MECHANISMS OF PLANT ADAPTATION TO OIL POLLUTION

Abstract

The problem of soil technogenic contamination with oil and the adaptation mechanisms of various plants to adverse growth environments are discussed. Tolerant plant species were discovered, in particular, cereal Carex hirta L., hairy sedge, and a number of legumes (clover, alfalfa, beans and soy). It was shown that the oil pollution effects in plants initiates a cascade of changes achieved by restructuring of the morphological and physiologically-biochemical adaptation mechanisms, in particular increases the carotenes, phenols, proline concentrations, disturbed hormonal balance, stress proteins synthesis, etc. This is an evidence of physiological adaptation of the tolerant to oil pollution plants. Visible changes occur due to a decrease of the above-ground parts growth parameters and an active development of root system. Meantime, the root system plays a key role in stress adaptation of plants.
Studies of physiologically-biochemical adaptation pathways of plants tolerant to oil pollution are important to create the scientific basics of restoration strategy for oil and petroleum products contaminated areas. Carex hirta L. plants have been found to accelerate oil biodegradation process, promote the growth of number of basic physiological groups of rhizosphere microorganisms and provide favorable environment for the further growth of leguminous plants on these soils. This provides a reason to recommend for the phytoremediation of areas contaminated with oil and petroleum products the long-rhizome Carex hirta L. as one of environmentally plastic and viable species. In turn, legume plants due to the symbiotic nitrogen fixation ability, increase biochemical activity of the soil, that leads to it’s self-cleaning. Two Patents were obtained on that regard (2006, 2011).