Composite preparation based on sophorolipid and PHBV bioactive preparation and method

Abstract

The invention discloses a composite preparation based on sophorolipid and a PHBV bioactive preparation and a method, and belongs to the field of saline soil improvement. The preparation method comprises the following steps: dissolving the sophorolipid and the PHBV bioactive preparation in water, and uniformly mixing to obtain the compound preparation. Before crops are planted, the compound preparation is irrigated in saline-alkali soil where oil sunflower crops need to be planted; under the synergistic effect of sophorolipid and the PHBV bioactive preparation, the physicochemical properties of the saline-alkali soil can be improved, the growth and development of plants are promoted, and the stress resistance of oil sunflower crops is improved. The compound preparation disclosed by the invention can effectively improve growth indexes (such as plant height, plant diameter, fresh weight, dry weight, leaf number, flower disc diameter and the like) of plants and increase the grain yield at the same time, so that the limitation of limited plant growth and yield improvement in the saline-alkali soil improvement process in the prior art is overcome.

Description

Technical Field

[0001] The present invention belongs to the field of improvement of saline-alkali soil or alkaline soil, and particularly relates to a composite preparation based on sophorolipid and PHBV bioactive preparation, a preparation method, and a method for promoting the growth of sunflower crops in saline-alkali soil. Background Art

[0002] Saline-alkali land is a type of obstructive land where salts are excessively enriched, leading to soil degradation. It is a general term for soils including saline soil and alkaline soil with a salt content of more than 0.1% and an alkalization degree exceeding 15% and less than 20%. It is estimated that the area of saline-alkali soil is increasing at a rate of 1-2% per year, and soil salinization seriously restricts the sustainable use of water and soil resources and the improvement of crop yields (such as sunflower, rapeseed, etc.).

[0003] Improving and utilizing saline-alkali soil can not only alleviate the arable land crisis, increase crop yields, and promote food security, but also improve the agricultural ecological environment and people's quality of life. Researchers have conducted a large number of studies on the physical and chemical properties and structure of saline-alkali soil, the microbial structure and function, and the growth effects of plants, and have proposed soil improvement measures targeted at different saline-alkali soils. At present, saline-alkali land improvement technologies can be divided into physical improvement, chemical improvement, biological improvement, and engineering improvement. However, physical methods require a large amount of manpower and high implementation costs, biological methods are very time-consuming, and are often restricted by environmental factors. In addition, some modern technologies and reclamation methods for saline-alkali soil, such as genetic and electro-improvement, are limited due to their high costs and low efficiency. In contrast, chemical methods are considered to be the most effective and widely used methods for improving saline-alkali soil, but they often can only change a certain property of the soil. Therefore, the combination of modifiers has become a potential strategy for effectively alleviating the salt stress of saline-alkali soil.

[0004] In contrast, sophorolipid, as a biosurfactant produced by Candida (such as Candida bombicola) through fermentation, not only has good surface activity but also has biodegradability. The production process of sophorolipid uses fish oil and glucose as the main carbon sources, and the yield can be significantly increased by optimizing fermentation conditions (such as carbon-nitrogen ratio, temperature, inoculum size, etc.). Due to its excellent emulsifying, wetting, and foaming properties, sophorolipid has been widely used in the fields of food, cosmetics, medicine, and environmental protection. Especially in soil improvement and plant growth promotion, sophorolipid performs particularly outstandingly, being able to improve soil structure, enhance plant nutrient absorption, and improve stress resistance, thus providing a more environmentally friendly and effective solution for the sustainable development of agriculture and ecology.

[0005] The PHBV bioactive preparation is a fermentation liquid made from starch or glucose as raw materials. After producing PHBV biodegradable material (i.e., PHBV bioactive preparation) using fermentation engineering technology, the remaining liquid is neutralized to neutral or acidic with phosphoric acid. The PHBV bioactive preparation is the fermentation broth produced during the production of PHBV, with a PHBV content of approximately 4.66 g / L. It is estimated that about 30 tons of fermentation broth are produced for every 1 ton of PHBV produced. In addition, PHBV can be produced by microorganisms under conditions rich in N and P. Therefore, the fermentation broth contains a large amount of nutrients such as C, N, and P, which can be used to improve barren soil and provide nutrients for the growth and development of crops and soil microorganisms. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects in the prior art and provide a composite preparation and method based on sophorolipid and PHBV bioactive preparation.

[0007] The specific technical solutions adopted by the present invention are as follows:

[0008] In the first aspect, the present invention provides a preparation method of a composite preparation based on sophorolipid and PHBV bioactive preparation, which is specifically as follows:

[0009] Dissolve and mix sophorolipid and PHBV bioactive preparation in water to obtain a composite preparation.

[0010] Preferably, the mass fraction of the sophorolipid is 30%.

[0011] Preferably, the PHBV bioactive preparation is previously neutralized with phosphoric acid to make the pH between 6.5 and 7.3.

[0012] Preferably, in the composite preparation, 1.5 ml of sophorolipid and 11.5 ml of PHBV bioactive preparation are added to every 1 L of water.

[0013] In the second aspect, the present invention provides a composite preparation based on sophorolipid and PHBV bioactive preparation according to any one of the first aspect.

[0014] In the third aspect, the present invention provides a method for promoting the growth of sunflower crops in saline-alkali soil, which is specifically as follows:

[0015] Before planting crops, irrigate the saline-alkali soil where sunflower crops need to be planted with the composite preparation based on sophorolipid and PHBV bioactive preparation as described in the second aspect; under the synergistic effect of sophorolipid and PHBV bioactive preparation, it can improve the physical and chemical properties of saline-alkali soil, promote plant growth and development, and improve the stress resistance of sunflower crops.

[0016] Preferably, the application amount of the composite preparation is 60 - 80 L / mu.

[0017] The present invention has the following beneficial effects compared with the prior art:

[0018] By means of a composite preparation containing sophorolipid and PHBV bioactive preparation, it aims to effectively improve the growth indexes of plants (such as plant height, plant diameter, fresh weight, dry weight, number of leaves, flower disk diameter, etc.), and at the same time increase the grain yield, so as to overcome the limitation that the prior art has limited effects on plant growth and yield improvement during the improvement of saline-alkali land. Description of the Drawings

[0019] Figure 1 For the change of plant height of sunflower plants at each stage in Example 2;

[0020] Figure 2 For the change of plant diameter of sunflower plants at each stage in Example 2;

[0021] Figure 3 For the fresh weight (a), dry weight (b), number of leaves (c), and flower disk diameter (d) of sunflower in Example 2;

[0022] Figure 4 For the total weight of sunflower seeds in Example 2. Detailed Embodiments

[0023] The present invention will be further described and explained below in conjunction with the drawings and detailed embodiments. Without conflict, the technical features of each embodiment in the present invention can be combined accordingly.

[0024] The present invention provides a preparation method of a composite preparation based on sophorolipid and PHBV bioactive preparation, and the specific preparation method is as follows:

[0025] Dissolve sophorolipid and PHBV bioactive preparation in water and mix the two evenly to obtain a composite preparation.

[0026] As a preferred embodiment of the present invention, the mass fraction of sophorolipid is 30%; the PHBV bioactive preparation is neutralized by phosphoric acid in advance to make the pH between 6.5 and 7.3.

[0027] As a preferred embodiment of the present invention, in the composite preparation, 1.5 ml of sophorolipid and 11.5 ml of PHBV bioactive preparation are added to each 1 L of water.

[0028] The composite preparation prepared by using the present invention can be irrigated into the saline-alkali soil where sunflower crops need to be planted; under the synergistic action of sophorolipid and PHBV bioactive preparation, it can improve the physical and chemical properties of saline-alkali soil, promote plant growth and development, and improve the stress resistance of sunflower crops.

[0029] Specifically, the composite preparation can improve the soil environment and promote plant growth in the following ways:

[0030] 1) Improve the physical and chemical properties of the soil: Sophorolipid and PHBV bioactive preparation can significantly improve the physical structure of saline-alkali soil, enhance the water and fertilizer retention capacity of the soil, reduce the salt concentration, and improve the root environment, thus providing more favorable conditions for plant growth.

[0031] 2) Promote plant growth and development: Through the combination of sophorolipid and PHBV bioactive preparation, the composite preparation can significantly increase the plant height, fresh weight, dry weight, flower disk diameter and grain yield of sunflower crops. As a surfactant, sophorolipid can enhance the absorption of nutrients by sunflower crops and stimulate the development of sunflower crop roots; while the PHBV bioactive preparation can slowly release nutrients and effectively support the growth of sunflower crops in the long term.

[0032] 3) Improve plant stress resistance: The composite preparation can enhance the stress resistance of sunflower crops in saline-alkali environments, enabling sunflower crops to maintain good growth under higher saline-alkali conditions and reducing the phenomenon of growth stagnation or yield reduction caused by saline-alkali stress.

[0033] As a preferred embodiment of the present invention, the application amount of the composite preparation is 60 - 80 L / mu.

[0034] The composite preparation provided by the present invention can effectively improve the growth indexes of plants within a certain period of time. As shown by multiple experimental comparisons (WCK control group, HZF sophorolipid group, 40HZF sophorolipid + PHBV group), the composite preparation significantly improves the growth indexes such as plant height, plant diameter, fresh weight, dry weight, number of leaves and flower disk diameter of plants, and achieves a significant yield increase in the total grain weight. This indicates that the present invention can be well applied to the improvement of saline-alkali land and promote the increase of crop yield.

[0035] This technical solution not only has significant application value in improving saline-alkali soil, but also can be applied to other farming systems that need to improve the soil environment, and has broad popularization prospects.

[0036] The present invention will be further described below with reference to the embodiments.

[0037] Example 1

[0038] In this example, a composite preparation based on sophorolipid and PHBV bioactive preparation was prepared. The preparation method of the composite preparation is as follows:

[0039] Dissolve 1.5 ml of sophorolipid (mass fraction 30%) and 11.5 ml of PHBV bioactive preparation neutralized with phosphoric acid in 1 L of water, and stir and mix evenly with a glass rod to obtain the composite preparation.

[0040] Example 2

[0041] The soil from Nannong Village, Dingji Town, Huaiyin District, Huai'an City, Jiangsu Province (33.67695°N, 118.97245°E) collected was air-dried, and impurities such as visible roots and stones were removed. After grinding through a 2-mm sieve, it was homogenized. The pH of the soil was 9.84 ± 0.03, and the electrical conductivity was 253.33 ± 10.76 μs / cm. The experiment had 3 levels and 4 replicates; after adding 2 kg of soil to each flowerpot, the corresponding amounts of PHBV biological active agent and sophorolipid were added to the containers, denoted as WCK, HZF, and 40HZF respectively (as shown in Table 1). The moisture was maintained at 60% of the maximum water-holding capacity, and pre-cultured for 1 week to activate the original microorganisms in the soil. The sunflower seeds were disinfected with hydrogen peroxide for 30 min, germinated and then sown. The light intensity was 12000 lux, and the light duration was 10 h / day. The plants were weighed and watered every day. The cultivation period was 80 days. 100 ml of Hoagland nutrient solution was watered every week during the seedling stage of sunflower, and it was changed to 200 ml of Hoagland nutrient solution every week after the budding stage to meet the nutritional requirements for plant growth.

[0042] Table 1 Specific experimental scheme

[0043]

[0044] 1. During the experiment, the plant height of the plants was measured with a tape measure, the plant diameter was measured with a vernier caliper, and the chlorophyll content was measured with a chlorophyll meter. The measurements were carried out at the seedling stage (20 days), budding stage (40 days), flowering stage (60 days), and fruiting stage (80 days) of sunflower respectively.

[0045] The measurement results of the plant height, plant diameter, and chlorophyll content of sunflower were as follows:

[0046] As Figure 1 shown, at 60 days and 80 days of the sunflower crop, the plant height of the control group (WCK) was significantly lower than that of the experimental groups, while the plant height of the sophorolipid (HZF) and sophorolipid + PHBV biological active agent (40HZF) treatment groups increased significantly. The 40HZF treatment group was slightly higher than the HZF group. This indicates that the use of sophorolipid alone or in combination with PHBV biological active agent has a significant promoting effect on plant height, especially at 60 days and 80 days. At the same time, the plant height of the 40HZF treatment group was slightly higher than that of the HZF group, indicating that the effect is better by applying the composite preparation.

[0047] As Figure 2As shown in the figure, at 20 days, the plant diameter of the group treated with sophorolipids + PHBV bioactive preparations had a significant advantage, indicating that the combined treatment of sophorolipids and PHBV bioactive preparations had a positive effect on the plant diameter in the early stages. However, at the following 40 days, 60 days, and 80 days, there were no significant differences in the plant diameters of the three groups of treatments, which may indicate that the early effects of the treatments gradually converged in the later stages, or that the plant diameter was greatly affected by other factors in the later stages. In summary, these results may suggest that the combination of sophorolipids and PHBV bioactive preparations has a promoting effect on the plant diameter in the early stages.

[0048] 2. During the experiment, 80 days after the plants were treated, the above-ground parts were weighed; the diameter of the sunflower disk was measured with a vernier caliper; the length and width of the leaves were measured with a ruler, and the number of sunflower leaves was recorded.

[0049] The results of the determination of the fresh weight, dry weight, disk diameter, number of leaves, and leaf width-to-length ratio of oil sunflower are as follows:

[0050] like Figure 3 As shown, sophorolipid treatment (whether combined with PHBV bioactive agent or not) significantly promoted the fresh weight, dry weight and disk diameter of oil sunflower, but had little effect on the leaf number.

[0051] 3. Cut off the flower disk of the oil sunflower, dry it to constant weight, sow the seeds in the flower disk and weigh the total weight of the seeds with a balance, and record the weight of 100 seeds.

[0052] The results of the determination of 100-grain weight and total weight of oil sunflower seeds are as follows:

[0053] like Figure 4 As shown in the figure, the combined treatment of sophorolipids and PHBV bioactive preparations has a significant promoting effect on the total weight of sunflower seeds. Although sophorolipids alone have a certain promoting effect on the total weight of seeds, the effect is not as good as the combination with PHBV bioactive preparations.

[0054] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A method for preparing a composite preparation based on sophorolipids and PHBV bioactive preparations, characterized in that: The details are as follows: Sophorolipids and PHBV bioactive preparations are dissolved in water and mixed evenly to obtain a composite preparation.

2. The method for preparing a composite preparation based on a sophorolipid and a PHBV bioactive agent according to claim 1, characterized in that: The mass fraction of the sophorolipid is 30%.

3. The method for preparing a composite preparation based on a sophorolipid and a PHBV bioactive agent according to claim 1, characterized in that: The PHBV biologically active preparation is neutralized with phosphoric acid in advance to make the pH value between 6.5 and 7.

3.

4. The method for preparing a composite preparation based on a sophorolipid and a PHBV bioactive agent according to claim 1, characterized in that: In the composite preparation, 1.5 ml of sophorolipid and 11.5 ml of PHBV bioactive preparation were added to every 1 L of water.

5. A composite preparation using the bioactive preparation based on sophorolipid and PHBV according to any one of claims 1 to 4.

6. A method for improving the growth of oil sunflower crops in saline-alkali soil, characterized in that: The details are as follows: The composite preparation based on sophorolipid and PHBV bioactive agent as claimed in claim 5 is irrigated into the saline-alkali soil where oil sunflower crops need to be planted; under the synergistic effect of sophorolipid and PHBV bioactive agent, the physical and chemical properties of saline-alkali soil can be improved, plant growth and development can be promoted, and the stress resistance of oil sunflower crops can be improved.

7. The method according to claim 6, characterized in that The application amount of the composite preparation is 60 to 80 L / mu.

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