Application of molybdenum-regulated synergistic substance phlorizin in promoting crop growth and activating soil phosphorus

Abstract

The invention provides an application of a molybdenum-regulated synergistic substance phlorizin in promoting crop growth and activating soil phosphorus, and systematically studies the influence of externally applied phlorizin on soybean growth and the form and content of phosphorus in soil. The difference between an experimental group and a control group is compared, the effect of phlorizin on promoting soybean growth and promoting transformation of soil phosphorus is disclosed, meanwhile, the application of phlorizin remarkably promotes soybean growth, and particularly, the application of phlorizin is embodied in the aspects of increase of soybean plant height, improvement of dry matter quality of overground parts and roots and the like. Therefore, the invention not only provides a brand new growth promotion strategy for soybean production, but also opens up an effective way for improving the utilization rate of phosphorus in soil and improving the overall quality of the soil.

Description

Technical Field

[0001] The invention relates to the field of agricultural planting, and in particular to application of phlorizin, a molybdenum-regulated synergistic substance, in promoting crop growth and activating soil phosphorus. Background Art

[0002] Phosphorus is an indispensable nutrient for plant growth and plays a key role in plant growth, development and yield formation. However, most of the phosphorus in the soil exists in a form that is difficult for plants to directly absorb and utilize, resulting in a low utilization rate of phosphorus. In order to improve the utilization efficiency of phosphorus, researchers have been exploring various strategies, including the use of exogenous substances to enhance the absorption and utilization ability of plants to phosphorus.

[0003] As a naturally occurring plant secondary metabolite, flavonoids play an important role in the activation of soil phosphorus. Through metal chelation, flavonoids can convert insoluble phosphorus in the soil into a form that can be used by plants. In addition, as part of root exudates, flavonoids can not only promote the release of nutrients and increase their availability, but also indirectly promote phosphorus activation by changing the community structure of rhizosphere microorganisms and reducing the consumption of organic matter. These mechanisms together reveal the key role of flavonoids in soil phosphorus cycling and plant nutrient absorption. In recent years, studies have shown that phosphorus-deficient environments induce plant roots to secrete more flavonoid compounds. For example, under phosphorus-deficient conditions, the accumulation of flavonoid compounds in the roots of white lupin promoted the formation of cluster roots through exogenous addition of flavonoids, alleviating the deficiency of soil phosphorus. Further studies have found that the application of molybdenum can significantly regulate the changes in metabolites in the rhizosphere soil of soybeans, affect the morphological transformation of soil phosphorus, and improve the effectiveness of phosphorus. One of the important metabolites is phlorizin.

[0004] Phlorizin is a natural flavonoid compound with multiple biological activities, which has been found to have positive effects on plant growth in recent years. However, the application of phlorizin on soybean growth and phosphorus absorption has not been studied yet. Summary of the invention

[0005] In view of the above problems, the present invention provides an application of a molybdenum-regulated synergistic substance, phlorizin, in promoting crop growth and activating soil phosphorus, and studies the effect of exogenous application of phlorizin on soybean growth, as well as on the form and content of phosphorus in the soil. By comparing the differences between the experimental group and the control group, the role of phlorizin in promoting soybean growth and promoting the transformation of soil phosphorus is revealed.

[0006] A molybdenum-regulated synergistic substance phlorizin is used in promoting crop growth and activating soil phosphorus, wherein the synergistic substance comprises phlorizin, and the synergistic substance is used for the following purposes:

[0007] Increase the aboveground dry matter mass, root dry matter mass and plant height of crops;

[0008] Increase the phosphorus content and phosphorus accumulation in the aboveground and roots.

[0009] The soil phosphorus activator is used for the following purpose: increasing the content of unstable inorganic phosphorus, unstable organic phosphorus and medium-stable organic phosphorus in the soil.

[0010] The crops are selected from soybeans.

[0011] The synergistic substance contains phlorizin, and the concentration of phlorizin in the solution is 1-10 μmol / L.

[0012] Preferably, the concentration of phlorizin in the solution is 5 μmol / L or 10 μmol / L.

[0013] The solution contains phosphorus nutrients and molybdenum nutrients.

[0014] The molybdenum nutrient is (NH4)6Mo7O 24 ·4H2O.

[0015] The concentration of the molybdenum nutrient in the solution is 0.02 μM.

[0016] The present invention provides an application of phlorizin in the preparation of a soybean growth promoting additive, and studies the effect of exogenous application of phlorizin on soybean growth, as well as on the form and content of phosphorus in soil. By comparing the differences between the experimental group and the control group, the effect of phlorizin on promoting soybean growth and promoting the conversion of soil phosphorus is revealed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 To study the effect of molybdenum application on phosphorus absorption and translocation in soybean under different phosphorus levels.

[0018] Figure 2 The number of metabolites with significant changes mediated by Mo under Control treatment;

[0019] Figure 3 is the number of metabolites with significant changes mediated by Mo under P treatment;

[0020] Figure 4 The 50 differential metabolites mediated by Mo under Control treatment;

[0021] Figure 5 There are 94 different metabolites mediated by Mo under P treatment;

[0022] Figure 6 The flavonoids whose abundance changed significantly under different phosphorus levels mediated by molybdenum application;

[0023] Figure 7 The phenotypic photos of soybean growth affected by different concentrations of phlorizin;

[0024] Figure 8 The effects of different concentrations of phlorizin on soybean plant height, aboveground dry matter mass and root dry matter mass under hydroponic conditions;

[0025] Fig. 9 The effects of phlorizin and Mo treatments on soil available phosphorus content;

[0026] Fig.10 The effects of phlorizin and Mo treatments on soybean plant height, aboveground dry matter mass and root dry matter mass under soil experimental conditions;

[0027] Fig.11 This is the effect of phlorizin and Mo treatments on the phosphorus content and phosphorus accumulation in the aboveground parts and roots of soybean under soil experimental conditions. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific implementation methods. It should be understood that the specific implementation methods described here are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0029] Example 1: Effect of molybdenum application on soybean phosphorus absorption

[0030] The experiment set up two phosphorus addition levels: 0.015g / kg (to ensure normal growth of crops in the early stage), represented by Control; 0.15g / kg, represented by P. Two molybdenum addition levels: 0mg / kg, represented by -Mo; 0.15mg / kg, represented by +Mo. There were 4 treatments in total, namely Control-Mo, Control+Mo, P-Mo, and P+Mo. Each treatment was repeated 4 times, with a total of 16 pots. The soybean variety for the test was Tianlong No. 1. The soil was placed in the inner and outer chambers of the root box at the same time and compacted. The soybean seeds were sown in the inner chamber for growth. Each barrel, including the root box, was filled with 8.0kg of soil.

[0031] like Figure 1 As shown in the figure, after comparative analysis, when the molybdenum addition level was the same, phosphorus treatment significantly increased the aboveground phosphorus content, phosphorus transport coefficient, aboveground phosphorus accumulation, root phosphorus accumulation and overall phosphorus accumulation of soybean, but had no significant effect on the root phosphorus content. On the other hand, when the phosphorus level was the same, compared with the non-molybdenum treatment, the molybdenum treatment not only significantly increased the aboveground phosphorus content, phosphorus transport coefficient and aboveground and whole plant phosphorus accumulation of soybean, but also significantly reduced the root phosphorus content and accumulation of soybean under the two phosphorus levels. This shows that molybdenum application can effectively improve the phosphorus absorption efficiency of soybean at different phosphorus levels, and promote the transport of root phosphorus to the aboveground part, thereby increasing the aboveground phosphorus accumulation and reducing the root phosphorus accumulation.

[0032] Example 2: Effect of molybdenum application on soybean rhizosphere metabolites

[0033] Since molybdenum application can significantly promote the increase of available phosphorus content in soil, metabolomics methods can be used to systematically screen substances whose metabolite abundance in soybean roots changes significantly under molybdenum application treatment.

[0034] Figure 2 to Figure 5 We identified 584 metabolites after exhaustive analysis in both positive and negative ion modes. Figure 2 and Figure 4 In the experiment, under the treatment condition of Control phosphorus addition level, the effect of molybdenum application on metabolites was significant. After molybdenum application, the abundance of 19 metabolites showed an upward trend, the abundance of 31 metabolites decreased, and the abundance of the remaining 534 metabolites did not change significantly. Figure 3 and Figure 5 Among the metabolites affected by molybdenum application under P treatment, the abundance of 33 metabolites increased significantly after molybdenum application, while the abundance of 61 metabolites decreased significantly. Further KEGG pathway enrichment analysis showed that under P+Mo treatment, the differential metabolites were mainly enriched in four key metabolic pathways, including flavonoid biosynthesis, phenylpropanoid biosynthesis, caprolactam degradation, and carbohydrate digestion and absorption.

[0035] Figure 6 In the treatment condition with phosphorus addition level of P, the enrichment of differential metabolites was more extensive, and was significantly distributed in 20 metabolic pathways, especially ABC transporters, galactose metabolism, cysteine ​​and methionine metabolism, flavonoid biosynthesis, thermogenesis, carbohydrate digestion and absorption, mineral absorption, and EGFR tyrosine kinase inhibitor resistance. Metabolic pathways showed more significant enrichment. Given that the differential metabolites were significantly enriched in the flavonoid biosynthesis pathway under two different phosphorus levels, we conducted an in-depth analysis of the flavonoid substances that changed differentially under these two phosphorus levels. Under the P treatment, molybdenum application significantly increased the abundance of vigneron, phlorizin, neoastilbin, hesperidin 5-O-glucoside and catechin 7-glucoside. Under the treatment of molybdenum application, the abundance of a flavonoid substance-phlorizin was found to be significantly different after identification, such as Figure 6 As shown, this substance is also more easily absorbed and utilized by organisms and has higher safety, being non-toxic or low-toxic to the human body.

[0036] Example 3: Determination of Phlorizin Concentration

[0037] Phlorizin (Pz) was used to test the growth-promoting effect of soybean. The nutrient solution culture test site was the glass greenhouse of the College of Resources and Environment of Huazhong Agricultural University. The growth conditions were set at 25°C and 14 hours of light. The plastic box was used as the culture container. The specifications of the plastic box were 30.3×20.5×8.5cm. The plastic box and the foam board cover were opaque. Each pot contained 3L of nutrient solution. The nutrient solution formula was 4mM Ca(NO3)2·4H2O, 1mM NH4NO3, 1mM KH2PO4, 5mM KNO3, 2mM MgSO4·7H2O, 9.55μM MnSO4·4H2O, 46.28μM H3BO3, 0.77μM ZnSO4·7H2O, 0.32μM CuSO4·5H2O, 0.02μM (NH4)6Mo7O 24 4H2O, 98.09μM EDTA-Fe, the nutrient solution was changed every 4 days.

[0038] Phlorizin was dissolved in 0.5mL 80% methanol and added to the nutrient solution. The concentration of phlorizin in the nutrient solution was set to 0μmol / L, 0.5μmol / L, 1μmol / L, 2μmol / L, 5μmol / L, and 10μmol / L. The same amount of 80% methanol was added to the control treatment, and each treatment was repeated 3 times. Soybeans were harvested after 30 days of growth, and the dry matter weight and phosphorus content of the plants were determined. Soybean seeds with complete seed coat and full grains were selected. After being disinfected by soaking in 2% sodium hypochlorite solution for 15 minutes, they were cleaned with ultrapure water and soaked for 3 hours to allow the soybeans to fully absorb water and expose the embryos. Then, they were evenly sown in vermiculite for seedling cultivation. After 4 days, they grew to about 5cm in height and were transplanted when the cotyledons were unfolded. Soybean seedlings with consistent growth were selected, and 6 soybeans were planted in each pot. Sponges were used to clamp the soybeans to prevent them from sliding down. Soybeans were harvested after 30 days of growth.

[0039] Soybean phenotypic indicators and photosynthetic parameters were measured: (1) Plant height: The height of the main stem of soybean was measured with a tape measure at harvest time; (2) Dry weight: The samples of various parts of soybean were sterilized at 105°C for 30 minutes, and the dry weight was recorded after being dried at 60°C to constant weight; (3) Photosynthetic parameters: Net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, and transpiration rate were measured using a portable photosynthetic meter (LICOR-6400XT) between 8 and 11 am on a clear day. (4) Determination of plant phosphorus content: Weigh the plant sample, put 0.1500g into a 50ml digestion tube, add 5ml of concentrated sulfuric acid, let it stand overnight, and then preheat it at 160°C in an infrared digestion furnace for 10-15 minutes, then raise the temperature to 280°C, take it out and cool it slightly, then add a small amount of 30% H2O2 and repeat several times until the digestion liquid becomes clear, and then use a flow analyzer to determine the phosphorus content after constant volume filtration.

[0040] like Figure 7-8As shown in the figure, after comparative analysis, the soybean growth phenotype under the treatment of pz concentration of 5μmol / L and 10μmol / L was the best, significantly better than other concentrations. Specifically, the aboveground dry matter mass, root dry matter mass and plant height of the treatments with pz concentrations of 5μmol / L and 10μmol / L were significantly higher than those of other treatments, but there was no significant difference between the treatments with pz concentrations of 5μmol / L and 10μmol / L. It can be seen that when the Pz concentration is 5μmol / kg and 10μmol / kg, the growth-promoting effect on soybean is the best. In order to further control costs, this study used 5μmol / kg phlorizin for the next verification experiment.

[0041] Example 4: Phlorizin

[0042] Step 1: Experimental treatment setup

[0043] Control group (CK): only ultrapure water was added; Pz: only 5 μmol / kg phlorizin was added.

[0044] Step 2: Add fertilizer

[0045] The following levels of fertilizer were added to each test pot:

[0046] Nitrogen: added in the form of urea ((NH2)2CO) at a level of 0.15 g / kg; Phosphorus: added in the form of potassium dihydrogen phosphate (KH2PO4) at a level of 0.15 g / kg; Potassium: added in the form of potassium chloride (KCl) at a level of 0.20 g / kg.

[0047] Step 3: Addition of Mo and phlorizin

[0048] Mo to (NH4)6Mo7O 24 4H2O was added to the soil as a molybdenum source; and phlorizin was dissolved in 80% methanol and then added to the soil of the experimental group. The same amount of 80% methanol was added to the control group, but phlorizin was not added.

[0049] Step 4: Soybean Seed Processing and Planting

[0050] Select soybean seeds with intact seed coat and full grains, soak them in 2% sodium hypochlorite solution for 15 minutes for disinfection, and then clean them with ultrapure water. Then, soak the seeds for 3 hours to allow them to fully absorb water and expose the embryo. After that, evenly sow the seeds in vermiculite for seedling cultivation.

[0051] Step 5: Transplanting and growing conditions

[0052] After 4 days of seedling raising, when the soybean seedlings grow to about 5 cm in height and the cotyledons are unfolded, transplant the seedlings. Select soybean seedlings with consistent growth, clean their roots, and transplant one per pot. The experiment was conducted in a glass greenhouse at the College of Resources and Environment of Huazhong Agricultural University, with growth conditions set at 25°C and 14 hours of light.

[0053] Step 6: Sample measurement.

[0054] The soybeans were harvested after 45 days of growth and then tested. The test results are shown in Table 1 and Figure 9-11 As shown in the results, compared with the control group CK, under the Pz treatment, the contents of labile inorganic phosphorus, labile organic phosphorus, and medium-stable organic phosphorus in the soil all increased significantly, while the content of stable phosphorus decreased significantly. At the same time, the content of medium-stable inorganic phosphorus remained stable. This result shows that phlorizin can effectively promote the transformation of rhizosphere phosphorus from a stable state to an unstable state, thereby contributing to the absorption and utilization of phosphorus by crops.

[0055] Table 1 Effects of phlorizin treatment on phosphorus forms in soybean rhizosphere soil

[0056]

[0057] like Fig. 9 The results showed that compared with the control group CK treatment, the exogenous addition of phlorizin significantly increased the content of available phosphorus in the soil, with an increase of 13.01%. This data clearly shows that phlorizin treatment helps to promote the release of available phosphorus in the soil, or slow down its fixation and transformation process, thereby effectively improving the utilization rate of available phosphorus in the soil. This result further confirms that the rhizosphere metabolite phlorizin under Mo regulation has the ability to activate soil available phosphorus, thereby promoting soybean absorption and accumulation of phosphorus, and ultimately having a positive effect on soybean growth.

[0058] Fig.10 The results showed that compared with the control group CK, soybeans treated with phlorizin showed significant improvements in plant height, aboveground dry matter mass, and root dry matter mass. Specifically, phlorizin treatment increased plant height by 13.92%, aboveground dry matter mass by 7.98%, and root dry matter mass by 11.67%.

[0059] Depend on Fig.11It can be seen that the soybean plants treated with phlorizin showed a significant increase in the phosphorus content and phosphorus accumulation in the aboveground and roots. Specifically, compared with the control treatment, phlorizin treatment increased the phosphorus content in the aboveground by 24.21% and the phosphorus accumulation by 34.95%; at the same time, the phosphorus content and phosphorus accumulation in the roots also increased by 19.61% and 29.09%, respectively. The results show that the positive role of phlorizin in promoting soybean phosphorus nutrient absorption cannot be ignored. This discovery is of great significance for using phlorizin to improve soybean phosphorus utilization and promote soybean growth.

[0060] The present invention provides an application of phlorizin, a soybean rhizosphere metabolite regulated by molybdenum, in promoting soil phosphorus activation, and systematically studies the effects of exogenous application of phlorizin on soybean growth, the form and content of phosphorus in the soil, and the effects of molybdenum application on phlorizin in soybean root system. By comparing the differences between the experimental group and the control group, the effects of phlorizin in promoting soybean growth and promoting the transformation of soil phosphorus are revealed.

[0061] Please note that the above embodiments are only used to illustrate the present method and do not constitute a limitation on the scope of protection. Various equivalent replacements and modifications can be made to the above embodiments without departing from the spirit and essence of the present method.

[0062] The above examples are for the purpose of illustrating the embodiments disclosed by the present invention and are not to be construed as limiting the present invention. In addition, the various modifications listed herein and the variations of the methods in the invention are obvious to those skilled in the art without departing from the scope and spirit of the present invention. Although the present invention has been specifically described in conjunction with various specific preferred embodiments of the present invention, it should be understood that the present invention should not be limited to these specific embodiments. In fact, various modifications as described above that are obvious to those skilled in the art to obtain the invention should be included within the scope of the present invention.

Claims

1. An application of a molybdenum-regulated synergistic substance phlorizin in promoting crop growth and activating soil phosphorus, wherein the synergistic substance or soil phosphorus activator contains phlorizin, and the synergistic substance is used for the following purposes: Increase the aboveground dry matter mass, root dry matter mass and plant height of crops; Increase the phosphorus content and accumulation in the aboveground and root parts; The soil phosphorus activator is used for the following purpose: increasing the content of unstable inorganic phosphorus, unstable organic phosphorus and medium-stable organic phosphorus in the soil.

2. The use according to claim 1, characterized in that: The crop is selected from soybean.

3. The use according to claim 1, characterized in that: The synergistic substance is a solution containing phlorizin, and the concentration of phlorizin in the solution is 1-10 μmol / L.

4. The use according to claim 3, characterized in that The concentration of phlorizin in the solution is 5 μmol / L or 10 μmol / L.

5. The use according to claim 3, characterized in that The solution contains phosphorus nutrients and molybdenum nutrients.

6. The use according to claim 3, characterized in that The molybdenum nutrient is (NH4)6Mo7O 24 ·4H2O.

7. The use according to claim 6, characterized in that: The concentration of the molybdenum nutrient in the solution is 0.02 μM.

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