Structure

Phone: (+994 12) 5102681
Fax:
E-mail: elimkhan.jafarov@gmail.com

Head of the Laboratory is: Doctor of Biological Sciences, Professor Jafarov Elimkhan Suleyman oglu

Total number of employees: 14

The main activities of the laboratory are:
Studying the mechanisms of radiation and many stress factors' effects on biological systems. Development of scientific bases for radiation safety issues.

The main scientific results of the laboratory are:
1. The qualitative and quantitative composition of radionuclides was determined, and their distribution regularities were studied both on individual soil profiles and on the horizontal plane in one of the local contamination zones of the Absheron Peninsula (on the territory of the Ramani iodine plant). We studied both the migration of radionuclides polluting the territory along the earth-plant chain and the features of their accumulation in individual plant organs. Also, the effect of ionizing radiation caused by radionuclides polluting the area on the biomorphological and reproductive characteristics of grass plants formed in the wild under chronic exposure conditions, the photosynthesis process sensitive to these conditions, and the functioning of the antioxidant defense system of plants were studied.
2. The effect of ionizing radiation on the growth and development of both themselves and the first generations of beans, eggplant, cucumber and tomato, whose seeds were treated with different doses of gamma rays before sowing, the dynamics of dose-dependent changes in the amount of malonodialdehyde (MDA) - product lipid peroxidation formed in the leaves of plants under conditions of radiation stress, as well as the dynamics of dose-dependent changes in the amount of proline - an antioxidant that plays the role of a "trap" for active oxygen, and the effect of different doses of ionizing radiation on the antioxidant defence system (ADS) of plants were studied on the basis of the determination of the activities of antioxidant enzymes such as ascorbate peroxidase (APX), catalase (CAT) and superoxide dismutase (SOD).
      It is established that there are obvious differences in the biometric sizes of the fruits of the first generation of the studied plants in comparison with both parent and control fruits; as the radiation dose increases, membrane lipids undergo more “destruction”, and as a result, MDA content increases. The amount of proline varies depending on the dose. Under conditions of radiation stress, in addition to proline, antioxidant enzymes of the antioxidant defense system, such as SOD, CAT, and APX, are also actively involved in protecting plants from the harmful effects of ionizing radiation. Primary damage caused by radioactive radiation is transferred to the next generation only in special cases.
      Based on the results obtained, it was revealed that increasing the dose in the low-dose region enhances the generation of active forms of oxygen, as a result of which the cell membranes are exposed to larger-scale destruction. In such conditions, the antioxidant defense system of plants, along with the acceleration of the synthesis of antioxidants such as proline, also causes the activation of antioxidant enzymes. In large doses, the destructive effect, along with lipids, covers the biological macromolecules themselves.
3. Considering that plants grow under the influence of several extreme environmental factors and that such effects can lead to a decrease in the productivity of cultivated plants and a decrease in the biodiversity of wild plants, the growth and development of certain grain crops (peas, beans, and corn) in various concentrations of NaCl were studied, the seeds of which were treated with γ rays in different doses, and based on the synthesis of chlorophylls and quantitative changes in carotenoids, some clarity was brought to the process of photosynthesis under the conditions of dual stress. To assess the “destruction” caused by active forms of oxygen in cell membranes under dual stress, the dynamics of changes in malondialdehyde (MDA), the main product of membrane lipid peroxidation, as well as total protein depending on the radiation dose and NaCl concentration, were studied. The functioning of the antioxidant defense system of pea, bean, and corn plants under the conditions of radiation and salt stress separately and together was evaluated based on the dynamics of changes in the amount of small-molecule antioxidants such as proline, carotenoids, anthocyanins, and flavonoids and the activities of antioxidant enzymes such as SOD, CAT, and APX of this system depending on the radiation dose and the concentration of NaCl.
It is established that for peas and corn:
- both for seeds irradiated with different doses and for seeds grown in different concentrations of NaCl, there is a clear dependence of plant growth and development on both the radiation dose and the salt concentration in stressful situations;
- in such conditions, the antioxidant defense system of the plant is activated, and both antioxidant enzymes and small-molecule antioxidants of the mentioned system participate in this activation;
-an increase in radiation dose causes changes in the activation of antioxidant enzymes. These changes at different concentrations of NaCl are different. Thus, SOD activity decreases at NaCl concentrations of 1, 5, and 10 mM, and the activities of CAT and APX increase, not counting minor deviations. However, at salt concentrations of 50 and 100 mM, on the contrary, there is a decrease in the activities of CAT and APX and an increase in SOD activity, i.e., under stress conditions, antioxidant enzymes in some way show balanced activity;
- functioning of AODS in stress conditions causes acceleration of the synthesis of stress proteins with an increase in radiation dose, and the increasing trend observed at high radiation doses becomes larger in the high-concentration salt environment;
- the same dynamics of change are characteristic of carotenoids. Thus, an increase in both radiation dose and salt concentration results in an increase in the amount of these pigments. It is believed that an increase in the number of carotenoids under the combined effect of radiation and salt stress is an adaptive response of plant cells to stressful conditions;
- unlike carotenoids, anthocyanins are characterized by an increase in the low dose range and a decrease in the high dose range. The dynamics of change in this form are maintained at almost all concentrations of NaCl. Only at low salt concentrations, this change has a steep resonance character;
- From our results on green pigments, what is more striking is that the studied plant has a higher content of Xl a than Xl b. As for the dynamics of changes depending on the radiation dose and the salt concentration, it is clear that the increase in the radiation dose at low concentrations of NaCl leads to a significant increase in Xl a and a slight increase in Xl b. And at high salt concentrations, an increase in the radiation dose does not cause noticeable changes in the amount of green pigment. Considering the fact that plant growth and development are organically linked to the synthesis of green pigment, it can be considered that the combined effect of stress factors causes a more inhibitory than stimulating effect;
- the well-coordinated activity of antioxidant enzymes and small-molecule antioxidants ensures effective protection of plants against the damaging effects of stress factors;
- in such conditions, depending on the intensity of stress factors, the antioxidant enzymes of the antioxidant defense system of the plants perform a balanced and correlative activity both among themselves and with small molecule antioxidants, which protects the plants from the harmful effects of stress factors. It is believed that determining the details of the mechanism of the formation of adaptation features in plants to such conditions opens wide perspectives in the selection of plant species that can show high resistance to stress factors, increasing the resistance of plants to the effects of stress factors, and how these processes can be controlled.
4. The effect of pre-sowing treatment with high doses of 0.3, 0.5, 1, 1.5, and 2 kGy (sterilization doses) on the growth and development of potatoes, beans, eggplants, cucumbers, and tomatoes was studied, and based on the changes in the content of photosynthetic pigments and changes in the dynamics of small and large-molecule antioxidants, the effect of high-dose radiation on photosynthesis and on the functioning of the antioxidant defense system was evaluated. It was determined that:
- the lethal dose range of gamma radiation treatment of seeds before sowing is 0.3 - 2 kGy for potatoes, 0.5 - 2 kGy for beans, cucumbers, and tomatoes, and 1 - 2 kGy for eggplant. It is believed that although sterilization doses of 0.3 kGy and more ensure the long-term storage of potatoes in terms of the destruction of microorganisms, these doses cannot ensure the use of potato seeds for the subsequent sowing;
- a dose of 0.3 kGy accelerates the synthesis of chlorophyll a and b in eggplant; these doses have virtually no effect on the synthesis of these pigments in beans and tomatoes; and it accelerates the synthesis of chlorophyll b while inhibiting the synthesis of chlorophyll a in cucumber;
- the amount of MDA in plants whose seeds were not subjected to radiation increases, respectively, in a row: beans, cucumbers, tomatoes, and eggplants;
- beans and eggplants from the control plants in which the seeds were not treated with γ rays before sowing contain approximately the same amount and relatively more protein content, and seed treatment with γ rays before sowing cannot significantly change the protein content;
- the amount of carotenoids is higher in the control sample of tomatoes than in the control sample of beans. An increase in the amount of carotenoids is observed in the process of treating the seeds of bean and tomato plants with radioactive rays. Treatment of seeds with radioactive rays before sowing cannot change the amount of these pigments in cucumber, while in eggplant, the increase in radiation dose leads to a first small and then a sharp decrease in the amount of yellow pigments;
- treatment of seeds with radioactive rays at a dose of 0.3 kGy stimulates the synthesis of anthocyanins and proline in all plants;
- the control sample of cucumber has high APX and CAT activity, and the irradiation of seeds in all the studied plants reduces the activity of these enzymes;
- both control and test samples of the studied plants demonstrate similar activity in APX and CAT; in other words, these enzymes play a similar role in the functioning of the antioxidant defense system;
- beans, tomatoes, and eggplants, which have low APX and CAT activity, show high SOD activity, and cucumbers, which, on the contrary, have high APX and CAT activity, have low SOD activity. In other words, the action of antioxidant enzymes in plants is balanced in a certain sense.