Method for preventing and treating tomato blossom-end rot based on brassinolide

Abstract

The invention belongs to the technical field of tomato disease prevention and treatment, and particularly relates to a method for preventing and treating tomato blossom-end rot based on brassinolide, which comprises the following steps: S1, seedling raising is performed on tomato seeds by adopting substrate turf in a seedling raising period; s2, performing field planting when the tomatoes grow to a three-leaf one-core period, performing field planting in a totally-closed circulating cultivation tank filled with vermiculite, and then performing irrigation with a total nutrient solution; s3, after the tomatoes are planted for one month, when the diameter of a first spike fruit grows to 3-4 cm, spraying an aqueous solution of brassinolide to the leaf surfaces of the tomato plants. According to the method, by spraying the exogenous brassinolide, the utilization efficiency of fruits on calcium can be improved, the content of calcium needing to be applied in soil is reduced, the morbidity of the tomato blossom-end rot is reduced, and meanwhile, the soil structure is prevented from being damaged by excessive calcium elements.

Description

Technical Field

[0001] The invention belongs to the technical field of tomato disease prevention and control, and particularly relates to a method for preventing and controlling tomato navel rot based on brassinolide. Background Art

[0002] Tomato navel rot is a serious disease in tomato cultivation, typically occurring during the young fruit stage. Initially, it manifests as water-soaked lesions on the navel of the tomato, which gradually expand, causing the top of the fruit to appear grayish-white and rotten, followed by a sunken appearance due to water loss. Tomato navel rot is primarily caused by the plant's inability to absorb sufficient calcium from the soil, leading to physiological disturbances in the navel cells and a loss of water control, leading to the disease.

[0003] At present, in order to prevent and control tomato navel rot, calcium fertilizer is usually applied during the growth of tomatoes to increase the tomato's absorption of calcium, thereby reducing the incidence of tomato navel rot.

[0004] However, in actual operation, it was found that tomatoes have limited ability to absorb calcium. When the calcium concentration in the soil is low, they cannot absorb calcium in the soil. Therefore, it is necessary to increase the proportion of calcium fertilizer in the fertilizer. However, as the proportion of calcium fertilizer increases, excessive calcium ions will combine with other ions to form insoluble calcium salts, resulting in increased soil compaction and poor air permeability, which affects the plant's absorption of other nutrients in the soil and fertilizer. Summary of the Invention

[0005] In order to solve the problems existing in the above-mentioned prior art, the present invention provides a method for preventing and controlling tomato navel rot based on brassinolide. By spraying exogenous brassinolide, the calcium utilization efficiency of the fruit can be improved, the required calcium content in the soil can be reduced, the incidence of tomato navel rot can be reduced, and the soil structure can be prevented from being damaged by excessive calcium.

[0006] The specific technical solution adopted in the present invention is:

[0007] A method for preventing and controlling tomato navel rot based on brassinolide, comprising the following steps:

[0008] S1, using substrate peat to grow tomato seeds during the seedling stage;

[0009] S2. When the tomatoes have grown to the three-leaf and one-heart stage, they are planted in a fully enclosed circulation cultivation tank filled with vermiculite and then watered with a complete nutrient solution;

[0010] S3. One month after planting tomatoes, when the diameter of the first bunch of fruits grows to 3-4 cm, spray the leaves of the tomato plants with an aqueous solution of brassinolide;

[0011] The complete nutrient solution contains calcium ions, and the concentration of calcium ions is 450-500 mg / L.

[0012] Furthermore, the ingredients of the complete nutrient solution include:

[0013] 450-500mg / L Ca(NO3)2·4H2O,

[0014] 300-310mg / L KNO3,

[0015] 55-60mg / L NH4H2PO4,

[0016] 240-250mg / L MgSO4·7H2O,

[0017] 17.5-22.5mg / L NaFe-EDTA,

[0018] 2.5-3mg / L H3BO3,

[0019] 2-2.4mg / L MnSO4·4H2O,

[0020] 0.2-0.25mg / L ZnSO4·7H20,

[0021] 0.05-0.1mg / L CuSO4·5H20,

[0022] 0.01-0.03mg / L(NH4)6Mo7O 24 4H2O;

[0023] The iron content in NaFe-EDTA is 12.0-15.0%.

[0024] Furthermore, the concentration of the brassinolide aqueous solution is 0.025-0.4 mg / L.

[0025] Furthermore, the complete nutrient solution is watered 4 times a day, with each watering lasting 15-20 minutes.

[0026] Furthermore, the cycle of spraying the aqueous solution of brassinolide on the leaves of the tomato plants in step S3 is: spraying the aqueous solution of brassinolide on the leaves of the tomato plants once every 3-4 days, and spraying continuously for 7-9 times, each spraying until water droplets appear on the leaves of the entire tomato plant.

[0027] The beneficial effects of the present invention are:

[0028] 1. The present invention improves the absorption and utilization efficiency of calcium by fruits by spraying exogenous brassinolide. Even if the concentration of calcium fertilizer in the soil is low, tomatoes can still absorb the calcium therein, thereby reducing the occurrence of tomato navel rot. Therefore, there is no need to apply a large amount of calcium fertilizer. Under the premise of ensuring the healthy growth of tomato plants, damage to the soil caused by a large amount of calcium fertilizer is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The effect of different concentrations of BR on the incidence of blossom end rot under calcium deficiency;

[0030] Figure 2 Photos of tomato plants were taken on day 40 for different treatments;

[0031] Figure 3 The incidence statistics of tomato plants with different treatments at 20-40 days;

[0032] Figure 4 is the incidence of navel rot in tomato plants under different treatments;

[0033] Figure 5 The effect of exogenous BR on calcium ion content in different parts of tomatoes;

[0034] Figure 6 Effects of exogenous BR on the content of endogenous hormones in tomato leaves. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0036] The tomato variety used is "Nongbofen 18109". 1. Specific embodiments

[0038] Example 1

[0039] S1, using substrate peat to grow tomato seeds during the seedling stage;

[0040] S2. When the tomatoes have grown to three leaves and one heart, they are transplanted into a fully enclosed circulation cultivation tank filled with vermiculite. They are watered with full nutrient solution four times a day for 20 minutes each time, ensuring that there is water backflow.

[0041] S3. Planting was done on April 14. On May 11, when the diameter of the first ear of fruit grew to 3-4 cm, the leaves of the tomato plants were sprayed with an aqueous solution of brassinolide. Thereafter, the spraying was repeated every 3 days for 9 times.

[0042] The concentration of the brassinolide aqueous solution is 0.025 mg / L.

[0043] Example 2

[0044] The only difference between Example 2 and Example 1 is that the concentration of the aqueous solution of brassinolide in Example 2 is 0.05 mg / L.

[0045] Example 3

[0046] The only difference between Example 3 and Example 1 is that the concentration of the aqueous solution of brassinolide in Example 3 is 0.075 mg / L.

[0047] Example 4

[0048] The only difference between Example 4 and Example 1 is that the concentration of the aqueous solution of brassinolide in Example 4 is 0.1 mg / L.

[0049] Example 5

[0050] The only difference between Example 5 and Example 1 is that the concentration of the aqueous solution of brassinolide in Example 5 is 0.15 mg / L.

[0051] Example 6

[0052] The only difference between Example 6 and Example 1 is that the concentration of the aqueous solution of brassinolide in Example 6 is 0.2 mg / L.

[0053] Example 7

[0054] The only difference between Example 7 and Example 1 is that the concentration of the aqueous solution of brassinolide in Example 7 is 0.4 mg / L.

[0055] Comparative Example 1

[0056] The only difference between Comparative Example 1 and Example 4 is that the aqueous solution of brassinolide is replaced with clean water in Comparative Example 1. The specific steps of Comparative Example 1 are as follows:

[0057] S1, using substrate peat to grow tomato seeds during the seedling stage;

[0058] S2. When the tomatoes have grown to three leaves and one heart, they are transplanted into a fully enclosed circulation cultivation tank filled with vermiculite. They are watered with full nutrient solution four times a day for 20 minutes each time, ensuring that there is water backflow.

[0059] S3. Plant on April 14. On May 11, when the diameter of the first bunch of fruits grows to 3-4 cm, spray the leaves of the tomato plants with clean water, and then spray once every 3 days for 9 consecutive times.

[0060] Comparative Example 2

[0061] The difference between Comparative Example 2 and Example 4 is that the nutrient solution in Comparative Example 2 does not contain calcium, and the brassinolide aqueous solution is replaced with clean water. The specific steps of Comparative Example 2 are as follows:

[0062] S1, using substrate peat to grow tomato seeds during the seedling stage;

[0063] S2. When the tomatoes have grown to three leaves and one heart, they are transplanted into a fully enclosed circulation cultivation tank filled with vermiculite. They are watered with calcium-deficient nutrient solution four times a day for 20 minutes each time, ensuring that there is water backflow.

[0064] S3. Plant on April 14. On May 11, when the diameter of the first bunch of fruits grows to 3-4 cm, spray the leaves of the tomato plants with clean water, and then spray once every 3 days for 9 consecutive times.

[0065] Comparative Example 3

[0066] The only difference between Comparative Example 3 and Example 4 is that the nutrient solution in Comparative Example 3 does not contain calcium. The specific steps of Comparative Example 1 are as follows:

[0067] S1, using substrate peat to grow tomato seeds during the seedling stage;

[0068] S2. When the tomatoes have grown to three leaves and one heart, they are transplanted into a fully enclosed circulation cultivation tank filled with vermiculite. They are watered with calcium-deficient nutrient solution four times a day for 20 minutes each time, ensuring that there is water backflow.

[0069] S3. Planting was done on April 14. On May 11, when the diameter of the first ear of fruit grew to 3-4 cm, the leaves of the tomato plants were sprayed with an aqueous solution of brassinolide. Thereafter, the spraying was repeated every 3 days for 9 times.

[0070] The concentration of the brassinolide aqueous solution is 0.1 mg / L.

[0071] The ingredients of the nutrient solution in the embodiment and the comparative example are as follows:

[0072] Table 1

[0073]

[0074] 2. Performance Testing

[0075] 1. Screening results of suitable concentration of brassinolide

[0076] In order to explore the effect of different concentrations of brassinolide on the incidence of tomato navel rot under calcium deficiency, the incidence of tomato navel rot under calcium deficiency was studied with different concentration gradients of brassinolide. The initial comparative example 1 was recorded as CK, and examples 1-7 were recorded as N1-N7 respectively. The test results are shown in FIG. Figure 1 .

[0077] Compared with the treatment of complete calcium deficiency and spraying with water, the incidence of navel rot showed a trend of first decreasing and then increasing with the increase of BR concentration, reaching the minimum value at 0.1 mg / L. Therefore, the optimal BR concentration was determined to be 0.1 mg / L.

[0078] 2. Incidence of navel rot in tomato fruits under different treatments

[0079] The incidence of navel rot was calculated as the percentage of navel rot fruits in the third and fourth ears of 13 tomato plants in the same treatment to the total number of fruits in all third and fourth ears.

[0080] The tomato culture was treated by the treatment methods of Example 4 and Comparative Examples 1-3, and the tomatoes were observed under different treatments. The incidence of navel rot was counted every 2 days. Example 4 was recorded as (+Ca)BR; Comparative Example 1 was recorded as (+Ca)CK; Comparative Example 2 was recorded as (-Ca)CK; Comparative Example 3 was recorded as (-Ca)BR. The incidence is shown in Table 1. Figure 2 .

[0081] It can be seen Figure 2 In the photos corresponding to (+Ca)CK and (+Ca)BR, the tomatoes grow more vigorously, while in the photos corresponding to (-Ca)CK and (-Ca)BR, the tomato leaves are relatively sparse (the brighter colors in the photos corresponding to (-Ca)CK and (-Ca)BR are due to light issues).

[0082] Among them, no navel rot was found under the full nutrient solution treatment regardless of whether brassinolide was sprayed on the leaves. However, in actual production, tomatoes are prone to calcium deficiency and are not easy to detect. Therefore, it is necessary to apply brassinolide to prevent and control navel rot.

[0083] The incidence rate of (-Ca)CK treatment continued to rise from day 20 to day 50, reached a high value on day 40, and then stabilized. Therefore, the incidence rate was taken as the sampling point for this experiment, and the results are shown in Figure 3 The incidence of navel rot was 0 in both (+Ca)CK and (+Ca)BR treatments, and the two straight lines in the figure overlap.

[0084] Compared with the (-Ca)CK treatment, the (-Ca)BR treatment significantly reduced the incidence of navel rot. Therefore, exogenous spraying of brassinolide (0.1 mg / L) can reduce the incidence of tomato navel rot caused by calcium deficiency. The results are shown in Figure 4 The results of this study showed that the use of brassinolide can reduce the incidence of tomato navel rot, mainly because brassinolide improves the efficiency of calcium utilization in the fruit.

[0085] 3. Determination results of calcium ion content in tomato plants under different treatments

[0086] 3.1. Calcium content determination method

[0087] To explore the effect of exogenous brassinolide on Ca 2+ To investigate the effect of Ca content on the tomato plant, we selected tomato samples on the 40th day after treatment. We used mixed sampling of multiple plants, pulled the whole tomato plant out of the substrate tank, cut the roots, stems, leaves, and fruits, placed them in kraft paper bags, and weighed the fresh weight. The plants were then dried in an oven at 75°C and then dried at 105°C to constant weight. The Ca content in different parts of the tomato (roots, stems, leaves, and fruits) was measured using a ZEEnit-700P atomic absorption spectrophotometer. 2+ concentration.

[0088] 3.2 Calcium ion content in different parts of tomato plants under different treatments

[0089] To investigate the effect of exogenous brassinolide on the distribution of calcium ions in different parts of tomatoes, the calcium ion content in roots, stems, leaves and fruits was determined. Figure 5 .

[0090] Compared with water spraying, exogenous brassinolide spraying reduced calcium content in roots and stems by 24.69% and 8.33%, respectively, under full nutrient solution conditions. In leaves and fruits, exogenous brassinolide spraying increased calcium content by 4.88% and 105.19%, respectively, indicating that exogenous brassinolide spraying promoted the transfer of calcium ions from roots and stems to leaves and fruits, with a higher transfer to fruits. Under calcium deficiency conditions, exogenous brassinolide spraying increased calcium content in roots, stems, leaves, and fruits by 11.26%, 127.15%, 40.39%, and 16.15%, respectively, indicating that exogenous brassinolide spraying promoted calcium absorption.

[0091] 4. Determination results of endogenous hormone content in tomato plants with different treatments

[0092] 4.1. Determination of endogenous hormone content

[0093] Acetonitrile was used as the sample extract to extract each hormone, and the content of each hormone was determined and analyzed by high performance liquid chromatography tandem mass spectrometry (HPLC-MS / MS) using a Poroshell 120SB-C18 reverse phase chromatography column (2.1×150, 2.7 μm) and a Qtrap 6500 mass spectrometer.

[0094] The specific steps are as follows: grind 1.5g of plant material with liquid nitrogen, add extraction buffer (15ml of acetonitrile, 4μl of internal standard mother liquor) and mix well, extract overnight at 4℃, centrifuge at 4℃ and 12000g for 5min, and collect the supernatant. Add 5 times the volume of acetonitrile to the precipitate and repeat the extraction twice. Then add 35mg of C18 filler, centrifuge at 10000g for 5min, and collect the supernatant. Blow dry the supernatant with nitrogen and redissolve it with 400μl of methanol. Filter the dissolved solution with 0.22μm water membrane, store at -20℃, and finally use HPLC-MS / MS to detect the hormone content.

[0095] 4.2 Endogenous hormone content in tomato plants under different treatments

[0096] Hormone content in tomato leaves under different treatments Figure 6 As shown, under full nutrient solution conditions, compared with spraying water, exogenous spraying of brassinolide increased the TZR content and reduced the GA3, SA, IAA, ABA, and JA contents, indicating that spraying brassinolide stimulated cell differentiation and rapid plant growth; under calcium deficiency conditions, compared with spraying water, exogenous spraying of brassinolide increased the IAA, ABA, and JA contents and reduced the TZR, GA3, and SA contents.

Claims

1. A method for controlling tomato navel rot based on brassinolide, characterized in that: The following steps are involved: S1, using substrate peat to grow tomato seeds during the seedling stage; S2. When the tomatoes grow to the three-leaf and one-heart stage, they are planted in a fully enclosed circulation cultivation tank filled with vermiculite, and then watered with a complete nutrient solution; S3. One month after planting tomatoes, when the diameter of the first ear of fruit grows to 3-4 cm, spray the leaves of the tomato plants with an aqueous solution of brassinolide; Wherein, the complete nutrient solution contains calcium ions, and the concentration of calcium ions is: 450-500 mg / L.

2. The method for controlling tomato navel rot based on brassinolide according to claim 1, characterized in that: The ingredients of the complete nutrient solution include: 450-500mg / L Ca(NO3)2·4H2O, 300-310mg / L KNO3, 55-60mg / L NH4H2PO4, 240-250mg / L MgSO4·7H2O, 17.5-22.5mg / L NaFe-EDTA, 2.5-3mg / L H3BO3, 2-2.4mg / L MnSO4·4H2O, 0.2-0.25mg / L ZnSO4·7H20, 0.05-0.1mg / L CuSO4·5H20, 0.01-0.03mg / L(NH4)6Mo7O 24 ·4H2O; The iron content in NaFe-EDTA is 12.0-15.0%.

3. The method for controlling tomato navel rot based on brassinolide according to claim 1, characterized in that: The concentration of the aqueous solution of brassinolide is 0.025-0.4 mg / L.

4. The method for controlling tomato navel rot based on brassinolide according to claim 1, characterized in that: The complete nutrient solution was used for watering 4 times a day, and each watering lasted 15-20 minutes.

5. The method for controlling tomato navel rot based on brassinolide according to claim 1, characterized in that: The cycle of spraying the aqueous solution of brassinolide on the leaves of the tomato plants in step S3 is: spraying the aqueous solution of brassinolide on the leaves of the tomato plants once every 3-4 days, and spraying continuously for 7-9 times, each spraying until water droplets appear on the leaves of the entire tomato plant.

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