PHYTOHORMONE-LIKE EFFECT OF PYRIMIDINE DERIVATIVES ON THE VEGETATIVE GROWTH OF HARICOT BEAN (PHASEOLUS VULGARIS L.)

The phytohormone-like effect of synthetic compounds based on pyrimidine derivatives on the vegetative growth of haricot bean (Phaseolus vulgaris L.) was studied. For this purpose, haricot bean plants were grown from seeds treated with synthetic compounds at a concentration of 10^-6M during the vegetative stage. The effect of synthetic compounds on the growth of haricot bean plants was compared with the effect of phytohormone auxin IAA (1H-indol-3-yl)acetic acid) used in a similar concentration of 10^-6M. The control haricot bean plants were grown from seeds treated with distilled water. The morphometric parameters (average length of shoots and roots (mm), average number of roots (pcs)), and biochemical indicators (content of photosynthetic pigments (µg/ml) - chlorophylls a and b, as well as carotenoids) of haricot bean plants were determined. The effect of synthetic compounds based on pyrimidine derivatives on the vegetative growth of haricot bean was similar to the effect of auxin IAA. The morphometric parameters of 2-week-old haricot bean plants treated with synthetic compounds based on pyrimidine derivatives exceeded similar parameters of control plants: average length of shoots – by 16.98 – 105.66 %, average length of roots – by 105,88 – 288.24 %, average number of roots – by 31.82 – 284.09 %, respectively. The morphometric parameters of 2-week-old haricot bean plants treated with auxin IAA exceeded similar parameters of control plants: average length of shoots - by 86.79 %, average length of roots – by 182.35 %, average number of roots – by 161.36 %, respectively. The cytokinin-like effect of synthetic compounds based on pyrimidine derivatives on the biosynthesis of photosynthetic pigments in the leaves of 2-week-old haricot bean plants was also studied. The content of photosynthetic pigments (µg/ml) in the leaves of 2-week-old haricot bean plants treated with synthetic compounds based on pyrimidine derivatives exceeded similar parameters of control plants: chlorophyll a - by 14.25 – 121.07 %, chlorophyll b - by 3.38 – 145.11 %, chlorophyll a+b - by 15.47 – 85.34 %, carotenoids - by 5.53 – 165.88 %, respectively. The content of photosynthetic pigments (µg/ml) in the leaves of 2-week-old haricot bean plants treated with auxin IAA exceeded similar parameters of control plants: chlorophyll a - by 34.65 %, chlorophyll a+b - by 22.9 %, carotenoids - by 50.98 %, respectively. The plant growth-regulating effect of synthetic compounds based on pyrimidine derivatives depended on their chemical structure. The selected most biologically active synthetic compounds based on pyrimidine derivatives are proposed to be used as new plant growth regulators of haricot bean (P. vulgaris L.).