Method for improving germination of rice seeds under salt stress and application

Abstract

The invention provides a method for improving germination of rice seeds under salt stress and application, and relates to the field of crop seed germination, in particular to application of melatonin and vitamin C. The use concentration of the melatonin is 10 micromol / L, 50 micromol / L, 100 micromol / L, 200 micromol / L and 300 micromol / L, and the use concentration of the vitamin C is 5 micromol / L, 10 micromol / L, 20 micromol / L, 30 micromol / L and 50 micromol / L. The combined concentration of the melatonin and the vitamin C is 200 [mu] mol / L and 30 [mu] mol / L, the germination rate and the germination potential are significantly improved after the melatonin and the vitamin C are applied for treatment under salt stress, the germination effect of the rice seeds is optimal after the rice seeds are treated for 7 days by the 200 [mu] mol / L melatonin and the 30 [mu] mol / L vitamin C, the inhibition effect of salt stress on the rice seeds can be significantly relieved, and the salt stress resistance of the rice is improved. Therefore, the invention provides a theoretical basis for researching the mechanism that melatonin and vitamin C improve rice seed germination under salt stress, and provides practical guidance for research on promotion of plant salt tolerance at the same time.

Description

Technical Field

[0001] The invention relates to the field of crop seed germination, and in particular to a method for improving rice seed germination under salt stress by using melatonin and vitamin C and application thereof. Background Art

[0002] Nippon Haru ( Oryza. Sativa L. spp. japonica ) is a rice variety, belonging to the japonica subspecies. Rice is one of the most important food crops in the world today, and more than half of the world's population relies on rice as their main food source. It is rich in nutrients such as carbohydrates, protein, B vitamins and minerals, and is an important source of energy for the human body. In addition, rice by-products such as rice husks and rice straw also have important uses. Rice husks can be used as fuel and industrial raw materials, and rice straw can be used for weaving, feed, and returning to the field to increase soil fertility. In 2023, the national rice planting area will be 434 million mu, and the cultivation of rice products and quality is related to the germination of rice seeds. The material metabolism of rice seed germination will affect the seed germination time, germination rate, and the accumulation of biomass in the later stage of seedlings and the formation of final yield.

[0003] Soil salinization is an increasingly serious global problem. Seeds are most sensitive to salt stress during the germination period. When the salt stress is high, the expression of hydrolases (including amylase, lipase, protease, etc.) and their activities in the seeds are significantly inhibited, and the energy and material supply required for germination are insufficient, which ultimately leads to uneven seed germination. Therefore, improving the germination of salt-stressed seeds can not only save seeds and reduce input costs, but also ensure planting density and determine the yield of mature plants.

[0004] Melatonin (MT), CAS No. 73-31-4, is an indole heterocyclic compound. Its chemical name is N -Acetyl-5-methoxytryptamine. In plants, melatonin is not only involved in the physiological and developmental processes of plants, such as stomatal movement, seed germination, growth, flowering, senescence and circadian rhythm, but it can also improve the stress resistance of plants. However, its application in improving rice seed germination under salt stress has not been reported.

[0005] Vitamin C is a water-soluble vitamin. Vitamin C can not only strengthen the physical fitness of plants, improve their immunity, prevent the invasion of harmful substances, and thus enhance the disease resistance of plants. It can also promote the healthy growth of crops. Vitamin C lays a solid foundation for increasing yield and improving quality. Summary of the invention

[0006] In order to solve the above problems, the present invention provides an application of melatonin and vitamin C to improve rice seed germination under salt stress. The present invention will provide a theoretical basis for studying the mechanism of action of melatonin and vitamin C in improving rice seed germination under salt stress.

[0007] In order to achieve the above object, the present invention provides the following technical solutions: The present invention has found that the application of melatonin and vitamin C has a significant effect on improving the germination of rice seeds under salt stress.

[0008] Furthermore, the salt stress concentration is 0 - 200 mmol / L.

[0009] Furthermore, the salt stress concentration is 200 mmol / L.

[0010] Furthermore, the melatonin is used at a concentration of 10 - 300 μmol / L.

[0011] Preferably, the melatonin is used at a concentration of 10 μmol / L, 50 μmol / L, 100 μmol / L, 200 μmol / L or 300 μmol / L.

[0012] Furthermore, the vitamin C is used at a concentration of 5 - 50 μmol / L.

[0013] Preferably, the vitamin C is used at a concentration of 5 μmol / L, 10 μmol / L, 20 μmol / L, 30 μmol / L or 50 μmol / L.

[0014] Preferably, the melatonin and vitamin C are used at concentrations of 200 μmol / L and 30 μmol / L.

[0015] Furthermore, the application is to improve the germination rate and germination potential of rice seeds under salt stress.

[0016] Furthermore, the salt comprises sodium chloride.

[0017] Furthermore, the variety of the rice seeds is Nipponbare.

[0018] Furthermore, the present invention also provides a method for improving rice seed germination under salt stress, the method comprising applying melatonin at a concentration of 10-300 μmol / L and vitamin C at a concentration of 5-50 μmol / L to the rice seeds under salt stress.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention applies melatonin and vitamin C to rice seeds under 200 mmol / L salt stress conditions, proving that the combination of melatonin and vitamin C can promote rice seed germination under salt stress, and the best rice seed germination effect is achieved when 200 μmol / L melatonin and 30 μmol / L vitamin C are treated for 7 days. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Figure 2: Phenotypic diagram of rice seeds treated with salt solutions of different concentrations at different times.

[0021] Figure 2 Figure 2: Statistical graph of seed germination rate of rice seeds at different times when treated with salt solutions of different concentrations.

[0022] Figure 3 Figure 2: Statistical graph of germination potential of rice seeds at different times when treated with salt solutions of different concentrations.

[0023] Figure 4 Figure 2: Phenotypic diagram of rice seeds treated with different concentrations of melatonin at different times under 200 mmol / L salt stress.

[0024] Figure 5 Figure 2: Statistical graph of seed germination rate of rice seeds treated with different concentrations of melatonin at different times under 200 mmol / L salt stress.

[0025] Figure 6 Figure 2: Statistical graph of seed germination potential of rice seeds treated with different concentrations of melatonin at different times under 200 mmol / L salt stress.

[0026] Figure 7 Figure 2: Phenotypic diagram of rice seeds treated with different concentrations of vitamin C, 200 μmol / L melatonin (MT) and 30 μmol / L vitamin C (Vc) at different times under 200 mmol / L salt stress.

[0027] Figure 8 Figure 2: Statistical graph of seed germination rate of rice seeds at different times under 200 mmol / L salt stress conditions treated with different concentrations of vitamin C, 200 μmol / L melatonin (MT) and 30 μmol / L vitamin C (Vc).

[0028] Fig. 9 Figure 2: Statistical graph of seed germination potential of rice seeds at different times under 200 mmol / L salt stress conditions treated with different concentrations of vitamin C, 200 μmol / L melatonin (MT) and 30 μmol / L vitamin C (Vc). DETAILED DESCRIPTION

[0029] To make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work premise belong to the scope of protection of the present invention. Reagents used in the present invention, unless otherwise specified, can all be purchased from the market.

[0030] In some embodiments, the present invention provides an application of melatonin and vitamin C to improve rice seed germination under salt stress, wherein the concentration of melatonin is 10 μmol / L, 50 μmol / L, 100 μmol / L, 200 μmol / L, 300 μmol / L, and the concentration of vitamin C is 5 μmol / L, 10 μmol / L, 20 μmol / L, 30 μmol / L, 50 μmol / L.

[0031] In one embodiment, in the present invention, the concentration of melatonin used is 200 μmol / L, and the concentration of vitamin C used is 30 μmol / L. Under this scheme, the germination rate of rice seeds under 200 mmol / L salt stress conditions reaches 99%, which can basically offset the damage to rice seeds caused by salt stress. The germination rate of rice seeds under 800 mmol / L salt stress conditions reaches 89%, which greatly alleviates the damage to rice seeds caused by high-concentration salt stress.

[0032] Example 1 (1) Dissolve melatonin in methanol solution and mix well to prepare melatonin solution; the concentrations of melatonin solutions are 0 μmol / L, 10 μmol / L, 50 μmol / L, 100 μmol / L, 200 μmol / L, and 300 μmol / L respectively.

[0033] (2) Dissolve vitamin C in distilled water and mix well to prepare melatonin solution; the concentrations of vitamin C solutions were prepared to be 0 μmol / L, 5 μmol / L, 10 μmol / L, 20 μmol / L, 30 μmol / L, and 50 μmol / L.

[0034] (3) Mix sodium chloride and distilled water to prepare sodium chloride solution; prepare sodium chloride solutions with concentrations of 0 mmol / L, 50 mmol / L, 100 mmol / L, 150 mmol / L, and 200 mmol / L respectively.

[0035] (4) Seed pretreatment: Rice (Nipponbare) seeds with full grains were selected as experimental materials for each repetition. They were disinfected with 2% sodium hypochlorite solution for 10 min. After disinfection, the seeds were washed with distilled water for 3-5 times. After washing, the seeds were soaked in distilled water at an appropriate temperature (28 °C) for 6 h. (5) Seed germination experiment: The surface of the seeds was wiped dry and evenly placed in a culture dish (9 cm in diameter) with two layers of filter paper. In experimental group 1, 10 mL of sodium chloride solution of different concentrations (0 mmol / L, 50 mmol / L, 100 mmol / L, 150 mmol / L, 200 mmol / L) was added to screen the sodium chloride concentration that significantly inhibited rice seed germination. In experimental group 2, 10 mL of melatonin of different concentrations (0 μmol / L, 10 μmol / L, 50 μmol / L, 100 μmol / L, 200 μmol / L, 300 μmol / L) was added to the 200 mmol / L sodium chloride solution screened in experimental group 1, and an equal amount of methanol solution was added to the control group. In experimental group 3, 10 mL of vitamin C of different concentrations (0 μmol / L, 5 μmol / L, 10 μmol / L, 20 μmol / L, 30 μmol / L, 50 μmol / L) was added to the 200 mmol / L sodium chloride solution screened in experimental group 1. μmol / L); Experimental group 4, based on experimental groups 2 and 3, 10 mL of 200 μmol / L melatonin and 30 μmol / L vitamin C were added. Each dish contained 30 seeds and repeated 3 times.

[0036] (6) Culture conditions: The culture dish was placed at 28°C, 89% humidity, and 150 µmol·m -2 ·s -1 , rice seeds were germinated under 12 / 12 h (light / dark) conditions.

[0037] (7) Statistics of seed germination rate: Starting from the addition of distilled water, the germination of rice seeds was counted every 24 hours (1 day, 2 days, 3 days, 4 days, 5 days, 6 days, and 7 days). The germination standard was germination length ≥ 1 mm. The germination rate of seeds was investigated every day until the 7th day, and the results were counted. The calculation method of seed germination rate was: germination rate (%) = (number of germinations / total number of seeds) * 100%; the calculation method of germination potential was: germination potential = (number of seeds germinated within seven days / total number of seeds tested) * 100%.

[0038] Experimental Results from Figure 1 , Figure 2It can be seen that the germination rate of rice seeds treated with different concentrations of salt solution showed a certain inhibition phenomenon. According to statistics, the rice seeds treated with 0 mmol / L sodium chloride solution began to germinate from the 1st day, and its germination rate gradually increased over time. On the 3rd day, its germination rate reached 99.6%, and remained unchanged until the 7th day; the rice seeds treated with 50 mmol / L sodium chloride solution began to germinate from the 1st day, and its germination rate was 97% on the 7th day; the rice seeds treated with 100 mmol / L sodium chloride solution began to germinate from the 1st day, and its germination rate was 86% on the 7th day; the rice seeds treated with 150 mmol / L sodium chloride solution did not germinate on the 1st day, and the germination was significantly inhibited; the rice seeds treated with 200 mmol / L sodium chloride solution did not germinate until the 3rd day, and its germination rate was 16% on the 7th day, and the germination was seriously inhibited. (Note: The germination rate of rice seeds treated with 0mmol / L sodium chloride solution failed to reach 100%, which may be due to the quality of rice seeds) According to statistics, Figure 3 It can be seen that the germination potential of rice seeds treated with 0 mmol / L sodium chloride solution was 99.6% within 7 days; the germination potential of rice seeds treated with 50 mmol / L sodium chloride solution was 97.3% within 7 days; the germination potential of rice seeds treated with 100 mmol / L sodium chloride solution was 86% within 7 days; the germination potential of rice seeds treated with 150 mmol / L sodium chloride solution was 43.6% within 7 days; and the germination potential of rice seeds treated with 200 mmol / L sodium chloride solution was 16% within 7 days. Therefore, 200 mmol / L sodium chloride solution was selected for subsequent experiments.

[0039] See also Figure 4 , Figure 5 In the presence of 200 mmol / L sodium chloride, the germination rate of rice seeds was alleviated to a certain extent by treating them with different concentrations of melatonin. As the concentration increased, the alleviation effect increased, and 200 μmol / L melatonin had the best effect, with the germination rate reaching 97.8% at 7 days. However, when treated with 300 μmol / L melatonin, the germination rate decreased to 54%.

[0040] See also Figure 6 According to statistics, the germination potential of rice seeds under salt stress treated with 200 μmol / L melatonin was 97.8%, which was 81.8% higher than that of rice seeds under salt stress.

[0041] See also Figure 7 , Figure 8In the presence of 200 mmol / L sodium chloride, rice seeds were treated with different concentrations of vitamin C, and the germination rate increased. With the increase of concentration, the effect of alleviating salt stress was enhanced, among which 30 μmol / L vitamin C had the best effect, and its germination rate reached 91% at 7 days, but when treated with 50 μmol / L vitamin C, the germination rate decreased to 41%, so the optimal vitamin C concentration for alleviating salt stress was 30 μmol / L. In addition, when treated with 200 μmol / L melatonin and 30 μmol / L vitamin C, the effect of alleviating salt stress was stronger than that of melatonin and vitamin C alone, and its germination rate reached 99% at 7 days.

[0042] See also Fig. 9 According to statistics, the germination potential of rice seeds under salt stress treated with 30 μmol / L vitamin C was 91%, which was 75% higher than that of rice seeds under salt stress. When treated with 200 μmol / L melatonin and 30 μmol / L vitamin C, the germination potential of rice seeds was 99%, which was 83% higher than that of rice seeds under salt stress.

[0043] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. Application of melatonin and vitamin C in improving rice seed germination under salt stress.

2. The use according to claim 1, characterized in that: The salt stress concentration is 0 - 200 mmol / L.

3. The use according to claim 2, characterized in that: The salt stress concentration is 200 mmol / L.

4. The use according to claim 1, characterized in that: The melatonin is used at a concentration of 10 - 300 μmol / L.

5. The use according to claim 4, characterized in that: The melatonin is used at a concentration of 10 μmol / L, 50 μmol / L, 100 μmol / L, 200 μmol / L or 300 μmol / L.

6. The use according to claim 1, characterized in that: The vitamin C is used at a concentration of 5 - 50 μmol / L.

7. The use according to claim 6, characterized in that: The vitamin C is used at a concentration of 5 μmol / L, 10 μmol / L, 20 μmol / L, 30 μmol / L or 50 μmol / L.

8. The use according to any one of claims 1 to 7, characterized in that: The application is to improve the germination rate and germination potential of rice seeds under salt stress.

9. The use according to claim 8, characterized in that: The variety of the rice seeds is Nipponbare.

10. A method for improving rice seed germination under salt stress, characterized in that: The method comprises applying melatonin with a concentration of 10-300 μmol / L and vitamin C with a concentration of 5-50 μmol / L to rice seeds under salt stress.

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