LEAVES AREA AND PHOTOSYNTHETIC PIGMENTS OF DOMINANT PLANTS OF RURAL PASTURES IN THE STEPPE BELT OF Mount Aragats IN ARMENIA
The article summarizes the scientific results on the assimilation surface and the content of photosynthetic pigments in the leaves of plants in the main meadow groups of the southwestern slope of Mount Aragats (1300-1900 m above sea level). Under the strong influence of environmental and anthropogenic factors these territories are characterized by low productivity, therefore, they need efficient improvement. Within the framework of this scientific article, the task was set to create a database of experimental data on biological parameters responsible for the yield farming. The objects of the current research were the following types of cereals - Goatgrass (Aegilops cylindrica) , Cheat grass (Bromus tectorium) , Bluegrass (Poa bulbosa) , Wheatgrass (Agropyron repens) , Barley (Hordeum bulbosum) , legumes - Sainfoins (Onobrychis radiata) , Clover (Trifolium pratenium) , Cow vetch (Vicia variabilis) , Alfalfa (Medicago sativa) , and herbs - Leafy spurge (Euphorbia virgata) , Tansy (Tanacetum vulgare) , Scabiosa (Scabiosa bipinnata) , Catnip (Nepeta Mussini) , Yarrow (Achillea milleteminium) , Wormwood (Artemisia absinthium). The leaf area was determined by the gravimetric method, pigment extraction was carried out using dimethyl sulfoxide, and their content was measured on an SF-16 spectrophotometer. A wide range of fluctuations in the leaf area in individual species was revealed (0.9-11.5), while the difference between meadow groups was insignificant (4.0-5.9 dm<sup>2</sup>/plant). The amount of pigments in the leaves of herbs was 22% less than that in cereals and legumes, and the ratio of chlorophylls A and B varied within 1.8-3.5. Thus, on the studied foraging grounds, the maximum leaf area was found in perennial cereals, the sum of pigments and chlorophyll A - in legumes, and chlorophyll B - in herbs.