BIOCHEMICAL AND PHYSIOLOGICAL MECHANISMS INVOLVED IN PLANT DEFENSE

Rezumat

Plants, being autotrophic organisms fixed in the soil, cannot move to avoid stress factors. However, they have developed during evolution a series of effective means of defense, both against biotic factors and abiotic (drought, radiation, extreme temperatures).
Plants of the species Alnus glutinosa and Fraxinus excelsior were studied to observe how the hydrogen peroxide content changes under the influence of thermal stress (high temperatures). An increase in peroxide content was found at high temperatures, a greater difference compared to the control observed in Fraxinus excelsior, which is better adapted to high temperatures. The salicylic acid content determined in the species Salix alba and Filipendula ulmaria varied depending on the age of the plants and climatic conditions, being higher in young plants and organs and under conditions of thermal and water stress.