Effect of Crude Oil on Growth, Oxidative Stress and Response of Antioxidative System of Two Rye (Secale cereale L.) Varieties

Abstract

Rye (Secale cereale L.) is one of the most important cereal crops in Eastern and Northern Europe, showing better tolerance to environmental stress factors compared to wheat and triticale. Plant response to the crude oil-polluted soil depends on plant species, oil concentration, time of exposure, etc. The current study is aimed at investigating the growth, oxidative stress and the response of antioxidative system of two rye varieties (Krona and Valdai) cultivated on crude oil-contaminated soils at different concentrations (1.5, 3.0, 6.0, and 12.0%). Inhibition of rye growth was observed at crude oil concentrations of above 3% for above-ground plant parts and of above 1.5% for roots. A decrease in content of chlorophyll a and total chlorophylls in Krona variety was detected at 1.5% oil concentration in soil and in Valdai variety at 3% oil concentration. Compared with the control, the content of malondialdehyde was significantly increased in the Krona variety at 3% oil concentration and in Valdai variety at 6% oil concentration. The crude oil-induced oxidative stress was minimized in rye plants by the enhanced contents of low-molecular antioxidants (proline, non-protein thiols, ascorbic acid, phenolic compounds) and activities of superoxide dismutase, catalase, ascorbate peroxidase, and glutathione peroxidase. The strongest positive correlation was detected between the content of malondialdehyde and contents of proline (r = 0.89–0.95, p ≤ 0.05) and phenolic compounds (r = 0.90–0.94, p ≤ 0.05) as well as superoxide dismutase activity (r = 0.81–0.90, p ≤ 0.05). Based on the results of a comprehensive analysis of growth and biochemical parameters and of the cluster analysis, Valdai variety proved to be more resistant to oil pollution. Due to this, Valdai variety is considered to be a promising rye variety for cultivation on moderately oil-polluted soils in order to decontaminate them. At the same time, it is necessary to conduct further studies aimed at investigating oil transformation processes in the soil-rye system, which would make it possible to determine the efficiency of using this cereal for soil remediation.

Potentiality of Azolla pinnata R. Br. for Phytoremediation of Polluted Freshwater with Crude Petroleum Oil

“…Preliminary tests in a previous study [53] estimated the phytotoxic effects of high petroleum hydrocarbon concentrations on Azolla pinnata. This marked decline in TPH degradation by A-A is due to the destructive effects of petroleum compounds on many living organisms [43,54,55]. However, the 21-day results show that the rates of TPH removal in the unplanted and planted waters were higher than that in the 14-daygrowth period, but they are lower than that the results obtained after 7days.…”

Oil Pollution Affects the Central Metabolism of Keystone Vachellia (Acacia) Trees

“…For example, cowpea (Vigna unguiculata L.) seedlings exposed to crude oil showed induction in free sugar, total protein, and amino acid levels and a reduction in chlorophyll contents in the leaves [21]. Biomass and chlorophyll content in the leaves of two rye (Secale cereale L.) variants exposed to crude oil-polluted soil decreased, while the levels of the amino acid proline and oxidative stress parameters, such as enzyme activity and antioxidant content, increased in a variant-dependent manner [57]. Similarly, three-month-old jojoba (Simmodsia chinensis Link) plants, growing in oil-polluted soil, had reduced chlorophyll contents in their leaves and increased total carbohydrates, total proteins, amino acids, and proline in their plant shoots [58].…”

Influence of Hydrocarbon-Oxidizing Bacteria on the Growth, Biochemical Characteristics, and Hormonal Status of Barley Plants and the Content of Petroleum Hydrocarbons in the Soil

“…inhibit their growth. There is an opinion [ 19 , 20 ], that the main indicator of the detrimental effect of petroleum hydrocarbons on plants is growth retardation leading to a decrease in biomass. Throughout the experiment, oil exerted an inhibitory effect on all analyzed parameters of the growth and development of barley plants, which could be explained by its direct toxic effect [ 21 , 22 ].…”

“…It participates in the regulation of the osmotic potential of cells, stabilizes the cell structure, and removes excess ROS, thereby increasing the resistance of plants to stress [ 62 ]. Data on changes in the level of this amino acid in plants at different concentrations of oil in the soil are quite contradictory and are determined both by the type of pollutant and the type (and even variety) of plants [ 20 ]. For example, the presence of diesel fuel and gasoline in soil has been shown to increase the accumulation of this amino acid in wheat plants, while pollution with oil products caused its decrease in the leaves of bean plants [ 63 , 64 ].…”