Wheat unmanned aerial vehicle leaf surface spraying selenium fertilizer limiting method based on yield level

Abstract

The invention discloses a wheat unmanned aerial vehicle foliage spraying selenium fertilizer quantity limiting method based on the yield level, belongs to the technical field of agricultural fertilization, and aims at solving the problem that in the prior art, the selenium fertilizer quantity is not limited when an unmanned aerial vehicle is used for applying selenium fertilizer, and the human body is affected by excessive or insufficient selenium fertilizer. Acquiring wheat grain selenium content and soil effective selenium content data; comparing the selenium content of the wheat grains with the effective selenium content of the soil; when the selenium content of the wheat grains and the effective selenium content of the soil are both lower than a preset threshold value, the unmanned aerial vehicle sprays selenium fertilizer on leaf surfaces; otherwise, the unmanned aerial vehicle does not spray the selenium fertilizer on leaf surfaces; according to the wheat yield level and the fertilizer loss during spraying of the unmanned aerial vehicle, the selenium fertilizer foliage spraying limit of the unmanned aerial vehicle is determined. By limiting the application amount of the selenium fertilizer, the selenium content of wheat grains can be effectively increased under the condition of ensuring grain safety, the aim of strengthening the human body is achieved, and the influence of insufficient selenium content on the human body is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural fertilization, and in particular to a method for limiting the amount of selenium fertilizer sprayed on wheat leaves by unmanned aerial vehicles based on yield levels. Background Art

[0002] Selenium is an essential trace nutrient for the human body and an important component of antioxidant enzymes. Selenium plays a significant role in preventing cardiovascular diseases and diabetes, improving human immunity, and enhancing anti-cancer ability. The human body cannot synthesize selenium by itself and mainly ingests selenium from food. Adults need to consume 55μg of selenium every day. Studies have shown that there are currently about 500 million to 1 billion people in the world who are deficient in selenium. The selenium content in the soil in northern provinces of my country is generally low.

[0003] The main way to solve selenium deficiency in the human body is to increase dietary selenium intake. According to the dietary nutrition recommendations of Chinese and world residents, the selenium content of wheat grains that meet the selenium nutrition needs of the human body should reach the standard of about 300μg / kg. The application of selenium fertilizer is the fastest and most effective agronomic measure to improve the selenium nutrition of crops. Foliar spraying of selenium fertilizer can reduce the decline in the proportion of effective selenium caused by soil adsorption and chemical processes or microbial transformation, thereby increasing the absorption and utilization of exogenous selenium by plants. Wheat has a strong ability to absorb selenium, and up to 50% of the selenium absorbed by wheat is enriched in the grains.

[0004] The selenium supply capacity of soil is divided according to the content of effective selenium in the soil. Before wheat sowing, the soil at a depth of 0 to 20 cm in the wheat field is collected to determine its effective selenium content. Soil with an effective selenium content of <0.1 mg / kg is defined as selenium-deficient soil, 0.1 to 0.2 mg / kg is defined as low-selenium soil, 0.2 to 0.3 mg / kg is defined as medium-selenium soil, and effective selenium >0.3 mg / kg is defined as selenium-rich soil;

[0005] At present, the research on soil, crops and selenium mainly focuses on the effectiveness of selenium in soil, symptoms of crop selenium deficiency, absorption and accumulation of selenium by crops, and preparation methods of selenium fertilizer. Although there are methods for applying selenium fertilizer, and drones can be used to apply selenium fertilizer in the existing technology, excessive application of selenium fertilizer will cause harm to human health. If there is no limit on the amount of selenium applied, it is easy to cause excessive or insufficient application of selenium fertilizer to have adverse effects on human health. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention provides a method for limiting the foliar spraying of selenium fertilizer by drones on wheat based on yield levels, which is used to solve the problem that in the prior art, selenium fertilizer application by drones is not limited in amount, which may easily cause excessive or insufficient selenium fertilizer and have adverse effects on human health.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for limiting the amount of selenium fertilizer sprayed on wheat leaves by drone based on yield level includes the following steps:

[0009] Obtain data on wheat grain selenium content and soil effective selenium content; compare data on wheat grain selenium content and soil effective selenium content;

[0010] When the selenium content of wheat grains and the effective selenium content in the soil are both lower than the preset threshold, the drone will spray selenium fertilizer on the leaves; otherwise, the drone will not spray selenium fertilizer on the leaves;

[0011] The limit of selenium fertilizer sprayed on leaves by drones was determined based on wheat yield levels and fertilizer losses during drone spraying.

[0012] Preferably, the selenium fertilizer is sodium selenite or various organic or inorganic fertilizers containing selenium.

[0013] Preferably, the selenium fertilizer dosage formula is:

[0014] Se app =a×100 / Se con

[0015] Among them, Se app is the amount of selenium fertilizer applied, in g / hm 2 ; a is the amount of pure selenium in the selenium fertilizer sprayed on the leaves by the drone, in g / hm 2 ; Se con It is the selenium content of selenium fertilizer, in %.

[0016] Preferably, when the wheat grain yield level is below 3750kg / hm 2 When spraying selenium fertilizer on leaves, the range is 28~32g / hm 2 ;

[0017] When the wheat grain yield level ranges from 3750 to 5250 kg / hm 2 When spraying selenium fertilizer on leaves, the range is 32~38g / hm 2 ;

[0018] When the wheat grain yield level is higher than 5250kg / hm 2 When spraying selenium fertilizer on leaves, the range is 38~44g / hm 2 .

[0019] Preferably, when the selenium content of wheat grains is lower than 0.3 mg / kg; and the effective selenium content in the soil is lower than 0.3 mg / kg, the drone sprays selenium fertilizer on the leaves; when the selenium content of wheat grains is higher than 0.3 mg / kg or the effective selenium content in the soil is higher than 0.3 mg / kg, the drone does not spray selenium fertilizer on the leaves.

[0020] Preferably, when the UAV sprays selenium fertilizer, the height from the wheat leaf surface ranges from 1.5 to 2.2 meters.

[0021] Preferably, when the drone sprays selenium fertilizer, the flight speed of the drone is in the range of 4 to 7 m / s.

[0022] Preferably, in the preparation of the fertilizer solution of selenium fertilizer, the amount of water used is in the range of 10 to 15 L per hectare, the selenium fertilizer and water are mixed into an aqueous solution according to a certain proportion, and 1 mL of Tween 20 additive is added to every 10 L of solution and mixed evenly.

[0023] Preferably, selenium fertilizer is sprayed on wheat leaves by drone during the jointing-booting stage or within one week after flowering. If it rains within 2 to 3 days after spraying, spraying is performed again.

[0024] Compared with the prior art, the present invention has the following beneficial technical effects:

[0025] The present invention provides a method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level. The method limits the amount of selenium fertilizer sprayed on the leaves of wheat by drone by obtaining data on the selenium content of wheat grains and the effective selenium content of soil, and combines the wheat yield level and the fertilizer loss during drone spraying. The method cooperates with the drone spraying method, and limits the amount of selenium fertilizer applied. After the wheat crop absorbs it, the selenium enters the wheat body through the leaves and is transferred to the grains. The selenium content of wheat grains can be effectively increased while ensuring food security, thereby achieving the goal of strengthening the human body and avoiding the impact on the human body due to insufficient selenium content.

[0026] Instruction Manual

[0027] Figure 1 The present invention is a flow chart of a method for limiting the amount of selenium fertilizer sprayed on wheat leaves by a drone based on yield level. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0029] like Figure 1 As shown, a method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level of the present invention includes the following process:

[0030] Obtain data on wheat selenium content and soil effective selenium content; compare data on wheat selenium content and soil effective selenium content.

[0031] When the selenium content in wheat grains and the effective selenium content in the soil are both lower than the preset threshold, the drone will spray selenium fertilizer on the leaves; otherwise, the drone will not spray selenium fertilizer on the leaves.

[0032] The limit of selenium fertilizer sprayed on leaves by drones was determined based on wheat yield levels and fertilizer losses during drone spraying.

[0033] Specifically, 1) conditions for foliar spraying of selenium fertilizer are limited.

[0034] When the selenium content of wheat grains is lower than 0.3 mg / kg at harvest and when the effective selenium content in the soil is lower than 0.3 mg / kg, foliar spraying of selenium fertilizer is carried out. If the selenium content of wheat grains is higher than 0.3 mg / kg or when the effective selenium content in the soil is higher than 0.3 mg / kg, foliar spraying of selenium fertilizer is not carried out.

[0035] Specifically, 2) based on the wheat yield level and taking into account the fertilizer loss during drone spraying, the limit of selenium fertilizer sprayed on leaves by drone was determined (a).

[0036] Specifically (see Table 1), when the wheat grain yield is less than 3750 kg / hm 2 The recommended amount of selenium fertilizer for foliar spraying is 28-32 g / hm2. 2 ; When wheat grain yield is between 3750~5250kg / hm 2 The recommended amount of selenium fertilizer for foliar spraying is 32-38 g / hm2. 2 ; When wheat grain yield is higher than 5250kg / hm 2 The recommended amount of selenium fertilizer for foliar spraying is 38-44 g / hm2. 2 .

[0037] Fertilizer loss occurs when a drone is spraying. Some selenium fertilizer will always be sprayed onto the soil or evaporated without getting on the leaves. Therefore, it is necessary to consider the fertilizer loss during drone spraying and determine the limit of selenium fertilizer that can be sprayed on leaves by drones.

[0038] Table 1 Limits of selenium fertilizer spraying by drones based on wheat yield levels

[0039]

[0040] 3) Selenium fertilizer dosage (calculated based on pure selenium)

[0041] Se app =a×100 / Se con

[0042] Se app ——Selenium fertilizer application rate, in g / hm2 2 ;

[0043] a——The amount of pure selenium in the selenium fertilizer sprayed on the leaves by drone, in g / hm 2 ;

[0044] Se con ——Selenium content in selenium fertilizer, in %.

[0045] Specifically, the types of selenium fertilizers include: sodium selenite (Na2SeO3), and various organic and inorganic commercial fertilizers containing selenium.

[0046] Specifically, the fertilizer solution is prepared as follows: the amount of water used is 10 to 15 L per hectare, the calculated amount of fertilizer is mixed with water in proportion to form an aqueous solution, and 1 mL of Tween 20 additive is added to every 10 L of solution and mixed.

[0047] Specifically, the fertilizer solution configured above is sprayed using the XAG 2020 agricultural drone. The fertilizer solution is applied at a dosage of 10 to 15 L per hectare, at a height of 1.5 to 2.2 meters from the leaf surface, and at a flight speed of 4 to 7 m / s.

[0048] Specifically, spray selenium fertilizer on the leaves. Spray selenium fertilizer on wheat leaves in the jointing-booting stage or within one week after flowering on a windless cloudy or sunny evening. If it rains within 2 days after spraying, spray again.

[0049] Specifically, foliar spraying of selenium fertilizer can be applied every year.

[0050] Example 1

[0051] This example takes Yujiagong Village in Yongshou County, Shaanxi Province, a rain-fed winter wheat production area, as an example. The soil has an effective selenium content of 0.02 mg / kg, a pH of 8.5, and a local wheat yield of 7200 kg / hm2. 2 When using drone fertilization, 38-44g of selenium fertilizer should be sprayed, and the actual amount of selenium applied (calculated based on pure selenium) is 38g / hm2. 2 .

[0052] 1) Fertilizer calculation

[0053] Since sodium selenite is used as fertilizer, the content of pure selenium in the fertilizer is:

[0054]

[0055] Se con =78.96×100% / 172.94=45.66

[0056] a=38g / hm 2

[0057] Substituting the above values ​​into the formula, Se app =a×100 / Se con

[0058] The amount of sodium selenite fertilizer should be Se app =38×100 / 45.66=83g / hm 2

[0059] 2) Preparation of fertilizer solution: The amount of water used is 12 L per hectare. Mix 83 g of sodium selenite with 12 L of water to make an aqueous solution. At the same time, add 1.2 mL of Tween 20 as an auxiliary agent and mix well.

[0060] 3) The fertilizer solution prepared above was sprayed using a 2020 model agricultural drone from XAG. The fertilizer solution was applied at a dosage of 12L per hectare, at a height of 1.8 meters from the leaf surface, and at a flight speed of 5m / s.

[0061] 4) Spray selenium fertilizer on the leaves during the jointing-booting period or within one week after flowering, on a windless cloudy or sunny evening. If it rains within 2 days after spraying, spray again.

[0062] 5) Implementation effect:

[0063] Table 2 Effects of leaf spraying of selenium fertilizer on wheat yield and selenium content in various organs

[0064]

[0065] Example 2

[0066] This example takes Fengxiang County, a winter wheat production area in Guanzhong, Shaanxi Province, as an example. The soil effective selenium content is 0.021 mg / kg, the pH is 8.2, and the local average wheat yield is 8800 kg / hm2. 2 When using drone fertilization, 38-44g of selenium fertilizer should be sprayed, and the actual amount of selenium applied (calculated based on pure selenium) is 40g / hm 2 .

[0067] 1) Fertilizer calculation Since sodium selenite is used as fertilizer, the content of pure selenium in the fertilizer is:

[0068]

[0069] Se con =78.96×100% / 172.94=45.66

[0070] a=40g / hm 2

[0071] Substituting the above values ​​into the formula, Se app =a×100 / Se con

[0072] Se app =40×100 / 45.66=87.6g / hm 2

[0073] 2) Preparation of fertilizer solution: The amount of water used is 12 L per hectare. Mix 87.6 g of sodium selenite with 12 L of water to make an aqueous solution. At the same time, add 1.2 ml of Tween 20 as an auxiliary agent and mix well.

[0074] 3) The fertilizer solution prepared above was sprayed using a 2020 XAG agricultural drone. The fertilizer solution was applied at a rate of 12L per hectare, at a height of 1.6 meters from the leaf surface, and at a flight speed of 7m / s.

[0075] 4) Spray selenium fertilizer on the leaves. Spray selenium fertilizer on the wheat leaves in the jointing-booting stage or within one week after flowering on a windless cloudy or sunny evening. If it rains within 2 days after spraying, spray again.

[0076] 5) Implementation effect

[0077] Table 3 Effects of leaf spraying of selenium fertilizer on wheat yield and selenium content in various organs

[0078]

Claims

1. A method for limiting the amount of selenium fertilizer sprayed on wheat leaves by drones based on yield level, characterized in that: Including the following process, Obtain data on wheat selenium content and soil effective selenium content; compare data on wheat grain selenium content and soil effective selenium content; When the selenium content of wheat grains and the effective selenium content in the soil are both lower than the preset threshold, the drone will spray selenium fertilizer on the leaves; otherwise, the drone will not spray selenium fertilizer on the leaves; The limit of selenium fertilizer sprayed on leaves by drones was determined based on wheat yield levels and fertilizer losses during drone spraying.

2. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: The selenium fertilizer is sodium selenite or various organic or inorganic fertilizers containing selenium.

3. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: The dosage formula of selenium fertilizer is: Yes app =a×100 / Se con Among them, Se app is the amount of selenium fertilizer applied, in g / hm 2 ; a is the amount of pure selenium in the selenium fertilizer sprayed on the leaves by the drone, in g / hm 2 ; Se con It is the selenium content of selenium fertilizer, in %.

4. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: When the wheat grain yield level is lower than 3750kg / hm 2 When spraying selenium fertilizer on leaves, the range is 28~32g / hm 2 ; When the wheat grain yield level ranges from 3750 to 5250 kg / hm 2 When spraying selenium fertilizer on leaves, the range is 32~38g / hm 2 ; When the wheat grain yield level is higher than 5250kg / hm 2 When spraying selenium fertilizer on leaves, the range is 38~44g / hm 2 .

5. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: When the selenium content in wheat grains is lower than 0.3 mg / kg, and the effective selenium content in the soil is lower than 0.3 mg / kg, the drone will spray selenium fertilizer on the leaves; when the selenium content in wheat grains is higher than 0.3 mg / kg or the effective selenium content in the soil is higher than 0.3 mg / kg, the drone will not spray selenium fertilizer on the leaves.

6. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: When the drone sprays selenium fertilizer, the height from the wheat leaves ranges from 1.5 to 2.2 meters.

7. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: When the UAV sprays selenium fertilizer, the flight speed of the UAV ranges from 4 to 7 m / s.

8. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1 is characterized in that: The fertilizer solution of selenium fertilizer is prepared with a water dosage range of 10 to 15 L per hectare. Selenium fertilizer and water are mixed into an aqueous solution according to a certain proportion, and 1 mL of Tween 20 additive is added to every 10 L of solution and mixed evenly.

9. The method for limiting the amount of selenium fertilizer sprayed on the leaves of wheat by drone based on yield level according to claim 1, characterized in that: During the jointing-booting stage or within one week after flowering, selenium fertilizer is sprayed on the wheat leaves by drone. If it rains within 2 to 3 days after spraying, spray again.

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