CN104396983B - The one low temperature resistant protection membrane of planting fruit-trees and preparation method - Google Patents

Abstract

A low temperature resistant protective film agent for fruit trees and its preparation method, the main components of which are vinyl acetate, soft monomer-butyl acrylate, hard monomer-methyl methacrylate, functional group monomer-acrylic acid and emulsifying synergist Copolymer emulsion. The obtained copolymer emulsion is added with functional materials such as inorganic dispersant, organic dispersant, wetting agent, film-forming agent, surfactant, antifreeze, heat-resistant material, bactericide and colloid. The preparation process of the present invention is simple, the cost is low, the polymerization of the copolymerized emulsion is stable, there is no gel, the minimum film-forming temperature is 0°C, the film-forming effect is good, the solid content is 44.5%, and the water absorption is 19.66%. Sunburn and strip damage, delayed germination, safety and environmental protection.

Description

A low temperature resistant protective film agent for fruit trees and its preparation method

technical field

The invention belongs to the field of plant protection, and in particular relates to a protective film agent applied on the surface of fruit trees in the dormant period to protect fruit tree branches from low temperature damage and improve the ability of fruit trees to cope with low temperature stress.

Background technique

In the cold and cold climate conditions in the north, the frequency of low temperature damage to plants is high and the impact is extensive. With the deterioration of the ecological environment, this damage is becoming more and more serious. Nowadays, low temperature damage has become one of the important meteorological disasters that restrict the cultivation of fruit trees and affect the yield and quality of fruits.

A drop in temperature often leads to an increase in the permeability of plant cell membranes, and the leakage of substances in the membranes, resulting in physiological drought and the accumulation of toxic substances. Low temperature stress triggers and intensifies plant cell membrane peroxidation, damages the cell membrane system (including damage to membrane structure and membrane function), and severe membrane peroxidation leads to cell death.

The extreme low temperature in winter and the sudden temperature change between winter and spring are the main environmental factors that cause low temperature damage to fruit trees. In winter and spring, direct sunlight on the surface of the trunk can easily cause tissue dehydration and burns and death; young flower buds are vulnerable to continuous low temperature damage.

Although the existing commercially available protective film agents for fruit trees have some effects on the sunburn damage of fruit tree branches, the coating film is easy to fall off due to more autumn rain in cold and cool climate areas. In winter and spring, the temperature difference between the south and the southwest of the tree body changes drastically between day and night, and it is very easy to produce alternating freeze-thaw and sunburn of the branches and trunks, causing a large number of rot diseases, and dead branches and trees are often seen. Therefore, under such climatic conditions, there is an urgent need for a protective film agent that is breathable, water-retaining, heat-resistant, anti-freezing, and rain-proof, so as to suppress the saplings in arid areas and prevent the occurrence of rot caused by sunburn in branches and trunks under cold and cool climate conditions.

Contents of the invention

The purpose of the present invention is to provide a protective film agent for fruit trees with thermal insulation, adsorption, ventilation, water retention, good durability, and non-toxicity. It is aimed at practical problems such as overwintering of fruit tree saplings, freezing damage of top flower buds, and sunburn of branches. Protect fruit trees from overwintering safely, reduce economic losses caused by low temperature in production, and improve planting efficiency.

The low temperature resistant protective film agent provided by the present invention is mainly composed of: vinyl acetate, soft monomer - butyl acrylate, hard monomer - methyl methacrylate, functional group monomer - acrylic acid and emulsifying synergist prepared into a copolymer lotion.

The obtained copolymer emulsion is added with other functional materials: inorganic dispersant—sodium hexametaphosphate, organic dispersant—sodium polyacrylate, wetting agent—{2-amino-2-methyl-1-propanol (AMP-95) }, Film-forming agent - dodecyl alcohol ester, surfactant - polypropylene glycol, antifreeze - ethylene glycol, heat-resistant material - far-infrared ceramic powder, fungicide - thiophanate-methyl, colloid - hydroxyethyl Cellulose, coloring material—titanium dioxide, and the rest are water.

The mass percentage of copolymer emulsion components is: sodium sulfite 0.01%-0.15%, ammonium persulfate 0.07%-0.28%, polyvinyl alcohol 0.45%-0.63%, sodium dodecyl sulfate (SDS) 1.28%-1.8%, non-ionic Type of alkylphenol polyoxyethylene ether (OP-10) 2.57%-3.61%, vinyl acetate 25%-30%, butyl acrylate 15%-20%, methyl methacrylate 1%-5%, acrylic acid 0.5%-1%, a small amount of sodium bicarbonate (to adjust the pH value), the balance is water, and the total amount is 100%.

The mass percentage of each component in the low temperature protective film for fruit trees is: sodium hexametaphosphate 0.3%-0.7%, sodium polyacrylate 0.5%-1%, 2-amino-2-methyl-1-propanol (AMP-95) 0.2%-0.3%, lauryl alcohol ester 0.8%-1%, polypropylene glycol 0.1%-0.4%, ethylene glycol 2.5%-2.8%, far-infrared ceramic powder 2%-6%, thiophanate-methyl 0.08%-0.1%, titanium dioxide 10%-15%, hydroxyethyl cellulose 0.3%-0.5%, copolymer emulsion 30%-40%, the balance is water, the total is 100%.

Copolymer emulsion preparation method: Dissolve 0.01%-0.15% sodium sulfite and 0.07%-0.28% ammonium persulfate in 10%-12% water according to the mass ratio to make a mixed solution of sodium sulfite and ammonium persulfate.

Add 15%-20% water to the reactor first, then gradually add and dissolve 0.45%-0.63% polyvinyl alcohol, 1.28%-1.8% sodium lauryl sulfate, 2.57%-3.61% OP-10 and 5.53%-29.12% water, dissolve and filter out impurities repeatedly, and control the temperature of the water bath at 30±2°C. Then dropwise add a mixture of vinyl acetate, butyl acrylate, methyl methacrylate and acrylic acid, the mixture consists of 25%-30% vinyl acetate, 15%-20% butyl acrylate, 1%-5% It is composed of methyl methacrylate and 0.5%-1% acrylic acid. After fully emulsified, add one-third of the sodium sulfite and ammonium persulfate solution dropwise, adjust the pH value to 6-7 with sodium bicarbonate, add the remaining sodium sulfite and ammonium persulfate solution dropwise after a period of constant temperature, keep warm for 2 hours and cool down before discharging That is the copolymer emulsion.

Preparation of protective film agent: 0.3%-0.7% sodium hexametaphosphate, 0.5%-1% sodium polyacrylate, 0.2%-0.3% 2-amino-2-methyl-1-propanol ( AMP-95), 0.8%-1% dodecyl alcohol ester, 0.1%-0.4% polypropylene glycol, 2.5%-2.8% ethylene glycol, 2%-6% far-infrared ceramic powder, 0.08%-0.1% formazan Mix thiophanate and 32.2%-53.22% water evenly, then add 10%-15% titanium dioxide and 0.3%-0.5% hydroxyethyl cellulose according to the mass ratio, and disperse into a homogenate at high speed; the homogenate is passed through 100 mesh After sieving and filtering, add 30%-40% copolymer emulsion dropwise, and stir evenly at low speed to form a protective film agent.

The positive effect of the present invention: the preparation process is simple, the cost is low, the copolymerization emulsion polymerization is stable, has no gel, pH6-7, the minimum film-forming temperature is 0°C, the film-forming effect is good, and the solid content (residue after the emulsion is dried under specified conditions) Part accounts for the mass percentage of the total) 44.5%, water absorption 19.66%, can significantly improve the ability of fruit trees to cope with low temperature freezing damage, prevent sunburn and stalk damage, delay germination, and is safe and environmentally friendly.

detailed description

Example 1

Preparation of copolymer emulsion: Dissolve 0.01% sodium sulfite and 0.07% ammonium persulfate in 10% water according to the mass ratio to prepare a mixed solution of sodium sulfite and ammonium persulfate.

First add 15% water to dissolve 0.45% polyvinyl alcohol in the reaction kettle according to the mass ratio, then add 1.28% sodium lauryl sulfate, 2.57% OP-10 and 29.12% water, dissolve and filter again Impurities, control the temperature of the water bath at 30±2°C, and then dropwise add a mixture of vinyl acetate, butyl acrylate, methyl methacrylate and acrylic acid, the mixture consists of 25% vinyl acetate, 15% butyl acrylate, 1% methyl methacrylate and 0.5% acrylic acid. After full emulsification, add one-third of the mixed solution of sodium sulfite and ammonium persulfate dropwise, adjust the pH value to 6-7 with sodium bicarbonate, and add the remaining mixed solution of sodium sulfite and ammonium persulfate dropwise after constant temperature for a period of time. Insulate for 2 hours, and discharge after cooling to obtain copolymer emulsion.

Preparation of protective film agent: 0.3% sodium hexametaphosphate, 0.5% sodium polyacrylate, 0.2% 2-amino-2-methyl-1-propanol (AMP-95), 0.8% dodeca Carbon alcohol ester, 0.1% polypropylene glycol, 2.5% ethylene glycol, 2% far-infrared ceramic powder, 0.08% thiophanate-methyl and 53.22% water are mixed evenly, and then 10% titanium dioxide, 0.3% Hydroxyethyl cellulose is dispersed into a homogenate at a high speed; the homogenate is filtered through a 100-mesh sieve and dripped into a 30% mass ratio copolymer emulsion, and stirred evenly at a low speed to obtain the fruit tree protective film agent of the present invention.

Example 2

Preparation of copolymer emulsion: Dissolve 0.08% sodium sulfite and 0.18% ammonium persulfate in 11% water according to the mass ratio to prepare a mixed solution of sodium sulfite and ammonium persulfate.

First add 17.5% water to dissolve 0.54% polyvinyl alcohol in the reaction kettle according to the mass ratio, then add 1.54% sodium lauryl sulfate, 3.09% OP-10 and 17.32% water, dissolve and filter again Impurities, control the temperature of the water bath at 30±2°C, then dropwise add a mixture of vinyl acetate, butyl acrylate, methyl methacrylate and acrylic acid, the mixture consists of 27.5% vinyl acetate, 17.5% butyl acrylate, 3% methyl methacrylate and 0.75% acrylic acid. After fully emulsified, add one-third of the mixed solution of sodium sulfite and ammonium persulfate dropwise, adjust the pH value to 6-7 with sodium bicarbonate, add the remaining mixed solution of sodium sulfite and ammonium persulfate dropwise after a period of constant temperature, keep warm for 2 hours, and cool The final output is the copolymer emulsion.

Preparation of protective film agent: 0.5% sodium hexametaphosphate, 0.75% sodium polyacrylate, 0.25% 2-amino-2-methyl-1-propanol (AMP-95), 0.9% dodecyl Carbon alcohol ester, 0.25% polypropylene glycol, 2.65% ethylene glycol, 4% far-infrared ceramic powder, 0.09% thiophanate-methyl and 42.71% water are mixed evenly, and then 12.5% titanium dioxide, 0.4% Hydroxyethyl cellulose is dispersed into a homogenate at high speed; the homogenate is filtered through a 100-mesh sieve and dripped into a copolymer emulsion with a mass ratio of 35%, and stirred evenly at a low speed to obtain the fruit tree protective film agent of the present invention.

Example 3

Preparation of copolymer emulsion: Dissolve 0.15% sodium sulfite and 0.28% ammonium persulfate in 12% water according to the mass ratio to prepare a mixed solution of sodium sulfite and ammonium persulfate.

First add 20% water to dissolve 0.63% polyvinyl alcohol in the reaction kettle according to the mass ratio, then add 1.8% sodium lauryl sulfate, 3.61% OP-10 and 5.53% water, dissolve and filter again To remove impurities, control the temperature of the water bath at 30±2°C, then add a mixture of vinyl acetate, butyl acrylate, methyl methacrylate and acrylic acid dropwise, the mixture consists of 30% vinyl acetate, 20% butyl acrylate , 5% methyl methacrylate and 1% acrylic acid. After full emulsification, add one-third of the mixed solution of sodium sulfite and ammonium persulfate dropwise, adjust the pH value to 6-7 with sodium bicarbonate, add the remaining mixed solution of sodium sulfite and ammonium persulfate dropwise after a period of constant temperature, and keep warm for 2 hours. After cooling, the output is the copolymer emulsion.

Preparation of protective film agent: 0.7% sodium hexametaphosphate, 1% sodium polyacrylate, 0.3% 2-amino-2-methyl-1-propanol (AMP-95), 1% dodeca Carbon alcohol ester, 0.4% polypropylene glycol, 2.8% ethylene glycol, 6% far-infrared ceramic powder, 0.1% thiophanate-methyl and 32.2% water are mixed evenly, then add 15% titanium dioxide, 0.5% Hydroxyethyl cellulose is dispersed into a homogenate at high speed; the homogenate is filtered through a 100-mesh sieve and dripped into a copolymer emulsion with a mass ratio of 40%, and stirred evenly at a low speed to obtain the fruit tree protective film agent of the present invention.

In order to verify the actual effect of the present invention and provide a scientific basis for future promotion, related experiments were carried out in the apple orchard of Shenyang Agricultural University from 2011 to 2013.

The test apple orchard was planted in May 2006. The rootstock and panicle combination of the variety is 'Hanfu/GM256/Shandingzi', running north-south, the spacing between plants and rows is 2.0m×4.0m, slender and spindle-shaped, and the soil is clay loam and pH The value is 6.3, and the contents of organic matter, available nitrogen, available phosphorus and available potassium are 8.6g·kg ^-1 , 50.6g·kg ^-1 , 35.2g·kg ^-1 and 77.0g·kg ^-1 respectively.

Table 1 is the impact of the fruit tree protective film agent of the present invention on the water loss rate of apple annual branches

handle name Branch water loss rate (%) blank control 2.42 Protective film agent of the present invention 1 2.22 Protective film agent of the present invention 2 2.17 Protective film agent of the present invention 3 2.19

The results in Table 1 show that the fruit tree protective film agent of the present invention reduces the water loss of the branches while ventilating, ensures a certain water content of the branches, and plays a protective role in stabilizing the internal cell structure of the branches in the dormant period and maintaining physiological metabolic activities. At the same time, the normal respiration and water exchange of branches were not inhibited by the fruit tree protective film agent.

Table 2 Effects of fruit tree protective film agents on the electrolyte exudation rate of apple annual branches under low temperature stress

Processing temperature (°C) -20 -25 -30 -35 -40 -45 Blank control (%) 30.92 32.16 37.78 54.89 72.03 83.31 Protective film agent 1 of the present invention (%) 34.55 36.93 40.41 50.54 68.24 75.74 Protective film agent 2 of the present invention (%) 30.73 37.71 41.68 48.18 67.74 76.05 Protective film agent of the present invention 3 (%) 33.80 38.08 41.25 46.52 57.60 75.74

It can be seen from Table 2 that the electrolyte exudation rate of apple annual branches increases with the decrease of treatment temperature, and the electrolyte exudation rate of blank control is significantly higher than that of other treatments. According to the electrolyte exudation rate fitting Logistic equation to calculate the semi-lethal temperature between each treatment: blank control is -30.7 ℃, embodiment 1, 2 and 3 are respectively -31.52 ℃, -32.29 ℃ and -33.22 ℃, the treatment is all lower Compared with the control, it shows that the protective film agent for fruit trees can slow down the film damage of branches caused by low temperature stress, and reduce the rate of plant electrolyte exudation. The invention effectively resists the direct damage of low temperature to plants, and the formed protective film is beneficial to maintain the internal stability of cells, improves the adaptability of apple branches to low temperature, and thus has the effect of protecting against cold and heat preservation.

Table 3 Fruit tree protective film agent on apple annual branches under low temperature stress

Effect of malondialdehyde content (μmol·g ^-1 )

Processing temperature (°C) -20 -25 -30 -35 -40 -45 Blank control (μmol·g ^-1 ) 26.24 32.04 37.25 45.26 52.67 47.63 Protective film agent 1 of the present invention (μmol·g ^-1 ) 25.59 29.15 34.64 39.28 44.30 42.90 Protective film agent 2 of the present invention (μmol·g ^-1 ) 22.39 26.57 31.47 39.48 39.42 47.26 Protective film agent 3 of the present invention (μmol·g ^-1 ) 23.47 27.17 32.98 38.83 39.63 41.71

As can be seen from Table 3, the protective film agent for fruit trees of the present invention reduces the direct damage of low temperature to branches, and the protective layer formed simultaneously maintains the internal temperature of some branches, so that the membrane quality peroxidation is alleviated, and the membrane structure and membrane function are protected.

Table 4 protective film agent on apple annual branches under low temperature stress

Effect of SOD (superoxide dismutase) activity (U g ^-1 FW)

Processing temperature (°C) -20 -25 -30 -35 -40 -45 Blank control (U·g ^-1 FW) 162.51 209.47 268.63 242.04 179.92 152.26 Protective film agent 1 of the present invention (U·g ^-1 FW) 162.45 233.63 282.22 250.96 196.59 153.35 Protective film agent 2 of the present invention (U·g ^-1 FW) 167.98 241.63 276.61 257.24 181.14 156.38 Protective film agent 3 of the present invention (U·g ^-1 FW) 159.27 232.95 282.66 244.58 176.54 148.61

As can be seen from Table 4, within a certain range of low temperature stress, the protective film agent for fruit trees of the present invention can form an internal thermal insulation environment while maintaining heat, so that the generation of free radicals is greater than the elimination of branches under the induction of low temperature stress. Induce the increase of SOD activity to scavenge excessive free radicals, maintain normal metabolism, and protect plant cell membranes from excessive low temperature damage. But after exceeding the half-lethal temperature, SOD activity is affected.

Table 5 protective film agent on apple annual branches under low temperature stress

Effect of POD (peroxidase) activity (U min ^-1 g ^-1 FW)

Processing temperature (°C) -20 -25 -30 -35 -40 -454 --> Blank control (U min ^-1 g ^-1 FW) 13.75 16.11 22.12 26.33 19.51 12.64 Protective film agent 1 of the present invention (U min ^-1 g ^-1 FW) 14.54 17.32 22.36 27.86 17.40 13.37 Protective film agent 2 of the present invention (U min ^-1 g ^-1 FW) 12.69 17.74 23.97 27.98 20.01 12.95 Protective film agent 3 of the present invention (U min ^-1 g ^-1 FW) 13.20 16.51 24.44 28.55 21.73 13.43

It can be seen from Table 5 that within a certain range of low temperature stress, the POD activity of Hanfu apple branches treated with the fruit tree protective film agent of the present invention is significantly higher than that of the control. The invention maintains the normal metabolic state in the plant body and at the same time suppresses the bad influence of the external low temperature environment on the apple branches. But after exceeding the half-lethal temperature, POD activity is affected.

Table 6 protective film agent on apple annual branches under low temperature stress

Effect of CAT (catalase) activity ( _{μmolH2O2 g} ^-1 FW)

Processing temperature (°C) -20 -25 -30 -35 -40 -45 Blank control (μmolH ₂ O ₂ ·g ^-1 FW) 6.28 7.85 10.58 24.74 20.21 14.14 Protective film agent 1 of the present invention (μmolH ₂ O ₂ ·g ^-1 FW) 6.54 8.06 14.41 25.46 21.79 12.64 Protective film agent 2 of the present invention (μmolH ₂ O ₂ ·g ^-1 FW) 6.51 8.37 15.47 26.62 24.16 14.07 Protective film agent 3 of the present invention (μmolH ₂ O ₂ ·g ^-1 FW) 7.40 8.39 15.56 28.71 20.22 13.73

The results in Table 6 show that low temperature induces the CAT activity of plants to increase, which can eliminate the damage of H ₂ O ₂ to cells. The protective film agent for fruit trees of the invention can effectively reduce the degree of low temperature stress, increase the activity of CAT of apple branches, and reduce the degree of peroxidation of its membrane lipids. But after exceeding the half-lethal temperature, CAT activity is affected.

The fruit tree protective film agent of the present invention is applied to the top flower buds of Hanfu apples in the overwintering period, and it is found that the germination of the flower buds is delayed for more than 10 days after the treatment, which is beneficial for the flower buds to avoid continuous low temperature damage in early spring.

It is found through long-term outdoor observation that the protective film agent for fruit trees of the present invention does not crack during the overwintering period, and the film layer does not fall off in case of rain, and has good durability.

The invention improves the response of the fruit trees to low temperature stress and at the same time alleviates the alternation of freezing and thawing of the tree body, protects the cortex and cambium of the tree body, resists sunburn, and prevents the occurrence of fruit tree rot and dry rot. Delaying the germination time of flower buds can avoid the harm of late frost, and it can also prevent the saplings from overwintering.

Claims (2)

1. A low-temperature resistant protective film for fruit trees is characterized in that: its raw material composition and mass percentage examples are: Sodium hexametaphosphate 0.3%-0.7%, sodium polyacrylate 0.5%-1%, 2-amino-2-methyl-1-propanol 0.2%-0.3%, dodecyl alcohol ester 0.8%-1%, poly Polypropylene glycol 0.1%-0.4%, ethylene glycol 2.5%-2.8%, far-infrared ceramic powder 2%-6%, thiophanate-methyl 0.08%-0.1%, titanium dioxide 10%-15%, hydroxyethyl fiber Su 0.3%-0.5%, copolymer emulsion 30%-40%, the balance is water, the total amount is 100%; The components and mass percentages of the above copolymer emulsion are: sodium sulfite 0.01%-0.15%, ammonium persulfate 0.07%-0.28%, polyvinyl alcohol 0.45%-0.63%, sodium dodecyl sulfate (SDS) 1.28%-1.8 %, non-ionic alkylphenol polyoxyethylene ether (OP–10) 2.57%-3.61%, vinyl acetate 25%-30%, butyl acrylate 15%-20%, methyl methacrylate 1%- 5%, acrylic acid 0.5%-1%, sodium bicarbonate to slightly adjust the pH value, the balance is water, the total amount is 100%. 2. a preparation method of fruit tree low temperature resistant protective film agent as claimed in claim 1, is characterized in that the steps are as follows: (1) Preparation of copolymer emulsion: Dissolve 0.01%-0.15% sodium sulfite and 0.07%-0.28% ammonium persulfate in 10%-12% water according to the mass ratio to make a mixed solution of sodium sulfite and ammonium persulfate; Add 15%-20% water to the reactor first, then gradually add and dissolve 0.45%-0.63% polyvinyl alcohol, 1.28%-1.8% sodium lauryl sulfate, 2.57%-3.61% Non-ionic alkylphenol polyoxyethylene ether (OP-10) and 5.53%-29.12% water, after dissolving, filter repeatedly to remove impurities, control the water bath temperature at 30±2°C; then add vinyl acetate and butyl acrylate dropwise A mixture of esters, methyl methacrylate and acrylic acid, the mixture consists of 25%-30% vinyl acetate, 15%-20% butyl acrylate, 1%-5% methyl methacrylate and 0.5% -1% acrylic acid composition; after full emulsification, add dropwise one-third of the mixed solution of sodium sulfite and ammonium persulfate, adjust the pH value to 6-7 with sodium bicarbonate, and add the remaining sodium sulfite and ammonium persulfate dropwise after a period of constant temperature Mix the solution, keep it warm for 2 hours and cool it down to get the copolymerized emulsion; (2) Preparation of protective film agent: 0.3%-0.7% sodium hexametaphosphate, 0.5%-1% sodium polyacrylate, 0.2%-0.3% 2-amino-2-methyl-1 -Propanol, 0.8%-1% dodecyl alcohol ester, 0.1%-0.4% polypropylene glycol, 2.5%-2.8% ethylene glycol, 2%-6% far-infrared ceramic powder, 0.08%-0.1% methyl Mix thiophanate and 32.2%-53.22% water evenly, then add 10%-15% titanium dioxide and 0.3%-0.5% hydroxyethyl cellulose according to the mass ratio, and disperse into a homogenate at high speed; the homogenate is passed through a 100-mesh sieve After filtering, add 30%-40% copolymer emulsion dropwise, and stir evenly at low speed to form a protective film agent.