Preparation method of antidote for overcoming vegetable continuous cropping obstacles

Abstract

The present invention belongs to the technical field of vegetable seedling cultivation, and discloses a method for preparing an antidote for overcoming vegetable continuous cropping obstacles, comprising the following steps: desalting, acidifying, screening, and mixing wood ash to obtain the antidote. The present invention uses wood ash instead of activated carbon to adsorb the self-toxic phenolic acid substances that cause continuous cropping obstacles, thereby overcoming or reducing the agricultural losses caused by continuous cropping obstacles, and can simultaneously provide a variety of mineral nutrients required by crops. Compared with the activated carbon currently sold on the market, it has a huge price advantage, can achieve the comprehensive utilization of straw power plant waste wood ash while overcoming continuous cropping obstacles, and has significant social, economic and ecological benefits.

Description

Technical Field

[0001] The invention belongs to the technical field of vegetable seedling cultivation, relates to overcoming the obstacle of continuous vegetable cropping, and particularly relates to a preparation method of an antidote for overcoming the obstacle of continuous vegetable cropping. Background Art

[0002] Continuous cropping disorder refers to the phenomenon of reduced yield, deteriorating quality, and poor growth conditions when the same crop or closely related crops are continuously planted on the same soil, even with normal cultivation and management practices. Continuous cropping disorder is a serious problem for vegetables and is caused by a variety of factors, including a deterioration of the soil's biological environment, which leads to an imbalance in microbial populations and affects soil biological activity; deterioration of soil physical and chemical properties, which results in a shallower tillage layer, reduced permeability, and increased bulk density, hindering the growth and development of crop roots and the effective absorption of soil nutrients; soil nutrient imbalance, resulting in a deficiency of some nutrients and a decrease in soil fertility; and secondary salinization and acidification of the soil. Numerous studies have examined this issue, which can be addressed through biological control, the selection of varieties resistant to continuous cropping, grafting, or the application of increased organic fertilizers.

[0003] Phenolic acids, produced by plants through tissue secretion or residue decomposition, have allelopathic effects, inhibiting the growth and development of neighboring or subsequent plants. Phenolic acids in continuously cropped soils are a major cause of continuous cropping problems in vegetables. These include phlorizin, phloridzin, p-hydroxybenzoic acid, syringic acid, vanillic acid, mandelic acid, benzoic acid, caffeic acid, and ferulic acid. Wu Fengzhi's research has shown that phenylacrylic acid and p-hydroxycinnamic acid inhibit the growth of cucumber seedlings, reducing fresh weight, plant height, stem diameter, and leaf area. The inhibitory effect increases with increasing treatment concentration. Sun Huijun et al. have shown that treatment with benzoic acid and cinnamic acid can cause nuclear deformation, nucleolus abnormalities, sparse cytoplasm, and increased and enlarged vacuoles in root tip cells. Zou Liyun et al. have shown that watermelon autotoxicity is a key factor in continuous cropping problems in watermelon. Research on phenolic acid allelopathic substances has been a hot topic and a challenge in the study of continuous cropping problems.

[0004] Studies have shown that activated carbon effectively adsorbs and detoxifies exogenous phenolic acids, inactivating them. Li Yumei et al. found that high concentrations of clomazone residues in soil inhibited corn growth. However, adding biochar suppressed the harmful effects of high concentrations of clomazone residues in the soil, leading to better corn growth and increased yields. However, activated carbon is expensive and has little practical value in production.

[0005] In recent years, a number of straw-based power plants have been built across the country, generating large quantities of plant ash. However, due to its low bulk density, high packaging and transportation costs, and inconvenient field application, attempts to directly use all the plant ash from these plants as agricultural fertilizer have proven challenging. The ash is often dumped and buried by power plants, wasting resources and polluting the environment. Furthermore, the plant ash produced by these plants contains over 10% unburned charcoal, a substance with properties similar to activated carbon. Besides residual charcoal, the ash also contains a large amount of porous silica, which has a certain surface adsorption capacity. However, research on using plant ash to overcome continuous cropping problems has been largely unreported in China. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a method for preparing an antidote for overcoming the continuous cropping of vegetables. The present invention uses wood ash as raw material to prepare the antidote, which absorbs phenolic acid self-toxic substances that cause continuous cropping problems, thereby alleviating or overcoming the continuous cropping problems of vegetables.

[0007] The present invention is achieved through the following technical solutions:

[0008] The preparation method of an antidote for overcoming vegetable continuous cropping obstacles comprises the following steps: desalting, acidifying, sieving and mixing plant ash to obtain the antidote.

[0009] A further improvement of the present invention is:

[0010] The desalination process is to wash the salt in the ash with water to reduce the soluble salt content in the ash to a conductivity measurement value of less than 2ms / cm. The conductivity measurement conditions are: 25°C, and a volume ratio of ash to water of 1:5.

[0011] Furthermore, the acid adjustment process is to use an acidic substance to adjust the pH of the desalted wood ash to 6-8.

[0012] Furthermore, the acidic substance is humic acid, ferrous sulfate, sulfuric acid or a mixture of ferrous sulfate and sulfuric acid, and the amount of the acidic substance is 10%-15% of the weight of the wood ash.

[0013] Furthermore, the screening process is to pass the acid-adjusted wood ash through a 40-mesh sieve to remove large particles such as nails and unburned sawdust.

[0014] A further improvement of the present invention is:

[0015] The antidote obtained by the above method is used to overcome the obstacle of continuous cropping of vegetables.

[0016] Furthermore, the application process is to use the antidote in an amount of 2 to 8% of the weight of water when raising seedlings of vegetable crops.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention uses wood ash instead of activated carbon to absorb the self-toxic phenolic acids that cause continuous cropping problems, thereby overcoming or mitigating agricultural losses caused by continuous cropping problems while also providing a variety of mineral nutrients required by crops. This method offers a significant price advantage over currently available activated carbon, overcomes continuous cropping problems, and achieves comprehensive utilization of wood ash, a waste product from straw power plants, offering significant social, economic, and ecological benefits. DETAILED DESCRIPTION

[0019] The present invention is described in detail below with reference to specific embodiments.

[0020] Example 1

[0021] (1) Use water to wash away the salt in the wood ash, so that the soluble salt content in the wood ash is reduced to a conductivity measurement value below 2ms / cm. The conductivity measurement conditions are: 25℃, and the volume ratio of wood ash to water is 1:5.

[0022] (2) Add ferrous sulfate, sulfuric acid, or a mixture of ferrous sulfate and sulfuric acid to the desalted wood ash and adjust the pH value to 6-8.

[0023] (3) The desalted and acid-adjusted wood ash is passed through a 40-mesh sieve to remove large particles such as nails and unburned sawdust.

[0024] (4) Using a blender or other equipment, the desalted, acidified and sieved wood ash is stirred evenly to obtain an antidote.

[0025] Example 2: Verification of detoxification effect

[0026] Test materials and methods:

[0027] Phenolic acid: analytically pure p-hydroxybenzoic acid, phenylacrylic acid

[0028] Crops: cucumber (multi-node), tomato (Cooperation 906), antidote: the wood ash antidote obtained in Example.

[0029] Experimental Method: Seeds were sown on folded filter paper, placed in a plastic bag, and incubated in an oven at 25°C. Fifty seeds were sown per bag, 25 on each side. Each treatment was replicated three times. Germination rates, root length, and hypocotyl length of cucumbers and tomatoes were assessed starting 48 hours after sowing.

[0030] 1. Effects of exogenous phenolic acids on seed germination and sprout growth of tomato and cucumber

[0031] Parahydroxybenzoic acid and phenylacrylic acid were prepared into three different concentration solutions of 150 mg / l, 300 mg / l, and 600 mg / l. Tomato and cucumber were used as indicators to observe their effects on seed germination and sprout growth. The results are shown in Tables 1 to 4.

[0032] The results in Table 1 show that p-hydroxybenzoic acid at concentrations above 300 mg / l significantly inhibited the elongation of the hypocotyl of tomato sprouts. At 600 mg / l, all measured indicators dropped below 60% of the blank control, demonstrating a strong toxic effect.

[0033] Table 1 Effects of different concentrations of p-hydroxybenzoic acid on tomato germination and sprout growth

[0034]

[0035] As shown in Table 2, the effect of p-hydroxybenzoic acid on the germination and growth of cucumber sprouts is smaller than that on tomatoes. When the concentration is below 300 mg / l, it shows a certain promoting effect, especially on the elongation of young roots and hypocotyls. However, when the concentration increases to 600 mg / l, it also shows a significant inhibitory effect.

[0036] Table 2 Effects of different concentrations of p-hydroxybenzoic acid on cucumber germination and sprout growth

[0037]

[0038]

[0039] Table 3 shows that phenylacrylic acid had a weak inhibitory effect on tomato growth. Only the length of the embryonic axis of the young shoots showed a regular decrease with increasing phenylacrylic acid concentration. However, germination rate and root length showed some promotion. This may be related to the low maximum phenylacrylic acid concentration (400 mg / l) used in this experimental design.

[0040] Table 3 Effects of different concentrations of phenylacrylic acid on tomato germination and sprout growth

[0041] Phenylacetic acid (mg / l) Fresh weight (g) root Germination rate (%) Root length (cm) Hypocotyl length (cm) 0 1.02 90.7 3.73 3.19 150 0.94 92 3.62 3.00 300 1.01 96 3.82 2.89 400 0.96 93 4.14 2.82

[0042] As shown in Table 4, unlike tomatoes, phenylacrylic acid showed a significant inhibitory effect on the germination rate and root elongation of cucumber, but a promoting effect on the hypocotyl length. Even when the concentration reached 400 mg / l, the hypocotyl length of cucumber sprouts was still more than 30% higher than that of the blank control.

[0043] Table 4 Effects of different concentrations of phenylacrylic acid on cucumber germination and sprout growth

[0044] Phenylacetic acid (mg / l) Fresh weight (g) Germination rate (%) Root length (cm) Hypocotyl length (cm) 0 8.37 100 5.70 3.56 150 7.35 98 5.87 4.55 300 10.17 90 4.36 4.74 400 6.35 88 4.45 4.40

[0045] 2. Adsorption of two phenolic acids by activated carbon and its effect on eliminating the phenolic acid toxicity of cucumber

[0046] Cucumber was used as the indicator crop. Activated carbon was added to prepared phenolic acid solutions of varying concentrations at a dosage of 2% (based on the weight of the activated carbon in water). Germination tests were conducted on filter paper. Pure water and phenolic acid solutions of equal concentration without activated carbon served as controls. The results are shown in Tables 5-6.

[0047] Table 5 Effect of activated carbon on the physiological effects of p-hydroxybenzoic acid

[0048]

[0049]

[0050] The results showed that the significant toxic effect of 600 mg / l p-hydroxybenzoic acid on cucumber was completely eliminated after adding 2% activated carbon. Compared with the case without adding activated carbon, the activated carbon significantly increased the length of the roots and hypocotyls when the same 600 mg / l p-hydroxybenzoic acid was added.

[0051] Table 6 Effect of activated carbon on the physiological effects of phenyl acrylic acid

[0052]

[0053] As shown in Table 6, the addition of activated carbon also relieved the inhibitory effect of phenylacrylic acid on cucumber. At a concentration of 400 mg / l phenylacrylic acid, the addition of activated carbon increased the length of cucumber rootlets and hypocotyls by 30-40%.

[0054] 3. The detoxification effect of the plant ash detoxifier of the present invention on exogenous phenolic acids and its promoting effect on the growth of young shoots

[0055] The test was based on the use of 8% of the weight of the water as the antidote, and compared the effects of two phenolic acids at different concentrations on tomato seed germination and sprout growth, and compared with the corresponding concentration of phenolic acid solution without adding wood ash. The results are shown in Tables 7 and 8.

[0056] The addition of wood ash as a detoxifier significantly reduced the inhibitory effects of high concentrations of parahydroxybenzoic acid on tomato seed germination and sprout growth. Root and hypocotyl length, where 600mg / l parahydroxybenzoic acid exerted the strongest toxicity, increased by 2.5-3 times after adding 8% wood ash.

[0057] Table 7 Effects of different concentrations of p-hydroxybenzoic acid on tomato germination and seedling growth under 8% wood ash conditions

[0058]

[0059]

[0060] Table 8 Effects of different concentrations of phenylacrylic acid on tomato germination and seedling growth under 8% wood ash conditions

[0061]

[0062] As shown in Tables 7 and 8, the addition of wood ash detoxifier (8%) relieved the inhibitory effect of phenylacrylic acid on the hypocotyls of tomato sprouts, and the hypocotyl length increased by more than 50% compared to the corresponding hypocotyls without wood ash addition. This shows that wood ash has a reliable detoxifying effect on phenylacrylic acid.

[0063] 4. Detoxification effect of different dosages of wood ash detoxifier on exogenous phenolic acids

[0064] Based on the previous study using 2% activated carbon, the wood ash detoxifier dosage was quadrupled to a maximum of 8%. The adsorption and detoxification effects of different wood ash detoxifier dosages on two phenolic acids at different concentrations were compared. The experimental results are shown in Tables 9-12.

[0065] Table 9 Effects of different wood ash dosages on tomato germination and sprout growth under 600 mg / l p-hydroxybenzoic acid conditions

[0066]

[0067] As shown in Table 9, the significant inhibitory effect of 600 mg / l p-hydroxybenzoic acid on various indicators of tomato sprouts was eliminated after adding different amounts of wood ash. The results showed that under the experimental conditions, the effect of 2% wood ash was similar to that of 8%.

[0068] Table 10 Effects of different wood ash dosages on tomato germination and sprout growth under 400 mg / l phenylacrylic acid

[0069]

[0070]

[0071] As shown in Table 10, at a concentration of 400 mg / l of phenylacrylic acid, the inhibitory effect of phenylacrylic acid on the length of tomato rootlets and hypocotyls could be eliminated by adding different amounts of wood ash. Under the conditions of this experimental design, there was little difference between the different amounts of wood ash used, indicating that the proportion of wood ash used could be further reduced.

[0072] Table 11 Effects of different wood ash dosages on the physiological effects of 600 mg / l parahydroxybenzoic acid (cucumber)

[0073]

[0074] As shown in Table 11, the significant inhibitory effect of 600 mg / l p-hydroxybenzoic acid on various indicators of cucumber sprouts was eliminated after adding different amounts of wood ash. The effects of 2% and 8% wood ash were similar, which was consistent with the tomato test results.

[0075] Table 12 Effects of different wood ash dosages on the physiological effects of 400 mg / l phenylacrylic acid (cucumber)

[0076]

[0077] As shown in Table 12, under the condition of 400 mg / l phenylacrylic acid concentration, adding different amounts of wood ash, phenylacrylic acid lifted the inhibition on the length of cucumber rootlets and hypocotyls, and showed a certain promoting effect.

[0078] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. The application of the antidote in overcoming the obstacle of continuous cropping of vegetables is characterized in that: The application process is to use the detoxifier in an amount of 2-8% of the weight of water when raising vegetable seedlings; the vegetable continuous cropping obstacle is caused by phenolic acid self-toxic substances; The antidote is prepared by the following steps: desalting, acidifying, sieving and mixing wood ash to obtain the antidote.

2. The use according to claim 1, characterized in that: The desalination process is to wash the salt in the wood ash with water, so that the soluble salt content in the wood ash is reduced to a conductivity measurement value of less than 2ms / cm.

3. The use according to claim 1, characterized in that: The acid adjustment process is to use an acidic substance to adjust the pH of the desalted wood ash to 6-8.

4. The use according to claim 3, characterized in that: The acidic substance is humic acid, ferrous sulfate, sulfuric acid or a mixture of ferrous sulfate and sulfuric acid, and the amount of the acidic substance is 10%-15% of the weight of the wood ash.

5. The use according to claim 1, characterized in that: The screening process is to pass the acid-adjusted wood ash through a 40-mesh sieve to remove nails, large particles of unburned sawdust.

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