阅读说明：本技术 一种缓解夏玉米高温热害的方法 (Method for relieving high-temperature heat damage of summer corn ) 是由 朱英华 章鑫 王成雨 马庆 李晓玉 程备久 董召荣 周可金 余燕 陈翔 程玉庆 于 2019-12-19 设计创作，主要内容包括：本发明公开了一种缓解夏玉米高温热害的方法,属于夏玉米种植领域,所述方法包括以下步骤：将顺丁烯二酸联胺溶解于二乙醇胺中,然后兑水将上述溶液调配为所需浓度的顺丁烯二酸联胺溶液,在夏玉米播种后的第45d至抽雄前,选择无风晴朗的上午或傍晚,将顺丁烯二酸联胺溶液采用农用喷雾机均匀喷施到玉米叶片表面。本发明所述顺丁烯二酸联胺溶液可用于缓解夏玉米高温热害。(The invention discloses a method for relieving high-temperature heat damage of summer corns, which belongs to the field of summer corn planting and comprises the following steps: dissolving maleic acid diamine in diethanolamine, adding water to prepare a maleic acid diamine solution with a required concentration, and uniformly spraying the maleic acid diamine solution on the surfaces of the corn leaves in the 45 th day after sowing summer corns and before castration in the morning or evening without wind. The maleic acid hydrazine solution can be used for relieving the high-temperature heat damage of summer corn.)

1. A method for relieving high-temperature heat damage of summer corn is characterized by comprising the following steps: dissolving maleic acid diamine in diethanolamine, adding water to prepare a maleic acid diamine solution with a required concentration, and uniformly spraying the maleic acid diamine solution on the surfaces of the corn leaves in the 45 th day after sowing summer corns and before castration in the morning or evening without wind.

2. The method of claim 1, wherein the method comprises: the concentration of the prepared maleic acid diamine solution is 0.9-1.1mmol/L, and the spraying amount of the maleic acid diamine solution is 530-550L/ha.

3. The method of claim 1, wherein the method comprises: 112g of maleic acid diamine is dissolved in 200ml of diethanolamine, then 1000L of water is added, and the solution is prepared into a maleic acid diamine solution with the concentration of 1 mmol/L.

4. The method of claim 3, wherein the method comprises: the spraying amount of the maleic acid diamine solution is 540L per hectare.

5. The method of claim 1, wherein the method comprises: the morning of the windless sunny day is before 8 o 'clock, and the evening is after 17 o' clock.

Technical Field

The invention relates to the field of summer corn planting, in particular to a method for relieving high-temperature heat damage of summer corn.

Background

Along with global warming, extreme high temperature events frequently occur, and the global food safety is seriously threatened. Corn is the first major food crop in the world, and the production of the corn plays a very important role in guaranteeing global food supply, particularly summer corn lives in hot summer in most of the whole growth period, and the whole growth season is greatly influenced by high temperature. For summer corn, temperatures above 35 ℃ are considered to meet the high temperature damage criteria. After the corn is damaged by high temperature, the corn is short and small in plant, the leaves turn yellow and become thin, physiological metabolism is disordered, the vitality of pollen and filaments is reduced, the corn ears are small and can not normally fruit, and finally the yield of the corn is reduced. Studies have shown that corn is most sensitive to high temperatures from the large flare stage to the flowering stage, where high temperatures are experienced and corn damage and reduced yield are the most severe. Therefore, in addition to selecting high temperature resistant varieties, it is very important to develop efficient low-cost chemical preparations to reduce the influence of high temperature damage on the corn at this stage.

Disclosure of Invention

The invention aims to provide a method for relieving high-temperature heat damage of summer corns, which can relieve the high-temperature heat damage of the summer corns.

In order to achieve the purpose, the invention provides the following technical scheme:

a method for relieving high-temperature heat damage of summer corn comprises the following steps: dissolving maleic acid diamine in diethanolamine, adding water to prepare a maleic acid diamine solution with a required concentration, and uniformly spraying the maleic acid diamine solution on the surfaces of the corn leaves in the 45 th day after sowing summer corns and before castration in the morning or evening without wind.

Preferably, the concentration of the prepared maleic acid diamine solution is 0.9-1.1mmol/L, and the spraying amount of the maleic acid diamine solution is 530-550L/ha.

Preferably, 112g of the maleic acid diamine is dissolved in 200ml of diethanolamine, and then 1000L of water is added to prepare the solution into a maleic acid diamine solution with the concentration of 1 mmol/L.

Preferably, the spraying amount of the maleic acid diamine solution is 540L per hectare.

Preferably, the sunny morning is 8 am and the evening is 17 pm.

Compared with the prior art, the invention has the beneficial effects that:

the yield loss caused by the high temperature of the summer corn can be reduced by spraying 0.9-1.1mmol/L maleic acid diamine solution. The specific principle is as follows: by spraying the maleic acid hydrazine solution, on one hand, the relative conductivity of the leaves can be reduced, the stability of cell membranes can be maintained, the chlorophyll content of the leaves can be improved, and the photosynthetic capacity can be enhanced, so that the supply capacity of a plant source can be improved; on the other hand, the male-female interval period of the summer corn can be shortened, the pollen activity and the filament activity of the summer corn are improved, and the number of grains per spike is increased, so that the accommodation capacity of a plant 'bank' is enlarged.

Secondly, by spraying 0.9-1.1mmol/L maleic acid diamine solution, the number of grains per ear of the summer corn is improved by 28.2%, the thousand kernel weight is improved by 10.5%, and the yield is improved by 39.0%.

Drawings

FIG. 1 shows the effect of maleic acid hydrazine spraying on chlorophyll at the scion of the nephrite leaves under high temperature treatment;

FIG. 2 is a graph showing the effect of maleic acid hydrazine spraying on the photosynthetic rate of the leaves at the ear position of summer corn under high temperature treatment;

FIG. 3 is a graph showing the effect of maleic acid diamine spraying on the relative conductivity of the leaves at the ear position of summer corn under high temperature treatment;

FIG. 4 is a graph showing the effect of maleic acid diamine spraying on the male-female interval of summer corn under high temperature treatment;

FIG. 5 is a graph showing the effect of maleic acid hydrazine spraying on the pollen viability of summer maize under high temperature treatment;

FIG. 6 is a graph showing the effect of maleic acid hydrazine spraying on the activity of summer corn filaments treated at high temperature.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

A method for relieving high-temperature heat damage of summer corn comprises the following steps: dissolving maleic acid diamine in diethanolamine, adding water to prepare a maleic acid diamine solution with a required concentration, and uniformly spraying the maleic acid diamine solution on the surfaces of the corn leaves in the 45 th day after sowing summer corns and before castration in the morning or evening without wind. The morning of the windless sunny day is before 8 o 'clock, and the evening is after 17 o' clock. The concentration of the prepared maleic acid diamine solution is 0.9-1.1mmol/L, and the spraying amount of the maleic acid diamine solution is 530-550L/ha. Preferably, 112g of maleic acid diamine is dissolved in 200ml of diethanolamine, then 1000L of water is added, the solution is prepared into a 1mmol/L maleic acid diamine solution, and the spraying amount of the 1mmol/L maleic acid diamine solution is 540L per hectare.

The following is an experimental example of using maleic acid diamine solution as a chemical agent to relieve high-temperature heat damage of summer corn.

1.1 materials and methods

The test is carried out in Zhangzhuancun of Yingquan region Wangfuying community in Fuyang city, Anhui province in 2017, and the corn variety used in the test is a heat-sensitive variety Shanghai 605. The test set up 2 treatments at high temperature: one treatment is spraying 1mmol/L maleic acid diamine treatment (T); one treatment was control treatment (CK) and an equal amount of clear water was sprayed.

The high-temperature treatment method comprises the steps of erecting a polyethylene plastic film greenhouse with the transmittance of 95 percent to heat, and keeping the temperature in the polyethylene plastic film greenhouse not lower than 35 ℃ when the external environment temperature (the temperature of the atmosphere outside the greenhouse) is lower than 35 ℃; when the environmental temperature (the temperature of the atmosphere outside the greenhouse) is higher than 35 ℃, keeping the temperature in the polyethylene plastic film greenhouse higher than the temperature of the outside environment (the temperature of the atmosphere outside the greenhouse) by 3 ℃; when the temperature in the polyethylene plastic film greenhouse is higher than 38 ℃, the film is uncovered, the temperature is reduced to be lower than 38 ℃, and then the film is covered again, and the steps are repeated, so that the temperature in the greenhouse is kept within a controllable range. The specific specifications of the polyethylene plastic film greenhouse are as follows: the length is 20m, the width is 10m, the height is 5m, and the framework structure is a galvanized steel pipe.

The high-temperature treatment period starts at 45d after summer corn is sowed and ends at 7d after flowering and powder scattering. And uniformly spraying the maleic acid hydrazine solution on the surfaces of the corn leaves by adopting an agricultural sprayer in the windless morning or evening 45 days after the corn is sowed in summer until the male part is removed.

The spraying concentration of the maleic acid diamine is 1mmol/L, when the solution is sprayed, 112g of the maleic acid diamine is firstly dissolved in 200ml of diethanolamine, then water is added to 1000L, the solution is prepared into the maleic acid diamine solution with the concentration of 1mmol/L, and the spraying amount per unit area is 540L of the maleic acid diamine solution with the concentration of 1mmol/L per hectare.

The planting density of summer corn in the test field is 60000 plants/hm²Wherein the row spacing is 60cm, and the plant spacing is 27.7 cm. The application amount of the nitrogen fertilizer (pure nitrogen) is 300kg/hm²Wherein 1/2 is used as a base fertilizer, 1/2 is used as an additional fertilizer; potassium fertilizer (K)₂O) application rate of 105kg/hm²Phosphate fertilizer (P)₂O₅) The application rate is 120kg/hm²The phosphate fertilizer and the potash fertilizer are both in the form of base fertilizer before sowingApplying the fertilizer into soil. Other management measures are in accordance with the planting habits of local farmers.

1.2 measurement items and indices

1.2.1 yield

Selecting 3 points for each treatment, measuring the total length of 50 plants at each point, calculating the average plant spacing, measuring the row spacing, and calculating the spike number per mu by using the plant row spacing. Yield is ear number per mu and ear weight per thousand grains.

1.2.2 chlorophyll content

The determination period is a powder scattering period, and the chlorophyll content of the ear position leaf is determined by 95% alcohol extraction and spectrophotometry. The chlorophyll content change width (%) - (T-CK)/CK × 100.

1.2.3 photosynthetic Rate

The determination period is a powder scattering period, and the determination of the net photosynthetic rate of the leaves at the panicle position is determined by a CIRAS-HPEA plant photosynthetic system determinator. The variation range of the net photosynthetic rate of panicle leaf is (T-CK)/CK 100.

1.2.4 relative conductivity

The determination period is a powder scattering period, the relative conductivity of the ear position leaves adopts a soaking method, 3 parts of fresh samples are taken for each treatment, 0.1g of fresh samples are quickly weighed, the fresh samples are respectively placed in a graduated test tube of 10ml of deionized water to be soaked for 12h at room temperature, a conductivity meter is used for determining the conductivity (R1) of the leaching solution, then the fresh samples are heated for 30min by boiling water, the mixture is cooled to room temperature and then shaken up, the conductivity (R2) of the leaching solution is determined again, and the relative conductivity is R1/R2. The relative conductivity change width is (T-CK)/CK 100.

1.2.5 Male and female Interval stages

The interval period between male and female is the interval between the powder scattering period and the spinning period. The variation range of the interval period between male and female is (T-CK)/CK 100.

1.2.6 pollen viability

The measuring period is a pollen scattering period, and the pollen activity adopts a triphenyltetrazolium chloride (TTC) method. The pollen vitality change amplitude is (T-CK)/CK 100.

1.2.7 vigor of the filaments

Bagging the female ears of the corn plants subjected to high-temperature treatment before pollen scattering by using a parchment bag, collecting sufficient pollen from the plants which are not subjected to high-temperature treatment for artificial pollination, continuously pollinating until the pollen scattering of the plants which are not subjected to high-temperature treatment is finished, and taking the ratio (%) of the number of the fructified corn ears to the number of the non-high-temperature-treated corn ears as a filament vitality value.

Amplitude (T-CK)/CK 100.

2 analysis of results

2.1 the Effect of maleic acid Linked amine spraying on the yield of summer maize processed at high temperature and its constituent factors

As can be seen from Table 1, the effect of maleic acid diamine spraying after high-temperature treatment on the ear number per unit area of the Shanghai 605 variety of summer maize is not significant, because the high-temperature treatment occurs in the large flare stage of the maize, and the ear number per unit area of the maize is already determined; however, compared with the control treatment (CK), the maleic acid diamine (T) sprayed after the high-temperature treatment obviously improves the number of grains per ear and the thousand kernel weight, and further obviously improves the yield of summer corn kernels, wherein the improvement range of the number of grains per ear is 28.2%, the improvement range of the thousand kernel weight is 10.5%, the improvement range of the yield is 39.0%, the improvement range of the number of grains per ear (28.2%) is larger than the improvement range of the thousand kernel weight (10.5%), and the improvement of the yield of the maleic acid diamine sprayed after the high-temperature treatment is mainly completed by improving the number of grains per ear compared with the control treatment (CK).

TABLE 1 Effect of maleic acid diamine spraying on the yield of summer maize at high temperature and its constituents

Treatment of	Ear number per unit area (plant/hm 2)	Grain number per ear (grain/plant)	Thousand Kernel weight (g)	Yield (kg/hm2)
					CK	61230.5a	283.1b	305.6b	4502.6b
T	60075.4a	362.9a	337.8a	6259.8a

2.2 Effect of maleic acid Linked amine spraying on chlorophyll of summer maize ear at high temperature

Chlorophyll is a key substance for plant photosynthesis and can convert light energy into stable chemical energy, so that the level of the chlorophyll is an important physiological index for reflecting whether plant metabolism is normal or not, and the level of the chlorophyll is closely related to the stress resistance of plants.

As can be seen from fig. 1, spraying maleic acid diamine (T) after high temperature treatment significantly increases the spike chlorophyll SPAD value compared to the control treatment (CK), the spike chlorophyll SPAD value of the control treatment (CK) is 46.3, the spike chlorophyll SPAD value of the maleic acid diamine (T) after spraying is 51.3, and the increase is 10.8%, and thus, spraying maleic acid diamine (T) can improve and increase the chlorophyll content of summer maize leaves under high temperature conditions.

2.3 Effect of maleic acid Linked amine spraying on the net photosynthetic Rate of leaf at ear position of summer corn under high temperature treatment

Under the action of chlorophyll, plants can synthesize H through photosynthesis₂O and CO in air₂The carbohydrate is converted into carbohydrate, and the carbohydrate constitutes the main part of the dry matter weight of the plant body, so that the high and low of photosynthesis directly determines the high and low yield, and one of the reasons for the yield reduction caused by high temperature is the dry matter weight of the plant bodyThus, whether the chemical regulator can improve the net photosynthetic capacity of the green organs of the plants under the stress condition of the plants can be regarded as the basis for evaluating whether the reagent is effective.

As can be seen from FIG. 2, the spraying of maleic acid diamine (T) after the high-temperature treatment significantly increases the net photosynthetic rate of leaves at the ear position compared with the control treatment (CK), and the net photosynthetic rate of leaves at the ear position of the control treatment (CK) is 35.7. mu. mol CO₂m^-2S^-1The net photosynthetic rate of the leaves at the ear position sprayed with maleic acid diamine (T) is 40.1 mu mol of CO₂m^-2S^-1The improvement range is 12.3%, therefore, the spraying of maleic acid diamine (T) can improve and provide the net photosynthetic capacity of summer corn leaves under the high-temperature condition, and dry matter accumulation and storage capacity of summer corn under the high-temperature condition are enhanced.

2.4 Effect of maleic acid Linked amine spraying on the relative conductivity of the ear leaves of summer corn under high temperature treatment

The plant cell membrane plays a role in regulating and controlling the exchange of substances inside and outside the cell, and the selective permeability of the plant cell membrane is one of the most important functions of the plant cell membrane. When plants are damaged by stress, cell membranes are damaged to different degrees, membrane permeability is increased, selective permeability is lost, and partial electrolytes in cells are infiltrated. Therefore, the measurement of plasma membrane permeability can be used as a physiological index of adversity damage and widely applied to the physiological research of plant resistance.

As can be seen from fig. 3, after the high-temperature treatment, the maleic acid diamine (T) spray application significantly reduced the relative conductivity of the leaves at the ear position compared to the control treatment (CK), the relative conductivity of the leaves at the ear position of the control treatment (CK) was 0.84, the relative conductivity of the leaves at the ear position sprayed with maleic acid diamine (T) was 0.66, and the reduction was 21.4%. Therefore, the spraying of the maleic acid hydrazine reduces the relative conductivity of the ear position and the leaf of the summer corn, enhances the stability of cell membranes, and plays an important role in maintaining the relatively normal physiological activity of the summer corn plants.

2.5 Effect of maleic acid Linked amine spraying on the Male and female intervals of summer corn under high temperature treatment

The interval period of male and female is the phenomenon that the flowering periods of the female flowers and the male flowers of the isogamic cross pollination crops such as corn and the like are different. Normally, the interval between male and female of corn is 0 or very short, but when the corn is stressed by high temperature in the flowering period, the flowering interval between the female ear and the male ear is increased. The consequence of the excessive male and female spacing periods is that when the female and male ears bloom, the normal flowering and pollination of corn cannot be normally carried out due to the reduction of the pollen activity (male flower) or the filament activity (female flower) of corn in the floral organs of the opposite sex, resulting in the reduction of the corn kernel yield.

As can be seen from fig. 4, the spraying of maleic acid diamine (T) after the high-temperature treatment significantly reduced the male-female interval of the summer corn compared to the control treatment (CK), which was 2.9d, and the spraying of maleic acid diamine (T) was 2.1d, which was a reduction of 27.6%. Therefore, spraying maleic acid diamine reduces the male-female interval of summer corn, and increases the probability of completing normal fertilization by pollen and filaments.

2.6 Effect of maleic acid Linked amine spraying on pollen Activity of summer maize under high temperature treatment

Pollen activity is the ability of pollen to maintain the fertilization time, the corn emasculation flowering period is most easily damaged by high temperature, the high temperature influences the elongation of a pollen tube and normal pollen dispersion, the pollen activity and the germination ability are reduced, pollen abortion or pollen silks cannot pollinate to form empty grains, the maturing rate is greatly reduced, and serious yield reduction is caused. Treatment of corn pollen at 35 ℃ for 6h will lose all pollen viability and treatment at 40 ℃ for 4h will cause pollen viability loss.

As can be seen from fig. 5, the summer maize pollen activity after the high-temperature treatment is significantly improved by spraying the maleic acid diamine (T) compared with the control treatment (CK), the summer maize pollen activity after the control treatment (CK) is 67.9%, the summer maize pollen activity after the maleic acid diamine (T) is sprayed is 85.4%, and the improvement amplitude is 25.8%.

2.7 Effect of maleic acid Linked amine spraying on the Activity of summer maize filaments under high temperature treatment

The high temperature inhibits the elongation of the filaments, slows down the spinning rate of the filaments in the maize tasseling period, and simultaneously, the high temperature obviously slows down the growth of the filaments, so that the length of the filaments is obviously reduced. The water potential of the corn filament is easily reduced due to high temperature, and even if pollen germinates, the surface of the filament lacks enough moisture to cause incapability of fertilization, so that the seed setting rate is greatly reduced. The high temperature causes no mucus on the surface of the corn filament, so that the pollen adhesion is reduced, thereby greatly reducing the pollination probability of the corn filament and causing the reduction of yield. High temperatures also result in shortened life and reduced viability of the corn filaments.

As can be seen from fig. 6, after the high-temperature treatment, the maleic acid diamine (T) spraying significantly improves the activity of the filaments of the summer corn compared with the control treatment (CK), the activity of the filaments of the summer corn after the control treatment (CK) is 64.9%, the activity of the filaments of the summer corn after the maleic acid diamine (T) spraying is 82.7, and the improvement range is 27.4%.

3. Conclusion

According to the research, the yield loss of summer corn caused by high temperature can be reduced under the high temperature condition by spraying the solution of 1mmol/L maleic acid diamine. The principle that the solution of maleic acid diamine relieves the high-temperature heat damage of summer corn is as follows: on one hand, the spraying of the solution can reduce the relative conductivity of leaves, maintain the stability of cell membranes, improve the chlorophyll content and enhance the photosynthetic capacity, thereby improving the supply capacity of plant sources; on the other hand, the spraying of the solution can shorten the male-female interval period of the summer corn, improve the pollen activity and the filament activity of the summer corn, and increase the number of grains per spike, thereby expanding the holding capacity of a plant 'bank'.

The foregoing is merely exemplary and illustrative of the present invention and various modifications, additions and substitutions may be made by those skilled in the art to the specific embodiments described without departing from the scope of the present invention as defined in the accompanying claims.