Application of molybdenum disulfide nanoparticles in preparation of tomato leaf fertilizer

Abstract

The invention provides application of molybdenum disulfide nanoparticles in preparation of a tomato leaf fertilizer, and particularly relates to the technical field of tomato fertilizers. The molybdenum disulfide nano-particles act on tomato plants in a foliage spraying manner, so that the growth of the tomato plants is promoted and / or the fruit quality is improved. The molybdenum disulfide nanoparticles are used as the foliar fertilizer to significantly increase the plant height and stem diameter of tomatoes, increase the chlorophyll content and trace element content of plants, increase the vitamin C content, soluble sugar content and soluble solid content of tomato fruits, and significantly increase the accumulation of Mo and S of plants through the sulfur-molybdenum synergistic effect, so that the yield of the tomatoes is increased. A scientific basis is provided for reasonable application of the nano molybdenum fertilizer, and a way is opened up for high-yield and high-quality cultivation of tomatoes.

Description

Technical Field

[0001] The invention belongs to the technical field of tomato fertilizers, and particularly relates to the application of molybdenum disulfide nanoparticles in the preparation of tomato foliar fertilizers. Background Art

[0002] In recent years, nanomaterials have shown broad application prospects in the agricultural field due to their unique physical and chemical properties, such as surface and interface effects, quantum size effects, small size effects, and macroscopic effects. For example, zinc oxide nanoparticles and titanium dioxide nanoparticles have been shown to improve the photosynthetic efficiency and disease resistance of crops. The potential of nanomaterials in agriculture is not limited to nutrient delivery, but also includes the use as plant growth regulators, pesticide carriers, and soil conditioners. However, the large-scale application of nanomaterials in agriculture still faces challenges, such as safety assessment, cost-effectiveness analysis, and determination of optimal application concentrations. Therefore, exploring the specific effects and mechanisms of action of nanomaterials in crop production is of great theoretical and practical significance.

[0003] Tomato (Solanum lycopersicum) is one of the most important vegetable crops worldwide, rich in vitamin C, lycopene, and various minerals. Tomatoes are sensitive to molybdenum, and an adequate supply of molybdenum can significantly improve photosynthesis and fruit quality. However, the application of traditional molybdenum fertilizers (such as ammonium molybdate) suffers from low utilization rates and leaching. The use of molybdenum disulfide nanoparticles to promote tomato plant growth and enhance fruit quality has not been reported in the prior art. Summary of the Invention

[0004] The purpose of the present invention is to provide the use of molybdenum disulfide nanoparticles in the preparation of tomato foliar fertilizer. Molybdenum disulfide nanoparticles significantly promote the growth of tomato plants and improve the quality of fruits.

[0005] The present invention provides application of molybdenum disulfide nanoparticles in preparing tomato foliar fertilizer.

[0006] The present invention also provides the use of molybdenum disulfide nanoparticles in promoting the growth of tomato plants and / or improving the quality of fruits. The molybdenum disulfide nanoparticles act on the tomato plants by foliar spraying.

[0007] Preferably, the promoting of tomato plant growth includes increasing plant height and stem thickness; and the improving of fruit quality includes one or more of increasing fruit vitamin C content, increasing fruit soluble sugar content, and increasing fruit soluble solid content.

[0008] The present invention also provides the use of molybdenum disulfide nanoparticles in increasing chlorophyll content, wherein the molybdenum disulfide nanoparticles act on tomato plants by foliar spraying.

[0009] The present invention also provides the use of molybdenum disulfide nanoparticles in increasing the trace element content, Mo content and / or S content of tomato plants, wherein the molybdenum disulfide nanoparticles act on the tomato plants by foliar spraying.

[0010] Preferably, the trace elements include one or more of Fe, Mn, Cu and Zn.

[0011] The present invention also provides a method for improving the growth condition of tomato plants and the quality of fruits, wherein the molybdenum disulfide nanoparticles are sprayed on the leaves when the tomato seedlings grow to the five-leaf stage.

[0012] Preferably, the concentration of the molybdenum disulfide nanoparticles is in the range of 0.025 to 0.100 mg / mL.

[0013] Preferably, the spraying amount of the molybdenum disulfide nanoparticles per tomato plant is 0.4 mL each time; starting from the first spraying, spray once every 5 days, for a total of 5 sprays.

[0014] Preferably, when spraying on the leaves, pay attention to spraying evenly on both sides of the leaves until the leaves are filled with spray droplets.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention provides the use of molybdenum disulfide nanoparticles in the preparation of tomato foliar fertilizer. The molybdenum disulfide nanoparticles are applied to tomato plants by foliar spraying, significantly increasing the plant height and stem diameter of the tomato plants, increasing the content of trace elements in the tomato plants, increasing the vitamin C content of the fruit, increasing the soluble sugar content of the fruit, and increasing the soluble solids content of the fruit, thereby significantly promoting the growth of the tomato plants and improving the quality of the tomato fruit. The synergistic effect of sulfur and molybdenum also significantly increases the accumulation of Mo and S in the plants, providing a scientific basis for the rational application of nano-molybdenum fertilizers, and opening up a new path for the high-yield and high-quality cultivation of tomatoes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the effect of molybdenum disulfide nanoparticles on the height of tomato plants in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0018] Figure 2This is the effect of molybdenum disulfide nanoparticles on the stem diameter of tomato plants in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0019] Figure 3 This is the effect of molybdenum disulfide nanoparticles on the chlorophyll of tomato plants in Example 1, where CK is spraying with water, T1 is spraying with 0.025 mg / mL MoS2 NPs, T2 is spraying with 0.050 mg / mL MoS2 NPs, T3 is spraying with 0.075 mg / mL MoS2 NPs, and T4 is spraying with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0020] Figure 4 This is the effect of molybdenum disulfide nanoparticles on the Fe content in tomato plant leaves in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0021] Figure 5 This figure shows the effect of molybdenum disulfide nanoparticles on the Fe content in the roots of tomato plants in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0022] Figure 6 This figure shows the effect of molybdenum disulfide nanoparticles on the Mn content in tomato plant leaves in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0023] Figure 7This figure shows the effect of molybdenum disulfide nanoparticles on the Mn content in the roots of tomato plants in Example 1, where CK represents spraying with water, T1 represents spraying with 0.025 mg / mL MoS2 NPs, T2 represents spraying with 0.050 mg / mL MoS2 NPs, T3 represents spraying with 0.075 mg / mL MoS2 NPs, and T4 represents spraying with 0.100 mg / mL MoS2 NPs; the same lowercase letters indicate no significant difference at the p<0.05 level.

[0024] Figure 8 The effect of molybdenum disulfide nanoparticles on the Cu content in tomato plant leaves in Example 1, where CK represents spraying with water, T1 represents spraying with 0.025 mg / mL MoS2 NPs, T2 represents spraying with 0.050 mg / mL MoS2 NPs, T3 represents spraying with 0.075 mg / mL MoS2 NPs, and T4 represents spraying with 0.100 mg / mL MoS2 NPs; the same lowercase letters indicate no significant difference.

[0025] Figure 9 This figure shows the effect of molybdenum disulfide nanoparticles on the Cu content in the roots of tomato plants in Example 1, where CK represents spraying with clean water, T1 represents spraying with 0.025 mg / mL MoS2 NPs, T2 represents spraying with 0.050 mg / mL MoS2 NPs, T3 represents spraying with 0.075 mg / mL MoS2 NPs, and T4 represents spraying with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences.

[0026] Figure 10 Effect of molybdenum disulfide nanoparticles on the Zn content in tomato plant leaves in Example 1, where CK was sprayed with water, T1 was sprayed with 0.025 mg / mL MoS2 NPs, T2 was sprayed with 0.050 mg / mL MoS2 NPs, T3 was sprayed with 0.075 mg / mL MoS2 NPs, and T4 was sprayed with 0.100 mg / mL MoS2 NPs; the same lowercase letters indicate no significant difference.

[0027] Figure 11 This figure shows the effect of molybdenum disulfide nanoparticles on the Zn content in the roots of tomato plants in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0028] Figure 12This figure shows the effect of molybdenum disulfide nanoparticles on the Mo content in tomato plant leaves in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0029] Figure 13 This figure shows the effect of molybdenum disulfide nanoparticles on the Mo content in the roots of tomato plants in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0030] Figure 14 This is the effect of molybdenum disulfide nanoparticles on the S content in tomato plant leaves in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0031] Figure 15 This is the effect of molybdenum disulfide nanoparticles on the S content in the roots of tomato plants in Example 1, where CK is sprayed with water, T1 is sprayed with 0.025 mg / mL MoS2 NPs, T2 is sprayed with 0.050 mg / mL MoS2 NPs, T3 is sprayed with 0.075 mg / mL MoS2 NPs, and T4 is sprayed with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0032] Figure 16 This is the effect of molybdenum disulfide nanoparticles on the vitamin C content of tomato fruit in Example 1, where CK is spraying water, T1 is spraying 0.025 mg / mL MoS2 NPs, T2 is spraying 0.050 mg / mL MoS2 NPs, T3 is spraying 0.075 mg / mL MoS2 NPs, and T4 is spraying 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0033] Figure 17This figure shows the effect of molybdenum disulfide nanoparticles on the soluble sugar content of tomato fruit in Example 1, where CK is spraying water, T1 is spraying 0.025 mg / mL MoS2 NPs, T2 is spraying 0.050 mg / mL MoS2 NPs, T3 is spraying 0.075 mg / mL MoS2 NPs, and T4 is spraying 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level.

[0034] Figure 18 This figure shows the effect of molybdenum disulfide nanoparticles on the soluble solids content of tomato fruit in Example 1, where CK represents spraying with water, T1 represents spraying with 0.025 mg / mL MoS2 NPs, T2 represents spraying with 0.050 mg / mL MoS2 NPs, T3 represents spraying with 0.075 mg / mL MoS2 NPs, and T4 represents spraying with 0.100 mg / mL MoS2 NPs; different lowercase letters indicate significant differences at the p<0.05 level. DETAILED DESCRIPTION

[0035] The present invention provides the use of molybdenum disulfide nanoparticles in preparing tomato foliar fertilizer. In the present invention, the concentration range of the molybdenum disulfide nanoparticles is preferably 0.025 to 0.100 mg / mL.

[0036] The present invention also provides the use of molybdenum disulfide nanoparticles in promoting the growth of tomato plants and / or improving the quality of fruits. The molybdenum disulfide nanoparticles act on the tomato plants by foliar spraying.

[0037] In the present invention, the method of promoting tomato plant growth is preferably to increase plant height and stem diameter; and the method of improving fruit quality is preferably to increase one or more of the following: increasing fruit vitamin C content, increasing fruit soluble sugar content, and increasing fruit soluble solid content. Spraying MoS2 NPs at a concentration of 0.050 mg / mL increased tomato plant height by 22.34%, and spraying MoS2 NPs at a concentration of 0.050 mg / mL increased tomato stem diameter by 5.16%.

[0038] In the present invention, the vitamin C content of tomato fruit sprayed with MoS2 NPs at a concentration of 0.050 mg / mL increased by 33.76%; the soluble sugar content of tomato fruit sprayed with MoS2 NPs at a concentration of 0.050 mg / mL increased by 53.00%, and the soluble sugar content of tomato fruit reached 5.60%; the soluble solid content of tomato fruit sprayed with MoS2 NPs at a concentration of 0.025 mg / mL increased by 22.04%.

[0039] The present invention also provides the use of molybdenum disulfide nanoparticles to increase chlorophyll content. The molybdenum disulfide nanoparticles were applied to tomato plants via foliar spraying. In this study, spraying tomato plants with a concentration of 0.075 mg / mL of MoS2 NPs increased chlorophyll content in leaves by 62.46%.

[0040] The present invention also provides the use of molybdenum disulfide nanoparticles for increasing trace element content, Mo content, and / or S content in tomato plants. The molybdenum disulfide nanoparticles are applied to the tomato plants via foliar spraying. The trace elements are preferably one or more of Fe, Mn, Cu, and Zn.

[0041] In the present invention, the iron content of tomato leaves sprayed with MoS2 NPs at a concentration of 0.100 mg / mL increased by 80.39%, and the iron content of tomato roots sprayed with MoS2 NPs at a concentration of 0.075 mg / mL increased by 220.75%; the manganese content of tomato leaves sprayed with MoS2 NPs at a concentration of 0.025 mg / mL increased by 55.80%; the copper content of tomato roots sprayed with MoS2 NPs at a concentration of 0.075 mg / mL increased by 86.17%; the zinc content of tomato roots sprayed with MoS2 NPs at a concentration of 0.075 mg / mL increased by 194.30%; the molybdenum content of tomato leaves sprayed with MoS2 NPs at a concentration of 0.100 mg / mL increased by 181.48%, and the molybdenum content of tomato roots increased by 83.23%; the molybdenum content of tomato leaves sprayed with MoS2 NPs at a concentration of 0.100 mg / mL increased by 181.48%, and the molybdenum content of tomato roots increased by 83.23%; the molybdenum content of tomato roots sprayed with MoS2 NPs at a concentration of 0.100 mg / mL increased by 181.48%. The sulfur content in the leaves of tomatoes treated with NPs increased by 57.12%, and the sulfur content in the roots of tomatoes sprayed with MoS2 NPs at a concentration of 0.075 mg / mL increased by 74.05%.

[0042] The present invention also provides a method for improving tomato plant growth and fruit quality. Foliar spraying of the molybdenum disulfide nanoparticles is initiated when tomato seedlings reach the five-leaf stage. The concentration of the molybdenum disulfide nanoparticles is preferably in the range of 0.025 to 0.100 mg / mL. The spray rate of the molybdenum disulfide nanoparticles is 0.4 mL per tomato plant. Starting with the first spraying, spray once every five days for a total of five sprayings. When spraying foliarly, ensure that both sides of the leaves are sprayed evenly until the leaves are filled with spray droplets.

[0043] In the present invention, the molybdenum disulfide nanoparticles (MoS2 NPs) were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. The product name is: [M431857-1g] Molybdenum (IV) sulfide (1g), Cas number: 1317-33-5; ≥99% metals basis, nanopowder, 90nm; diameter (Aps).

[0044] In the present invention, the tomato variety is 'Red Pearl', which is a commercially available variety. The tomato variety 'Red Pearl' in the embodiment was purchased from Taobao-Wentian Seed Industry.

[0045] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the materials, reagents, and fertilizers used are all commercially available unless otherwise specified.

[0046] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0047] Example 1

[0048] 1 Materials and Methods

[0049] 1.1 Test materials

[0050] Test plants: Tomato ‘Red Pearl’;

[0051] Test fertilizer: Molybdenum disulfide nanoparticles (MoS2 NPs), purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., product name: [M431857-1g] Molybdenum (IV) sulfide (1g), Cas number: 1317-33-5; ≥99% metals basis, nanopowder, 90nm; diameter (Aps);

[0052] Main test reagents: 75% alcohol, ascorbic acid, 2,6-dichlorophenol indophenol, sodium bicarbonate, oxalic acid, 98% concentrated sulfuric acid, anthrone reagent, glucose, phenolphthalein indicator, sodium hydroxide, concentrated nitric acid, perchloric acid;

[0053] Main instruments and equipment: constant temperature water bath, autoclave, soft tape measure, electronic digital caliper, electronic balance, drying oven, spectrophotometer, acid burette, alkaline burette, mortar, digestion furnace, fume hood, inductively coupled plasma mass spectrometer;

[0054] 1.2 Experimental treatment

[0055] The experiment set up five treatments:

[0056] CK: spraying with clean water;

[0057] T1: spraying 0.025 mg / mL MoS2 NPs;

[0058] T2: spraying 0.050 mg / mL MoS2 NPs;

[0059] T3: spraying 0.075 mg / mL MoS2 NPs;

[0060] T4: spraying 0.100 mg / mL MoS2 NPs;

[0061] The molybdenum disulfide nanoparticles purchased above ([M431857-1g] molybdenum (IV) sulfide (1g), Cas number: 1317-33-5) were diluted with clean water to a fixed concentration (T1: 0.025 mg / mL MoS2 NPs; T2: 0.050 mg / mL MoS2 NPs; T3: 0.075 mg / mL MoS2 NPs; T4: 0.100 mg / mL MoS2 NPs).

[0062] The experiment was repeated 3 times.

[0063] The experiment was conducted in the light room and rooftop plastic greenhouse of the third teaching experimental building of Sichuan Agricultural University in 2023.

[0064] Tomato seedlings were raised on July 29, 2023. Full and uniform tomato seeds were selected, rinsed with deionized water, then soaked in 10% hydrogen peroxide for 15 minutes, rinsed 3-4 times with sterile water, and finally soaked in sterile water for 15 minutes. The seeds were placed in a moistened petri dish, covered with moistened gauze, and placed in a light incubator. Germination and rooting were accelerated at room temperature in the dark. When the roots grew to 1-2 cm, they were planted in a 32-hole hole tray. The hole tray soil was a mixture of Danish Pins Flower Nutrition Soil (Pins Top Horticulture (Shanghai) Co., Ltd.; Product No.: msh-1013) and vermiculite in a ratio of 1:1. The degree of moisture should be such that it can be clumped in the hand without dripping water. Tomatoes were grown in a greenhouse. Once white, the seeds were sown in a plug tray filled with a seedling medium (nutrient soil: vermiculite = 3:1) and placed in the light room of the Third Teaching Laboratory Building of Sichuan Agricultural University. The light cycle was 12 hours (25±2°C during the day and 20±2°C during the night). Water was added to the bottom of the seedling tray as needed during the cultivation process.

[0065] On September 5, 2023, when the seedlings had three leaves and one heart, select seedlings with similar growth patterns for transplanting and planting. Prepare a corresponding number of pots with a base diameter of 15 cm, a height of 15 cm, and a top diameter of 20 cm. Mix nutrient soil and vermiculite in a ratio of 3:1 and fill the pots. Transplant the seedlings into the pots and water them immediately. Cultivate them in a plastic greenhouse in the Third Teaching Laboratory Building of Sichuan Agricultural University, with each pot 0.3 m apart. Maintain consistent management conditions for all plants.

[0066] The test treatment was started when the tomato seedlings grew to the five-leaf stage. When spraying on the leaves, the spraying amount was 0.4 mL per plant each time, and sprayed once every five days, for a total of five times. Pay attention to spraying evenly on both sides of the leaves until the leaves are full of spray droplets. One month after the spraying is completed, a part of the leaves are randomly and evenly picked and dried for sampling. During the growth and development of the plants, the growth status of the aboveground parts of the plants is photographed regularly, and the changes in plant height, stem diameter and leaf chlorophyll content are recorded. The fruit quality is measured after the tomatoes are fruited. Finally, the aboveground and underground parts of the plants are weighed, and the fresh weight is recorded. After taking pictures of the underground parts, the samples are dried, weighed, and the dry weight is recorded.

[0067] 1.3 Measurement indicators and methods

[0068] Plant height: When the plant is mature, use a soft tape measure to measure the length from the base of the plant stem to the growth point of the top leaf of the main stem;

[0069] Stem diameter: When the plant is mature, use a vernier caliper to measure the diameter of the middle part of the plant;

[0070] Chlorophyll content: SPAD-502Plus portable chlorophyll meter was used to measure the fully expanded functional leaves at the same position of the plant. Four plants were measured for each treatment, with three leaves for each plant, and the average value was taken.

[0071] Fresh weight: Fresh weight was determined using an electronic balance;

[0072] Dry weight: Place the fresh weight of the tomato parts in a dryer at 80°C until constant weight is reached, then remove them and measure the dry weight using an electronic balance.

[0073] Soluble solids: Cherry tomato fruit juice was aspirated with a dropper and measured directly using a handheld refractometer;

[0074] Vitamin C content: Determined by 2,6-dichlorophenol indophenol titration method;

[0075] Soluble sugar: determined by sulfuric acid-anthrone colorimetric method;

[0076] Contents of metal ions Fe, Mn, Cu, Zn, Mo, and S: Plant samples were ground and thoroughly digested with perchloric acid and nitric acid (1:3). After becoming colorless and clear, they were determined using an ICP-MS mass spectrometer.

[0077] Each sample was repeated three times, and a blank test was also performed.

[0078] Data processing: The data were statistically analyzed by analysis of variance (ANOVA) using SPSS and Excel software. The least significant difference (LSD) test was used to determine the significant differences between means at a significance level of p < 0.05, and graphs were created using GraphPadPrism 8.0 software.

[0079] 2 Results Analysis

[0080] 2.1 Effects of MoS2 nanoparticles on plant height and stem diameter of tomato plants

[0081] like Figure 1 There was no significant difference between the T3 and T4 treatments and the CK, while the T1 and T2 treatments were significantly higher than the CK. There was no significant difference between the T1 and T2 treatments, but both were significantly higher than the T4 treatment. Therefore, the T1 and T2 treatments had the best effect on increasing tomato plant height, increasing by 14.67% and 22.34% respectively compared to the CK. The average plant height of the T2 treatment reached 16.43 cm.

[0082] Depend on Figure 2 It can be seen that, with the exception of T4, which showed no significant difference from CK, all other treatments showed a significant increase in stem diameter compared to CK. There were no significant differences between the T1, T2, and T3 treatments, which were 2.90%, 5.16%, and 3.25% higher than CK, respectively. Tomato plants in the T2 treatment had the largest stem diameter, reaching an average of 5.50 cm.

[0083] 2.2 Effects of MoS2 nanoparticles on chlorophyll in tomato plants

[0084] Depend on Figure 3 It can be seen that all treatments were significantly different from the control. The chlorophyll content of the leaves of the plants in the T3 treatment was the highest, at 50.54 SPAD, which was 62.46% higher than the control; followed by the T4, T2 and T1 treatment groups, which were 47.21, 45.49 and 31.11 SPAD respectively. The differences among the three were significant, which were 51.75%, 46.22% and 32.50% higher than the control respectively.

[0085] 2.3 Effects of MoS2 nanoparticles on the contents of trace elements Fe, Mn, Cu, and Zn in tomato plants

[0086] Depend on Figure 4 and Figure 5 It can be seen that compared with the control group, spraying MoS2 NPs can increase the iron content in tomato leaves and roots to varying degrees. Figure 4 As shown in the figure, the iron content of the leaves in the T4 treatment group was the highest, 80.39% higher than that in the control group, which was significantly different from the control group and other treatment groups; the iron content in the leaves of the T1, T2 and T3 treatment groups were 18.96%, 8.57% and 35.22% higher than that in the control group, respectively, and there was no significant difference among the three treatment groups; Figure 5As shown in the data, with the increase of the concentration of sprayed MoS2NPs, the iron content in the tomato roots first increased and then decreased. Among them, the root iron content of the T3 treatment group was the highest, 220.75% higher than that of the control group, which was significantly different from the control group; followed by the T4 treatment group, whose root iron content was 194.16% higher than that of the control group, and there was no significant difference with the T3 treatment group; this shows that spraying MoS2NPs can significantly increase the iron content in the leaves and roots of tomato plants, and its effect on the roots is more obvious than that on the leaves, and the difference in iron content is more significant when the concentration of the spraying material is high.

[0087] Depend on Figure 6 It can be seen that only the T1 treatment group and the control group had significant differences in manganese content in leaves, which was 55.80% higher than the control. As the concentration continued to increase, the manganese content in tomato plant leaves also tended to decrease; Figure 7 There was no significant difference in the manganese content in tomato roots among the treatments, which indicated that spraying different concentrations of MoS2 NPs did not seem to have a direct effect on the manganese content in tomato roots.

[0088] like Figure 8 There was no significant difference in the copper content of tomato plant leaves among the treatments, which indicated that spraying different concentrations of MoS2 NPs did not seem to have a direct effect on the copper content of tomato plant leaves; Figure 9 It can be seen that except for the significant difference in tomato root copper content between T3 and CK, the copper content of tomato roots in the other treatments had no significant difference compared with CK. The copper content of tomato roots in the T3 treatment was the highest, 86.17% higher than that in the control.

[0089] Depend on Figure 10 It can be seen that there is no significant difference in the zinc content of tomato plant leaves among the treatments, which indicates that spraying different concentrations of MoS2 NPs does not seem to have a direct effect on the zinc content of tomato plant leaves; Figure 11 It can be seen that except for the significant differences in zinc content in tomato roots between T2 and T3 and CK, the zinc content in tomato roots of the other treatments was not significantly different from that of CK. The zinc content in tomato roots under the T3 treatment was the highest, 194.30% higher than the control, followed by the T2 treatment, which was 183.08% higher than the control. This indicates that MoS2 NPs at concentrations between T2 and T3 treatments have the greatest effect on zinc content in tomato roots.

[0090] 2.4 Effects of MoS2 nanoparticles on Mo and S content in tomato plants

[0091] Depend on Figure 12 and Figure 13 It can be seen that compared with the control group, spraying MoS2 NPs can increase the molybdenum content in tomato leaves and roots to varying degrees. Figure 12As shown in the figure, with the increase of the concentration of MoS2 NPs sprayed, the molybdenum content in tomato leaves continued to increase. Among them, the molybdenum content in the leaves of the T4 treatment group was the highest, 181.48% higher than that of the control group, and significantly different from the control group and other treatment groups; the molybdenum content in the leaves of the T1, T2, and T3 treatment groups were 64.58%, 60.61% and 56.30% higher than that of the control group, respectively, and all three treatment groups were significantly different from the control group; Figure 13 As shown in the data, with the increase of the concentration of MoS2 NPs sprayed, the molybdenum content in the tomato roots continued to increase, among which the root molybdenum content of the T4 treatment group was the highest, 83.23% higher than that of the control group, which was significantly different from the control group; the molybdenum content in the roots of the T1, T2, and T3 treatment groups were 55.25%, 60.50% and 60.60% higher than that of the control group, respectively, and there was no significant difference between the three treatment groups; this shows that spraying MoS2 NPs can significantly increase the molybdenum content in the leaves and roots of tomato plants, and its effect on the leaves is more obvious than that on the roots.

[0092] Depend on Figure 14 and Figure 15 It can be seen that compared with the control group, spraying MoS2 NPs can affect the sulfur content in tomato leaves and roots to varying degrees. Figure 14 As shown in the figure, the sulfur content in the leaves of the T4 treatment group was the highest, 57.12% higher than that of the control group, and significantly different from the control group and other treatment groups. The sulfur content in the leaves of the other treatment groups was not significantly different from that of the control group. Figure 15 As shown in the data, with the increase of the concentration of sprayed MoS2 NPs, the sulfur content in the tomato roots first increased and then decreased. Among them, the sulfur content in the roots of the T3 treatment group was the highest, 74.05% higher than that of the control group, which was significantly different from the control group; the sulfur content in the roots of the T1, T2 and T4 treatment groups were 30.33%, 54.30% and 66.92% higher than that of the control group, respectively; indicating that spraying MoS2 NPs can significantly increase the sulfur content in the leaves and roots of tomato plants. When the concentration of MoS2 NPs is too low, it has an inhibitory effect on the accumulation of sulfur in tomato leaves, and its effect on the roots is more obvious than that on the leaves.

[0093] 2.5 Effect of MoS2 Nanoparticles on Vitamin C Content in Tomato Fruit

[0094] Depend on Figure 16It can be seen that compared with the control group, spraying MoS2 NPs can affect the vitamin C content of tomato fruit to varying degrees. The vitamin C content of the fruit in the T2 treatment group was the highest, 33.76% higher than that of the control group, which was significantly different from the control group. The vitamin C content of the fruit in the T1, T3, and T4 treatment groups was 18.40%, 9.05%, and 13.32% higher than that of the control group, respectively, with no significant differences among the three treatment groups. This shows that foliar spraying of MoS2 NPs can increase the vitamin C content of tomato fruit.

[0095] 2.6 Effect of MoS2 Nanoparticles on Soluble Sugar Content in Tomato Fruit

[0096] like Figure 17 Compared with the CK, the soluble sugar content of tomato fruits in all treatments except T4 was significantly increased. There was no significant difference between the T1, T2, and T3 treatments, but they were all significantly higher than the CK, increasing by 44.00%, 53.00%, and 24.59%, respectively. The soluble sugar content of tomato fruits in the T2 treatment reached 5.60%.

[0097] 2.7 Effect of MoS2 Nanoparticles on Soluble Solids Content in Tomato Fruit

[0098] Depend on Figure 18 It can be seen that only the soluble solids content of tomato fruit between the T1 treatment group and the control group was significantly different, which was 22.04% higher than the control; there were no significant differences between the other treatment groups and the control group, indicating that the concentration of MoS2NPs in the T1 treatment group had the greatest effect on the soluble solids content of tomato fruit. As the concentration increased, the soluble solids content of tomato fruit did not change much.

[0099] 3 Discussions

[0100] This study systematically investigated the regulatory effects of exogenous spraying of different concentrations of MoS2 NPs on tomato plant growth and fruit quality. Results showed that low concentrations of MoS2 nanoparticles (T1: 0.025 mg / mL, T2: 0.050 mg / mL) significantly increased plant height and stem diameter, likely due to the nanoparticles' efficient absorption properties. When the concentration was increased to T4 (0.100 mg / mL), the beneficial effects on plant height and stem diameter weakened or even disappeared, suggesting that high concentrations of nanoparticles may cause oxidative stress in plants.

[0101] In terms of chlorophyll content, the T3 treatment (0.075 mg / mL) showed the highest increase (62.46%), which may be due to the fact that molybdenum, as a cofactor of nitrate reductase, directly promotes nitrogen metabolism and chloroplast development. At the same time, the sulfur component in MoS2 may further enhance the antioxidant capacity of leaves and delay chlorophyll degradation by enhancing glutathione synthesis. It is worth noting that the chlorophyll content of the high-concentration treatment (T4) was still significantly higher than that of the control, but the increase was lower than that of T3, indicating that there may be a threshold for the dosage effect of nanoparticles, and excessive application may interfere with the activity of the photosystem.

[0102] In terms of fruit quality, the vitamin C content of the T2 treatment increased by 33.76%, and the soluble sugar content increased by 53.00%, which were significantly better than the other treatments. This result may be related to the synergistic effect of molybdenum-sulfur: the synthesis of molybdenum cofactor (Moco) depends on sulfur supply, and sulfur is involved in the activation of key enzymes related to sugar metabolism, thereby promoting the accumulation of soluble sugars. In addition, the ROS signaling pathway induced by nanoparticles may have stimulated the secondary metabolic response of the plant, leading to increased synthesis of ascorbic acid. However, soluble solids were significantly increased only in the T1 treatment, indicating that there are differences in the effects of nano-molybdenum fertilizer on different quality indicators.

[0103] This study systematically revealed for the first time the regulatory effects of MoS2 nanoparticles on trace element absorption in tomatoes. Spraying MoS2 significantly increased the accumulation of Mo, S, and Fe in leaves and roots. In particular, the Mo content in leaves treated with T4 increased by 181.48% compared with the control, which is closely related to the sulfur-molybdenum synergistic energy supply characteristics of MoS2. However, the high-concentration treatment (T4) showed an inhibitory effect on Zn absorption, which may be due to ion competition effects or interference of nanoparticles with the rhizosphere microbial community. This finding suggests that in practical applications, the balance of different trace elements should be comprehensively considered to avoid nutritional imbalance caused by excessive amounts of a single element.

[0104] 4 Conclusion

[0105] This study identified the optimal spray concentration of MoS2 nanoparticles as 0.050-0.075 mg / mL. Spraying 0.050 mg / mL (T2) of MoS2 nanoparticles significantly increased tomato plant height (22.34%) and stem diameter (5.16%), making it the optimal concentration for promoting robust plant growth. Treatment with 0.075 mg / mL (T3) had the greatest effect on increasing chlorophyll content (62.46%), indicating that this concentration effectively enhances tomato photosynthetic capacity. Treatment with 0.050 mg / mL (T2) significantly increased fruit vitamin C (33.76%) and soluble sugar content (53.00%), making it a recommended option for improving flavor quality. MoS2 nanoparticles significantly promote the absorption of Mo, S, and Fe through a sulfur-molybdenum synergistic effect, but high concentrations (≥0.100 mg / mL) may inhibit Zn accumulation, necessitating the application of zinc fertilizers for nutritional balance.

[0106] In summary, foliar spraying of 0.050-0.075 mg / mL MoS2 nanoparticles can promote both growth and quality of tomatoes, providing a theoretical basis for the agricultural application of nano-molybdenum fertilizers.

[0107] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. Application of molybdenum disulfide nanoparticles in the preparation of tomato foliar fertilizer.

2. Application of molybdenum disulfide nanoparticles in promoting tomato plant growth and / or improving fruit quality, characterized in that: The molybdenum disulfide nanoparticles are applied to tomato plants via foliar spraying.

3. The application according to claim 2, characterized in that: The promoting of tomato plant growth includes increasing plant height and stem thickness; and the improving of fruit quality includes increasing one or more of the following: increasing the vitamin C content of the fruit, increasing the soluble sugar content of the fruit, and increasing the soluble solid content of the fruit.

4. The application of molybdenum disulfide nanoparticles in increasing chlorophyll content is characterized in that: The molybdenum disulfide nanoparticles are applied to tomato plants via foliar spraying.

5. Use of molybdenum disulfide nanoparticles in increasing the trace element content, Mo content and / or S content of tomato plants, characterized in that: The molybdenum disulfide nanoparticles are applied to tomato plants via foliar spraying.

6. The application according to claim 5, characterized in that: The trace elements include one or more of Fe, Mn, Cu and Zn.

7. A method for improving tomato plant growth and fruit quality, characterized in that: When the tomato seedlings grow to the five-leaf stage, the molybdenum disulfide nanoparticles according to claim 1 are sprayed on the leaves.

8. The method according to claim 7, characterized in that: The concentration range of the molybdenum disulfide nanoparticles is 0.025-0.100 mg / mL.

9. The method according to claim 7, characterized in that: The spraying amount of the molybdenum disulfide nanoparticles per tomato plant is 0.4 mL each time; starting from the first spraying, spray once every 5 days, for a total of 5 spraying times.

10. The method according to claim 7, characterized in that: When spraying on leaves, be sure to spray evenly on both sides of the leaves until the leaves are filled with spray droplets.

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