Leaf fertilizer for prolonging ornamental period of leaf color of colored-leaf plant

Abstract

The present disclosure relates to the technical field of foliage fertilizers, and particularly relates to a foliage fertilizer for prolonging the ornamental period of leaf color of colorful plants; in 100 parts by weight of the foliage fertilizer, 0.5-1.5 parts by weight of a vitamin B compound, 0.01-0.05 parts by weight of a benzyl amino purine compound, 0.02-0.05 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.3-0.5 parts by weight of rhamnolipid, 0.4-0.8 parts by weight of malic acid, 0.5-1.5 parts by weight of modified polyethylene glycol, and 0.5-1.5 parts by weight of modified cellulose nanocrystal are contained.

Description

Technical Field

[0001] This disclosure relates to the field of foliar fertilizer technology, and in particular to a foliar fertilizer that extends the ornamental period of colorful foliage plants. Background Technology

[0002] Colorful foliage plants, with their leaves displaying red, orange, purple, and other non-green hues during specific seasons, have become a significant attraction for urban gardens and scenic areas in autumn. Taking the Fragrant Hills (Xiangshan) autumn foliage area in Beijing as an example, the main colorful foliage tree species is the smoke tree (Cotinus coggygria), planted during the Qianlong era of the Qing Dynasty. Over the past 200 years, the total number of these trees has grown to nearly 100,000, covering an area of ​​approximately 1,400 acres. Every year during the Fragrant Hills Autumn Foliage Festival, it attracts millions of tourists from Beijing and surrounding areas. In recent years, however, due to abnormal climate, increased extreme weather, longer warm periods, smaller diurnal temperature ranges, longer hours of sunshine, and persistent strong winds, the color change of the smoke trees has become unstable. Often, some leaves fall off before fully changing color, severely reducing the quality of the autumn foliage landscape. This situation is not unique to Fragrant Hills in Beijing but has occurred in many other regions.

[0003] Therefore, there is an urgent need to develop a foliar fertilizer that can be used to extend the period of leaf color appreciation in colorful foliage plants. Summary of the Invention

[0004] This disclosure provides a foliar fertilizer that extends the ornamental period of colorful foliage plants, thereby addressing the shortcomings of related technologies.

[0005] According to a first aspect of the present disclosure, a foliar fertilizer is provided to extend the ornamental period of colorful foliage plants, the foliar fertilizer comprising the following components: B vitamins, benzylaminopurine compounds, ethylenediaminetetraacetic acid chelated titanium, rhamnolipids, soluble sugars, amino acids, and malic acid.

[0006] In one aspect of this disclosure, the foliar fertilizer further comprises the following components: modified polyethylene glycol and modified cellulose nanocrystals.

[0007] In one aspect of this disclosure, the modified polyethylene glycol is an aminated polyethylene glycol.

[0008] In one aspect of this disclosure, the modified cellulose nanocrystals are selected from quaternized modified cellulose nanocrystals.

[0009] In one aspect of this disclosure, the soluble sugar comprises at least one monosaccharide, disaccharide, or oligosaccharide; and at least one sugar alcohol. The monosaccharide may be selected from glucose, fructose, or galactose; the disaccharide may be selected from sucrose, lactose, or maltose; the oligosaccharide may be selected from chitosan oligosaccharides, cellooligosaccharides, or xylooligosaccharides; and the sugar alcohol may be selected from sorbitol, mannitol, xylitol, arabinitol, maltitol, lactitol, or galactitol.

[0010] In one aspect of this disclosure, the soluble sugar comprises glucose and mannitol; the mass ratio of glucose to mannitol is selected from 1:(2-4).

[0011] In one aspect of this disclosure, the amino acid is selected from at least one of glycine, alanine, glutamic acid, aspartic acid, and lysine.

[0012] In one aspect of this disclosure, the aminated polyethylene glycol is prepared by the following steps: Step 1-a: Dissolve polyethylene glycol in dichloromethane, then add p-toluenesulfonyl chloride and potassium hydroxide; stir for 24-48 hours; then wash and separate the contents. Step 2-a: Dissolve the product obtained in step 1-a in dichloromethane, and after drying, ether precipitation, and vacuum drying, obtain the intermediate product; Step 3-a: Dissolve the intermediate product obtained in step 2-a in ammonia water, then add ammonium chloride, and react at room temperature for 48-72 hours; Step 4-a: Add sodium chloride to the product obtained in step 3-a, then extract with dichloromethane, and after drying, ether precipitation, and vacuum drying, obtain the aminated modified polyethylene glycol.

[0013] In one aspect of this disclosure, the quaternized cellulose nanocrystals are prepared by the following steps: Step 1-b: Prepare cellulose nanocrystals and obtain an aqueous suspension of cellulose nanocrystals; Step 2-b: Add sodium hydroxide to the aqueous suspension of cellulose nanocrystals obtained in Step 1-b and stir at room temperature for 20-60 min; then add 2,3-epoxypropyltrimethylammonium chloride and react at 55℃-65℃ for 3-6 h under nitrogen protection. Step 3-b: After the reaction is complete, cool to room temperature, and obtain the quaternized ammonium modified cellulose nanocrystals after acetone precipitation, washing, and drying.

[0014] In one aspect of this disclosure, the cellulose nanocrystals are prepared by the following steps: Step 1-c: Provide filter paper fragments; add the filter paper fragments to the reaction vessel; add sulfuric acid solution, and mechanically stir at 40℃-50℃ for 1-2 hours; Step 2-c: After the reaction is complete, add cold water to terminate the reaction; the resulting suspension is purified by centrifugation, washing with water, and dialysis to obtain the cellulose nanocrystals.

[0015] In one aspect of the embodiments of this disclosure, the vitamin B compound is selected from one or more of vitamin B1, vitamin B2, vitamin B3, vitamin B4, vitamin B5, and vitamin B16, or a mixture thereof; the benzylaminopurine compound is selected from 6-benzylaminopurine.

[0016] In one aspect of the embodiments of this disclosure, preferably, the vitamin B complex comprises vitamin B2, vitamin B3, vitamin B4 and vitamin B5; specifically, vitamin B2 accounts for 60% or more of the total mass of the vitamin B complex.

[0017] In one aspect of this disclosure, 100 parts by weight of the foliar fertilizer comprises the following components in parts by weight: 0.5-1.5 parts by weight of B vitamins, 0.01-0.05 parts by weight of benzylaminopurine compounds, 0.02-0.05 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.3-0.5 parts by weight of rhamnolipids, 0.5-1.0 parts by weight of soluble sugars, 0.2-0.3 parts by weight of amino acids, 0.4-0.8 parts by weight of malic acid, 0.5-1.5 parts by weight of modified polyethylene glycol, and 0.5-1.5 parts by weight of modified cellulose nanocrystals.

[0018] In one aspect of the embodiments of this disclosure, the colorful foliage plants are selected from smoke tree, red maple, sugar maple, five-lobed maple, Japanese maple, treasury maple, purple barberry or tulip tree.

[0019] The technical solutions provided by the embodiments of this disclosure may include the following beneficial effects: As can be seen from the above embodiments, this disclosure has prepared a foliar fertilizer that enables the slow-release absorption of vitamin B and benzylaminopurine by the leaves of colorful foliage plants, which can prolong the ornamental period of the leaves of colorful foliage plants.

[0020] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Detailed Implementation

[0021] Exemplary embodiments will now be described in detail. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0022] Exemplary embodiments will now be described in detail. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The embodiments described herein are illustrative in nature and are used to provide a basic understanding of this application. The embodiments of this application should not be construed as limiting this application.

[0024] For the sake of brevity, this article only discloses a few specific numerical ranges. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, just as any upper limit can be combined with any other upper limit to form an unspecified range. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and be combined with any other point or single value or with other lower or upper limits to form an unspecified range.

[0025] In this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0026] In this description, unless otherwise stated, "above" and "below" include the stated number.

[0027] Unless otherwise stated, the terms used in this disclosure have their common meanings as commonly understood by those skilled in the art. Unless otherwise stated, the values ​​of the parameters mentioned in this disclosure can be measured using various measurement methods commonly used in the art (e.g., they can be tested according to the methods given in the embodiments of this disclosure).

[0028] The term "about" is used to describe and indicate small variations. When used in conjunction with an event or situation, the term may refer to examples in which the event or situation occurred precisely or in examples in which the event or situation occurred very approximately. For example, when used in conjunction with numerical values, the term may refer to a range of variation less than or equal to ±10% of the numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. Additionally, quantities, ratios, and other numerical values ​​are sometimes presented in range format herein. It should be understood that such range format is for convenience and brevity and should be interpreted flexibly to include not only numerical values ​​explicitly specified as range limits but also all individual numerical values ​​or subranges covered within the range, as if each numerical value and subrange were explicitly specified.

[0029] The list of items connected by the terms "at least one of," "at least one of," "at least one of," or other similar terms can mean any combination of the listed items. For example, if items A and B are listed, then the phrase "at least one of A and B" means only A; only B; or A and B. In another instance, if items A, B, and C are listed, then the phrase "at least one of A, B, and C" means only A; or only B; only C; A and B (excluding C); A and C (excluding B); B and C (excluding A); or all of A, B, and C. Item A may contain a single component or multiple components. Item B may contain a single component or multiple components. Item C may contain a single component or multiple components.

[0030] The present invention will be further described below by way of specific embodiments. Unless otherwise specified, all chemical reagents used in the embodiments of the present invention were obtained through conventional commercial means. Unless otherwise specified, all contents mentioned below are mass contents. Unless otherwise specified, it is understood that the process was carried out at room temperature.

[0031] Examples and Comparative Examples Example 1: Example 1 includes the following steps: 1. Preparation of aminated modified polyethylene glycol: 120 g of polyethylene glycol (PEG600, all polyethylene glycols used in the following examples and comparative examples are PEG600) was dissolved in 400 mL of dichloromethane, and then 57.6 g of p-toluenesulfonyl chloride and 16.8 g of potassium hydroxide were added. After stirring for 36 h, the product was washed with distilled water and separated. The product was then added back to 250 mL of dichloromethane and dried with MgSO4 for 8 h. After precipitation with diethyl ether, the product was dried under vacuum for 12 h to obtain the intermediate product CH3-Ph-SO2-PEG-SO2-Ph-CH3. The intermediate product was dissolved in 800 mL of 25% ammonia water, and then 50 g of ammonium chloride was added. The product was reacted at room temperature for 56 h. Then 400 g of NaCl was added, and the product was extracted with dichloromethane, dried with MgSO4 for 8 h, precipitated with diethyl ether, and dried under vacuum for 12 h to obtain the aminated modified polyethylene glycol (NH2-PEG-NH2) of Example 1.

[0032] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0033] 2. Preparation of quaternized ammonium modified cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain the cellulose nanocrystals of Example 1.

[0034] All cellulose nanocrystals were added to 250 mL of water and stirred to obtain an aqueous suspension of cellulose nanocrystals. Sodium hydroxide was then added to adjust the pH to 12.5. The mixture was stirred at room temperature for 45 min. Then 7.6 g of 2,3-epoxypropyltrimethylammonium chloride was added, and the mixture was reacted at 60 °C for 5 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, precipitated with acetone, washed three times with circulating water, and dried at 60 °C to obtain the quaternized ammonium modified cellulose nanocrystals of Example 1.

[0035] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0036] 3. Preparation of foliar fertilizer: 1.2 parts by weight of aminated polyethylene glycol, 1.2 parts by weight of quaternized cellulose nanocrystals, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were sequentially added to water and stirred until homogeneous to obtain 100 parts by weight of the foliar fertilizer of Example 1.

[0037] Comparative Example 1: Comparative Example 1 includes the following steps: 1. Preparation of aminated modified polyethylene glycol: 120 g of polyethylene glycol was dissolved in 400 mL of dichloromethane, then 57.6 g of p-toluenesulfonyl chloride and 16.8 g of potassium hydroxide were added; the mixture was stirred for 36 h; after washing with distilled water and separation, the product was added back into 250 mL of dichloromethane and dried with MgSO4 for 8 h; after precipitation with diethyl ether, the product was dried under vacuum for 12 h to obtain the intermediate CH3-Ph-SO2-PEG-SO2-Ph-CH3; the intermediate was dissolved in 800 mL of 25% ammonia water, then 50 g of ammonium chloride was added, and the mixture was reacted at room temperature for 56 h; then 400 g of NaCl was added, and the mixture was extracted with dichloromethane, dried with MgSO4 for 8 h, precipitated with diethyl ether, and dried under vacuum for 12 h to obtain the aminated polyethylene glycol (NH2-PEG-NH2) of Comparative Example 1.

[0038] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0039] 2. Preparation of quaternized ammonium modified cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain cellulose nanocrystals of Comparative Example 1.

[0040] All cellulose nanocrystals were added to 250 mL of water and stirred to obtain an aqueous suspension of cellulose nanocrystals. Sodium hydroxide was then added to adjust the pH to 12.5. The mixture was stirred at room temperature for 45 min. Then 7.6 g of 2,3-epoxypropyltrimethylammonium chloride was added, and the mixture was reacted at 60 °C for 5 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, precipitated with acetone, washed three times with circulating water, and dried at 60 °C to obtain the quaternized modified cellulose nanocrystals of Comparative Example 1.

[0041] 3. Preparation of foliar fertilizer: 1.2 parts by weight of aminated polyethylene glycol, 1.2 parts by weight of quaternized cellulose nanocrystals, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were added to water in sequence and stirred until well mixed to obtain 100 parts by weight of the foliar fertilizer of Comparative Example 1.

[0042] The difference between Comparative Example 1 and Example 1 is that the foliar fertilizer in Comparative Example 1 does not contain benzylaminopurine.

[0043] Comparative Example 2: Comparative Example 2 includes the following steps: 1. Preparation of aminated modified polyethylene glycol: 120 g of polyethylene glycol was dissolved in 400 mL of dichloromethane, then 57.6 g of p-toluenesulfonyl chloride and 16.8 g of potassium hydroxide were added; the mixture was stirred for 36 h; after washing with distilled water and separation, the product was added back into 250 mL of dichloromethane and dried with MgSO4 for 8 h; after precipitation with diethyl ether, the product was dried under vacuum for 12 h to obtain the intermediate CH3-Ph-SO2-PEG-SO2-Ph-CH3; the intermediate was dissolved in 800 mL of 25% ammonia water, then 50 g of ammonium chloride was added, and the mixture was reacted at room temperature for 56 h; then 400 g of NaCl was added, and the mixture was extracted with dichloromethane, dried with MgSO4 for 8 h, precipitated with diethyl ether, and dried under vacuum for 12 h to obtain the aminated polyethylene glycol (NH2-PEG-NH2) of Comparative Example 2.

[0044] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0045] 2. Preparation of quaternized ammonium modified cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain the cellulose nanocrystals of Comparative Example 2.

[0046] All cellulose nanocrystals were added to 250 mL of water and stirred to obtain an aqueous suspension of cellulose nanocrystals. Sodium hydroxide was then added to adjust the pH to 12.5. The mixture was stirred at room temperature for 45 min. Then 7.6 g of 2,3-epoxypropyltrimethylammonium chloride was added, and the mixture was reacted at 60 °C for 5 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, precipitated with acetone, washed three times with circulating water, and dried at 60 °C to obtain the quaternized modified cellulose nanocrystals of Comparative Example 2.

[0047] 3. Preparation of foliar fertilizer: 1.2 parts by weight of aminated polyethylene glycol, 1.2 parts by weight of quaternized cellulose nanocrystals, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were added to water in sequence and stirred until well mixed to obtain 100 parts by weight of foliar fertilizer of Comparative Example 2.

[0048] The difference between Comparative Example 2 and Example 1 is that the foliar fertilizer of Comparative Example 2 does not contain vitamin B and benzylaminopurine.

[0049] Comparative Example 3: Comparative Example 3 includes the following steps: 1. Preparation of aminated modified polyethylene glycol: 120 g of polyethylene glycol was dissolved in 400 mL of dichloromethane, then 57.6 g of p-toluenesulfonyl chloride and 16.8 g of potassium hydroxide were added; the mixture was stirred for 36 h; after washing with distilled water and separation, the product was added back into 250 mL of dichloromethane and dried with MgSO4 for 8 h; after precipitation with diethyl ether, the product was dried under vacuum for 12 h to obtain the intermediate CH3-Ph-SO2-PEG-SO2-Ph-CH3; the intermediate was dissolved in 800 mL of 25% ammonia water, then 50 g of ammonium chloride was added, and the mixture was reacted at room temperature for 56 h; then 400 g of NaCl was added, and the mixture was extracted with dichloromethane, dried with MgSO4 for 8 h, precipitated with diethyl ether, and dried under vacuum for 12 h to obtain the aminated polyethylene glycol (NH2-PEG-NH2) of Comparative Example 3.

[0050] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0051] 2. Preparation of quaternized ammonium modified cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain the cellulose nanocrystals of Comparative Example 3.

[0052] All cellulose nanocrystals were added to 250 mL of water and stirred to obtain an aqueous suspension of cellulose nanocrystals. Sodium hydroxide was then added to adjust the pH to 12.5. The mixture was stirred at room temperature for 45 min. Then 7.6 g of 2,3-epoxypropyltrimethylammonium chloride was added, and the mixture was reacted at 60 °C for 5 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, precipitated with acetone, washed three times with circulating water, and dried at 60 °C to obtain the quaternized modified cellulose nanocrystals of Comparative Example 3.

[0053] 3. Preparation of foliar fertilizer: 1.2 parts by weight of aminated polyethylene glycol, 1.2 parts by weight of quaternized cellulose nanocrystals, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were sequentially added to water and stirred until well mixed to obtain 100 parts by weight of the foliar fertilizer of Comparative Example 3.

[0054] The difference between Comparative Example 3 and Example 1 is that the foliar fertilizer in Comparative Example 3 does not contain rhamnolipin.

[0055] Example 2: Example 2 includes the following steps: 1. Preparation of aminated modified polyethylene glycol: 120 g of polyethylene glycol was dissolved in 400 mL of dichloromethane, then 57.6 g of p-toluenesulfonyl chloride and 16.8 g of potassium hydroxide were added; the mixture was stirred for 36 h; after washing with distilled water and separation, the product was added back into 250 mL of dichloromethane and dried with MgSO4 for 8 h; after precipitation with diethyl ether, the product was dried under vacuum for 12 h to obtain the intermediate product CH3-Ph-SO2-PEG-SO2-Ph-CH3; the intermediate product was dissolved in 800 mL of 25% ammonia water, then 50 g of ammonium chloride was added, and the mixture was reacted at room temperature for 56 h; then 400 g of NaCl was added, the mixture was extracted with dichloromethane, dried with MgSO4 for 8 h, precipitated with diethyl ether, and dried under vacuum for 12 h to obtain the aminated modified polyethylene glycol (NH2-PEG-NH2) of Example 2.

[0056] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0057] 2. Preparation of cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain the cellulose nanocrystals of Example 2.

[0058] 3. Preparation of foliar fertilizer: 1.2 parts by weight of aminated polyethylene glycol, 1.2 parts by weight of cellulose nanocrystals, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, and 0.5 parts by weight of malic acid were sequentially added to water and stirred until well mixed to obtain 100 parts by weight of the foliar fertilizer of Example 2.

[0059] The main difference between Example 2 and Example 1 is that the cellulose nanocrystals in Example 2 were not modified by quaternization.

[0060] Example 3: Example 3 includes the following steps: 1. Preparation of aminated modified polyethylene glycol: 120 g of polyethylene glycol was dissolved in 400 mL of dichloromethane, then 57.6 g of p-toluenesulfonyl chloride and 16.8 g of potassium hydroxide were added; the mixture was stirred for 36 h; after washing with distilled water and separation, the product was added back into 250 mL of dichloromethane and dried with MgSO4 for 8 h; after precipitation with diethyl ether, the product was dried under vacuum for 12 h to obtain the intermediate product CH3-Ph-SO2-PEG-SO2-Ph-CH3; the intermediate product was dissolved in 800 mL of 25% ammonia water, then 50 g of ammonium chloride was added, and the mixture was reacted at room temperature for 56 h; then 400 g of NaCl was added, the mixture was extracted with dichloromethane, dried with MgSO4 for 8 h, precipitated with diethyl ether, and dried under vacuum for 12 h to obtain the aminated modified polyethylene glycol (NH2-PEG-NH2) of Example 2.

[0061] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0062] 2. Preparation of foliar fertilizer: 2.4 parts by weight of aminated polyethylene glycol, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were sequentially added to water and stirred until well mixed to obtain 100 parts by weight of the foliar fertilizer of Example 3.

[0063] The main difference between Example 3 and Example 1 is that Example 3 does not contain cellulose nanocrystals.

[0064] Example 4: Example 4 includes the following steps: 1. Preparation of quaternized ammonium modified cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain the cellulose nanocrystals of Example 4.

[0065] All cellulose nanocrystals were added to 250 mL of water and stirred to obtain an aqueous suspension of cellulose nanocrystals. Sodium hydroxide was then added to adjust the pH to 12.5. The mixture was stirred at room temperature for 45 min. Then 7.6 g of 2,3-epoxypropyltrimethylammonium chloride was added, and the mixture was reacted at 60 °C for 5 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, precipitated with acetone, washed three times with circulating water, and dried at 60 °C to obtain the quaternized ammonium modified cellulose nanocrystals of Example 4.

[0066] The following steps can be repeated multiple times to prepare a sufficient amount of product for the following processes.

[0067] 2. Preparation of foliar fertilizer: 1.2 parts by weight of polyethylene glycol PEG600, 1.2 parts by weight of quaternized modified cellulose nanocrystals, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were sequentially added to water and stirred until well mixed to obtain 100 parts by weight of the foliar fertilizer of Example 4.

[0068] The main difference between Example 4 and Example 1 is that the polyethylene glycol in Example 4 was not modified.

[0069] Example 5: Example 5 includes the following steps: 1. Preparation of cellulose nanocrystals: 75g of filter paper fragments were added to the reaction vessel, followed by 250mL of 64wt% sulfuric acid. The mixture was mechanically stirred at 45°C for 1.5h. After the reaction was completed, 500mL of cold water (approximately 4°C) was slowly added to terminate the reaction. The resulting suspension was centrifuged (4000rpm for 5min), washed three times with circulating water, and purified by dialysis (using a 3.5kDa dialysis bag for 24h) to obtain the cellulose nanocrystals of Example 5.

[0070] 2. Preparation of foliar fertilizer: 1.2 parts by weight of polyethylene glycol PEG600, 1.2 parts by weight of cellulose nanocrystals, 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, and 0.5 parts by weight of malic acid were added to water in sequence and stirred until well mixed to obtain 100 parts by weight of the foliar fertilizer of Example 5.

[0071] The main difference between Example 5 and Example 1 is that the polyethylene glycol and cellulose nanocrystals in Example 5 were not modified.

[0072] Example 6: 1.2 parts by weight of vitamin B (1 part by weight of vitamin B2, 0.1 parts by weight of vitamin B3, 0.05 parts by weight of vitamin B4 and 0.05 parts by weight of vitamin B5), 0.05 parts by weight of 6-benzylaminopurine, 0.03 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.45 parts by weight of rhamnolipid, 0.75 parts by weight of soluble sugar (0.15 parts by weight of glucose + 0.6 parts by weight of mannitol), 0.2 parts by weight of amino acids (0.05 parts by weight of glycine + 0.15 parts by weight of glutamic acid), and 0.5 parts by weight of malic acid were sequentially added to 97.77 parts by weight of water. After stirring and mixing, the foliar fertilizer of Example 6 was obtained.

[0073] Foliar fertilizer performance test: Ten groups of smoke trees with a diameter at breast height of 3-5 cm and similar growth were selected from the foothills of a city (altitude about 169m), with 6 trees in each group; the light and canopy cover of each smoke tree were consistent; 9 groups of smoke trees were treated with foliar fertilizers of Examples 1-6 and Comparative Examples 1-3, and one group was a control group with water.

[0074] The experiment was conducted from June to November 2024. Foliar fertilizer application was completed from June 9th to September 29th. From October 10th to November 30th, the leaf color change of *Cotinus coggygria* was observed daily and the changes were recorded. At four locations on each experimental plant, one 1-meter-long branch was selected. The red leaf stage was defined as when 5% of the leaves on the sample branch began to turn red; the peak red leaf stage was when 50% began to turn red and a certain visual effect was achieved; and the late red leaf stage was when 80% of the leaves had turned red. When three or more plants in each group met the conditions for the red leaf stage, that group was considered to have entered that stage. The results are shown in Table 1. Table 1 As can be seen, the foliar fertilizer of Example 1 has a significant effect on prolonging the ornamental period of smoke tree leaves. This is because the aminated polyethylene glycol prepared in Example 1 has hydroxyl and amino bifunctional groups. It can not only bind to the waxy layer of smoke tree leaves, but also bind to vitamin B and benzylaminopurine, thereby allowing the plant to slowly absorb vitamin B and benzylaminopurine, achieving a slow-release effect. Furthermore, the aminated polyethylene glycol forms a breathable membrane after drying, which does not hinder leaf respiration. Example 1 also prepared quaternized modified cellulose nanocrystals, which can interpenetrate with aminated polyethylene glycol to form a three-dimensional framework, achieving further slow release. Moreover, quaternization modification provides a certain positive charge, which can bind to the groups (hydroxyl and carboxyl groups) on the cuticle surface of smoke tree leaves, thereby achieving a better adhesion effect, allowing vitamin B and benzylaminopurine to be better absorbed by the leaves. In addition, it can be seen that the product of Example 1 can also significantly delay the leaf drop process of smoke tree leaves.

[0075] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein.

Claims

1. A foliar fertilizer for prolonging the ornamental period of colorful foliage plants, characterized in that, The foliar fertilizer contains the following components: B vitamins, benzylaminopurine compounds, ethylenediaminetetraacetic acid chelated titanium, rhamnolipids, soluble sugars, amino acids, and malic acid; The foliar fertilizer also contains the following components: modified polyethylene glycol and modified cellulose nanocrystals; The modified polyethylene glycol is an aminated polyethylene glycol; the modified cellulose nanocrystals are quaternized cellulose nanocrystals. The aminated modified polyethylene glycol is prepared by the following steps: Step 1-a: Dissolve polyethylene glycol in dichloromethane, then add p-toluenesulfonyl chloride and potassium hydroxide; stir for 24-48 hours; then wash and separate the contents. Step 2-a: Dissolve the product obtained in step 1-a in dichloromethane, and after drying, ether precipitation, and vacuum drying, obtain the intermediate product; Step 3-a: Dissolve the intermediate product obtained in step 2-a in ammonia water, then add ammonium chloride, and react at room temperature for 48-72 hours; Step 4-a: Add sodium chloride to the product obtained in step 3-a, then extract with dichloromethane, and after drying, ether precipitation and vacuum drying, obtain the aminated modified polyethylene glycol. The quaternized ammonium modified cellulose nanocrystals were prepared by the following steps: Step 1-b: Prepare cellulose nanocrystals and obtain an aqueous suspension of cellulose nanocrystals; Step 2-b: Add sodium hydroxide to the aqueous suspension of cellulose nanocrystals obtained in Step 1-b and stir at room temperature for 20-60 min; then add 2,3-epoxypropyltrimethylammonium chloride and react at 55℃-65℃ for 3-6 h under nitrogen protection. Step 3-b: After the reaction is complete, cool to room temperature, and obtain the quaternized ammonium modified cellulose nanocrystals after acetone precipitation, washing, and drying.

2. The foliar fertilizer for extending the ornamental period of colorful foliage plants according to claim 1, characterized in that, The soluble sugar includes at least one monosaccharide, disaccharide, or oligosaccharide; and at least one sugar alcohol.

3. The foliar fertilizer for extending the ornamental period of colorful foliage plants according to claim 1, characterized in that, The cellulose nanocrystals were prepared by the following steps: Step 1-c: Provide filter paper fragments; add the filter paper fragments to the reaction vessel; add sulfuric acid solution, and mechanically stir at 40℃-50℃ for 1-2 hours; Step 2-c: After the reaction is complete, add cold water to terminate the reaction; the resulting suspension is purified by centrifugation, washing with water, and dialysis to obtain the cellulose nanocrystals.

4. The foliar fertilizer for extending the ornamental period of colorful foliage plants according to claim 1, characterized in that, The vitamin B compounds are selected from one or more of vitamin B1, vitamin B2, vitamin B3, vitamin B4, vitamin B5, and vitamin B16, or a mixture thereof; the benzylaminopurine compounds are selected from 6-benzylaminopurine.

5. The foliar fertilizer for extending the ornamental period of colorful foliage plants according to claim 1, characterized in that, 100 parts by weight of the foliar fertilizer contains the following components in parts by weight: 0.5-1.5 parts by weight of B vitamins, 0.01-0.05 parts by weight of benzylaminopurine compounds, 0.02-0.05 parts by weight of ethylenediaminetetraacetic acid chelated titanium, 0.3-0.5 parts by weight of rhamnolipids, 0.5-1.0 parts by weight of soluble sugars, 0.2-0.3 parts by weight of amino acids, 0.4-0.8 parts by weight of malic acid, 0.5-1.5 parts by weight of modified polyethylene glycol, and 0.5-1.5 parts by weight of modified cellulose nanocrystals.

6. The foliar fertilizer for extending the ornamental period of colorful foliage plants according to any one of claims 1-5, characterized in that, The colorful foliage plants are selected from smoke tree, red maple, sugar maple, five-lobed maple, Japanese maple, treasury maple, purple barberry or tulip tree.

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