Application of sodium selenite in preventing and / or alleviating sunscald of tea tree

Abstract

The application belongs to the technical field of tea tree planting, and particularly relates to application of sodium selenite in prevention and / or alleviation of tea tree sunscald. The application provides application of sodium selenite in prevention and / or alleviation of tea tree sunscald. Specifically, by applying sodium selenite on tea trees, the sunscald of tea trees is prevented and / or alleviated, the damage of high-temperature and dry weather to tea trees is avoided, and the loss caused by sunscald is reduced. The method for preventing and / or alleviating tea tree sunscald by using sodium selenite is simple in operation and high in efficiency. Compared with the existing methods such as shading, reasonable close planting, soil tillage, drought prevention and timely irrigation, the economic and labor costs are both lower, and tea farmers can obtain higher benefits.

Description

Technical Field

[0001] This invention belongs to the field of tea tree cultivation technology, specifically relating to the application of sodium selenite in preventing and / or alleviating sunburn in tea trees. Background Technology

[0002] Sunburn is a physiological disorder, which can be classified into browning type, sunburn type, and photo-oxidative type sunburn according to the severity of plant damage. High temperature and strong light are the main causes of sunburn in plants. Sunburn causes significant changes in the content of soluble substances, malondialdehyde, antioxidant enzymes, chlorophyll, and carotenoids in plant fruits and leaves, resulting in browning on the surface of fruits and leaves, reducing fruit yield and quality. For tea trees, sunburn causes discoloration of tea leaves, reduces tea quality, and in severe cases, can cause large-scale death of tea trees, reduced tea yield, reduced tea garden production, and a sharp decline in the economic benefits for tea farmers. Compared to green tea varieties, light-sensitive yellowing varieties are more prone to sunburn.

[0003] In the past, the main methods for preventing and alleviating sunscald on tea trees included the following: 1) Shading and reasonable dense planting: Building shade structures / nets in the tea garden or interplanting with tall trees can effectively prevent sunscald; 2) Pre-drought prevention: Deep plowing and applying sufficient base fertilizer for tea gardens before closing the garden in winter can improve drought resistance and the ability to resist sunscald; 3) Timely irrigation: In the dry season, watering should be done in a timely manner as needed to ensure normal transpiration of the leaves, which can effectively prevent sunscald; 4) Promoting root activity and strengthening the plants through soil cultivation can also prevent sunscald to a certain extent.

[0004] However, while the above methods can prevent and alleviate sunburn on tea trees to some extent, they are all complicated to operate and consume a lot of economic and labor costs, which greatly reduces the income of tea farmers and results in less overall benefit. Summary of the Invention

[0005] The purpose of this invention is to provide the application of sodium selenite in the prevention and / or relief of sunburn on tea trees. By applying sodium selenite to tea trees, the effect of preventing and / or relieving sunburn on tea trees can be achieved. Moreover, this method is simple to operate, highly efficient, and has low labor and economic costs, resulting in high benefits for tea farmers.

[0006] This invention provides the application of sodium selenite in the prevention and / or relief of sunburn in tea trees.

[0007] Preferably, the sodium selenite is used in the form of a sodium selenite solution, wherein the concentration of the sodium selenite solution is 1.0 to 4.0 mg / L.

[0008] Preferably, the sodium selenite is applied by foliar spraying.

[0009] The present invention also provides a method for preventing and / or alleviating sunscald on tea trees, comprising the following steps:

[0010] Sodium selenite is applied to tea plants.

[0011] Preferably, the sodium selenite is applied in the form of a sodium selenite solution, wherein the concentration of the sodium selenite solution is 1.0 to 4.0 mg / L.

[0012] Preferably, the application method includes foliar spraying.

[0013] Preferably, the foliar spraying frequency is once a day for 3 to 5 consecutive days.

[0014] Preferably, the amount sprayed each time is based on the amount of liquid dripping from the tea leaves.

[0015] Preferably, when spraying the leaves, the vertical distance between the nozzle and the surface of the tea leaves is 3 to 5 cm.

[0016] Preferably, the application period includes 5 to 7 days before the occurrence of high-temperature weather, where the daily maximum temperature during the high-temperature weather is at least 34°C.

[0017] Beneficial effects:

[0018] This invention provides the application of sodium selenite in the prevention and / or mitigation of sunscald in tea trees. Specifically, it involves applying sodium selenite to tea trees to prevent and / or mitigate sunscald, avoiding damage caused by high temperatures and drought, and reducing losses due to sunscald. The method described in this invention for preventing and / or mitigating sunscald in tea trees using sodium selenite is simple to operate and highly efficient. Compared with existing methods involving shading, appropriate planting density, soil cultivation, drought prevention, and timely irrigation, it has lower economic and labor costs, allowing tea farmers to obtain higher profits. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly described below.

[0020] Figure 1 Phenotypic images of tea plants treated with different concentrations of exogenous selenium under sunburn conditions in Example 1;

[0021] Figure 2 The value represents the malondialdehyde (MDA) content in tea plants treated with exogenous selenium under sun-scalding conditions in Example 2. Detailed Implementation

[0022] This invention provides the application of sodium selenite in the prevention and / or relief of sunburn in tea trees.

[0023] In this invention, the sodium selenite is preferably used in the form of a sodium selenite solution, the concentration of which is preferably 1.0–4.0 mg / L, more preferably 2.0–3.0 mg / L, and even more preferably 3.0 mg / L. This invention does not impose any particular limitation on the preparation method of the sodium selenite solution; conventional methods in the art can be used to prepare a sodium selenite solution of the corresponding concentration. The preferred application method of the sodium selenite in this invention includes foliar spraying.

[0024] Specifically, the present invention also provides a method for preventing and / or alleviating sunburn on tea trees, comprising the following steps: applying sodium selenite to the tea trees.

[0025] In this invention, the sodium selenite is applied in the form of a sodium selenite solution, the concentration of which is 1.0–4.0 mg / L, more preferably 2.0–3.0 mg / L, and even more preferably 3.0 mg / L. The preferred method of application is foliar spraying, preferably once a day for 3–5 consecutive days, more preferably 4 days; the amount sprayed each time is preferably enough to cause droplets to fall from the tea leaves. During foliar spraying, the vertical distance between the nozzle and the surface of the tea leaves is 3–5 cm. Foliar spraying is preferably performed between 7–9 am or 4–6 pm to avoid reducing the spraying effect at midday.

[0026] In this invention, the application of sodium selenite is preferably carried out 5 to 7 days before the onset of high-temperature weather, more preferably 6 days before the onset of high-temperature weather; the daily maximum temperature during the high-temperature weather is preferably at least 34°C. The daily maximum temperature mentioned in this invention is preferably based on weather forecasts.

[0027] This invention prevents and / or alleviates sunscald on tea trees by applying sodium selenite, avoiding damage caused by high temperatures and drought, and reducing losses due to sunscald. The method of preventing and / or alleviating sunscald on tea trees using sodium selenite described in this invention is simple to operate and highly efficient. It demonstrates the simplicity and feasibility of the method described in this invention; compared with existing methods that rely on shading, reasonable planting density, soil cultivation, drought prevention, and timely irrigation, it has lower economic and labor costs, allowing tea farmers to obtain higher profits.

[0028] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the accompanying drawings and embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0029] Example 1

[0030] A method for preventing and / or alleviating sunburn in tea trees, comprising the following steps:

[0031] Experimental site: Artificial climate chamber, Anhui Agricultural University;

[0032] Experimental subject: 'Golden Leaf' tea tree variety;

[0033] Experimental procedure:

[0034] 1. Material collection: The test material was the tea variety 'Golden Leaf'. The tea seedlings were uniform in growth, healthy and free from disease, and about 30cm in height.

[0035] 2. Preparation of Na2SeO3 treatment solutions of different concentrations: Take 1.0, 2.0, 3.0, and 4.0 mg of sodium selenite crystal powder and dissolve them in 1 L of pure water (final concentrations are 1.0, 2.0, 3.0, and 4.0 mg / L, respectively).

[0036] 3. Seedling Cultivation: Plant the purchased tea seedlings in 20cm diameter flowerpots. The volume ratio of nutrient soil, vermiculite, and perlite should be 2:1:1. Growing environment: temperature 28℃, humidity 80%, light intensity 500μmol·m⁻². -2 ·s -1 ;

[0037] 4. Sunburn resistance test of different concentrations of selenium: Select tea seedlings with similar growth and spray them with sodium selenite solution at concentrations of 0, 1.0, 2.0, 3.0 and 4.0 mg / L at a distance of 3-5 cm from the leaves until the leaves drip off. Spray once a day for 4 consecutive days; the control group was sprayed with an equal amount of water.

[0038] Two days after the exogenous treatment ended, the tea seedlings were placed in an artificial climate chamber at a temperature of 34℃, a humidity of 60%, and a light intensity of 1600 μmol·m⁻². -2 ·s -1 Simulated sunburn treatment was performed, and after 4 hours of treatment, observations, photographs, and statistics were collected.

[0039] 5. Experimental Results:

[0040] Effects of different concentrations of selenium on the apparent morphology of tea plants under sunburn conditions: such as Figure 1 As shown, compared with the selenium-treated group, the water-treated group had the most sun-scorched leaves and the largest lesion area. Among the four spray concentrations, the number of sun-scorched tea leaves and the lesion area showed a trend of first decreasing and then increasing with increasing exogenous selenium concentration, with the 3.0 mg / L concentration resulting in the fewest sun-scorched leaves and the smallest lesion area. The results indicate that exogenous application of sodium selenite can indeed alleviate the degree of sunscorch in tea trees, with the 3.0 mg / L Na2SeO3 solution showing the best effect.

[0041] The effects of different concentrations of selenium on the disease index of tea tree sunburn are shown in Table 1. The number of leaves at each disease level was counted according to the degree of susceptibility, and the average incidence rate and disease index were calculated according to the formula to determine the severity of the disease on the leaves of tea trees. The grading standards for tea tree sunburn are shown in Table 2. Incidence rate = number of diseased leaves / total number of leaves investigated × 100%, disease index = [∑(number of leaves at each disease level × representative value of that disease level) / (total number of leaves investigated × highest level representative value)] × 100, control effect (%) = [(disease index of control group - disease index of treatment group) / disease index of control group] × 100%.

[0042] Table 1. Effects of different selenium concentrations on the severity index of sunburn in tea trees.

[0043]

[0044] Note: Different letters in the table indicate significant differences (P < 0.05).

[0045] Table 2 Grading Standards for Tea Tree Sunburn

[0046]

[0047] Table 1 shows that, compared with the untreated group, the incidence of sunburn in tea trees under sunscald conditions was reduced by 33.83%, 29.62%, 78.14%, and 9.84% respectively when selenium concentrations were 1.0, 2.0, 3.0, and 4.0 mg / L. The control effects were 42.61%, 42.61%, 89.38%, and 17.58% respectively. The results indicate that exogenous spraying of 3.0 mg / L sodium selenite resulted in the lowest incidence of sunburn and the best prevention effect against sunburn in tea trees.

[0048] Example 2

[0049] A method for preventing and / or alleviating sunburn in tea trees, comprising the following steps:

[0050] Experimental site: Artificial climate chamber, Anhui Agricultural University;

[0051] Experimental subject: 'Golden Leaf' tea tree variety;

[0052] 1. Material collection: The test material was the tea variety 'Golden Leaf'. The tea seedlings were uniform in growth, healthy and free from disease, and about 30cm in height.

[0053] 2. Preparation of Na2SeO3 treatment solution: Take 3.0 mg of sodium selenite crystal powder and dissolve it in 1 L of pure water (concentration is 3.0 mg / L).

[0054] 3. Seedling growth environment: Plant the purchased tea seedlings in flower pots with a diameter of 20cm. The volume ratio of nutrient soil, vermiculite and perlite is 2:1:1. Then place them in a glass greenhouse.

[0055] Normal growth environment: temperature 28℃, humidity 80%, light intensity 500 μmol·m -2 ·s -1 ;

[0056] Simulated sunscald environment: temperature 34℃, humidity 60%, light intensity 1600 μmol·m -2 ·s -1 .

[0057] 4. Simulation of sunburn and no sunburn after spraying sodium selenite: A 3 mg / L sodium selenite aqueous solution was sprayed and placed in normal growth environment and simulated sunburn environment, respectively.

[0058] The experimental groups were Se (no sunburn after treatment with 3 mg / L Na2SeO3) and SeH (sunburn after treatment with 3 mg / L Na2SeO3);

[0059] The control groups were CK (no sunburn after water treatment) and CKH (sunburn after water treatment). The control groups were sprayed with the same amount of water as the experimental groups.

[0060] The test results are as follows:

[0061] The effect of exogenous selenium on malondialdehyde (MDA) content in tea plants under sun-scalding conditions is as follows: Figure 2 As shown. The method for determining malondialdehyde (MDA) is as follows:

[0062] After sun-scalding for 4 hours, 0.5g samples of the 3rd and 4th mature leaves of tea trees were collected in a mortar and ground with 5mL of 5% (v / v) trichloroacetic acid. The leaves were ground into a paste and collected in centrifuge tubes, then centrifuged at 4000 rpm for 10 min at room temperature. 2mL of the supernatant was collected in a centrifuge tube, and 3mL of 0.5% (m / v) thiobarbituric acid was added, followed by gentle shaking for 15 seconds. Pure water was used as a control group. The mixed solution was heated in a water bath at 100℃ for 15 min. After rapid cooling, the solution was centrifuged at 4000 rpm for 10 min. The supernatant was then analyzed at 523nm, 600nm, and 450nm using a UV spectrophotometer. Data were recorded and calculated. The calculation formula is as follows: MDA content (μmol·g) -1 )=[6.45×(OD 532 -OD 600 -0.56×OD 450 The formula is: (V × V / 1000W) where V = extraction liquid volume (mL); W = sample fresh weight (g).

[0063] like Figure 2The results showed that, under conditions of no sunscald growth after selenium spraying, the MDA content in the selenium-treated group was significantly lower than that in the control group, decreasing by 22.14%. Under conditions of sunscald, the MDA content in the selenium-treated group was significantly lower than that in the water-treated group, decreasing by 19.89%. These results indicate that exogenous application of sodium selenite, regardless of whether high temperature and drought occurred, can reduce the accumulation of MDA in tea leaves. This suggests that spraying sodium selenite on tea seedlings helps to enhance the tea tree's resistance to high temperature and drought stress. Furthermore, it demonstrates that even without high temperature and drought after sodium selenite spraying, there is no negative impact on the tea tree.

[0064] The above examples demonstrate that exogenous application of sodium selenite can effectively prevent and alleviate sunburn in tea trees, and is highly operable and easy to implement.

[0065] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preventing and / or alleviating sunburn in tea trees, characterized in that, Includes the following steps: Sodium selenite solution was applied to the tea plants by foliar spraying, wherein the concentration of sodium selenite solution was 3.0 mg / L.

2. The method according to claim 1, characterized in that, The foliar spraying frequency is once a day for 3 to 5 consecutive days.

3. The method according to claim 2, characterized in that, The amount of liquid sprayed each time should be such that droplets fall from the tea leaves.

4. The method according to claim 1, characterized in that, When spraying the leaves, the vertical distance between the nozzle and the surface of the tea leaves is 3-5 cm.

5. The method according to any one of claims 1 to 4, characterized in that, The application period includes 5 to 7 days before the occurrence of high-temperature weather, where the daily maximum temperature is at least 34°C.

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