Khardikova S.V., Verkhoshentseva Y.P., Pokhlebina D.S.
PECULIARITIES OF WATER METABOLISM OF ORNAMENTAL SPECIES OF THE GENUS MALUS MILL. IN THE ENVIRONMENTAL CONDITIONS OF THE ORENBURG REGION ^{[№ 5 ' 2017]}
In the steppe zone of the Orenburg region, Apple is one of the first places the plant is fully adapted to local conditions. But, despite this, the growth and development of its in the region yet, limited hydrothermal environmental factor. Therefore, peculiarities of water regime and drought tolerance of ornamental plants, including Apple trees, are important indicators for their use in gardening settlements. The object of this study was 5 ornamental species of the genus Malus Mill.: Siebold Apple tree (Malus sieboldii (Regel) Rehder.); Pratt Apple tree (Malus prattii (Hemsl.) Schneid.); the Apple tree brown, riverside (Malus fusca (Raf.) Schneid.); Apple berry, Siberian (Malus baccata (L.) Borkh.); loringhoven Apple tree (Malus toringoides (Rehd.) Hughes). Study of water regime and drought tolerance of ornamental species of the genus Malus Mill. conducted by artificial wilting in 3-fold repetition on 10 leaves in each iteration. Drought resistance of crops were determined in the driest and hottest period, the average daily temperature during the experiment amounted to +24...+25 °C, relative humidity — 56 %. The leaves were collected in morning hours. In determining the water regime of leaves was calculated, the water content or water cut on the raw mass. All other parameters: water deficit, relative turgor, water-holding capacity was expressed by wet weight of a leaf in full prior to saturation. The water retention capacity of leaves was determined by limiting the loss of water at the time (in hours) of the completion of the process of wilting. The results of all studies were expressed by calculating the average value of each characteristic. The results of these studies showed that the most stable water regime and high index of drought resistance are two ornamental Apple trees — Apple berry and Apple Siebold. It is therefore recommended to use these species in the landscaping of the settlements in the climatic conditions of the Orenburg region, as the most resistant species to water stress and temperature of the study area.