Novel Pyrimidine Derivatives as Regulators of Barley Growth and Photosynthesis During the Vegetation Period

A comparative analysis of the regulatory effect of the plant hormone auxin IAA (1H-indol-3-yl) acetic acid and novel synthetic azaheterocyclic compounds, derivatives of sodium and potassium salts of 6-methyl-2-mercapto-4-hydroxypyrimidine (Methyur and Kamethur) and other pyrimidine derivatives, at a concentration of 10-7M, on the growth and photosynthesis ofspring barley (Hordeum vulgare L.) variety Salome during the vegetation period was carried out. Morphological traits such as shoot and root length (mm) and biochemical indicators such as content of chlorophylls a, b and carotenoids (mg/g fresh weight) of 4-week-old barley plants were studied. A screening of the most active synthetic azaheterocyclic compounds, pyrimidine derivatives that demonstrated auxin-like and cytokinin-like activity on the growth and photosynthesis of barley plants was conducted. The correlation between the chemical structure and the species specificity of the regulatory effect of synthetic azaheterocyclic compounds, pyrimidine derivatives, on plant growth and photosynthesis is discussed. A conclusion was made regarding the prospects of using most of the active synthetic azaheterocyclic compounds, pyrimidine derivatives, as new regulators of barley growth and photosynthesis.