Method for generating radiation effect on plants by low-dose-rate gamma radiation

Abstract

The invention relates to a method for generating a radiation effect on plants by low-dose-rate gamma radiation, and belongs to the technical field of biological radiation. Comprising a plant screening mode plant, a food chain related plant and an ICRP recommended reference organism. And a gamma irradiation source selected for gamma irradiation is 60Co or 137Cs. And the gamma irradiation dose rate is less than 50mGy / h. The implementation effect of the method shows that the antioxidant enzyme system of arabidopsis thaliana can be activated by low-dose-rate irradiation. The method provides an important basis for evaluating the influence of low-dose radiation on the plant biological effect. In the future, low-dose-rate irradiation can be further expanded to be used for adjusting a complex relation between plant population ecological effects and mining adaptive application of plants under radiation stress, for example, a method for monitoring adverse effects of nuclear facility effluents on plant populations can be established through the method, and the method plays a positive role in ecological system stability. Meanwhile, the method disclosed by the invention can be used for plant stress tolerance breeding or seed selection.

Description

Technical Field

[0001] The present invention relates to the field of biological radiation technology and a method for producing radiation effects on plants by low-dose rate gamma irradiation. Background Art

[0002] With the continuous development of nuclear energy, the risk of radioactive contamination in the environment increases, especially after long-lived nuclides settle into the soil, they will damage the normal growth and development of plants, thus not only changing the characteristics of the population, but also destroying its temporal dynamics and changing the genetic structure of the population. These changes may in turn change the composition of the community and the interaction between species (Reference 1: S. Geras'kin, T. Evseeva, A. Oudalova. Effects of long-term chronic exposure to radionuclides in plant populations. Journal of Environmental Radioactivity. 2013, 121 (jul.): 22-32.). Therefore, to establish an environmental radiation protection system, more research data on the radiation effects of low-level exposure of radionuclides on plant and animal populations are needed.

[0003] In 2007, ICRP's new recommendations added the content of environmental protection (i.e., radiological protection of non-human species) (Reference 2: ICRP. The 2007 Recommendation of the International Commission on Radiological Protection [R]. ICRP Publication-103, 2007). As early as the 1990s, my country issued the "Outline of China's Nature Conservation" and "China's Agenda 21", which clearly put forward the requirements for protecting non-human species. The "Radioactive Pollution Prevention and Control Law" promulgated in 2003 also focused on the protection of the environment and the prevention and control of radioactive pollution. It can be seen that it is very necessary to carry out research on the effects and evaluation of ionizing radiation on non-human species in my country.

[0004] γ-irradiation can cause mutations in peroxidase activity, such as Gao Jian et al. 60The physical mutagenesis method of Coγ-rays explored the cellular basis and molecular mechanism of morphological mutation, and analyzed the physiological and biochemical mutagenesis effects caused by γ-ray irradiation (Reference 3: Gao Jian. Study on the mutagenic effect and mechanism of cobalt-60Gamma-ray irradiation on Chinese narcissus [D]. Beijing: Chinese Academy of Forestry, 2000.) The single-petal variety of Chinese narcissus (Narcissus tazettavar. Chinese Roem) in Zhangzhou, China. Studies have shown that abiotic stress can induce the production of excessive reactive oxygen species (ROS), causing membrane lipid peroxidation and damage to the integrity of chloroplast structure (Reference 4: Gupta DK, A,Semenishchev VS,et al.Uranium accumulat ion and its phytotoxicitysymptoms in Pisum sativum L.[J].Environmental Science and Pol lut ionResearch International,2020,27(3):3513-3522). On the contrary, plants will enhance plant tolerance or adaptability by regulating changes in osmotic regulating substances such as proline (Pro), reactive oxygen scavenging systems such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione reductase (GR), etc. (Reference 5: Wu Juan, Shi Guoxin, Xia Haiwei, et al. Regulatory effects of exogenous calcium on the antioxidant system and proline metabolism of Potamogeton crispus L. leaves under mercury stress [J]. Journal of Ecology, 2014, 2: 380-387. Reference 6: O'Brien JA, Daudi A, Butt VS, et al. Reactive oxygen species and their role in plant defence and cell wall metabolism [J]. Planta, 2012, 236 (3): 765-779.). Malondialdehyde (MDA), a byproduct of lipid peroxidation, reflects the extent of damage suffered by plants under adverse conditions. Studies have shown that the MDA content in poinsettia plants is lowest when irradiated with 70 Gy, while it is highest when irradiated with 20 Gy (Reference 7: Lei Xiao, Qiang Jiye, Chen Yunfei. 60Effects of Co-γ-ray radiation on malondialdehyde and several protective enzymes in poinsettia [J]. Journal of Yunnan Agricultural University, 2006 (06): 855-858.). Chlorophyll fluorescence is closely related to the various reaction processes in photosynthesis. The effect of any adversity on photosynthesis can be reflected by the changes in the chlorophyll fluorescence induction dynamics in vivo (Reference 8: Bourne-worster S, Feighan O, Manby F R. Charge transfer as a mechanism for chlorophyl l fluorescence concentration quenching [J]. Proceedings of the National Academy of Sciences of the United States of America, 2023, 120 (5): e2210811120.). A certain dose of radiation treatment can increase the germination rate of bamboo seeds and the fluorescence parameter values ​​related to photosynthesis of seedlings (Reference 9: Guo Shaoling, Gao Jian, Xu Youming, et al. 60 Effects of Co-γ radiation on endogenous hormone content during germination of bamboo seeds[J]. Chinese Agricultural Science Bulletin, 2013, 29(25): 26-31.) 60 Co-γ-ray radiation can increase the chlorophyll content in the leaves of Tillandsia odorifera and enhance plant photosynthesis (Reference 10: Xu Yinlian, Qiang Jiye. 60 Effects of Co-C ray radiation on some physiological parameters of Tillandsia odorifera[J]. Journal of Seed Science, 2005, 24(4):26-30.). Therefore, the oxidative damage index malondialdehyde (MDA), osmotic regulating substance proline, antioxidant enzyme system, photosynthetic pigments, and chlorophyll fluorescence parameters can be used as indicators of plant stress response under γ-ray irradiation conditions.

[0005] Currently, research on the effects of ionizing radiation on plant physiological characteristics mainly focuses on high-dose radiation breeding, while research on the radiation effects on plants after relatively low-dose rate irradiation is relatively rare. Summary of the invention

[0006] The purpose of the present invention is to establish a method for producing radiation effects on plants after relatively low dose rate irradiation, so as to solve the problems of lack of existing data and unclear research methods, and provide a basis for subsequent evaluation of plant radiation biological effects and population ecological impacts after gamma irradiation.

[0007] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] A method for producing radiation effects on plants by low-dose rate gamma irradiation comprises the following steps:

[0009] 1) Plant screening includes: model plants, plants related to the food chain, or reference organisms recommended by ICRP;

[0010] 2) γ irradiation: The γ irradiation source is selected as 60 Co or 137 Cs;

[0011] 3) The irradiation dose rate is less than 50mGy / h.

[0012] The plants selected in the method of the present invention are Arabidopsis thaliana, cereal plants, root and tuber plants, fruit plants, large terrestrial plants, small terrestrial plants or seaweed.

[0013] The plant selected in the method of the present invention is Arabidopsis thaliana.

[0014] In the method of the present invention, the irradiation source selected is a gamma irradiation source. 137 Cs.

[0015] The present invention provides a method for producing radiation effects on plants by low-dose rate gamma irradiation. Specifically, it is a method for using gamma irradiation to represent the external radiation received by plants and the radiation effects that may be caused to plants. Other studies on simulated irradiation conditions may refer to this method.

[0016] From the implementation effect of the present invention, the effect of low-dose rate irradiation on Arabidopsis is to activate the antioxidant enzyme system of Arabidopsis. When the dose rate is less than 50mGy / h, Arabidopsis can cope with low-dose rate γ irradiation by regulating the light capture efficiency and conversion efficiency of catalase, peroxidase, superoxide dismutase, and PSII reaction center. The results of the present invention not only reveal the specific effects of different dose rate γ irradiation on the growth, development and physiological characteristics of the first generation of Arabidopsis, but also provide an important basis for evaluating the effects of low-dose radiation on plant biological effects.

[0017] The method of the present invention for the radiation effect of low-dose rate gamma irradiation on plants solves the problems of lack of existing data and unclear research methods in this field. It is universal for different types of plants, can simulate low-dose rate gamma irradiation, set different dose rates, and provide a scientific basis for the subsequent evaluation of plant radiation biological effects and population ecological impacts after gamma irradiation.

[0018] In the future, the method of the present invention can be further extended to low-dose rate irradiation for the adjustment of complex relationships between ecological effects of plant populations, as well as the adaptive application of plants under radiation stress. For example, the method can be used to establish a monitoring method for the adverse effects of nuclear facility effluent on plant populations, which has a positive effect on the stability of the ecosystem. At the same time, the method of the present invention can be used for plant stress tolerance breeding or seed selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 different 137 Effects of Cs-γ Dose Rate Irradiation on Catalase in Arabidopsis thaliana

[0020] Figure 2 different 137 Effects of Cs-γ Dose Rate Irradiation on Peroxidase in Arabidopsis

[0021] Figure 3 different 137 Effects of Cs-γ Dose Rate Irradiation on Superoxide Dismutase in Arabidopsis

[0022] Figure 4 different 137 Effects of Cs-γ dose rate irradiation on effective photochemical quantum yield of Arabidopsis thaliana

[0023] Figure 5 different 137 Effect of Cs-γ dose rate irradiation on the maximum photochemical quantum yield of Arabidopsis thaliana. DETAILED DESCRIPTION

[0024] The present invention is further described in conjunction with specific embodiments, but these embodiments are only intended to illustrate the present invention and are not intended to limit the scope of the present invention.

[0025] Implementation case: different dose rates 137 Experimental Study on the Radiation Effects of Cs-γ Irradiation on Arabidopsis

[0026] (1) Plant screening: The plant selected was the model plant Arabidopsis thaliana.

[0027] (2) γ irradiation: The selected γ irradiation source is 137 Cs, the selected total dose was 1Gy, and the selected dose rates were 0mGy / h, 10mGy / h, 20mGy / h, 50mGy / h, and 100mGy / h. Under each treatment, 6 parallel samples were taken.

[0028] Measuring peroxidase, catalase and other indicators

[0029] (3) Index determination: Sampling was carried out during the flowering period of Arabidopsis thaliana. Six plants were collected from each of the five dose rate treatments of 0 mGy / h to 100 mGy / h, and the sampling was repeated six times. The plant phenotypes measured were plant height, basal leaf length, and basal leaf width. The plant physiological and biochemical indicators measured were superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione reductase (GR), malondialdehyde (MDA), and proline (Pro). The plant fluorescence parameters measured were the effective photochemical quantum yield of photosystem II (PSII), the maximum photochemical quantum yield of PSII Fv / Fm, and the non-photochemical quenching coefficient NPQ.

[0030] (4) Data analysis: SPSS 17.0 was used for data analysis to conduct one-way ANOVA test and LSD multiple comparison on the differences of plants after irradiation, and Excel was used for graphing.

[0031] Test results:

[0032] The differences obtained through data analysis 137 Effects of Cs-γ dose rate irradiation on catalase in Arabidopsis thaliana Figure 1 Catalase is an important antioxidant protein that removes excess H2O2 to the outside of the cell to maintain the balance of H2O2 within the cell and protect the cell membrane. Figure 1 The specific activity of catalase decreased first and then increased with the increase of dose rate, reaching the lowest value at 20mGy / h.

[0033] different 137 Effects of Cs-γ dose rate irradiation on peroxidase in Arabidopsis thaliana Figure 2 Peroxidase can convert H2O2 into H2O, thereby reducing reactive oxygen species and alleviating the damage of membrane lipid peroxidation to cell membranes. Figure 2 Except for the 50mGy / h group, the other dose rate conditions would lead to a significant increase in the peroxidase activity of the plants, thereby reducing the damage of membrane lipid peroxidation to the cell membrane.

[0034] different 137 Effects of Cs-γ dose rate irradiation on superoxide dismutase in Arabidopsis thaliana Figure 3 Superoxide dismutase (SOD) can dismutate superoxide anions to produce H2O2 and O2. Figure 3 The specific activity of superoxide dismutase decreased first and then increased with the increase of dose rate, reaching the lowest value at 20mGy / h.

[0035] different 137 Effects of Cs-γ dose rate irradiation on the effective photochemical quantum yield of Arabidopsis thaliana Figure 4 The effective photochemical quantum yield reflects the efficiency of capturing primary light energy by the open PSII reaction center, and the trend can be used to determine whether there is an abnormality in the photosynthetic system of the plant. Figure 4 The effective photochemical quantum yield of Arabidopsis offspring irradiated with 50mGy / h was significantly lower than that of offspring irradiated with 0mGy / h, 10mGy / h, and 100mGy / h.

[0036] different 137 Effects of Cs-γ dose rate irradiation on the maximum photochemical quantum yield of Arabidopsis thaliana Figure 5The maximum photochemical quantum yield reflects the light energy conversion efficiency in the PSII reaction center or the maximum PSII light energy conversion efficiency. Under non-stress conditions, this parameter changes very little and is not affected by species and growth conditions. The range of variation is 0.75-0.85. Under stress conditions, this parameter decreases significantly. Figure 5 The γ-ray irradiation treatments at different dose rates did not cause significant effects on the photosynthetic system of the offspring Arabidopsis thaliana.

[0037] From the results, the effect of low-dose rate irradiation on Arabidopsis is to activate the antioxidant enzyme system of Arabidopsis. When the dose rate is less than 50mGy / h, Arabidopsis can cope with low-dose rate γ irradiation by regulating the light capture efficiency and conversion efficiency of catalase, peroxidase, superoxide dismutase, and PSII reaction center. The results of this study not only revealed the specific effects of different dose rate γ irradiation on the growth, development and physiological characteristics of Arabidopsis offspring, but also provided an important basis for evaluating the effects of low-dose radiation on plant biological effects. In the future, it can be further expanded to low-dose rate irradiation for the adjustment of complex relationships between ecological effects of plant populations, as well as to explore the adaptive application of plants under radiation stress. For example, this method can be used to establish a monitoring method for the adverse effects of nuclear facility effluent on plant populations, which has a positive effect on the stability of the ecosystem. At the same time, the method of the present invention can be used for plant stress tolerance breeding or seed selection.

Claims

1. A method for producing radiation effects on plants by low-dose rate gamma irradiation, comprising the following steps: 1) Plant screening includes: Model plants, plants related to the food chain, or reference organisms recommended by ICRP; 2) γ irradiation: The γ irradiation source is selected as 60 Co or 137 Cs; 3) The irradiation dose rate is less than 50mGy / h.

2. The method of producing radiation effects on plants by low-dose rate gamma irradiation according to claim 1, characterized in that: The selected plants are Arabidopsis thaliana, cereal plants, root plants, fruit plants, large terrestrial plants, small terrestrial plants or seaweed.

3. A method for producing radiation effects on plants by low-dose rate gamma irradiation according to claim 1 or 2, characterized in that: The plant of choice was Arabidopsis thaliana.

4. A method for producing radiation effects on plants by low-dose rate gamma irradiation according to claim 1 or 2, characterized in that: The γ irradiation source used for irradiation is 137 Cs.

5. The method of producing radiation effects on plants by low-dose rate gamma irradiation according to claim 3, characterized in that: The γ irradiation source used for irradiation is 137 Cs.

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