A method for improving the adaptability of soybeans to saline-alkali land

Abstract

The present invention provides a method for improving the adaptability of soybeans to saline-alkali land, belonging to the technical field of crop stress resistance research. The method for improving the adaptability of soybeans to saline-alkali land in the present invention includes: before sowing, soaking the seeds with a rare earth lanthanum-salicylic acid mixed solution; at the three trifoliate leaf stage of soybeans, spraying brassinolide on the stems and leaves. By jointly soaking the seeds with rare earth lanthanum and salicylic acid, the present invention improves the seed germination ability of soybeans in saline-alkali land, increases the germination rate, germination potential and germination index; by spraying brassinolide, the saline-alkali resistance of soybeans is improved, the activities of SOD, POD and CAT of soybean seedlings are increased, and the MDA content of soybean seedlings is reduced; the yield and quality of soybeans under saline-alkali environment planting are guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of crop stress resistance research, and particularly relates to a method for improving the adaptability of soybeans to saline-alkali land. Background Art

[0002] Soybeans originated in China and have a planting history of more than 4,000 years in China. They provide rich oil and protein for people's daily life and are important economic food crops in China.

[0003] Soybeans are moderately salt-tolerant crops. Saline conditions seriously affect soybean growth, agronomic traits, and seed quality, resulting in reduced soybean yields. Some studies have shown that salinity reduces the germination rate and emergence rate of soybean seeds; affects the traits of soybean plants and reduces root activity; it also leads to a decrease in soybean grain yield. For sensitive varieties, it also affects soybean quality and reduces the crude protein and crude fat content of soybean grains.

[0004] For improving the salt-alkali resistance of soybeans, measures include breeding salt-alkali-resistant varieties, improving saline-alkali land, and chemical control. However, breeding salt-alkali-resistant varieties requires a very long time, and improving saline-alkali land also needs to be carried out continuously for many years, consuming a large amount of manpower and material resources. Therefore, improving the salt-alkali resistance of soybeans through chemical control is a convenient and time-effective method. However, for the related research on improving the salt-alkali tolerance of soybeans through chemical control, most are single agents and single measures, with limited improvement in the salt-alkali tolerance of soybeans. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method for improving the adaptability of soybeans to saline-alkali land. By soaking seeds and carrying out chemical control at the three trifoliate leaf stage, it can improve the germination ability of soybeans planted in saline-alkali land, improve the salt-alkali resistance of seedlings, and increase soybean yield and quality.

[0006] To achieve the above invention purpose, the present invention provides the following technical solutions:

[0007] A method for improving the adaptability of soybeans to saline-alkali land, comprising the following steps: before sowing, soak the seeds with a rare earth lanthanum-salicylic acid mixed solution; at the three trifoliate leaf stage of soybeans, spray brassinolide on the stems and leaves.

[0008] Preferably, in the rare earth lanthanum-salicylic acid mixed solution, the lanthanum nitrate is 0.1 - 0.3 mmol / L, and the salicylic acid is 0.25 - 1.0 mmol / L.

[0009] Preferably, the volume ratio of the rare earth lanthanum-salicylic acid mixed solution to soybeans is 5 - 7:1 for mixed seed soaking.

[0010] Preferably, the rare earth lanthanum-salicylic acid mixed solution is used to soak the seeds at room temperature for 6 - 10 h.

[0011] Preferably, after the seed soaking is completed, rinse with distilled water 2-3 times, and store or sow after drying back.

[0012] Preferably, the three trifoliate leaf stage of the soybean is when the number of plants with three trifoliate leaves among the soybean seedlings in the field reaches more than 50%.

[0013] Preferably, the brassinolide is a 0.0016% aqueous solution, and it is diluted with water 1000-1400 times and sprayed.

[0014] More preferably, spray until the soybean seedling leaves are wet but no water drops fall.

[0015] Preferably, the saline-alkali land is a light to medium saline-alkali land with a salt content of 0.10-0.45%.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention provides a method for improving the adaptability of soybeans to saline-alkali land. Before sowing, soak the seeds with rare earth lanthanum and salicylic acid to enhance the seed germination ability of soybeans in saline-alkali land, and improve the germination rate, germination potential and germination index; spray brassinolide at the three trifoliate leaf stage of soybeans to enhance the saline-alkali resistance of soybeans, enhance the activities of SOD, POD and CAT in soybean seedlings, and reduce the MDA content in soybean seedlings.

[0018] The present invention improves the adaptability of soybeans to saline-alkali land through pre-sowing seed soaking of soybeans and chemical control management at the three trifoliate leaf stage, maintains the normal growth of soybeans when planted in saline-alkali land, and ensures the yield and quality of soybeans. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 : Effects of brassinolide at different dilution multiples on the SOD activity of soybean seedlings;

[0020] Figure 2 : Effects of brassinolide at different dilution multiples on the POD activity of soybean seedlings;

[0021] Figure 3 : Effects of brassinolide at different dilution multiples on the CAT activity of soybean seedlings;

[0022] Figure 4 : Effects of brassinolide at different dilution multiples on the MDA content of soybean seedlings;

[0023] Figure 5 : Effects of different saline-alkali tolerance measures on the yield and quality of soybeans. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention provides a method for improving the adaptability of soybeans to saline-alkali land, comprising the following steps: before sowing, soaking the seeds with a rare earth lanthanum-salicylic acid mixture; at the three trifoliate leaf stage of soybeans, spraying brassinolide on the stems and leaves. The present invention can enhance the germination ability of soybean seeds when sown in saline-alkali land, improve the saline-alkali resistance of seedlings, and ensure the yield and quality of soybeans under saline-alkali stress conditions.

[0025] In the rare earth lanthanum-salicylic acid mixture preferably used in the present invention, lanthanum nitrate is 0.1 - 0.3 mmol / L, more preferably 0.2 mmol / L; salicylic acid is 0.25 - 1.0 mmol / L, more preferably 0.5 mmol / L. Rare earth lanthanum can reduce the cell membrane permeability of plants, induce the stress resistance of soybean seeds, and improve the physiological activity level of soybean seeds; salicylic acid can adjust the hormone balance during the germination of soybean seeds, control the growth and development direction, and improve the stress resistance ability. By combining rare earth lanthanum and salicylic acid for seed soaking in the present invention, the saline-alkali stress resistance ability of soybean seeds can be enhanced, and the germination rate, germination potential, and seed germination index can be improved.

[0026] In the present invention, preferably during seed soaking, the volume ratio of the rare earth lanthanum-salicylic acid mixture to soybeans is 5 - 7:1, more preferably 6:1. The preferred seed soaking process is soaking at room temperature for 6 - 10 h, more preferably 8 h, and the room temperature is 23 - 25 °C.

[0027] In the present invention, preferably after seed soaking, rinse with distilled water 2 - 3 times, and store or sow after drying back. As an implementable way, dry back the seeds in a cool, ventilated, and dry environment.

[0028] In the present invention, preferably when the number of plants with three trifoliate leaves of field soybean seedlings reaches more than 50%, spray brassinolide. Brassinolide belongs to a plant growth regulator and is a sterol compound, which has the dual effects of promoting plant cell division and elongation, can promote well-developed roots, enhance photosynthesis, and improve the stress resistance of crops. In view of the saline-alkali stress conditions, spraying brassinolide at the three trifoliate leaf stage of soybeans in the present invention can promote the growth of seedlings, improve the activities of SOD, POD, and CAT of seedlings, reduce the MDA content, and improve the saline-alkali stress resistance ability of plants.

[0029] In the present invention, preferably the brassinolide is a 0.0016% aqueous solution, diluted 1000 - 1400 times with water for spraying, more preferably diluted 1200 times with water for spraying; more preferably spray until the soybean seedling leaves are wet but there is no water dripping.

[0030] In the present invention, preferably the saline-alkali land is light to medium saline-alkali land, and the salt content is 0.10 - 0.45%.

[0031] Unless otherwise specified, the methods used in the present invention are conventional methods, and the materials and reagents used can be obtained through commercial channels.

[0032] The technical solutions provided by the present invention will be described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention. Embodiment

[0033] A method for improving the adaptability of soybeans to saline-alkali land comprises the following steps:

[0034] Prepare a rare earth lanthanum-salicylic acid mixed solution: lanthanum nitrate 0.2 mmol / L, salicylic acid 0.5 mmol / L;

[0035] Seed soaking: Clean the soybean seeds, put them into a container, add 6 times the volume of the rare earth lanthanum-salicylic acid mixed solution to the solvent, and soak at room temperature for 8 h;

[0036] Drying back: Take out the seeds and dry them in a cool, ventilated and dry place;

[0037] Sowing: Sow the soybean seeds in the saline-alkali land;

[0038] Spray brassinolide: When more than 50% of the soybean seedlings in the field have three compound leaves, spray a 1200-fold solution of 0.0016% brassinolide aqueous solution until the leaves of the soybean seedlings are wet but there is no dripping water. Embodiment

[0039] A method for improving the adaptability of soybeans to saline-alkali land comprises the following steps:

[0040] (1) Prepare a rare earth lanthanum-salicylic acid mixed solution: lanthanum nitrate 0.1 mmol / L, salicylic acid 1.0 mmol / L;

[0041] (2) Seed soaking: Clean the soybean seeds, put them into a container, add 5 times the volume of the rare earth lanthanum-salicylic acid mixed solution to the solvent, and soak at room temperature for 10 h;

[0042] (3) Drying back: Take out the seeds and dry them in a cool, ventilated and dry place;

[0043] (4) Sowing: Sow the soybean seeds in the saline-alkali land;

[0044] (5) Spray brassinolide: When more than 50% of the soybean seedlings in the field have three compound leaves, spray a 1000-fold solution of 0.0016% brassinolide aqueous solution until the leaves of the soybean seedlings are wet but there is no dripping water. Embodiment

[0045] A method for improving the adaptability of soybeans to saline-alkali land comprises the following steps:

[0046] (1) Prepare a rare earth lanthanum-salicylic acid mixed solution: lanthanum nitrate 0.3 mmol / L, salicylic acid 0.25 mmol / L;

[0047] (2) Seed soaking: Clean the soybean seeds, put them into a container, add a rare earth lanthanum-salicylic acid mixture with a volume 7 times that of the solvent, and soak at room temperature for 6 h;

[0048] (3) Drying back: Take out the seeds and dry them in a cool, ventilated and dry place;

[0049] (4) Sowing: Sow the soybean seeds in saline-alkali land;

[0050] (5) Spraying brassinolide: When more than 50% of the soybean seedlings in the field have three compound leaves, spray a 1400-fold solution of 0.0016% brassinolide aqueous solution until the leaves of the soybean seedlings are wet but no water drops fall. Example

[0051] A soybean seed germination test was carried out at the Soybean Research Institute of Heilongjiang Academy of Agricultural Sciences to study the effects of different seed soaking treatments on the germination rate and germination potential of soybean seeds under saline-alkali stress.

[0052] Test materials

[0053] 99.9% lanthanum nitrate, purchased from the market; 99.9% salicylic acid raw powder, purchased from the market; clear water.

[0054] Test varieties

[0055] The soybean variety 'Heinong 531' was provided by the Soybean Research Institute of Heilongjiang Academy of Agricultural Sciences.

[0056] Test design

[0057] Set 4 seed soaking treatments, namely: (1) Seed soaking with clear water; (2) Seed soaking with 0.2 mmol / L lanthanum nitrate solution; (3) Seed soaking with 0.5 mmol / L salicylic acid solution; (4) Seed soaking with a mixture of 0.2 mmol / L lanthanum nitrate + 0.5 mmol / L salicylic acid. 40 seeds were used for each treatment, and repeated 3 times.

[0058] Clean the soybean seeds, and soak them with the solvents of (1)-(4) respectively. The ratio of soaking solution to seeds (V / V) = 6:1, soak at room temperature for 8 h. After soaking, dry them in a cool, ventilated and dry place. Another control treatment was set without seed soaking. Transfer the dried seeds and control seeds to a petri dish lined with gauze, with 40 seeds in each petri dish, evenly arranged, and add 30 mL of 100 mmol / L NaCl salt stress solution at the same time. Cultivate in an environment of 20°C / 25°C (11 h darkness / 13 h daytime), and replenish water in time after water evaporation to maintain the salt concentration. The germination potential was counted on the 3rd day; after 6 days, the germination was basically completed, and the germination rate was counted.

[0059] 4. Test results

[0060] Table 1 Effects of Different Seed Soaking Treatments on the Germination of Soybean Seeds

[0061] Treatment Germination rate (%) Germination potential (%) Control 68.33 19.17 Water 78.33 21.67 Lanthanum nitrate 85.83 30.83 Salicylic acid 84.17 26.67 Lanthanum nitrate + Salicylic acid 95.00 35.83

[0062] As can be seen from Table 1, through seed soaking, the germination ability of soybeans can be significantly improved. Under saline-alkali stress, soaking seeds with lanthanum nitrate and salicylic acid can further enhance the saline-alkali resistance of soybean seeds, improve the seed germination rate and germination potential, and the combined seed soaking effect of lanthanum nitrate and salicylic acid is the best. Example

[0063] A soybean seedling cultivation experiment was carried out at the Soybean Research Institute of Heilongjiang Academy of Agricultural Sciences to study the effects of different dilution multiples of brassinolide on the growth of soybean seedlings under saline-alkali stress.

[0064] 1. Test materials

[0065] 0.0016% brassinolide aqueous solution, purchased from the market.

[0066] 2. Test varieties

[0067] Soybean variety 'Heinong 531', provided by the Soybean Research Institute of Heilongjiang Academy of Agricultural Sciences.

[0068] 3. Test design

[0069] Three spraying concentrations were set, namely (1) diluted 1400 times; (2) diluted 1200 times; (3) diluted 1000 times. There were 50 seedlings in each treatment, with 3 replicates.

[0070] Soybean seeds were sown. After two true leaves grew, they were transplanted into 1 / 2 Hoagland solution for cultivation at room temperature of 25°C and light intensity of 3500 Lx. When the soybean seedlings grew to the three-compound-leaf stage, they were transplanted into 1 / 2 Hoagland solution supplemented with 150 mmol / L NaCl, and different dilution concentrations of brassinolide aqueous solution were sprayed respectively; at the same time, a control treatment (without spraying brassinolide) was set. After 7 days, the plant heights of 10 randomly selected seedlings were measured, and the third compound leaves were collected for physiological index determination.

[0071] Physiological index determination:

[0072] The SOD activity was determined by the nitroblue tetrazolium (NBT) method, and 50% inhibition of the NBT photoreaction was defined as one enzyme unit (U); the POD activity was determined by the guaiacol method; the CAT activity was determined by the potassium permanganate titration method; the MDA content was determined by the thiobarbituric acid method.

[0073] 4. Test results

[0074] Table 2 Effects of Different Dilution Multiples of Brassinolide on the Plant Heights of Soybean Seedlings

[0075] Treatment Control 1400 times 1200 times 1000 times Plant height (cm) 18.72 20.33 21.67 21.52

[0076] According to Table 2 and Figure 1 - 4 It can be seen that spraying brassinolide can increase the plant height of soybean seedlings, enhance the activities of SOD, POD and CAT in soybean seedling plants, reduce the MDA content, and improve the ability of soybean seedlings to resist saline-alkali stress. The best effect is achieved with a 1200-fold dilution. Example

[0077] A soybean planting experiment was conducted at the Anda experimental base of the Daqing Branch of the Heilongjiang Academy of Agricultural Sciences to study the effects of single and combined saline-alkali tolerance measures on the yield and quality of soybeans under saline-alkali stress.

[0078] Test materials

[0079] A mixed solution of 0.2 mmol / L lanthanum nitrate + 0.5 mmol / L salicylic acid; a 1200-fold dilution of 0.0016% brassinolide aqueous solution.

[0080] Test varieties

[0081] The soybean variety 'Heinong 531' was provided by the Soybean Research Institute of the Heilongjiang Academy of Agricultural Sciences.

[0082] Soil conditions of the test plot

[0083] The soybean planting field at the Anda experimental base of the Daqing Branch of the Heilongjiang Academy of Agricultural Sciences has a soil type of saline-alkali soil, pH 8.6, and a salt content of 0.32%.

[0084] Test design

[0085] The test adopted a randomized block design with 3 replicates. A total of 3 treatments were set, namely (1) seed soaking treatment with a mixed solution of 0.2 mmol / L lanthanum nitrate + 0.5 mmol / L salicylic acid; (2) spraying and chemical control treatment with a 1200-fold dilution of 0.0016% brassinolide aqueous solution at the three trifoliate stage of soybeans; (3) seed soaking treatment with a mixed solution of 0.2 mmol / L lanthanum nitrate + 0.5 mmol / L salicylic acid, and spraying and chemical control treatment with a 1200-fold dilution of 0.0016% brassinolide aqueous solution at the three trifoliate stage of soybeans; Another control treatment was set without taking saline-alkali tolerance measures. Each plot has 8 rows, the row length is 4.0 m, the row spacing is 0.6 m, and the plot area is 19.2 m 2 。

[0086] The test was sown on May 1 and harvested on October 5. When the soybeans were mature, a 2 m × 1.2 m = 2.4 m 2 quadrat was measured for yield, and the yield was converted; 10 soybean plants were randomly selected to measure the crude fat and crude protein contents of soybean grains.

[0087] Determination of crude fat content: Soxhlet extraction method; determination of crude protein content: Kjeldahl method.

[0088] 5. Test results

[0089] Table 3 Effects of different salinity-alkalinity tolerance measures on soybean yield and quality

[0090] Treatment <![CDATA[Yield (kg / hm 2 ).]]> Crude protein content (%) Crude fat content (%) Control 2057.3 37.06 20.69 Seed soaking 2207.5 37.53 21.53 Chemical control 2248.5 38.01 20.98 Seed soaking + Chemical control 2482.9 38.10 21.77

[0091] According to Table 3 and Figure 5 It can be seen that by taking salinity-alkalinity tolerance measures, the adaptability of soybeans to saline-alkali land can be effectively improved, that is, the anti-saline-alkali stress ability of soybean plants is improved. By soaking seeds with lanthanum nitrate-salicylic acid and spraying brassinolide, the yield of soybeans grown under saline-alkali land conditions is ensured. Saline-alkali land has no obvious effect on soybean quality, but through seed soaking and chemical control treatment, the total crude fat content of soybeans can be increased to ensure soybean quality.

[0092] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for improving the adaptability of soybeans to saline-alkali land, characterized in that, Including the following steps: Before sowing, soak the seeds with a rare earth lanthanum-salicylic acid mixture; at the three trifoliate leaf stage of soybeans, spray brassinolide on the stems and leaves; In the rare earth lanthanum-salicylic acid mixture, lanthanum nitrate is 0.1 - 0.3 mmol / L, and salicylic acid is 0.25 - 1.0 mmol / L; The brassinolide is a 0.0016% aqueous solution, diluted 1000 - 1400 times with water and sprayed.

2. The method for improving the adaptability of soybeans to saline-alkali land according to claim 1, characterized in that, The volume ratio of the rare earth lanthanum-salicylic acid mixture to soybeans is 5 - 7:1 for seed soaking.

3. The method for improving the adaptability of soybeans to saline-alkali land according to claim 1, characterized in that, The rare earth lanthanum-salicylic acid mixture is used for soaking seeds at room temperature for 6 - 10 h.

4. The method for improving the adaptability of soybeans to saline-alkali land according to claim 1, characterized in that, After the seed soaking is completed, rinse with distilled water 2 - 3 times, dry and store or sow.

5. The method for improving the adaptability of soybeans to saline-alkali land according to claim 1, characterized in that, The three trifoliate leaf stage of soybeans means that the number of plants with three trifoliate leaves among the field soybean seedlings reaches more than 50%.

6. The method for improving the adaptability of soybeans to saline-alkali land according to claim 1, wherein Spray until the soybean seedling leaves are moist but no water drops fall.

7. The method for improving the adaptability of soybeans to saline-alkali land according to claim 1, characterized in that, The saline-alkali land is a light to medium saline-alkali land with a salt content of 0.10 - 0.45%.

Images