Flower cut flower composite preservative solution and application thereof

Abstract

The application discloses a flower cut flower composite preservative solution and application thereof, and belongs to the technical field of flower preservation. The flower cut flower composite preservative solution is prepared by compounding nano-silver, aluminum sulfate and boric acid, and the specific formula is as follows: 20 g / L Suc+3.7 mg / L NS+166.3 mg / L Al2(SO4)3+117.7 mg / L H3BO3. Traditional cut flower preservative solutions are divided into three types, namely pretreatment solution, flower accelerating solution and bottle insertion solution, and the single pertinence and complicated use method are improved, the preservative solution is convenient to use, the bottle insertion life of cut rose varieties is improved, and the flower opening diameter of cut rose flowers and the bottle insertion life are increased.

Description

Technical Field

[0001] This invention relates to the field of flower preservation technology, and more specifically to a composite preservative solution for cut flowers and its application. Background Technology

[0002] Postharvest senescence of cut flowers is a complex process involving the synergistic effects of multiple factors, including water imbalance, microbial proliferation, oxidative damage, and nutrient depletion. To extend vase life, traditional preservative solutions primarily rely on four categories of components: nutrient supplements (such as sucrose to maintain energy metabolism), antibacterial agents (such as 8-hydroxyquinoline to inhibit vascular blockage), plant growth regulators (such as gibberellin to delay senescence), and physical barrier agents (such as chitosan to reduce transpiration). While these technologies can extend vase life to some extent, they have significant limitations:

[0003] Functional limitations: Most formulations target only a single aging mechanism, making it difficult to achieve multiple anti-aging effects. For example, in the study "Screening and Preservation Effect of Silver-Free Preservative for Lily Cut Flowers (Zhao Min)," the lily preservative, through orthogonal optimization, obtained a sucrose-8-HQ-salicylic acid composite formulation, which extended vase life by 68.87%, but its effect on moisture balance regulation was insufficient. Similarly, in the study "Mechanism Study of Antitranspirant in Rose Cut Flower Preservation (Zheng Genbao)," the antitranspirant Vaporgard reduces water loss by closing stomata, but lacks antibacterial components.

[0004] Woody cut flowers have poor adaptability: Woody stem cut flowers such as roses are prone to vascular blockage due to lignification, and existing formulas are difficult to penetrate deep into the stem. For example, "Comparison of the preservation effects of different formula preservatives on hydrangea cut flowers, Li Huie" points out that although the formula containing silver nitrate achieves a vase life of 22.2 days, it is insufficient in regulating the microenvironment of woody stems.

[0005] Environmental toxicity risks: Mainstream commercial preservatives rely on high concentrations of silver salts (such as 30 mg / L AgNO3) or chemical bactericides (such as 250 mg / L 8-HQ), and their heavy metal residues and bioaccumulation raise ecological concerns.

[0006] Therefore, how to develop new composite preservative solutions for cut flowers with multiple anti-aging effects, good compatibility with woody cut flowers, and environmental friendliness is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides a composite preservative liquid for cut flowers and its application. The preservative liquid of the present invention has multiple anti-aging effects, good compatibility with woody cut flowers such as roses, and is environmentally friendly and safe.

[0008] To solve the above-mentioned technical problems, this application adopts the following technical solution: A composite preservative solution for cut flowers comprises the following components at final concentrations: 20 g / L sucrose, 3-4 mg / L nano silver, 150-200 mg / L aluminum sulfate, and 100-150 mg / L boric acid.

[0009] Sucrose's core functions are as an energy source and osmotic regulator. It provides energy by offering a substrate for the cut flowers' respiration, compensating for photosynthetic deficiencies, and delaying senescence. It also helps retain water by regulating osmotic pressure, aiding in water absorption and retention, and preventing wilting. Furthermore, it inhibits ethylene production in ethylene-sensitive flowers, extending their vase life. It works synergistically with nano-silver, aluminum sulfate, and boric acid to maintain the water balance and energy metabolism of cut flowers.

[0010] Nano silver (NS) possesses antibacterial properties, which can induce a plant defense response. This is achieved by inhibiting bacterial biofilm formation (such as in *Ureaplasma* and *Sphingomonas*), reducing the expression of genes related to cell wall degrading enzymes (such as pectinase and cellulase), maintaining the integrity of the vascular bundle structure, and indirectly reducing bacterial-induced ethylene synthesis and related gene activation. NS can also extend the vase life of roses by regulating stomatal closure and inhibiting ethylene synthesis.

[0011] Aluminum sulfate is readily soluble in water, and its aqueous solution is acidic (pH approximately 2.5–3.5). The aluminum ions (Al³⁺) and sulfate ions (SO₄²⁻) in its structure dissociate in aqueous solution and can exert physiological functions separately. Furthermore, aluminum sulfate can affect plant mineral absorption or pH regulation, thereby influencing hormone signaling and metabolic pathways.

[0012] The main functions of boric acid are to maintain water balance, promote nutrient absorption, and slow down the aging process.

[0013] As a preferred technical solution, the flower cut flower composite preservative solution comprises the following components at the following final concentrations: 20 g / L sucrose, 3.7 mg / L nano silver, 166.3 mg / L aluminum sulfate, and 117.7 mg / L boric acid.

[0014] As a preferred technical solution, the preservative liquid also includes other active ingredients and / or excipients.

[0015] As a preferred technical solution, the flower is a rose.

[0016] Another object of this application is to provide: the application of the aforementioned flower cut flower compound preservative liquid, wherein the application is in any of the following directions: (1) Application in the preservation of cut flowers; (2) Application in improving the vase life of cut flowers; (3) Application in improving the degree of opening and size of cut flower petals; (4) Application in delaying water loss in cut flowers; (5) Application in maintaining and / or increasing the fresh weight of cut flowers; (6) Application in reducing oxidative damage to cut flowers; (7) Application in delaying the senescence of cut flowers; (8) Application in improving the activity of SOD, POD and CAT enzymes in cut flowers; (9) Application in delaying the degradation of soluble proteins in cut flowers.

[0017] Another object of this application is to provide a method for using the aforementioned flower cut flower compound preservative solution, wherein the preservative solution is sprayed onto the surface of the cut flowers or the stem segments of the cut flowers are immersed in the preservative solution.

[0018] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects: This patent identifies an optimized compound preservative formulation, comprising nano-silver, aluminum sulfate, and boric acid, specifically: 20 g / L Suc + 3.7 mg / L NS + 166.3 mg / L Al2(SO4)3 + 117.7 mg / L H3BO3. Traditional cut flower preservatives are categorized into three types: pretreatment solution, flower-inducing solution, and vase solution. These are limited in their specific application and cumbersome in usage. This compound preservative is not only convenient to use but also improves the vase life of cut rose varieties, increases the opening diameter of rose flowers, and achieves a vase life of up to 11.2 days. Compared to existing cut flower preservatives, the use of nano-silver instead of 8-HQ and Al2(SO4)3 instead of CaCl2 or Ca(NO3)2 significantly extends vase life in single-factor experiments. Furthermore, the selected compound preservative formulation extends the vase life by 2.6 days compared to the commonly used commercially available KeliXian preservative. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1The diagram shows the surface response plots (left) and response surface analysis contour plots (right) for the interaction between NS and Al2(SO4)3; a is the surface response plot for the interaction between NS and H3BO3; b is the surface response plot for the interaction between NS and H3BO3; c is the surface response plot for the interaction between Al2(SO4)3 and H3BO3; d is the response surface analysis contour plot for NS and Al2(SO4)3; e is the response surface analysis contour plot for NS and H3BO3; and f is the response surface analysis contour plot for Al2(SO4)3 and H3BO3.

[0021] Figure 2 For: the concentration of each factor and the predicted vase life.

[0022] Figure 3 The effect of different preservative solutions on the change rate of cut rose flower diameter.

[0023] Figure 4 The effect of different preservative solutions on the moisture balance of cut roses.

[0024] Figure 5 The effect of different preservative solutions on the change rate of fresh weight of cut roses.

[0025] Figure 6 The effect of different preservative solutions on the MDA content of cut roses.

[0026] Figure 7 The effect of different preservative solutions on the Pro content of cut roses.

[0027] Figure 8 The effect of different preservative solutions on the SOD enzyme activity of cut roses.

[0028] Figure 9 The effect of different preservative solutions on the POD enzyme activity of cut roses.

[0029] Figure 10 To: The effect of different preservative solutions on the CAT enzyme activity of cut roses.

[0030] Figure 11 The effect of different preservative solutions on the soluble protein content of cut roses. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] The materials used in the embodiments of this application are as follows: The rose variety "Sweet Avalanche" was used as the experimental material. The experimental material was planted in Zhenhua Horticulture and Flower Industry Park in Taiyuan City, Shanxi Province. Flower branches that were free from pests and diseases, upright and strong, and with flowers of similar size and degree of opening were selected. The degree of opening was determined with reference to the technical regulations for cut rose production and combined with actual conditions. The rose cut flowers were harvested when the sepals were open, the outer petals were open, and the inner flower center was slightly loose. The harvesting time was from 8:00 am to 10:00 am. The average length of the flower branches harvested was about 60 cm, and the flower branches were thick.

[0033] Example 1 Screening of Preservatives To screen for highly efficient preservatives, we focused on five common components of preservative solutions: bactericides, inorganic salts, organic acids, plant growth regulators, and sugars. Multiple reagents were selected for screening, including nano-silver (NS), octa-hydroxyquinoline (8-HQ), chlorine dioxide (ClO2), calcium chloride (CaCl2), calcium sulfate (Ca(NO3)2), aluminum sulfate (Al2(SO4)3), hexa-benzylaminopurine (6-BA), gibberellin (GA3), auxin / indolebutyric acid (IBA), brassinolide (BR), citric acid (CA), boric acid (H3BO3), and sucrose (Suc). All treatments were prepared using distilled water. The experiment was conducted at the Flower Center of Taiyuan Horticulture Institute, College of Horticulture, Shanxi Agricultural University. Rosa “Sweet Avalanche” cut flowers were soaked in distilled water for two hours to fully absorb water. After soaking, the stems were cut underwater at a 45° angle, leaving 40 cm of stem. Each stem retained two leaves, and excess leaves and thorns were removed to minimize tissue damage. During vase life, the room temperature was maintained at 23±2℃, relative humidity at 50-60%, and natural diffused light indoors. Each treatment used 500 mL of vase solution, with five stems per vase, and each treatment was replicated three times. The control was distilled water (CK). Specific preservatives and experimental design are shown in Table 1. Flowering was observed daily, and vase life was recorded. The results are shown in Tables 2, 3, and 4.

[0034] Table 1. Single-factor screening experimental design for cut roses

[0035] Table 2. Effects of different fungicides on the vase life of cut roses.

[0036] Note: Data in the table are mean ± standard deviation. Different lowercase letters indicate significant differences (P < 0.05) between different concentrations of the same substance and the control. Materials were collected in groups, with high consistency required within each group. However, there were differences in materials between groups, resulting in different control (CK) values ​​for each group. Furthermore, the external environment during each experiment also affected the results. Therefore, comparisons can only be made within the same group. The control group (CK) was included to eliminate the influence of experimental materials and the external environment on the results. Table 3-6 follows the same principle.

[0037] Table 3. Effects of different organic acids on the vase life of cut roses

[0038] Note: The data in the table are mean ± standard deviation. Different lowercase letters indicate significant differences between different concentrations of the same substance and the control (P < 0.05).

[0039] Table 4. Effects of different inorganic salts on the vase life of cut roses

[0040] Table 5. Effects of different plant growth regulators on the vase life of cut roses.

[0041] Note: The data in the table are mean ± standard deviation. Different lowercase letters indicate significant differences between different concentrations of the same substance and the control (P < 0.05).

[0042] Table 6. Effects of different sucrose concentrations on the vase life of cut roses.

[0043] Note: The data in the table are mean ± standard deviation. Different lowercase letters indicate significant differences between different concentrations of the same substance and the control (P < 0.05).

[0044] Results analysis: The experiment shows that adding different types and concentrations of preservative solutions has different effects on the vase life of cut roses: Among different fungicide treatments, compared with the control, the addition of fungicides NS and 8-HQ significantly prolonged the vase life of roses. 3 mg / L NS and 50 mg / L 8-HQ showed the best effects, extending the vase life by 3.2 days and 1.4 days respectively, with 3 mg / L NS showing the best effect. ClO2, however, reduced the vase life of roses. During vase life, the cut ends of the roses gradually turned white, with the effect increasing with higher concentrations. This may be because the selected ClO2 concentration was too high, burning the cut rose flowers and reducing their vase life.

[0045] In different organic acid treatments, compared with the control, 300 mg / L CA and 100 mg / L H3BO3 extended the vase life of roses by 1.4 days and 1.8 days, respectively. Both CA and H3BO3 extended the vase life of roses, but 100 mg / L H3BO3 was more effective.

[0046] Among different inorganic salt treatments, 150 mg / L Al2(SO4)3 significantly increased the vase life of roses, extending it by 3 days compared to the control. CaCl2 and Ca(NO3)2 did not significantly extend the vase life.

[0047] In treatments with different plant growth regulators, 6-BA, GA3, and IBA did not significantly extend the vase life of roses.

[0048] In different sucrose concentration treatments, sucrose treatment did not increase the vase life of roses. The addition of sugar as a single factor increased microbial reproduction, blocked the vascular bundles of cut roses, and reduced vase life.

[0049] Example 2 Determining the optimal formula for vase preservation solution Based on the above single-factor experiments on cut roses, and according to the experimental results, we selected from the single factors that have a greater impact on the vase life of cut roses, and finally determined fungicide A (NS), inorganic salt B (Al2(SO4)3), and organic acid C (H3BO3) to conduct a three-factor, three-level response surface methodology experiment. According to the Box-Behnken central composite design, with the vase life (Y) of cut roses as the response value, we designed 17 vase experiments to observe the number of days the flowers were in the vase and determine the optimal vase preservation solution formula. The experimental factors and coding levels are shown in Table 7, and the experimental design and results are shown in Table 8.

[0050] Table 7. Factor Levels in the Box-Behnken Experiment

[0051] Table 8 Box-Behnken Experimental Design and Results

[0052] The experimental data in Table 8 were analyzed using Design Expert 13.0 software. A regression fitting was performed on the three independent variables—bactericide (A), inorganic salt (B), and organic acid (C)—and the response value, bottle life (Y), to predict the quadratic multivariate equation model as: Y = 10.58 + 0.3375A + 0.1625B + 0.125C + 0.3AB + 0.225AC + 0.075BC - 0.79A² - 0.44B² - 0.315C² In the formula, Y is the predicted value of the preservative solution formula for the vase life (d) of cut roses. The regression model and variance analysis results are shown in Table 9.

[0053] Table 9. Regression Model and Analysis of Variance Results

[0054] Note: This indicates a significant difference (P<0.05); This indicates a highly significant difference (P<0.01). Table 10 Model Feasibility Analysis

[0055] Table 9 shows that the F-value of the model is 46.91, P < 0.0001, indicating that the model is significant and statistically significant. The F-value of the lack-of-fit term in the regression model is 0.6373, P = 0.6295 > 0.05, indicating that the lack-of-fit term is not significant. The F-value can determine the influence of a single factor on the response value; the larger the F-value, the greater the influence. Therefore, the influence of a single factor on the experimental results, from largest to smallest, is A(NS) > B(Al2(SO4)3) > C(H3BO3). The interaction terms AB and AC have significant interactions, with AB > AC > BC. Among them, the interaction between NS and H3BO3 is the strongest. The quadratic term A... 2 B 2 C 2 All of these factors significantly affected the results.

[0056] As shown in Table 10, the coefficient of determination R 2 =0.9837, indicating that the equation has a high degree of fit to the experimental data, and the corrected coefficient of determination R0 is... 2 Adj = 0.9627, indicating that 96.27% of the response values ​​in the model can be explained by the model, which can be used to optimize the formulation of rose cut flower preservative solution.

[0057] In summary, using Box-Behnken 13.0 software to plot response surface curves and contour plots can intuitively reflect the influence of the interaction of various factors on the response value (Y). The greater the change in the response surface curve, the greater the impact of the treatment on vase life, and vice versa. As shown in Figure 1 (left), the effects of NS on Al2(SO4)3, NS on H3BO3, and Al2(SO4)3 on the vase life of cut roses are all interactive. The three response surface curves are all convex, with a high center and low edges, indicating that the concentrations of NS, Al2(SO4)3, and H3BO3 have a maximum effect on vase life, which can be solved according to the conditions.

[0058] The shape of contour lines on a contour map can reflect the strength of interactions. The more elliptical the contour lines, the stronger the interaction; the more circular the contour lines, the weaker the interaction. Figure 1 (Right) It can be seen that the interaction between AB and AC has a significant impact on the vase life.

[0059] according to Figure 1 and Figure 2 The model prediction results show that when the concentrations of each factor in the composite vase solution are NS=3.6507mg / L, Al2(SO4)3=166.32mg / L, and H3BO3=117.67mg / L, the optimal vase life of cut roses can theoretically be reached, which is 10.684 days.

[0060] Example 3 The preparation of compound preservative solution and its effect on the vase life of cut roses After obtaining the preservative solution formula, referring to other literature and combining the results of the single-factor sucrose screening in this experiment, it was found that adding sugars in the single-factor experiment would cause microbial growth and block the vascular bundles, thus failing to significantly increase the vase life of cut flowers. Therefore, different sucrose concentrations were added to the formula for screening, and the appropriate sucrose concentration was selected. The experimental results are shown in Table 11. Table 11 Effects of different sucrose concentrations in preservative solutions on the vase life of cut roses

[0061] Results Analysis: According to Table 11, adding 20 g / L sucrose to the preservative solution resulted in the best vase life for cut roses. The single-factor experiment with sucrose did not yield ideal results because adding sugar alone increases microbial growth and clogs the vascular bundles of the cut roses, thus reducing vase life. However, since sugar provides energy for plant survival, we added sucrose to the preservative solution selected to avoid the influence of microbial growth. The results also showed that adding sucrose increased vase life. Therefore, the final compound preservative solution formula was 20 g / L Suc + 3.7 mg / L NS + 166.3 mg / L Al2(SO4)3 + 117.7 mg / L H3BO3, which achieved a vase life of 11.2 days.

[0062] Example 4 Effects of compound preservative treatment on vase life and physiological and biochemical characteristics of cut roses Based on the results of Example 3 and combined with actual operation, the concentrations of various factors were adjusted to 3.7 mg / L for nano-silver, 166.3 mg / L for aluminum sulfate, and 117.7 mg / L for boric acid. A compound preservative solution was prepared to verify the preservation effect. Under the same conditions, the rose variety "Pink Snow Mountain" was used to verify the preservation effect. Distilled water was used as the blank control group, the compound preservative solution as the treatment group, and Kelixian as the control group. The experiment was set up with three replicates, with five cut flowers in each replicate. The vase life and physiological and biochemical characteristics of different groups of rose cut flowers were measured. (For the physiological experiment, 120 cut flowers were prepared, and 6 cut flowers were randomly selected. The 2nd to 6th layers of petals of the cut flowers were removed, the white part at the bottom of the petals was cut off, and the remaining part was chopped and immediately wrapped in tin foil and flash-frozen in liquid nitrogen. The flowers were then stored in an ultra-low temperature freezer at -80℃ for later use. Samples were taken every two days until the end of the vase life. After all samples were collected, the physiological and biochemical characteristics were measured uniformly.) The details are as follows: (1) Effect of compound preservative treatment on the vase life of cut roses Vase life (the standard for determining vase life is: the number of days from the start of the cut roses being placed in the vase is recorded as 0 days, and the number of days from when the cut roses show signs of water loss, wilting, and bending, and begin to lose their ornamental value is the vase life), the experimental results are shown in Table 12.

[0063] Table 12 Effects of different groups on the vase life of cut roses

[0064] The results showed that the compound preservative treatment extended the vase life of cut roses by 4.8 days and 2.6 days compared to the control and the preservative solution, respectively.

[0065] (2) Effect of compound preservative solution on the change rate of cut rose flower diameter Flower diameter: The diameter of cut rose flowers was measured using the cross-multiplication method. During the vase life of the cut flowers, the diameter of each cut flower was measured daily at 2 PM using vernier calipers. Each cut flower was measured twice using the cross-multiplication method, and the average of the two measurements was taken as the flower diameter for that day. The rate of change in flower diameter was then calculated.

[0066] Flower diameter change rate (%) = (Flower diameter on day n - Flower diameter at the beginning of the vase) / Flower diameter at the beginning of the vase × 100% Results analysis: The rate of change in flower diameter indicates the degree of flower opening and size, from Figure 3It can be seen that the flower diameter change rate of the three treatments gradually increased at the beginning. As the cut flowers gradually opened over time, the flower diameter change rate of the roses treated with the compound preservative increased the most, reaching a peak of 41.05% on the 5th day, and then gradually decreased. The rate of change of flower diameter of the cut roses treated with the compound preservative also reached a maximum of 38.34% on the 5th day, and that of the cut roses treated with water reached 33.68% on the 4th day. The flower diameter change rate of the cut roses treated with the compound preservative increased significantly, especially that of the cut roses treated with the compound preservative, indicating that the cut roses treated with the compound preservative can increase the degree of opening.

[0067] (3) Effects of preservative solution on the moisture balance and fresh weight change rate of cut roses Moisture balance: The moisture balance was determined by weighing. Starting from the day the cut roses were placed in the vase, the tissue culture bottle and the solution were weighed daily using an electronic balance. The difference between two consecutive weighing results was the amount of water absorbed by the solution during that period. The total weight of the flower stems, solution, and bottle was weighed, and the difference between the two weighings was the amount of water lost.

[0068] Moisture balance value = water absorption - water loss.

[0069] Fresh weight of cut flowers: At 5 p.m. each day, the cut flowers were removed from the bottle and placed horizontally on a balance to weigh their fresh weight. Five flowers were measured for each treatment.

[0070] Fresh weight change rate: The initial weight of the cut roses in the vase was measured using an electronic balance as W0, and the daily weight of the cut roses after vase placement was measured as W. d .

[0071] Fresh weight change rate (%) = [(W d -W0)] / W0]×100% In the formula: W0 is the initial weight of the cut rose flowers, W d This refers to the daily weight of cut roses during their vase arrangement, d=0, 1, 2, 3, 4… until the end of the observation period.

[0072] Results Analysis: Figure 4 It was found that different treatments resulted in different changes in the water balance of cut roses. Among the treatments, the control water treatment showed the earliest decrease in water balance to a negative value, followed by the Keli Fresh treatment, and finally the compound preservative solution. Of the three treatments, the compound preservative solution produced the best water balance data, with the highest maximum water balance value among the three treatments. Furthermore, the time it took for its water balance value to decrease from positive to negative was the 4th day of vase life, 2 days later than the control. Therefore, treatment with the compound preservative solution significantly improved the moisture status of cut roses, to some extent delaying water loss and promoting water balance.

[0073] Depend on Figure 5It can be seen that the rate of change of fresh weight in water treatment started to decrease first, reaching its maximum value on day 2, and then began to decrease, reaching a critical value on day 4, and turning negative on day 5 and continuing to decrease. Next, the rate of change of fresh weight in water treatment reached its maximum value on day 3, which was 1 day longer than that of water, and then began to decrease, reaching a critical value on day 5, turning negative on day 6 and continuing to decrease. Finally, the rate of change of fresh weight in compound preservative solution treatment first increased continuously until day 4, at which point it reached its maximum value, which was 2 days longer than that of water, and then began to decrease until day 8 when it turned negative, and then continued to decrease. This indicates that compound preservative solution has a significant promoting effect on increasing and maintaining the fresh weight of cut roses.

[0074] (4) Effects of preservative solution on malondialdehyde and proline in cut roses Determination of malondialdehyde (MDA) content The thiobarbituric acid (TBA) method was used. 0.1 g of cut rose petals were weighed, added to 5 mL of 5% trichloroacetic acid (TCA), and ground. The homogenate was transferred to a 10 mL centrifuge tube and centrifuged at 3000 r / min for 10 min. 2 mL of the supernatant was taken, and 2 mL of 0.67% thiobarbituric acid (TBA) was added. The mixture was boiled in a 100℃ boiling water bath for 30 min, cooled, and centrifuged again. The absorbance of the supernatant at wavelengths of 450 nm, 532 nm, and 600 nm was measured (a mixture of 2 mL of distilled water and 2 mL of 0.67% TBA was used as a control for colorimetric determination).

[0075] The calculation formula is as follows:

[0076] Determination of proline (Pro) content Plot a standard curve and determine the regression equation for the change in absorbance (y) with proline concentration (x). Weigh 0.1g of cut rose petals, place them in a tube, add 5mL of 3% sulfosalicylic acid solution, extract in a boiling water bath for 10min, cool, and filter into a clean test tube. The filtrate is the proline extract. Pipette 2mL of the extract into another clean, glass-stopped test tube, add 2mL of glacial acetic acid and 2mL of acidic phorate reagent, heat in a boiling water bath for 30min, and the solution will turn red. After cooling, add 4mL of toluene, shake for 30s, let stand, and transfer the supernatant to a 10mL centrifuge tube. Centrifuge at 3000r / min for 5min. Gently pipette the red proline toluene solution from the supernatant into a cuvette, using toluene as a blank control, and measure the absorbance at 520nm wavelength on a spectrophotometer.

[0077] The proline content (μg / mL) in 2 mL of the test solution was calculated based on the regression equation, and then the percentage of proline content in the sample was calculated.

[0078] Calculation formula: Proline content per unit fresh weight sample = [(x 5 / 2) / sample weight 10 6 ] 100% The standard curve for proline determined using this method is: y = 0.0767x + 0.0134, R0 2 =0.9931.

[0079] Results analysis: MDA content can reflect the degree of oxidative damage to cut rose cells. Figure 6 As can be seen, the MDA content in all treatments showed the same trend: initially decreasing, then accumulating and increasing with increasing vase time. The initial high MDA concentration may be due to incomplete rehydration after shearing; the subsequent decrease indicates that after a period of sufficient water absorption following the addition of vase solution, the cut roses maintained a low MDA level. From 0 to 2 days of vase time, the MDA content of CK and Kelix decreased, then steadily increased. The MDA content of the preservative solution decreased from 0 to 4 days, then began to increase after 4 days. From 4 to 8 days, the MDA content was preservative solution < Kelix < CK, indicating that the preservative solution and Kelix are more effective than water in reducing oxidative damage to cut rose cells, with the preservative solution being more effective in slowing down MDA formation.

[0080] Depend on Figure 7 It can be seen that during the vase life of cut roses, the proline content in the CK treatment gradually increased with the increase of vase life, while the proline content in the cut roses treated with KeliXian and the compound preservative showed a decreasing trend from 0 to 2 days, indicating that the addition of KeliXian and the preservative liquid reduced the proline content. After 2 days, the proline content gradually increased, and it remained at a relatively low level compared with the CK throughout the vase life. Compared with KeliXian, the compound preservative liquid had a lower proline content at the same vase life, indicating that both KeliXian and the compound preservative treatment can effectively slow down the accumulation of proline in cut roses, thereby improving the water balance and delaying the aging of roses, but the compound preservative liquid was more effective.

[0081] (5) Effects of preservative solution on SOD, POD and CAT in cut roses The activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) was measured using the Superoxide Dismutase (SOD) Activity Assay Kit, Peroxidase (POD) Activity Assay Kit, and Catalase (CAT) Activity Assay Kit, respectively, with the assay methods following the instructions of the kits.

[0082] Results Analysis: The effects of different preservative solutions on the SOD enzyme activity of rose petals are as follows: Figure 8During the vase period, the SOD enzyme activity of all treatments showed a trend of first decreasing, then increasing, and then decreasing again. The enzyme activity of CK reached its maximum value of 1360.13 U / g on day 4, that of Kelix reached its maximum value of 2767.04 U / g on day 6, and that of the compound preservative reached its maximum value of 3464.83 U / g on day 8. After that, all treatments began to decrease. The results indicate that, compared with CK, both Kelix and the compound preservative treatment can increase the SOD activity in rose petals. Kelix and the compound preservative treatment may play a role in maintaining the stability of the internal environment of rose petals and reducing the generation of free radicals such as superoxide anions.

[0083] Depend on Figure 9 It can be seen that the activity trends of POD enzymes in each treatment are basically the same. The CK treatment reached its maximum value of 19.27 U / g on day 4, the Kelixian treatment reached its maximum value of 30.55 U / g on day 4, and the compound preservative treatment reached its maximum value of 34.88 U / g on day 6, and then began to decline rapidly. The results show that the compound preservative treatment prolonged the time for the increase of POD enzyme activity compared with the Kelixian treatment. Both the Kelixian and compound preservative treatments can improve POD enzyme activity compared with the CK treatment.

[0084] Depend on Figure 10 It can be seen that the CAT enzyme activity in each treatment, like that of SOD and POD enzymes, generally showed a trend of first decreasing, then increasing, and then decreasing again. The CK reached its maximum value of 101.36 U / g on day 4, while the Kelixian and compound preservative treatments reached their maximum values ​​of 128.84 U / g and 161.50 U / g on day 6, respectively, and then both decreased rapidly. Compared with the CK, the Kelixian and compound preservative treatments prolonged the time for enzyme activity to increase and also increased the CAT enzyme activity.

[0085] (6) Effect of preservative solution on soluble protein in cut roses The protein content was determined using the Coomassie Brilliant Blue G-250 method. First, a standard curve was plotted. Sample extraction was performed by weighing 0.1 g of cut rose petals, grinding them into a homogenate with 5 mL of distilled water or buffer, centrifuging at 10000 r / min for 10 min, taking 1.0 mL of the supernatant, adding 5 mL of Coomassie Brilliant Blue G-250 solution, mixing thoroughly, and letting stand for 2 min before measuring the absorbance at 595 nm. The protein content was then determined using the standard curve.

[0086] Protein content in the sample = (C×VT) / (VS×WF×1000) (mg / g); In the formula: C is the protein content (μg) obtained from the standard curve; VT—total volume of extract (mL); VS — the volume of sample added during the assay (mL); WF — Sample mass (g).

[0087] The standard curve for soluble proteins determined using this method is: y = 0.0067x + 0.8532, R0 2 =0.9991.

[0088] Results analysis: Soluble proteins can improve the water retention capacity of petal cells and play a certain protective role in the membrane system of plant cells. Therefore, the level of soluble protein can be used as an indicator of cut flower senescence. Figure 11 It can be seen that with the increase of vase life, the soluble protein content of each treatment showed a trend of first increasing and then decreasing. The soluble protein content of water-treated cut roses gradually increased to 2.08 mg / g on day 4, and then began to decrease. The content of Kelex in the Kelex treatment also gradually increased and then began to decrease on day 4, but the soluble protein content of the Kelex treatment on day 4 was higher than that of the water treatment group, at 2.21 mg / g. Kelex treatment promoted the increase of soluble protein in cut roses and delayed the degradation of soluble protein in the following days. The soluble protein content of the compound preservative treatment reached a maximum of 2.59 mg / g on day 6, and then began to decrease. The compound preservative treatment significantly increased the soluble protein content and prolonged the time of peak appearance, thus delaying the degradation of soluble protein.

[0089] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0090] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A composite preservative solution for cut flowers, characterized in that, The components include the following final concentrations: 20 g / L sucrose, 3-4 mg / L nano silver, 150-200 mg / L aluminum sulfate, and 100-150 mg / L boric acid.

2. The composite preservative solution for cut flowers according to claim 1, characterized in that, The components include the following final concentrations: 20 g / L sucrose, 3.7 mg / L nano silver, 166.3 mg / L aluminum sulfate, and 117.7 mg / L boric acid.

3. The composite preservative solution for cut flowers according to claim 1, characterized in that, It also includes other active ingredients and / or excipients.

4. The composite preservative solution for cut flowers according to claim 1, characterized in that, The flower in question is a rose.

5. The application of the composite preservative solution for cut flowers according to any one of claims 1-4, wherein the application is in any of the following directions: (1) Application in the preservation of cut flowers; (2) Application in improving the vase life of cut flowers; (3) Application in improving the degree of opening and size of cut flower petals; (4) Application in delaying water loss in cut flowers; (5) Application in maintaining and / or increasing the fresh weight of cut flowers; (6) Application in reducing oxidative damage to cut flowers; (7) Application in delaying the senescence of cut flowers; (8) Application in improving the activity of SOD, POD and CAT enzymes in cut flowers; (9) Application in delaying the degradation of soluble proteins in cut flowers.

6. The method of using the composite preservative solution for cut flowers according to any one of claims 1-4, characterized in that, Spray the preservative solution onto the surface of the cut flowers or soak the stem segments of the cut flowers in the preservative solution.

Images