending on stress factor resistance, which proves that such biologically active
compounds are the essential elements of biochemical protective system and are of great
importance in forming plant drought-heat resistance mechanisms. Apparently, lectin
synthesis is initiated by abscisic acid, the increase whereof precedes lectin accumulation.
There has been drawn a conclusion that the studied biochemical indices really constitute
effective components of wheat protective system and can be used when developing techniques
for the assessment of wheat resistance to Fusarium blight and Alternaria blight,
draught-heat resistance at early breeding stages, as well as that it is possible to use exogenic
salicylic acid and lectins to stimulate protective mechanisms and increase wheat
resistance to phyto-diseases and abiotic stress.
461