THE CONTENT OF PHOTOSYNTHETIC PIGMENTS IN THE LEAVES OF HIPPOPHAЁ RHAMNOIDES L. INTRODUCED INTO THE REPUBLIC OF DAGESTAN

The study of flexibility of the photosynthetic apparatus and its ability to adapt to changing external conditions are of great importance while researching plants state. The most informative indicator of the physiological plants state, characterizing resistance under stressful conditions, is the content of chlorophylls and carotenoids and some ratios of pigment concentrations. The aim of the research was to study the quantitative content of chlorophylls a and b, carotenoids and their ratios in the leaves of plants of the genus Hippophaё rhamnoides L. introduced into the conditions of southern Dagestan. The object of study was the leaves of the common sea buckthorn cultivars of Azerbaijani breeding: female specimens of ‘Shafa’, ‘Zafarani’ and the pollinator ‘Toslaran’. The chlorophyll a content in the leaves of the introduced cultivars was 0.79 mg/g (‘Shafa’), 0.73 mg/g (‘Zafarani’) and 0.78 mg/g (‘Toslaran’) of the raw mass. The same indicator for the unsorted sample (control) is 9.1 % lower (0.36 mg/g). The higher chlorophyll b content is shown by the ‘Shafa’ (0.37 mg/g) and ‘Zafarani’ (0.30 mg/g) cultivars, while in the control (unsorted sample) it is two times less (0.15 mg/g). The carotenoid content of ‘Shafa’ (0.22 mg/g), ‘Zafarani’ (0.19 mg/g) and ‘Toslaran’ (0.23 mg/g) cultivars is 1.8 –2 times higher than that of the unsorted sample (0.11 mg/g). The amount of chlorophylls in the leaves of introduced ‘Shafa’, ‘Zafarani’, and ‘Toslaran’ increased by 12 % compared to the unsorted plant (control). The chlorophyll a/b ratio in the introduced leaves ranged from 2.14 (‘Shafa’) to 2.43 (‘Zafarani’). A high chlorophyll/carotenoid ratio was recorded in the ‘Zafarani’ cultivar (5.42), despite a decrease in the amount of chlorophylls in it. The control has the lowest value (4.36). The total amount of pigments in the leaves of the introduced cultivars varies from 1.22 mg/g (‘Zafarani’) to 1.38 mg/g (‘Shafa’) of raw weight. The total amount of photosynthetic pigments in the control (0.62 mg/g) is 10.2 % lower than in the introduced plants. The dynamics of the quantitative content of chlorophylls and carotenoids in the leaves of Hippophaё rhamnoides showed a slight variability in cultivars belonging to the Azerbaijani breeding. The maximum content of chlorophylls and carotenoids, during the period of active growth, is characterized by the ‘Shafa’ cultivar (1.38 mg/g of raw mass). According to the ratio of chlorophyll a/b, sum (a+b)/carotenoids, ‘Zafarani’ cultivar was isolated (2.43–5.42). Thus, the study of the quantitative content of chlorophylls and carotenoids in the leaves of common sea buckthorn allowed us to identify cultivars ‘Shafa’, ‘Zafarani’ and ‘Toslaran’ (pollinator) with a high level of accumulation of photosynthetic pigments. The introduced plants have successfully adapted to the conditions of southern Dagestan.