Method for improving drought tolerance and yield of wheat through combined application of compost and sodium selenite

Abstract

The invention discloses a method for improving drought tolerance and yield of wheat through combined application of compost and sodium selenite, and belongs to the technical field of agricultural planting. According to the method, wheat is planted after compost is applied to soil, and when drought stress occurs, a sodium selenite solution is sprayed to wheat leaves, so that oxidative stress indexes such as MDA, H2O2 and O2 <-> of wheat can be remarkably reduced, and the activity of antioxidant enzymes such as SOD, POD, CAT and APX can be improved; physiological indexes such as chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, protein, soluble sugar and proline of wheat leaves are improved, growth and yield related traits of the wheat are improved, and finally the drought resistance and yield of the wheat are improved. The compost is prepared by taking 50%-55% of corn straw, 10%-20% of flue-cured tobacco straw, 20%-25% of rice straw, 10%-15% of livestock manure and 0.1%-1% of bacillus subtilis as raw materials, adding organic wastewater or tap water, mixing, composting and fermenting.

Description

Technical Field

[0001] The invention relates to a method for improving drought resistance and yield of wheat by combined application of compost and sodium selenite, and belongs to the field of agricultural technology planting. Background Art

[0002] Globally, wheat is one of the main food crops, and its yield and drought resistance are crucial to ensuring food security; especially in arid and semi-arid areas, wheat drought resistance and yield directly affect the sustainability of agricultural production; therefore, developing effective technical means to improve wheat growth performance and yield under drought is an important task in agricultural scientific research and practice.

[0003] At present, the main methods to improve wheat drought resistance and yield are to breed wheat varieties with stronger drought resistance, increase soil water retention capacity through tillage and soil improvement, improve irrigation systems to improve water use efficiency, and rationally apply fertilizers to improve wheat quality. However, these methods have limited application effects under drought conditions, especially in areas with limited water resources. Therefore, finding new and effective methods to improve wheat drought resistance and yield is a hot topic in current agricultural research.

[0004] Compost is an organic fertilizer that uses widely existing microorganisms in nature or artificially added fermentation bacteria to convert degradable organic matter in solid waste into stable humus through a controlled biochemical process; compost, as an organic fertilizer, is rich in nutrients; sodium selenite, as a selenium fertilizer, can not only increase the selenium content of wheat, but also enhance the stress resistance of wheat; although compost and sodium selenite each have certain effects, the effect of their combined application on wheat drought resistance and yield has not been fully studied and applied; the patent of this invention focuses on exploring a new method to improve wheat drought resistance and yield through the combined application of compost and sodium selenite, so as to meet the challenges of wheat production in fully arid and semi-arid areas. Summary of the invention

[0005] The purpose of the present invention is to provide a method for improving the drought resistance and yield of wheat by combining compost and sodium selenite, so as to solve the problems existing in the above-mentioned prior art.

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

[0007] One of the technical solutions of the present invention is to provide a method for preparing compost applicable to wheat planting, the steps comprising:

[0008] (1) After removing impurities from corn stalks, flue-cured tobacco stalks and rice stalks, crush them into 1 to 5 cm using a crusher and set aside.

[0009] (2) 50% to 55% corn stalks, 10% to 20% flue-cured tobacco stalks, 20% to 25% rice stalks, 10% to 15% livestock manure, and 0.1% to 1% Bacillus subtilis are fully mixed according to the mass percentage, and then organic wastewater or tap water is added to obtain a mixture with a moisture content of 60% to 70%, wherein the total mass percentage of corn stalks, flue-cured tobacco stalks, rice stalks, livestock manure and Bacillus subtilis is 100%.

[0010] (3) The mixture is subjected to a first fermentation to obtain a semi-finished product.

[0011] (4) The semi-finished product is fermented for the second time. After the fermentation is completed, the maturity of the fermentation product is tested. The fermentation product with better maturity is sieved with a sieve with a pore size of 10 mm to remove large particles and impurities. The finely divided part of the finished product is granulated with a granulator, and then dried with a dryer to obtain compost.

[0012] Furthermore, the livestock manure can be fresh pig manure, chicken manure or duck manure from a farm.

[0013] Furthermore, during the first fermentation, a loader is used to deliver the mixture into a primary fermentation tank and piled into a fermentation pile. A fan is used to force ventilation from the bottom of the fermentation tank to supply oxygen. After the mixture is coupled for 3 days, a pointer thermometer is used to begin measuring the temperature 25 to 30 cm below the surface of the compost. The reading is taken 5 to 10 minutes after insertion. The temperatures at five different positions are measured each time, and the temperature is maintained above 55° C. for 5 to 10 days.

[0014] Furthermore, during the second fermentation, the semi-finished product is piled into a 2-3 meter pile, and the pile is turned once a week. The fermentation time is 20-30 days.

[0015] The characteristics of well-decomposed compost are: the temperature naturally drops in the later stage and no longer rises, there is no odor but a scent of moist soil, there are white or grayish white mycelium attached to the pile, the granular structure is relatively loose, and the color is tan, brown or dark brown.

[0016] The second technical solution of the present invention provides an application of improving the drought resistance of wheat by combining compost and sodium selenite, the steps comprising: applying the prepared compost into the soil before planting and then sowing wheat, and spraying sodium selenite when drought stress occurs.

[0017] Furthermore, the compost is applied at a rate of 90 g to 120 g per kilogram of soil.

[0018] Furthermore, the concentration of the sodium selenite is 3-7 mg / L.

[0019] Compost was mixed into the soil before planting, and sodium selenite was sprayed on wheat leaves after drought occurred, with the spraying amount being until water naturally dripped from the wheat leaves.

[0020] Compost, as an organic fertilizer, is rich in nutrients, can promote the formation of soil solid structure in wheat fields, increase the soil's ability to retain water, heat, air and fertilizer, and is available for the growth of wheat under drought conditions. Sodium selenite, as a selenium fertilizer, can not only increase the selenium content of wheat, but also enhance the stress resistance of wheat. The combined application of the two in the present invention can effectively improve the drought resistance and yield of wheat.

[0021] Beneficial effects of the present invention:

[0022] The present invention analyzes the effects of combined application of compost and sodium selenite on wheat oxidative stress indexes, antioxidant enzyme activity, physiological indexes, growth indexes and yield under different degrees of drought stress. The results show that compared with the control group without compost and sodium selenite, the combined application of compost and sodium selenite showed significant reduction in wheat MDA, H2O2 and O2 under different drought stress levels. .- The accumulation of oxidative stress indicators such as sodium selenite increased the activities of SOD, POD, CAT and APX antioxidant enzymes in wheat, increased the contents of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, protein, soluble sugar and proline, significantly improved the growth indicators of wheat plant height, leaf length, leaf width and leaf area and yield-related traits, and ultimately increased wheat yield. It can be seen that the combined application of compost and sodium selenite can significantly improve wheat drought tolerance and yield. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is further described below by specific implementation methods. However, the following embodiments are only simple examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0024] All embodiments were carried out at the experimental base of Yunnan University located in Yuhua Street, Chenggong District, Kunming City, Yunnan Province, from October 16, 2023 to April 9, 2024.

[0025] Experiments not described in detail in the examples are all routine operations well known to those skilled in the art.

[0026] Example 1

[0027] Compost preparation

[0028] The preparation of compost specifically includes the following steps:

[0029] (1) After removing impurities from the crop straw raw materials, the corn straw is crushed into 3 cm, the tobacco straw is crushed into 3 cm, and the rice straw is crushed into 3 cm for later use.

[0030] (2) 52% corn stalks, 10% flue-cured tobacco stalks, 22% rice stalks, 15% fresh pig manure from a farm, and 1% Bacillus subtilis were mixed according to the mass percentage, and then organic wastewater was added and mixed evenly to obtain a mixture with a moisture content of 65%. The Bacillus subtilis was purchased from Xingtai Ai Shang Ke Hua Chong Horticultural Technology Co., Ltd., and the number of safe and effective live bacteria was ≥5.0×10 8 CFU / g.

[0031] (3) The mixed raw materials are transported into a primary fermentation tank by a loader and piled into a fermentation pile. A fan is used to force ventilation from the bottom of the fermentation tank upward to supply oxygen.

[0032] (4) After the mixture has been coupled for 3 days, a pointer thermometer is used to measure the temperature at 25 cm below the surface of the compost. The reading is taken 5 minutes after insertion. This is done at 10 a.m. every day. The temperature of five different locations is measured each time. The temperature is maintained above 55° C. for 8 days to obtain a semi-finished product.

[0033] (5) The semi-finished products are piled up to 2 meters for the second fermentation to prevent rainwater from flowing in. The piles are turned over once a week. The second fermentation time is 25 days. After the fermentation is completed, the maturity is tested. The fermented products with good maturity are as follows: the temperature naturally decreases in the later stage and no longer rises, there is no odor and the smell of moist soil, the fermented products have white or grayish white mycelium attached, the granular structure is relatively loose, and the color is tan, brown or dark brown.

[0034] (6) The fermented material with a good degree of maturity is screened with a sieve with a pore size of 10 mm to remove the large particles and impurities, leaving the finely divided part of the finished product for granulation, and then granulated with a granulator, and finally dried with a dryer to obtain compost.

[0035] Example 2

[0036] Pot experiment on improving drought tolerance and yield of wheat by using compost and sodium selenite

[0037] The soil used in this embodiment was taken from a farmland in Chenggong District, Kunming City, Yunnan Province, China (114.20′E, 30.28′N). First, soil samples with a depth of 0-20 cm were collected from multiple selected points. All soil samples were mixed together, screened through a 5 mm sieve and homogenized to prepare a composite soil sample for a potted experiment. Three subsamples were taken from the composite soil and their physicochemical properties were analyzed. The physicochemical properties of the soil were as follows: pH: 5.69, electrical conductivity (EC): 168.3 mS / m, organic matter: 21.4 g / kg, hydrolyzable nitrogen: 96.6 mg / kg, available phosphorus: 80.37 mg / kg, available potassium: 344.25 mg / kg, available boron: 0.92 mg / kg, exchangeable magnesium: 72.72 mg / kg, and chloride ion: 7.49 mg / kg.

[0038] In the experiment, each plastic pot (about 40 cm in diameter and 30 cm in depth) was filled with 10 kg of soil, and the local main wheat variety Yunmai 114 was used as the test variety. The test varieties were divided into 12 groups for planting, and the treatment method of each group is shown in Table 1; in all pots, the same amount of compound fertilizer with nitrogen, phosphorus and potassium components of 51% (17-17-17) effective nutrients was applied, and the dosage was 0.6 g / kg; the compound fertilizer and compost involved in each treatment of the potted plant experiment were added once before planting and not supplemented later; the spraying of sodium selenite involved in each treatment of the potted plant experiment was carried out 7 days after the drought occurred, and the spraying was carried out until the front and back of the leaves dripped naturally.

[0039] Table 1 shows the treatment methods of 12 different wheat groups

[0040]

[0041] Fifteen days after spraying sodium selenite, fresh leaves from the same part of wheat under different treatments (12 groups) were collected to measure the oxidative stress indicators of the leaves (MDA, H2O2 and O2 .- ), antioxidant enzyme activities (SOD, POD, CAT and APX) and physiological indicators (chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, protein, soluble sugar and proline); growth indicators such as plant height, leaf length, leaf width and leaf area were investigated during the jointing stage of wheat; and after the wheat was mature and harvested, the wheat ear yield, single plant yield, total grain number per plant, number of grains per ear and 1000-grain weight were investigated.

[0042] The test results of the pot test of compost and sodium selenite in this example in improving the drought resistance and yield of wheat are shown in Tables 2 to 6.

[0043] Table 2 Statistics of oxidative stress indicators in wheat leaves of each group

[0044] Group MDA (nmol / g) <![CDATA[H2O2(nmol / g)]]> <![CDATA[O2 ·- (nmol / g)]]> Group 1 22.39±0.14 15.9±0.02 0.31±0.01 Group 2 18.20±0.18 15.86±0.44 0.31±0.02 Group 3 14.75±0.23 15.26±0.51 0.31±0.01 Group 4 14.10±0.31 12.87±0.63 0.29±0.02 Group 5 23.61±0.67 18.17±0.44 0.31±0.02 Group 6 20.24±0.65 16.9±0.22 0.29±0.02 Group 7 20.13±0.41 15.81±0.51 0.29±0.02 Group 8 19.60±0.23 14.42±0.12 0.27±0.00 Group 9 38.87±0.98 21.35±0.04 0.35±0.01 Group 10 33.05±0.37 19.83±0.57 0.34±0.01 Group 11 30.90±0.30 19.19±0.48 0.33±0.01 Group 12 29.29±0.41 16.84±0.29 0.31±0.01

[0045] Table 3 Statistics of oxidative stress indicators in wheat leaves of each group

[0046] Group SOD(U / g) POD(U / g) CAT(U / g) APX(U / g) Group 1 1014.94±16.10 396.00±4.00 1483.13±12.80 10.05±0.03 Group 2 1112.95±18.54 605.67±2.52 1664.06±14.91 10.14±0.06 Group 3 1156.91±17.20 656.00±3.46 1768.54±38.80 10.61±0.13 Group 4 1237.69±31.42 751.33±2.31 2222.15±44.56 12.31±0.49 Group 5 989.09±4.31 559.33±5.13 1936.73±46.61 9.83±0.05 Group 6 1028.84±8.27 716.33±5.69 1985.15±19.15 10.57±0.22 Group 7 1076.80±13.47 735.33±5.03 2237.44±13.93 10.7±0.42 Group 8 1147.07±13.97 782.33±14.5 2515.21±12.13 11.35±0.32 Group 9 418.38±16.46 427.00±7.94 1671.71±39.23 11.3±0.28 Group 10 1040.79±34.11 490.67±18.15 1712.48±58.59 12.89±0.18 Group 11 1047.33±12.04 536.33±17.79 1962.22±55.37 13.71±0.10 Group 12 1097.50±32.12 640.00±5.00 2076.89±31.97 14.76±0.27

[0047] The results in Table 2 and Table 3 show that the combined application of compost and sodium selenite (Groups 4, 8 and 12) significantly reduced the MDA, H2O2 and O2 content of the leaves of the wheat variety "Yunmai 114" under different drought conditions. ·- The contents of oxidative stress indicators such as SOD, POD, CAT and APX were increased. Under normal watering conditions, the MDA, H2O2 and O2 content of the leaves of wheat variety "Yunmai 114" in group 4 were compared with those in group 1. ·- The contents of oxidative stress indicators such as oxidative stress decreased by 37.02%, 19.07% and 7.23%, and the activities of antioxidant enzymes such as SOD, POD, CAT and APX increased by 21.95%, 89.73%, 49.83% and 22.55%. Compared with the 5th group, the 8th group under moderate drought stress had a significant difference in MDA, H2O2 and O2 ·- The contents of oxidative stress indicators such as oxidative stress decreased by 16.99%, 20.61% and 11.65%, and the activities of antioxidant enzymes such as SOD, POD, CAT and APX increased by 15.97%, 39.87%, 29.87% and 15.50%. Compared with the 9th group, the 12th group under severe drought stress had a significant effect on the MDA, H2O2 and O2 content of the leaves of the wheat variety "Yunmai 114". ·- The contents of oxidative stress indicators such as SOD, POD, CAT and APX decreased by 24.65%, 21.15% and 9.89%, and the activities of antioxidant enzymes such as SOD, POD, CAT and APX increased by 162.32%, 49.88%, 24.24% and 30.58%.

[0048] Table 4 Statistics of physiological indexes of wheat leaves in each group

[0049]

[0050] The results in Table 4 show that the combined application of compost and sodium selenite (Group 4, Group 8 and Group 12) significantly increased the contents of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, protein, soluble sugar and proline in the leaves of wheat variety "Yunmai 114" under different drought conditions. Under normal watering conditions, the contents of chlorophyll a, chlorophyll b, total chlorophyll, protein, soluble sugar and proline in the leaves of wheat variety "Yunmai 114" in Group 4 increased by 30.52%, 22.46%, 18.39%, 8.01%, 65.58% and 254.00% respectively, except for carotenoids. Under moderate drought stress, the contents of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, protein, soluble sugar and proline in the leaves of wheat variety "Yunmai 114" in treatment group 8 increased by 31.78%, 30.95%, 19.36%, 48.01%, 20.27%, 95.40% and 14.54% respectively compared with those in treatment group 5. Under severe drought stress, the contents of chlorophyll b, total chlorophyll, carotenoids, protein, soluble sugar and proline in the leaves of wheat variety "Yunmai 114" in treatment group 12 increased by 34.92%, 26.92%, 73.00%, 69.04%, 139.21% and 3.84% respectively compared with those in treatment group 9 except chlorophyll a.

[0051] Table 5 Contents of wheat growth indicators in different treatment groups

[0052]

[0053] The results in Table 5 show that the combined application of compost and sodium selenite (Group 4, Group 8 and Group 12) significantly increased the plant height, leaf length, leaf width and leaf area of ​​the wheat variety "Yunmai 114" at the jointing stage under different drought conditions. Under normal watering conditions, the plant height, leaf length, leaf width and leaf area of ​​wheat in Group 4 increased by 15.63%, 23.73%, 11.45% and 14.25% respectively compared with Group 1. Under moderate drought stress, the plant height, leaf length, leaf width and leaf area of ​​wheat in Group 8 increased by 5.58%, 11.94%, 19.89% and 21.58% respectively compared with Group 5. Under severe drought stress, the plant height, leaf length, leaf width and leaf area of ​​wheat in Group 12 increased by 5.45%, 12.56%, 7.65% and 13.82% respectively compared with Group 9.

[0054] Table 6 Statistics of wheat yield and yield traits in each group

[0055] Group Single ear yield (g) Yield per plant (g) Total number of seeds per plant Number of grains per ear Thousand-grain weight (g) Group 1 <![CDATA[1.58±0.02 f ]]> <![CDATA[9.45±0.30 de ]]> <![CDATA[177.60±5.57 h ]]> <![CDATA[33.16±0.86 j ]]> <![CDATA[47.30±0.24 f-h ]]> Group 2 <![CDATA[1.84±0.05 d ]]> <![CDATA[9.55±0.05 de ]]> <![CDATA[184.73±4.83 g ]]> <![CDATA[35.95±0.67 h ]]> <![CDATA[50.42±0.46 c ]]> Group 3 <![CDATA[1.87±0.08 cd ]]> <![CDATA[10.85±0.09 c ]]> <![CDATA[204.20±0.80 e ]]> <![CDATA[36.13±0.21 h ]]> <![CDATA[50.84±0.42 c ]]> Group 4 <![CDATA[1.96±0.08 c ]]> <![CDATA[11.08±0.59 a-c ]]> <![CDATA[228.00±2.09 c ]]> <![CDATA[36.56±0.07 h ]]> <![CDATA[52.88±0.85 b ]]> Group 5 <![CDATA[1.56±0.06 fg ]]> <![CDATA[8.52±0.21 f ]]> <![CDATA[175.13±0.81 h ]]> <![CDATA[33.23±0.40 j ]]> <![CDATA[40.79±0.75 k <!-- 7 -->]]> Group 6 <![CDATA[1.62±0.08 ef ]]> <![CDATA[8.62±0.20 f ]]> <![CDATA[193.60±6.88 f ]]> <![CDATA[36.71±0.95 gh ]]> <![CDATA[44.00±0.65 j ]]> Group 7 <![CDATA[1.88±0.10 cd ]]> <![CDATA[9.29±0.01 de ]]> <![CDATA[195.33±4.57 f ]]> <![CDATA[37.55±0.49 fg ]]> <![CDATA[47.22±0.52 f-h ]]> Group 8 <![CDATA[1.94±0.06 od ]]> <![CDATA[9.72±0.06 d ]]> <![CDATA[229.67±2.93 c ]]> <![CDATA[41.83±0.25 c ]]> <![CDATA[48.55±0.63 e ]]> Group 9 <![CDATA[0.76±0.03 h ]]> <![CDATA[5.39±0.30 h ]]> <![CDATA[110.33±2.81 j ]]> <![CDATA[15.21±0.30 l ]]> <![CDATA[44.33±0.66 ij ]]> Group 10 <![CDATA[0.83±0.09 h ]]> <![CDATA[5.80±0.28 h ]]> <![CDATA[120.67±2.90 i ]]> <![CDATA[17.63±0.60 k ]]> <![CDATA[45.11±0.24 i ]]> Group 11 <![CDATA[1.46±0.05 g ]]> <![CDATA[7.97±0.28 g ]]> <![CDATA[180.47±4.41 gh ]]> <![CDATA[32.92±0.50 j ]]> <![CDATA[46.56±0.51 h ]]> Group 12 <![CDATA[1.72±0.05 e ]]> <![CDATA[11.21±0.17 a-c ]]> <![CDATA[240.27±2.72 b ]]> <![CDATA[38.15±0.49 ef ]]> <![CDATA[48.10±0.29 ef ]]>

[0056] The results in Table 6 show that the combined application of compost and sodium selenite (Group 4, Group 8 and Group 12) significantly increased the yield and yield-related traits of the wheat variety "Yunmai 114" under different drought conditions. Under normal watering conditions, compared with Group 1, the combined application of compost and sodium selenite significantly increased wheat yield and yield-related traits, among which Group 4 had the best effect, with single ear yield, single plant yield, total number of grains per plant, number of grains per ear and thousand-grain weight increasing by 24.05%, 17.25%, 28.38%, 10.25% and 11.80% respectively. Under moderate drought stress, compared with Group 5, the combined application of compost and sodium selenite significantly increased wheat yield and yield-related traits, with Group 8 having the best effect, where single ear yield, single plant yield, total number of grains per plant, number of grains per ear, and 1000-grain weight increased by 24.36%, 14.08%, 31.14%, 25.88%, and 19.02%, respectively. Under severe drought stress, compared with Group 9, the combined application of compost and sodium selenite significantly increased wheat yield and yield-related traits, with Group 12 having the best effect, where single ear yield, single plant yield, total number of grains per plant, number of grains per ear, and 1000-grain weight increased by 126.32%, 107.98%, 117.77%, 150.82%, and 8.50%, respectively. In summary, the test results show that drought stress has an inhibitory effect on various growth indicators, yield traits and yield of wheat. However, the combined treatment of compost and sodium selenite can significantly improve drought tolerance under different degrees of drought stress conditions and promote the growth and yield of wheat. Among various treatments, the combined application of compost and sodium selenite can effectively reduce the negative impact of drought stress on wheat.

Claims

1. A method for improving drought tolerance and yield of wheat by combining compost and sodium selenite, characterized in that: Apply compost to the soil before sowing wheat. When drought occurs, spray sodium selenite solution.

2. The method for improving drought resistance and yield of wheat by combining compost and sodium selenite according to claim 1, characterized in that: The preparation method of the compost is as follows: (1) 50% to 55% corn stalks, 10% to 20% flue-cured tobacco stalks, 20% to 25% rice stalks, 10% to 15% livestock manure, and 0.1% to 1% Bacillus subtilis are fully mixed according to the mass percentage, and then organic wastewater or tap water is added to obtain a mixture with a moisture content of 60% to 70%, wherein the total mass percentage of corn stalks, flue-cured tobacco stalks, rice stalks, livestock manure, and Bacillus subtilis is 100%; (2) subjecting the mixture to a first fermentation to obtain a semi-finished product; (3) The semi-finished product is subjected to a second fermentation. After the fermentation is completed, it is granulated and dried to obtain compost.

3. The method for improving drought resistance and yield of wheat by combining compost and sodium selenite according to claim 2, characterized in that: The first fermentation in step (2) is carried out at a temperature above 55° C. for 5 to 10 days.

4. The method for improving drought resistance and yield of wheat by combining compost and sodium selenite according to claim 2, characterized in that: The second fermentation in step (3) is carried out at 55° C. for 20 to 30 days.

5. The method for improving drought tolerance and yield of wheat by combining compost and sodium selenite as claimed in claim 1, characterized in that: The compost is applied at a rate of 90 g to 120 g per kilogram of soil.

6. The method for improving drought tolerance and yield of wheat by combining compost and sodium selenite as claimed in claim 1, characterized in that: The concentration of the sodium selenite is 3-7 mg / L, and the sodium selenite is sprayed on the front and back sides of wheat leaves to drip naturally.

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