Preparation process and application of spraying agent for improving drought resistance of peanuts

Abstract

The invention relates to the technical field of peanut planting, in particular to a preparation process and application of a spraying agent for improving drought resistance of peanuts. The preparation process comprises the following steps: preparing water-retaining gel powder; preparing humic acid powder; preparing composite humic acid hydrogel powder; and preparing the spraying agent for improving the drought resistance of the peanuts. The xanthan gum and the guar gum are combined through the sodium polyphosphate to prepare the water-retaining gel powder with the sodium polyphosphate as a connection structure, so that the water-retaining gel powder keeps stable performance in a wide temperature range and a pH range, the water loss phenomenon is reduced under the drought condition, and the drought resistance of peanuts is improved; the melatonin and the calcium chloride are also added, can eliminate active oxygen in plants, maintain the stability of membrane functions and improve the photosynthetic efficiency of the plants, and have an adjusting function in the growth and development and stress response processes of the plants.

Description

Technical Field

[0001] The invention relates to the technical field of peanut planting, and in particular to a preparation process and application of a spraying agent for improving drought resistance of peanuts. Background Art

[0002] Peanuts are an important source of edible vegetable oil and vegetable protein in the world, and the planting areas are mainly distributed in semi-arid and subtropical regions. China's total peanut production ranks first in the world. Surveys have found that 70% of China's peanut production areas are affected by drought stress. The drought problem seriously restricts the further improvement of my country's peanut production level. The lack of water resources seriously affects the growth and development of plants, resulting in reduced production or even death. The average annual loss of peanut production caused by drought is more than 20%. In addition to reducing production, drought also affects the quality of peanuts and aggravates the pollution of aflatoxin. At this stage, drought has become the most important abiotic stress affecting my country's peanut production. Therefore, it is very necessary to carry out the research and development of peanut drought resistance regulation technology.

[0003] Existing sprays for improving plant drought resistance are not targeted at peanuts, so the drought resistance agents for different plants have unstable effects. Therefore, the present invention provides a preparation process and application of a spray for improving peanut drought resistance to solve the above problem. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention aims to provide a preparation process and application of a spraying agent for improving the drought resistance of peanuts.

[0005] A preparation process of a spray for improving drought resistance of peanuts, comprising the following steps:

[0006] S1: Preparation of water-retaining gel powder

[0007] Weighing xanthan gum powder and dissolving it in glacial acetic acid solution to obtain a xanthan gum solution, weighing guar gum powder and adding it to deionized water to obtain a guar gum solution, and adding the guar gum solution to obtain a mixed solution, adding the mixed solution to a sodium polyphosphate solution, and then adding an acrylic acid solution and N,N'-methylenebisacrylamide to react to obtain a water-retaining gel powder;

[0008] S2: Preparation of humic acid powder

[0009] Weigh the treated sewage sludge that does not contain heavy metals, add dilute hydrochloric acid, heat and stir for 1 hour, let stand and cool, filter and dry to obtain sludge, add the sludge to NaOH solution, shake, let stand and settle, collect the supernatant after cooling, centrifuge to obtain centrifuge, add hydrochloric acid to the centrifuge, let stand and filter, centrifuge, collect the precipitate and dry to obtain humic acid powder;

[0010] S3: Preparation of composite humic acid hydrogel powder

[0011] The crosslinking agent is dissolved in an acrylic acid solution to obtain a crosslinking agent acrylic acid solution, humic acid powder and water-retaining gel powder are weighed and dissolved together in deionized water, an initiator is added, and then the crosslinking agent acrylic acid solution is added, the temperature is increased, stirred, dried, and crushed to obtain a composite humic acid hydrogel powder;

[0012] S4: Preparation of sprays to improve drought resistance in peanuts

[0013] A spraying agent for improving drought resistance of peanuts is obtained by mixing 10-15 parts by mass of composite humic acid hydrogel powder, 30-40 parts by mass of 0.3wt% calcium chloride solution and 2-4 parts by mass of melatonin.

[0014] Furthermore, the preparation of the water-retaining gel powder in step S1 comprises the following steps:

[0015] S1.1: Weigh 0.2-0.4 parts by mass of xanthan gum powder and dissolve it in 10-12 parts by volume of 10% glacial acetic acid solution, seal it, and perform ultrasonic treatment for 3-5 minutes, then place it at 24-26°C and let it stand for 24-26 hours to obtain a xanthan gum solution;

[0016] S1.2: Weigh 0.1-0.3 parts by mass of guar gum powder and add it to 10-15 parts by volume of deionized water, then heat it to 70-80°C, and stir it at a speed of 60-80r / min for 10-15min to obtain a guar gum solution, and add it to the xanthan gum solution and stir it at a constant temperature of 70-80°C for 8-10h to obtain a mixed solution;

[0017] S1.3: Add the mixed solution to 0.5% sodium polyphosphate solution, stir electromagnetically at 60-80°C for 30-35 minutes, then add 6-10 parts by weight of acrylic acid solution and 1-2 parts by weight of N,N'-methylenebisacrylamide, stir for 10-15 minutes, then heat to 80-90°C, then add 2-3 parts by weight of ammonium persulfate, stir electromagnetically for 1-1.5 hours, then take out to obtain a paste, seal the paste under anaerobic conditions and heat it in a water bath to 60-65°C, react for 20-25 minutes, let it stand at room temperature 24°C for 12-13 hours, then dry it in a drying oven at 80-85°C for 5-6 hours to obtain a water-retaining gel powder.

[0018] Furthermore, the preparation of humic acid powder in step S2 comprises the following steps:

[0019] S2.1: Weigh 50-60 parts by weight of treated sewage sludge that does not contain heavy metals, add 0.6 mol / L dilute hydrochloric acid at a solid-liquid ratio of 1 g: (10-12) mL, heat to 60-65°C constant temperature water bath and stir for 1 hour, remove the supernatant after standing and cooling for 15-20 minutes, and filter the remaining part and dry it to obtain sludge;

[0020] S2.2: Add the sludge to the NaOH solution, stir thoroughly for 5-10 minutes, transfer to a conical flask, seal with plastic wrap, put into an air bath constant temperature oscillator and oscillate at 60-65℃ for 24-26 hours, then take out and let it settle for 5-6 hours, collect the supernatant after cooling, centrifuge at 3000-3200r / min for 15-20 minutes, take the liquid part and obtain the centrifuge;

[0021] S2.3: Add hydrochloric acid to the centrifuge solution to adjust the pH to 2-3, let it stand for 3-4 hours, then filter it, centrifuge it at 3000-3200 r / min for 15-20 minutes, collect the precipitate, dry it at 60-65°C to constant weight, and obtain humic acid powder.

[0022] Furthermore, step S3 of preparing the composite humic acid hydrogel powder comprises the following steps:

[0023] S3.1: dissolving a crosslinking agent in an acrylic acid solution, and controlling the concentration of the crosslinking agent to be 0.3-0.5%, to obtain a crosslinking agent acrylic acid solution;

[0024] S3.2: Weigh 0.5-0.7 parts by mass of humic acid powder and 0.72-0.86 parts by mass of water-retaining gel powder and dissolve them together in 30-32 parts by mass of deionized water, stir magnetically for 5-10 minutes to fully dissolve them, stir and heat to 40-50°C, introduce nitrogen for 15-20 minutes, then add 0.6-1.2% of the total mass of the system as initiator, then add 6-8 parts by mass of cross-linking agent acrylic acid solution, heat to 70-80°C, stir for 3-4 hours, then wash with deionized water 3 times, and then soak the product in deionized water to completely cover it for 24 hours, dry at 60-70°C, and crush to obtain composite humic acid hydrogel powder.

[0025] Furthermore, the volume ratio of the guar gum solution to the xanthan gum solution is 1:(2-3).

[0026] Furthermore, the volume ratio of the mixed solution to the sodium polyphosphate solution is 1:(10-13).

[0027] Furthermore, the solid-liquid ratio of the sludge to the NaOH solution is 1 g: (10-12) mL.

[0028] Furthermore, the initiator is potassium persulfate, and the cross-linking agent is polyethylene glycol diacrylate or N,N'-methylenebisacrylamide.

[0029] A spraying agent for improving drought resistance of peanuts is prepared by the preparation process of the spraying agent for improving drought resistance of peanuts.

[0030] The invention discloses an application of a spraying agent for improving drought resistance of peanuts, wherein the spraying agent is prepared by the preparation process of the spraying agent for improving drought resistance of peanuts and is applied in spraying peanuts.

[0031] Compared with the prior art, the present invention has at least the following beneficial effects:

[0032] 1. The present invention combines xanthan gum and guar gum by sodium polyphosphate to prepare a water-retaining gel powder with sodium polyphosphate as a connecting structure. Both xanthan gum and guar gum have good water absorption, and sodium polyphosphate can further promote the absorption of water molecules, so that the hydrogel can absorb more water and form a hydrogel with a higher water content. The presence of sodium polyphosphate helps to reduce water evaporation and water loss, and prolong the service life of the product, especially in a dry environment. The ability to retain moisture is particularly prominent. At the same time, sodium polyphosphate, as a linear polymer, can form ionic bonds or hydrogen bonds with hydroxyls on the molecular chains of xanthan gum and guar gum through its multiple phosphate groups, thereby increasing the crosslinking density and stability of the hydrogel. In addition, sodium polyphosphate also has a certain buffering capacity, which can adjust the pH value of the hydrogel to a certain extent, so that it can maintain stable performance in a wider temperature range and pH range, reduce water loss under drought conditions, and improve the drought resistance of peanuts.

[0033] 2. The present invention adds humic acid powder extracted from sludge to hydrogel to prepare composite humic acid hydrogel powder. By spraying the spray containing composite humic acid hydrogel powder on the peanut leaves, the plants can directly absorb nutrients in the humic acid through the leaves, bypassing the limitation of root absorption, and transporting nutrients to the required parts faster. In addition, humic acid can chelate trace elements such as iron, zinc, manganese, etc., making them easier to be absorbed by plants, quickly alleviating deficiency symptoms, and maintaining the healthy state of leaves, which is beneficial to improving plant photosynthesis. Under drought conditions, the composite humic acid powder in the form of hydrogel is less volatile than humic acid directly dissolved in an aqueous solution, has a more stable form, and exists for a longer time. It can more stably and durably regulate the plant's absorption of water and nutrients, thereby improving the drought resistance of peanuts.

[0034] 3. The present invention also adds melatonin and calcium chloride. Melatonin is a class of small molecule indole compounds that can eliminate active oxygen in plants, maintain the stability of membrane function, and improve the photosynthetic efficiency of plants. It has multiple regulatory functions in plant growth and development processes such as vegetative growth, seed germination, rooting and flowering, and in response to adversity. Calcium chloride is a medium-element foliar fertilizer that is easy to prepare, easy to operate, and has no pollution to the environment. It can supplement calcium for plants, achieve a balanced nutrient supply, and improve the stress resistance of peanuts. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable those skilled in the relevant art to make and use the present disclosure.

[0036] Figure 1 The present invention is a flow chart of the preparation process of a spraying agent for improving drought resistance of peanuts used in an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The preparation process and application of a spraying agent for improving drought resistance of peanuts provided by the present invention are described in detail below in conjunction with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0038] Embodiment 1:

[0039] A preparation process of a spray for improving drought resistance of peanuts, such as Figure 1 As shown, the following steps are included:

[0040] S1: Preparation of water-retaining gel powder

[0041] S1.1: Weigh 0.2 parts by mass of xanthan gum powder and dissolve it in 10 parts by volume of 10% glacial acetic acid solution. After sealing, ultrasonicate for 3 minutes, and then place it at 24°C for 24 hours to obtain a xanthan gum solution;

[0042] S1.2: Weigh 0.1 parts by mass of guar gum powder and add it to 10 parts by volume of deionized water, then heat it to 70°C and stir it at a speed of 60 r / min for 10 min to obtain a guar gum solution, and add it to the xanthan gum solution and stir it at a constant temperature of 70°C for 8 h. The volume ratio of the guar gum solution to the xanthan gum solution is 1:2 to obtain a mixed solution;

[0043] S1.3: Add the mixed liquid into 0.5% sodium polyphosphate solution in a volume ratio of 1:10, stir electromagnetically at 60°C for 30 minutes, add 6 parts by mass of acrylic acid solution and 1 part by mass of N,N'-methylenebisacrylamide, stir for 10 minutes, raise the temperature to 80°C, add 2 parts by mass of ammonium persulfate, stir electromagnetically for 1 hour, and take out to obtain a paste. Seal the paste under anaerobic conditions and heat it to 60°C in a water bath. After reacting for 20 minutes, let it stand at room temperature 24°C for 12 hours, and then dry it in a drying oven at 80°C for 5 hours to obtain a water-retaining gel powder.

[0044] S2: Preparation of humic acid powder

[0045] S2.1: Weigh 50 parts by mass of treated sewage sludge that does not contain heavy metals, add 0.6 mol / L dilute hydrochloric acid at a solid-liquid ratio of 1 g:10 mL, heat to 60°C constant temperature water bath and stir for 1 hour, remove the supernatant after standing and cooling for 15 minutes, and filter the remaining part and dry it to obtain sludge;

[0046] S2.2: Add the sludge into the NaOH solution with a solid-liquid ratio of 1 g:10 mL. After stirring for 5 min, transfer to a conical flask, seal with plastic wrap, place in an air bath constant temperature oscillator and oscillate at 60 °C for 24 h. Then take out and let it settle for 5 h. After cooling, collect the supernatant, centrifuge at 3000 r / min for 15 min, take the liquid part and obtain the centrifuge liquid.

[0047] S2.3: Add hydrochloric acid to the centrifuge solution to adjust the pH to 2, let it stand for 3 hours, then filter it, centrifuge it at 3000 r / min for 15 minutes, collect the precipitate, and dry it at 60°C to constant weight to obtain humic acid powder.

[0048] S3: Preparation of composite humic acid hydrogel powder

[0049] S3.1: dissolving the cross-linking agent polyethylene glycol diacrylate in the acrylic acid solution, and controlling the concentration of the cross-linking agent to be 0.3%, to obtain a cross-linking agent acrylic acid solution;

[0050] S3.2: Weigh 0.5 parts by mass of humic acid powder and 0.72 parts by mass of water-retaining gel powder and dissolve them together in 30 parts by mass of deionized water, stir magnetically for 5 minutes to fully dissolve them, stir and heat to 40°C, introduce nitrogen for 15 minutes, then add 0.6% of the total mass of the system as initiator potassium persulfate, then add 6 parts by mass of cross-linking agent acrylic acid solution, heat to 70°C, stir for 3 hours, then wash with deionized water 3 times, and then soak the product in deionized water to completely cover it for 24 hours, dry at 60°C, and crush to obtain composite humic acid hydrogel powder.

[0051] S4: Preparation of sprays to improve drought resistance in peanuts

[0052] A spray for improving drought resistance of peanuts is obtained by mixing 10 parts by mass of composite humic acid hydrogel powder, 30 parts by mass of 0.3 wt% calcium chloride solution and 2 parts by mass of melatonin.

[0053] Embodiment 2:

[0054] A preparation process of a spray for improving drought resistance of peanuts, such as Figure 1 As shown, the following steps are included:

[0055] S1: Preparation of water-retaining gel powder

[0056] S1.1: Weigh 0.4 parts by mass of xanthan gum powder and dissolve it in 12 parts by volume of 10% glacial acetic acid solution. After sealing, ultrasonicate for 3 minutes, and then place it at 24°C for 24 hours to obtain a xanthan gum solution;

[0057] S1.2: Weigh 0.3 parts by mass of guar gum powder and add it to 15 parts by volume of deionized water, then heat it to 70°C and stir it at a speed of 60 r / min for 10 min to obtain a guar gum solution, and add it to the xanthan gum solution and stir it at a constant temperature of 70°C for 8 h. The volume ratio of the guar gum solution to the xanthan gum solution is 1:3 to obtain a mixed solution;

[0058] S1.3: Add the mixed liquid into 0.5% sodium polyphosphate solution in a volume ratio of 1:13, stir electromagnetically at 60°C for 30 minutes, add 10 parts by mass of acrylic acid solution and 2 parts by mass of N,N'-methylenebisacrylamide, stir for 10 minutes, raise the temperature to 80°C, add 3 parts by mass of ammonium persulfate, stir electromagnetically for 1 hour, and take out to obtain a paste. Seal the paste under anaerobic conditions and heat it to 60°C in a water bath. After reacting for 20 minutes, let it stand at room temperature 24°C for 12 hours, and then dry it in a drying oven at 80°C for 5 hours to obtain a water-retaining gel powder.

[0059] S2: Preparation of humic acid powder

[0060] S2.1: Weigh 60 parts by mass of treated sewage sludge that does not contain heavy metals, add 0.6 mol / L dilute hydrochloric acid at a solid-liquid ratio of 1 g:12 mL, heat to 60°C constant temperature water bath and stir for 1 hour, remove the supernatant after standing and cooling for 15 minutes, and filter the remaining part and dry it to obtain sludge;

[0061] S2.2: Add the sludge into the NaOH solution with a solid-liquid ratio of 1 g:12 mL. After stirring for 5 min, transfer to a conical flask, seal with plastic wrap, place in an air bath constant temperature oscillator and oscillate at 60 °C for 24 h. Then take out and let it settle for 5 h. After cooling, collect the supernatant, centrifuge at 3000 r / min for 15 min, take the liquid part and obtain the centrifuge liquid.

[0062] S2.3: Add hydrochloric acid to the centrifuge solution to adjust the pH to 2, let it stand for 3 hours, then filter it, centrifuge it at 3000 r / min for 15 minutes, collect the precipitate, and dry it at 60°C to constant weight to obtain humic acid powder.

[0063] S3: Preparation of composite humic acid hydrogel powder

[0064] S3.1: dissolving the cross-linking agent polyethylene glycol diacrylate in the acrylic acid solution, and controlling the concentration of the cross-linking agent to be 0.5%, to obtain a cross-linking agent acrylic acid solution;

[0065] S3.2: Weigh 0.7 parts by mass of humic acid powder and 0.86 parts by mass of water-retaining gel powder and dissolve them together in 30 parts by mass of deionized water, stir magnetically for 5 minutes to fully dissolve them, stir and heat to 40°C, introduce nitrogen for 15 minutes, then add 0.6% of the total mass of the system as initiator potassium persulfate, then add 6 parts by mass of cross-linking agent acrylic acid solution, heat to 70°C, stir for 3 hours, then wash with deionized water 3 times, and then soak the product in deionized water to completely cover it for 24 hours, dry at 60°C, and crush to obtain composite humic acid hydrogel powder.

[0066] S4: Preparation of sprays to improve drought resistance in peanuts

[0067] A spray for improving drought resistance of peanuts is obtained by mixing 15 parts by mass of composite humic acid hydrogel powder, 40 parts by mass of 0.3 wt% calcium chloride solution and 4 parts by mass of melatonin.

[0068] Embodiment 3:

[0069] A preparation process of a spray for improving drought resistance of peanuts, such as Figure 1 As shown, the following steps are included:

[0070] S1: Preparation of water-retaining gel powder

[0071] S1.1: Weigh 0.2 parts by mass of xanthan gum powder and dissolve it in 10 parts by volume of 10% glacial acetic acid solution. After sealing, ultrasonicate for 5 minutes, and then place it at 26°C for 26 hours to obtain a xanthan gum solution;

[0072] S1.2: Weigh 0.1 parts by mass of guar gum powder and add it to 10 parts by volume of deionized water, then heat it to 80°C and stir it at 80 r / min for 15 min to obtain a guar gum solution, and add it to the xanthan gum solution and stir it at 80°C for 10 h. The volume ratio of the guar gum solution to the xanthan gum solution is 1:2 to obtain a mixed solution;

[0073] S1.3: Add the mixed liquid into 0.5% sodium polyphosphate solution in a volume ratio of 1:10, stir electromagnetically at 80°C for 35 minutes, add 6 parts by mass of acrylic acid solution and 1 part by mass of N,N'-methylenebisacrylamide, stir for 15 minutes, raise the temperature to 90°C, add 2 parts by mass of ammonium persulfate, stir electromagnetically for 1.5 hours, and take out to obtain a paste. Seal the paste under anaerobic conditions and heat it to 65°C in a water bath. After reacting for 25 minutes, let it stand at room temperature 24°C for 13 hours, and then dry it in a drying oven at 85°C for 6 hours to obtain a water-retaining gel powder.

[0074] S2: Preparation of humic acid powder

[0075] S2.1: Weigh 50 parts by mass of treated sewage sludge that does not contain heavy metals, add 0.6 mol / L dilute hydrochloric acid at a solid-liquid ratio of 1 g:10 mL, heat to 65°C constant temperature water bath and stir for 1 hour, remove the supernatant after standing and cooling for 20 minutes, and filter the remaining part and dry it to obtain sludge;

[0076] S2.2: Add the sludge into the NaOH solution with a solid-liquid ratio of 1 g:10 mL. After stirring for 5 min, transfer to a conical flask, seal with plastic wrap, place in an air bath constant temperature oscillator and oscillate at 65 °C for 26 h. Then take out and let it settle for 6 h. After cooling, collect the supernatant, centrifuge at 3200 r / min for 20 min, take the liquid portion and obtain the centrifuge;

[0077] S2.3: Add hydrochloric acid to the centrifuge solution to adjust the pH to 3, let it stand for 4 hours, then filter it, centrifuge it at 3200 r / min for 20 minutes, collect the precipitate, dry it at 65°C to constant weight, and obtain humic acid powder.

[0078] S3: Preparation of composite humic acid hydrogel powder

[0079] S3.1: dissolving the cross-linking agent polyethylene glycol diacrylate in the acrylic acid solution, and controlling the concentration of the cross-linking agent to be 0.3%, to obtain a cross-linking agent acrylic acid solution;

[0080] S3.2: Weigh 0.5 parts by mass of humic acid powder and 0.72 parts by mass of water-retaining gel powder and dissolve them together in 30 parts by mass of deionized water, stir magnetically for 10 minutes to fully dissolve them, stir and heat to 50°C, introduce nitrogen for 20 minutes, then add 0.6% of the total mass of the system as initiator potassium persulfate, then add 6 parts by mass of cross-linking agent acrylic acid solution, heat to 80°C, stir for 4 hours, then wash with deionized water 3 times, and then soak the product in deionized water to completely cover it for 26 hours, dry at 70°C, and crush to obtain composite humic acid hydrogel powder.

[0081] S4: Preparation of sprays to improve drought resistance in peanuts

[0082] A spray for improving drought resistance of peanuts is obtained by mixing 10 parts by mass of composite humic acid hydrogel powder, 30 parts by mass of 0.3 wt% calcium chloride solution and 2 parts by mass of melatonin.

[0083] Embodiment 4:

[0084] A preparation process of a spray for improving drought resistance of peanuts, such as Figure 1 As shown, the following steps are included:

[0085] S1: Preparation of water-retaining gel powder

[0086] S1.1: Weigh 0.3 parts by mass of xanthan gum powder and dissolve it in 11 parts by volume of 10% glacial acetic acid solution. After sealing, ultrasonicate for 5 minutes, and then place it at 26°C for 26 hours to obtain a xanthan gum solution;

[0087] S1.2: Weigh 0.2 parts by mass of guar gum powder and add it to 12 parts by volume of deionized water, then heat it to 80°C and stir it at a speed of 80 r / min for 15 min to obtain a guar gum solution, and add it to the xanthan gum solution and stir it at a constant temperature of 80°C for 10 h. The volume ratio of the guar gum solution to the xanthan gum solution is 1:2 to obtain a mixed solution;

[0088] S1.3: Add the mixed liquid into 0.5% sodium polyphosphate solution in a volume ratio of 1:10, stir electromagnetically at 80°C for 35 minutes, add 8 parts by mass of acrylic acid solution and 1 part by mass of N,N'-methylenebisacrylamide, stir for 15 minutes, raise the temperature to 90°C, add 1.5 parts by mass of ammonium persulfate, stir electromagnetically for 1.5 hours, and then take out to obtain a paste. Seal the paste under anaerobic conditions and heat it to 65°C in a water bath. After reacting for 25 minutes, let it stand at room temperature 24°C for 13 hours, and then dry it in a drying oven at 85°C for 6 hours to obtain a water-retaining gel powder.

[0089] S2: Preparation of humic acid powder

[0090] S2.1: Weigh 55 parts by mass of treated sewage sludge that does not contain heavy metals, add 0.6 mol / L dilute hydrochloric acid at a solid-liquid ratio of 1 g:10 mL, heat to 65°C constant temperature water bath and stir for 1 hour, remove the supernatant after standing and cooling for 20 minutes, and filter the remaining part and dry it to obtain sludge;

[0091] S2.2: Add the sludge into the NaOH solution with a solid-liquid ratio of 1 g:10 mL. After stirring for 5 min, transfer to a conical flask, seal with plastic wrap, place in an air bath constant temperature oscillator and oscillate at 65 °C for 26 h. Then take out and let it settle for 6 h. After cooling, collect the supernatant, centrifuge at 3200 r / min for 20 min, take the liquid portion and obtain the centrifuge;

[0092] S2.3: Add hydrochloric acid to the centrifuge solution to adjust the pH to 3, let it stand for 4 hours, then filter it, centrifuge it at 3200 r / min for 20 minutes, collect the precipitate, dry it at 65°C to constant weight, and obtain humic acid powder.

[0093] S3: Preparation of composite humic acid hydrogel powder

[0094] S3.1: dissolving the cross-linking agent polyethylene glycol diacrylate in the acrylic acid solution, and controlling the concentration of the cross-linking agent to be 0.3%, to obtain a cross-linking agent acrylic acid solution;

[0095] S3.2: Weigh 0.6 parts by mass of humic acid powder and 0.84 parts by mass of water-retaining gel powder and dissolve them together in 30 parts by mass of deionized water, stir magnetically for 10 minutes to fully dissolve them, stir and heat to 50°C, introduce nitrogen for 20 minutes, then add 0.8% of the total mass of the system as initiator potassium persulfate, then add 7 parts by mass of cross-linking agent acrylic acid solution, heat to 80°C, stir for 4 hours, then wash with deionized water 3 times, and then soak the product in deionized water to completely cover it for 26 hours, dry at 70°C, and crush to obtain composite humic acid hydrogel powder.

[0096] S4: Preparation of sprays to improve drought resistance in peanuts

[0097] A spray for improving drought resistance of peanuts is obtained by mixing 12 parts by mass of composite humic acid hydrogel powder, 35 parts by mass of 0.3 wt% calcium chloride solution and 2 parts by mass of melatonin.

[0098] Comparative Example 1:

[0099] Compared with Example 1, Comparative Example 1 is a commercially available peanut drought-resistant spray.

[0100] Comparative Example 2:

[0101] Compared with Example 1, the difference of Comparative Example 2 is that no xanthan gum solution is added in step S1.2, specifically "S1.2: weigh 0.1 parts by mass of guar gum powder and add it to 10 parts by volume of deionized water, then heat to 70°C, and stir at a speed of 60 r / min for 10 minutes to obtain a mixed solution", and the prepared spraying agent for improving the drought resistance of peanuts is recorded as Comparative Example 2.

[0102] Comparative Example 3:

[0103] Compared with Example 1, the difference of Comparative Example 3 is that no guar gum solution is added in step S1.2, specifically "S1.2: heat the xanthan gum solution to 70°C and stir at a speed of 60 r / min for 10 minutes to obtain a mixed solution", and the prepared spraying agent for improving the drought resistance of peanuts is recorded as Comparative Example 3.

[0104] Comparative Example 4:

[0105] Compared with Example 1, the difference of Comparative Example 4 is that humic acid powder is not added in step S3.2, specifically: "S3.2: Weigh 0.72 parts by mass of water-retaining gel powder and dissolve it in 30 parts by mass of deionized water, stir it magnetically for 5 minutes to fully dissolve it, stir and heat it to 40°C, introduce nitrogen for 15 minutes, then add 0.6% of the total mass of the system as initiator potassium persulfate, then add 6 parts by mass of cross-linking agent acrylic acid solution, heat it to 70°C, stir for 3 hours, then wash it with deionized water 3 times, and then soak it in deionized water to completely cover the product for 24 hours, dry it at 60°C, and crush it to obtain a composite hydrogel powder". The prepared spray agent for improving the drought resistance of peanuts is recorded as Comparative Example 4.

[0106] During the flowering needle stage or pod-setting stage, the spray containing melatonin and calcium chloride was used for spraying until water dripped from the upper and lower surfaces of the leaves. The spray was applied once every 3 days for a total of 2 times. The effect of drought stress on the growth and development of peanuts was then observed, as shown in Table 1.

[0107] Table 1

[0108]

[0109] Table 2

[0110]

[0111] The main stem height, side branch length and root length of Examples 1-4 are greater than those of Comparative Examples 2-4, indicating that the peanuts of Examples have better growth potential, are less affected by drought, and have stronger drought resistance. The soluble sugar and abscisic acid contents in Examples 1-4 are higher, indicating that the metabolic activity of the peanuts of Examples is stronger, and the propanedione content is lower than that of Comparative Examples 2-4, indicating that the peanuts of Examples 1-4 have higher antioxidant activity.

[0112] The growth potential of peanuts in Comparative Example 1 is not as good as that in Example 1, indicating that the commercially available products are not as effective as the spray prepared by the present invention in improving the drought resistance of peanuts.

[0113] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A preparation process of a spray for improving drought resistance of peanuts, characterized in that: The steps include: S1: Preparation of water-retaining gel powder Weighing xanthan gum powder and dissolving it in glacial acetic acid solution to obtain a xanthan gum solution, weighing guar gum powder and adding it to deionized water to obtain a guar gum solution, and adding the guar gum solution to obtain a mixed solution, adding the mixed solution to a sodium polyphosphate solution, and then adding an acrylic acid solution and N,N'-methylenebisacrylamide to react to obtain a water-retaining gel powder; S2: Preparation of humic acid powder Weigh the treated sewage sludge that does not contain heavy metals, add dilute hydrochloric acid, heat and stir for 1 hour, let stand and cool, filter and dry to obtain sludge, add the sludge to NaOH solution, shake, let stand and settle, collect the supernatant after cooling, centrifuge to obtain centrifuge, add hydrochloric acid to the centrifuge, let stand and filter, centrifuge, collect the precipitate and dry to obtain humic acid powder; S3: Preparation of composite humic acid hydrogel powder The crosslinking agent is dissolved in an acrylic acid solution to obtain a crosslinking agent acrylic acid solution; the humic acid powder and the water-retaining gel powder are weighed and dissolved together in deionized water, an initiator is added, and then the crosslinking agent acrylic acid solution is added, the temperature is increased, stirred, dried, and crushed to obtain a composite humic acid hydrogel powder; S4: Preparation of sprays to improve drought resistance in peanuts A spraying agent for improving drought resistance of peanuts is obtained by mixing 20-30 parts by mass of composite humic acid hydrogel powder, 30-40 parts by mass of 0.3wt% calcium chloride solution and 2-4 parts by mass of melatonin.

2. The preparation process of a spray for improving drought resistance of peanut according to claim 1, characterized in that: The step S1 of preparing the water-retaining gel powder comprises the following steps: S1.1: Weigh 0.2-0.4 parts by mass of xanthan gum powder and dissolve it in 10-12 parts by volume of 10% glacial acetic acid solution, seal it, and perform ultrasonic treatment for 3-5 minutes, then place it at 24-26°C and let it stand for 24-26 hours to obtain a xanthan gum solution; S1.2: Weigh 0.1-0.3 parts by mass of guar gum powder and add it to 10-15 parts by volume of deionized water, then heat it to 70-80°C, and stir it at a speed of 60-80r / min for 10-15min to obtain a guar gum solution, and add it to the xanthan gum solution and stir it at a constant temperature of 70-80°C for 8-10h to obtain a mixed solution; S1.3: Add the mixed solution to 0.5% sodium polyphosphate solution, stir electromagnetically at 60-80°C for 30-35 minutes, then add 6-10 parts by weight of acrylic acid solution and 1-2 parts by weight of N,N'-methylenebisacrylamide, stir for 10-15 minutes, then heat to 80-90°C, then add 2-3 parts by weight of ammonium persulfate, stir electromagnetically for 1-1.5 hours, then take out to obtain a paste, seal the paste under anaerobic conditions and heat it in a water bath to 60-65°C, react for 20-25 minutes, let it stand at room temperature 24°C for 12-13 hours, then dry it in a drying oven at 80-85°C for 5-6 hours to obtain a water-retaining gel powder.

3. The preparation process of a spraying agent for improving drought resistance of peanut according to claim 2, characterized in that: The preparation of humic acid powder in step S2 comprises the following steps: S2.1: Weigh 50-60 parts by mass of treated sewage sludge that does not contain heavy metals, and calculate the solid-liquid ratio of 1g: Add 0.6 mol / L dilute hydrochloric acid in a ratio of (10-12) mL, heat to 60-65°C in a constant temperature water bath and stir for 1 hour, remove the supernatant after standing and cooling for 15-20 minutes, and filter the remaining part and dry it to obtain sludge; S2.2: Add the sludge to the NaOH solution, stir thoroughly for 5-10 minutes, transfer to a conical flask, seal with plastic wrap, put into an air bath constant temperature oscillator and oscillate at 60-65℃ for 24-26 hours, then take out and let it settle for 5-6 hours, collect the supernatant after cooling, centrifuge at 3000-3200r / min for 15-20 minutes, take the liquid part and obtain the centrifuge; S2.3: Add hydrochloric acid to the centrifuge solution to adjust the pH to 2-3, let it stand for 3-4 hours, then filter it, centrifuge it at 3000-3200 r / min for 15-20 minutes, collect the precipitate, dry it at 60-65°C to constant weight, and obtain humic acid powder.

4. The preparation process of a spray for improving drought resistance of peanut according to claim 3, characterized in that: Step S3 prepares composite humic acid hydrogel powder, comprising the following steps: S3.1: dissolving a crosslinking agent in an acrylic acid solution, and controlling the concentration of the crosslinking agent to be 0.3-0.5%, to obtain a crosslinking agent acrylic acid solution; S3.2: Weigh 0.5-0.7 parts by mass of humic acid powder and 0.72-0.86 parts by mass of water-retaining gel powder and dissolve them together in 30-32 parts by mass of deionized water, stir magnetically for 5-10 minutes to fully dissolve them, stir and heat to 40-50°C, introduce nitrogen for 15-20 minutes, then add 0.6-1.2% of the total mass of the system as initiator, then add 6-8 parts by mass of cross-linking agent acrylic acid solution, heat to 70-80°C, stir for 3-4 hours, then wash with deionized water 3 times, and then soak the product in deionized water to completely cover it for 24 hours, dry at 60-70°C, and crush to obtain composite humic acid hydrogel powder.

5. The preparation process of a spraying agent for improving drought resistance of peanut according to claim 2, characterized in that: The volume ratio of the guar gum solution to the xanthan gum solution is 1:(2-3).

6. The preparation process of a spraying agent for improving drought resistance of peanut according to claim 2, characterized in that: The volume ratio of the mixed solution to the sodium polyphosphate solution is 1:(10-13).

7. The preparation process of the spraying agent for improving drought resistance of peanut according to claim 3, characterized in that: The solid-liquid ratio of sludge to NaOH solution is 1g:(10-12)mL.

8. The preparation process of the spraying agent for improving drought resistance of peanut according to claim 4, characterized in that: The initiator is potassium persulfate, and the cross-linking agent is polyethylene glycol diacrylate or N,N'-methylenebisacrylamide.

9. A spray for improving drought resistance of peanuts, which is prepared by the preparation process of the spray for improving drought resistance of peanuts according to any one of claims 1 to 8.

10. Use of a spray for improving drought resistance of peanuts, wherein the spray is prepared by the preparation process of the spray for improving drought resistance of peanuts according to any one of claims 1 to 9 and is used in spraying peanuts.

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