Pine needle leaf compound fertilizer as well as preparation method and application thereof

Abstract

The invention discloses a pine needle leaf compound fertilizer and a preparation method and application thereof, and belongs to the technical field of agricultural fertilizer.The pine needle leaf compound fertilizer is prepared from, by weight, 30-80 parts of pine needle leaf organic granular fertilizer and 20-70 parts of conventional compound fertilizer, and the pine needle leaf organic granular fertilizer is prepared from, by weight, 0-50 parts of pine needle leaf extract and 0-50 parts of conventional compound fertilizer. 10 to 50 parts of pine needle leaf extract and 20 to 80 parts of pine needle leaf biomass charcoal. The pine needle leaf organic granular fertilizer and the conventional compound fertilizer are mixed, so that the soil quality can be improved by utilizing the characteristics of the pine needle leaf organic granular fertilizer, and the defect of low nutrient utilization rate of the compound fertilizer can be overcome. When the morning glory culture medium is used for morning glory culture, the crown breadth, plant height and leaf chlorophyll content of morning glory are remarkably increased, the corolla diameter of morning glory after flowering is prolonged, and the flowering number of a single plant is increased.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural fertilizers, in particular to a pine needle compound fertilizer and a preparation method and application thereof. Background Art

[0002] Chemical fertilizers, as one of the most common agricultural production materials, offer the advantages of high efficiency and rapid results, effectively increasing the yield of various agricultural products. However, the long-term and extensive use of chemical fertilizers in pursuit of increased agricultural output value and yield can cause a series of environmental problems, including soil degradation, compaction, acidification, and salinization. Furthermore, over 30% of fertilizer is lost through water during fertilization, resulting in resource waste and environmental pollution. Organic fertilizers, on the other hand, can improve soil structure, enhance water retention and aeration capacity, thereby increasing soil fertility. They can also reduce reliance on chemical fertilizers, lower agricultural production costs, and minimize environmental pollution from chemical substances. However, their slow decomposition, delayed effects, complex composition, and wide variability in fertilizer efficiency, as well as difficulty in accurately controlling fertilizer application rates, limit their widespread application. Pine trees are a very ancient plant, widely distributed and abundant worldwide. Their pine needles are rich in nutrients, making them widely used as organic fertilizers for flowers, grasses, and crops. However, pine needles alone lack comprehensive nutritional value, and their benefits cannot be quickly and intuitively demonstrated when used alone. For example, CN105315092B discloses a pine needle organic fertilizer application, which uses an organic solvent extract of pine needles to concentrate into an extract, and then adds the remaining fiber after the organic solvent extraction of the pine needles to a biogas residue or peat after fermentation in a biogas tank to make a granular fertilizer to improve the quality of flowering and fruit. However, the pine needle organic fertilizer still has the problems of low nutritional content, easy loss of fertility, and the need for small amounts of multiple fertilization. Therefore, it is still necessary to develop a compound fertilizer that simultaneously meets the requirements of high fertilizer efficiency, comprehensive nutrition, and stable and long-lasting fertility release to meet the needs of agricultural production. Summary of the Invention

[0003] The purpose of the present invention is to provide a pine needle compound fertilizer, which utilizes abundant pine needle resources as the effective ingredient of organic fertilizer, combined with conventional compound fertilizer, to achieve high fertilizer efficiency, comprehensive nutrition, stable and long-lasting fertility release while minimizing damage to the environment to the greatest extent.

[0004] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0005] A pine needle compound fertilizer comprises, by weight, 30-80 parts of pine needle organic granular fertilizer and 20-70 parts of conventional compound fertilizer. The pine needle organic granular fertilizer comprises, by weight, 0-50 parts of pine needle extract, 10-50 parts of pine needle extract, and 20-80 parts of pine needle biochar.

[0006] Preferably, the mass ratio of the pine needle leaf extract to the pine needle leaf extract is (1-4): (4-1); further preferably, the mass ratio of the pine needle leaf extract to the pine needle leaf extract is (1.5-3): (3.5-3).

[0007] After the pine needles are extracted with an organic solvent, they are further extracted with an extractant to further concentrate the nutrients they contain, so that the unit volume of granular fertilizer contains more nutrients.

[0008] Biochar has a rich pore structure and a high specific surface area, and has an adsorption effect on nutrient ions. As a carrier of pine needle extracts / extracts and conventional compound fertilizers, it can prolong the release time of fertilizer nutrients. Compared with conventional carriers or organic fertilizers without carriers, it has a better slow-release effect.

[0009] Preferably, the mass ratio of the pine needle organic granular fertilizer to the conventional compound fertilizer is (3-7):(7-3); further preferably, the mass ratio of the pine needle organic granular fertilizer to the conventional compound fertilizer is (4-6):(6-4).

[0010] Preferably, the weight portion of the pine needle biomass charcoal is 50-60 parts.

[0011] Preferably, the extractant used in the pine needle extract is at least one of ethanol or methanol; the extractant used in the pine needle extract is at least one of petroleum ether, ethyl acetate and n-butanol. Preferably, the solid-liquid ratio of the pine needle extract to the extractant is 1:(2-5).

[0012] Further preferably, the extractant used in the pine needle leaf extract is ethyl acetate.

[0013] Specifically, the pine needle leaf extract is obtained by further extracting the pine needle leaf extract.

[0014] Specifically, the preparation method of the pine needle biomass charcoal is to dry the residue remaining after pine needle extraction and then calcine it for carbonization, the carbonization temperature is 400-600° C., and the carbonization time is 6-8 hours.

[0015] Preferably, the specific surface area of the pine needle biochar is 1000-2000m 2 / g. When the biochar specific surface area is within this range, the slow-release effect is optimal. The specific surface area is measured using the BET method according to standard GB / T 19587-2017.

[0016] Specifically, the effective ingredients of the conventional compound fertilizer are nitrogen ≥6%, phosphorus pentoxide ≥7%, and potassium oxide ≥12%.

[0017] The present invention also claims a method for preparing a compound fertilizer from pine needles, comprising the following steps: S1. drying and pulverizing pine needles, and sieving to obtain a solid powder with uniform particle fineness; S2. extracting the powder by solvent extraction and concentrating it by rotary evaporation to a dark green extract to obtain a pine needle extract; S3. dissolving the pine needle extract in distilled water, extracting with an extractant, separating the aqueous phase and the organic phase, and concentrating the organic phase under reduced pressure to dryness to obtain a pine needle extract; S4. drying and carbonizing the waste residue after extraction in S2 to obtain pine needle biochar; S5. uniformly mixing the pine needle extract, pine needle extract and pine needle biochar obtained in S2, S3 and S4 according to a ratio, granulating to obtain an organic granular fertilizer; S6. mixing the organic granular fertilizer obtained in S5 with a conventional compound fertilizer according to a ratio to obtain a pine needle compound fertilizer.

[0018] Preferably, in step S1, the pine needles are dried, pulverized and sieved through a 80-100 mesh sieve.

[0019] The present invention also protects the application of the pine needle compound fertilizer for cultivating morning glories.

[0020] Beneficial effects

[0021] The present invention provides a pine needle compound fertilizer, which is prepared by mixing a pine needle extract and biochar prepared from the waste residue after extraction, converting agricultural waste into organic fertilizer, reducing the pressure on the environment, and realizing the resource utilization of waste. The prepared organic granular fertilizer is then mixed with a conventional compound fertilizer, which can not only improve the soil quality by using the characteristics of organic fertilizer, but also make up for the defect of low nutrient utilization rate of compound fertilizer. When used for cultivating morning glories, it significantly increases the crown width, plant height and leaf chlorophyll content of morning glories, extends the corolla diameter after flowering of morning glories and increases the number of flowers per plant. Description of the drawings

[0022] Figure 1 It is the total ion chromatogram of pine needle extract 1. Detailed implementation manners

[0023] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention, but the embodiments do not impose any form of limitation on the present invention. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the technical field.

[0024] The raw materials used in the examples and comparative examples are described as follows:

[0025] Pine needle extract: self-made, obtained by drying and pulverizing pine needles, sieving through a 80-mesh sieve, and then extracting with ethanol;

[0026] Pine needle extract 1: Self-made. By dissolving pine needle extract in distilled water, extracting with ethyl acetate, the ratio of the single extraction agent to the pine needle extract is 3:1, extracting 3 times, combining the organic phases, and concentrating to obtain the ethyl acetate extract;

[0027] Pine needle extract 2: Self-made. By dissolving pine needle extract in distilled water, extracting with petroleum ether, the ratio of the single extraction agent to the pine needle extract is 3:1, extracting 3 times, combining the organic phases, and concentrating to obtain the petroleum ether extract;

[0028] Pine needle extract 3: Self-made. By dissolving pine needle extract in distilled water, extracting with n-butanol, the ratio of the single extraction agent to the pine needle extract is 3:1, extracting 3 times, combining the organic phases, and concentrating to obtain the n-butanol extract;

[0029] Pine needle biochar 1: Self-made. Obtained by drying the waste residue after pine needle extraction for 30 min and then performing calcination carbonization treatment; Its specific surface area measured by the BET method is 1126 m 2 / g;

[0030] Pine needle biochar 2: Self-made. Obtained by drying the waste residue after pine needle extraction for 1 h and then performing calcination carbonization treatment; Its specific surface area measured by the BET method is 1987 m 2 / g;

[0031] Pine needle biochar 3: Self-made. Obtained by directly performing calcination carbonization treatment on the waste residue after pine needle extraction; Its specific surface area measured by the BET method is 607 m 2 / g;

[0032] Pine needle biochar 4: Self-made. Obtained by activating the waste residue after pine needle extraction with 60% aqueous solution of KOH, washing and filtering, drying for 1 h and then performing calcination carbonization treatment; Its specific surface area measured by the BET method is 2570 m 2 / g;

[0033] Conventional compound fertilizer: Nitrogen ≥ 6%, phosphorus pentoxide ≥ 7%, potassium oxide ≥ 12%, purchased from Yantai Fuhui Agricultural Technology Co., Ltd.;

[0034] Unless otherwise specified, the component raw materials used in each example and comparative example of the present invention are all commercially available raw materials, and the component raw materials used in each parallel experiment are all of the same kind.

[0035] Examples 1 to 16 A pine needle compound fertilizer, the preparation method is as follows:

[0036] S1. First dry the pine needles at 105 °C for 30 minutes, and then dry at 65 °C for 48 hours. After drying, crush with a pulverizer and pass through an 80-mesh sieve to obtain a solid powder with uniform particle fineness;

[0037] S2. Add the sieved solid powder to 70% ethanol according to a solid-liquid ratio of 1:15 (W / V), let it stand for 60 min, extract it by ultrasonic wave (150 W) at 50 °C for 30 min, and collect the filtrate; then add 70% ethanol to the filter residue obtained by filtration again, repeat the above steps 2 times, and combine the filtrates obtained three times. The filtrate is concentrated to a dark green extract by removing the organic phase through a rotary evaporator at 55 °C to obtain pine needle extract;

[0038] S3. Completely dissolve the pine needle extract in distilled water, extract it 3 times with an extractant, and the solid-liquid ratio of the extractant to the pine needle extract per extraction is 3:1. Collect and combine the organic phases, and concentrate them through a rotary evaporator to obtain pine needle extract. Among them, the pine needle extract extracted with ethyl acetate is measured using GC / MS (6890B / 5975N gas chromatography / mass spectrometer, Agilent Technologies, USA). The total ion current chromatogram is as Figure 1 shown. Mass spectrometry analysis identified 76.54% of the peak area, indicating that the pine needle extract is mainly composed of compounds such as terpenoids (32.65%), alcohols (24.99%), alkanes (10.21%), and esters (8.69%).

[0039] S4. Dry and carbonize the waste residue after ethanol extraction in S2 at a carbonization temperature of 500 °C for 7 hours to obtain pine needle biochar;

[0040] S5. Take the pine needle extract obtained in S2, the pine needle ethyl acetate extract obtained in S3, and the pine needle biochar obtained in S4, mix them evenly to prepare an organic granular fertilizer;

[0041] S6. With a total of 100 parts, mix the organic granular fertilizer obtained in S5 with a conventional compound fertilizer according to a mass ratio to obtain a pine needle compound fertilizer.

[0042] Table 1 Raw material composition of a pine needle compound fertilizer (parts by weight)

[0043]

[0044] Continued Table 1

[0045]

[0046] Comparative Example 1

[0047] No fertilizer is applied.

[0048] Comparative Example 2:

[0049] Compared with Example 1, the difference is that no pine needle organic granular fertilizer is added.

[0050] Comparative Example 3

[0051] Compared with Example 1, the difference is that no pine needle extract and pine needle extract are added to the organic granular fertilizer, and the pine needle biochar accounts for 100%.

[0052] Control Example 4

[0053] Compared with Example 1, the difference is that no extract is added to the organic granular fertilizer, and 50 parts of pine needle extract and 50 parts of pine needle biochar are used instead.

[0054] Test Example 1

[0055] Sowing and seedling raising were carried out on April 15, 2023. Temperature and humidity management were carried out according to conventional measures to ensure the normal growth and development of morning glory seedlings. After the seedlings became mature, seedlings with the same growth amount were selected and cultivated in nutrient pots of the same specification. The test treatment method was as follows: the compound fertilizers of Examples 1-16 and Control Examples 1-4 were respectively applied to each nutrient pot at a specification of 0.15 kg / plant. The contents of nitrogen, phosphorus and potassium fertilizers in the soil were measured at this time, and then the contents of nitrogen, phosphorus and potassium fertilizers in the soil were measured again at the time points of 30 days and 60 days.

[0056] The initial available nitrogen content of the substrate used was 28.7 mg / kg, the available phosphorus content was 11.5 mg / kg, and the available potassium content was 51.6 mg / kg.

[0057] Among them, the soil hydrolyzable nitrogen was determined by the alkali hydrolysis diffusion method and titrated with sulfuric acid; the available phosphorus was extracted with 0.5 mol / L NaHCO3 and determined by the molybdenum blue colorimetric method; the available potassium was extracted with 1 mol / L NH4OAc and determined with a flame photometer. The results are shown in Table 2:

[0058] Table 2

[0059]

[0060]

[0061] Test Example 2

[0062] Sowing and seedling raising were carried out on April 15, 2023. Temperature and humidity management were carried out according to conventional measures to ensure the normal growth and development of morning glory seedlings. After the seedlings became mature, seedlings with the same growth amount were selected and cultivated in nutrient pots of the same specification. The test treatment method was as follows: the compound fertilizers of Examples 1-16 and Control Examples 1-4 were respectively applied to each nutrient pot at a specification of 0.15 kg / plant. On June 30, 2023, after the morning glory had been in bloom for some time, its crown width, plant height, leaf chlorophyll content, corolla diameter and number of flowers per plant were investigated.

[0063] Among them, the number of flowering trees was recorded by manual counting, the crown width, plant height and corolla diameter were directly measured with a vernier caliper, and the leaf chlorophyll content was measured with a chlorophyll meter. The results are shown in Table 3:

[0064] Table 3

[0065]

[0066]

[0067] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and utilize the present invention well. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A pine needle compound fertilizer, characterized in that, By weight parts, it includes 30 - 80 parts of pine needle organic granular fertilizer and 20 - 70 parts of conventional compound fertilizer. The pine needle organic granular fertilizer, by weight parts, includes 0 - 50 parts of pine needle extract, 10 - 50 parts of pine needle extractant, and 20 - 80 parts of pine needle biochar.

2. The pine needle compound fertilizer according to claim 1, characterized in that, The mass ratio of the pine needle extract to the pine needle extractant is (1 - 4):(4 - 1).

3. The pine needle compound fertilizer according to claim 1, characterized in that, The mass ratio of the pine needle organic granular fertilizer to the conventional compound fertilizer is (3 - 7):(7 - 3).

4. The pine needle compound fertilizer according to claim 1, wherein The weight parts of the pine needle biochar are 50 - 60 parts.

5. The pine needle compound fertilizer according to claim 1, characterized in that, The extractant used in the pine needle extract is at least one of ethanol or methanol; the extractant used in the pine needle extractant is at least one of ethyl acetate, petroleum ether, and n - butanol.

6. The pine needle compound fertilizer according to claim 1, characterized in that, The pine needle extractant is obtained by further extracting the pine needle extract.

7. The pine needle compound fertilizer according to claim 1, characterized in that, The preparation method of the pine needle biochar is to dry and then calcine and carbonize the residue remaining after the extraction of pine needles. The carbonization temperature is 400 - 600 °C, and the carbonization time is 6 - 8 hours. The specific surface area of the pine needle biochar is 1000 - 2000 m 2 / g.

8. The pine needle compound fertilizer according to claim 1, characterized in that, The effective components of the conventional compound fertilizer are nitrogen ≥ 6%, phosphorus pentoxide ≥ 7%, and potassium oxide ≥ 12%.

9. The preparation method of the pine needle compound fertilizer according to any one of claims 1-8, characterized in that, It includes the following steps: S1. Dry and crush the pine needles, then sieve them to obtain a solid powder with uniform particle fineness; S2. Extract the powder by the solvent extraction method and concentrate it to a dark green extract by rotary evaporation to obtain the pine needle extract; S3. Dissolve the pine needle extract in distilled water, extract it with an extractant, separate the aqueous phase and the organic phase, and concentrate the organic phase under reduced pressure to dryness to obtain the pine needle extractant; S4. Dry and carbonize the waste residue after extraction in S2 to obtain pine needle biochar; S5. Mix the pine needle extract, pine needle extractant, and pine needle biochar obtained in S2, S3, and S4 evenly according to the ratio, granulate to obtain the organic granular fertilizer; S6. Mix the organic granular fertilizer obtained in S5 with the conventional compound fertilizer according to the ratio to obtain the pine needle compound fertilizer.

10. The use of the pine needle compound fertilizer according to any one of claims 1-8, characterized in that, It is used for the cultivation of morning glories.

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