CN112616838B

CN112616838B - Cotton seed initiator and method for treating cotton seeds by using initiator

Info

Publication number: CN112616838B
Application number: CN202011637051.7A
Authority: CN
Inventors: 张亚林; 魏锋; 刘妤玲; 师勇强; 朱荷琴; 赵丽红; 冯自力; 冯鸿杰; 李胜; 袁媛
Original assignee: Institute of Cotton Research of Chinese Academy of Agricultural Sciences; Guangxi Tianyuan Biochemical Co Ltd
Current assignee: Institute of Cotton Research of Chinese Academy of Agricultural Sciences; Guangxi Tianyuan Biochemical Co Ltd
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2022-03-25
Anticipated expiration: 2040-12-31
Also published as: CN112616838A

Abstract

The invention provides a cotton seed initiator which comprises gibberellin, thiamethoxam and an auxiliary agent. The invention also provides a method for treating cotton seeds by using the initiator, which comprises the steps of soaking the cotton seeds in the initiator, drying the cotton seeds again, and then sowing the cotton seeds or storing the cotton seeds for later use. The method for treating cotton seeds can obviously improve the seed activity, the seedling quality and the target dosage in seedling leaves under the adverse (low-temperature and saline-alkali) condition, and has good effects of improving the germination rate of the seeds in the saline soil adverse environment and preventing and treating diseases of the cotton in the seedling stage.

Description

Cotton seed initiator and method for treating cotton seeds by using initiator

Technical Field

The invention relates to the technical field of seed treatment, in particular to a cotton seed initiator and a method for treating cotton seeds by using the initiator.

Background

Cotton (Gossypium hirsutum L.) is a nationwide important economic crop and is planted in the yellow river basin, the Yangtze river basin and the northwest inland of China. In recent years, the production of Xinjiang cotton is rapidly developed, the Xinjiang cotton accounts for 75.0% of the area of cotton planted nationwide, and certain planting areas are still reserved in the rivers or coastal areas of the yellow river basin and the Yangtze river basin. In cotton production, the strong and full seedlings are the most basic guarantee for high and stable yield of cotton. However, in the three cotton areas, the cotton is stressed by biotic and abiotic adversities after being sown, so that the emergence of the cotton is seriously threatened. The biological stress mainly comprises seedling stage root rot diseases and insect pests such as seedling stage aphids, thrips, cutworms, grubs and the like; abiotic stresses mainly include low temperature and saline-alkali. Particularly, the frost-free period of a cotton area in Xinjiang is short, the soil is seriously salinized, severe weather such as strong wind, cooling, rainfall and the like is very easy to appear in spring, the seedling disease is serious, and the seedling aphid harm is rampant, so that the seedling aphid harm becomes a main limiting factor for developing the production of the Xinjiang cotton.

The method for treating cotton seeds by using the medicament is a common method for preventing and treating plant diseases and insect pests in the seedling stage of cotton. Common seed treatment methods include seed dressing and seed coating treatments. Seed dressing treatment needs to be carried out at present, and operation is not easy for farmers. Therefore, most of the cotton seeds sold at present are coated cotton seeds. However, the cotton seeds treated by the coating have a serious problem in production, namely after the cotton seeds are sowed in spring, if strong rainfall causes water accumulation in soil, after the coating on the surfaces of the seeds is dissolved, liquid medicine with high concentration is formed around the seeds to coat the seeds, so that serious phytotoxicity is caused to the emergence of the seeds, and the seeds are rotted.

Seed priming is an effective way to improve seed vigor, and is a seed treatment technology for controlling slow water absorption and gradual drying of seeds. The basic principle is to control the seeds to slowly absorb water, so that the seeds stay in the second stage of imbibition, and the seeds are subjected to the physiological and biochemical metabolism and repair functions of pre-germination, the repair of cell membranes, organelles and DNA and the activation of enzymes are promoted, so that the seeds are in the metabolic state of germination but the radicles are prevented from extending out. The seed activity of many initiated crops is improved, and the germination can be accelerated under adverse conditions such as low temperature, high temperature, drought, salt or flooding stress and the like, so that the germination rate and the emergence rate are improved, the emergence is uniform, the seedling rate is improved, and the crop yield can be improved.

The effect of seed priming technology on improving seed viability is influenced by a variety of factors, with seed disinfection, priming time and temperature being the most important factors before pretreatment. The existing research mostly adopts water and inorganic salt for initiation treatment, and seeds are directly sown after treatment, so that the production problems of weak growth vigor, uneven seedling emergence and the like easily occur.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The first purpose of the invention is to provide a cotton seed initiator.

The second purpose of the invention is to provide a method for treating cotton seeds by using the initiator, which can enable the cotton seeds to absorb target medicaments by adding medicaments (such as hormone and insecticide) into the initiator to initiate and return to dry, thereby realizing the effects of resisting stress, promoting growth and preventing and treating plant diseases and insect pests.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the invention relates to a cotton seed initiator which comprises a solute and a solvent, wherein the solute is a combination of gibberellin, thiamethoxam and an auxiliary agent.

Preferably, the adjuvant is at least one selected from tributyl phosphate and dibutyl sebacate, and the adjuvant has both lipophilic and hydrophilic properties, and can promote the dispersion of the medicament in the mixed solvent and further promote the absorption of the medicament by the seeds.

Preferably, the solvent is water and/or an organic solvent selected from at least one of ethanol and dimethyl sulfoxide, and the organic solvent is added to dissolve the water-insoluble pharmaceutical agent. Preferably, the solvent is a mixed solvent of water and an organic solvent, and the volume ratio of the water to the organic solvent is 20-50: 1.

preferably, the concentration of the gibberellin in the initiator is 50-400 mg/L, the concentration of the thiamethoxam in the initiator is 0.1-0.8%, and the concentration of the auxiliary agent in the initiator is 0.01-0.05%.

The invention also relates to a method for treating cotton seeds by using the initiator, which comprises the steps of soaking the cotton seeds in the initiator, drying the cotton seeds again, and then sowing the cotton seeds or storing the cotton seeds for later use.

Preferably, the soaking temperature is 25-30 ℃, and the soaking initiation time is 8-16 h.

Preferably, the drying temperature is 35-50 ℃, and the time is 40-60 h.

Preferably, the seed coat of the cotton seed is disinfected before being soaked by adopting an initiator, alcohol with the volume fraction of 75% is used for disinfection, and the disinfection time is 5-20 min, so that pathogenic bacteria carried on the surface of the seed are killed.

In one embodiment of the present invention, the method for treating cotton seeds with the initiator comprises the steps of:

(1) and (3) disinfection: disinfecting the seed coats of the cotton seeds by using alcohol with the volume fraction of 75%, wherein the disinfection time is 5-20 min;

(2) seed soaking: soaking the disinfected cotton seeds in an initiator at the temperature of 25-30 ℃ for 8-16 h, and taking out the seeds after seed soaking for water control treatment;

(3) drying: and (3) placing the cotton seeds after water control in a drying box at 35-50 ℃, and drying for 40-60 h.

The invention has the beneficial effects that:

(1) the existing cotton seed treatment methods comprise seed dressing or seed coating. The two modes of the preparation have large dosage, influence the seedling emergence in low-temperature and high-humidity years, and have certain destructive effect on microorganisms in soil. The initiator provided by the invention is used for treating cotton seeds, has small dosage and simple operation, and can be used for large-batch seed treatment.

(2) The method for treating the seeds can obviously improve the germination rate and the biomass of the cotton seedlings and enhance the stress resistance of the cotton seedlings especially under the conditions of low temperature (18 ℃, 12h of illumination, 4 ℃, 12h of darkness and 60 percent of relative humidity). Because Xinjiang cotton production faces low-temperature cold damage, the seed initiation technology provided by the invention can improve the germination rate of seeds in a low-temperature adverse environment and solve the problem of low-temperature cold damage of cotton.

(3) The method for treating the seeds can obviously improve the content of thiamethoxam in cotton seedling leaves, and has good effect of preventing and controlling seedling aphids. 31.5-50.2% of prevention and control effect on cotton seedling diseases, 82.4-93.1% of aphid prevention and control effect, 41.8-78.2% of thrips prevention and control effect, more than 80 days of pesticide duration and no adverse effect on cotton seedling emergence.

Detailed Description

The following examples are given by the inventors in order that the present invention may be better understood and put into practical effect by those skilled in the art, and are not to be construed as limiting the present invention. The experimental procedures in the following examples are conventional unless otherwise specified. Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

Example 1 Sterilization treatment of seeds before priming

In order to prevent the influence of the mixed bacteria carried on the surface of the seeds on the germination of the seeds and the spread of pathogenic bacteria after the initiation, the invention firstly needs to carry out surface disinfection treatment on the seeds.

1 Disinfection Process

Placing 100g of cotton seeds in a glass ware, adding 200ml of 75% alcohol, sterilizing for 5min, 10min and 20min respectively, taking out, and drying surface liquid with absorbent paper.

2 detection index

And (3) detecting surface bacteria: placing the sterilized cotton seeds and the non-sterilized cotton seeds on PDA culture medium, placing 3 grains per culture medium, treating 5 culture media per treatment, placing at room temperature, and observing the growth condition of mixed bacteria after 3 days.

And (3) detecting the germination rate of the seeds: the seed germination rate is detected according to the national standard, specifically, 800g of soil is weighed in a square germination box, the initiated cotton seeds are uniformly scattered on the surface of the soil, and then 200g of soil is covered. Each 100 seeds treated, 3 replicates. Placing in a light incubator at normal temperature (28 deg.C, 12h light, 12h dark, 60% relative humidity).

The day was recorded as day 0 of sowing, and the temperature and humidity in the germination chamber and the moisture in the germination box were checked every day. Counting the germination number of cotton seedlings and calculating the germination vigor on the 3 rd day of sowing; and counting the germination number of the cotton seedlings on the 10 th day of sowing, and calculating the germination rate. Germination rate (%) (number of germinated seeds ÷ number of test seeds) × 100; germination potential (%) (number of germinated seeds in a predetermined time ÷ number of test seeds) × 100.

3 results of implementation

The seed surface disinfection time is 0min (blank control) and 5min, and a small amount of mixed bacteria grows; the disinfection time is 10min and 20min, and no mixed bacteria grow. Shows that when the cotton seeds are soaked in 75 percent of alcohol for 10min, the sterilizing effect is good,

the germination rates of the seeds are determined by drying the sterilized surfaces of the cotton seeds, and the results show that the germination rates of 4 gradient cotton seeds are respectively 88.3%, 87.6%, 88.7% and 89.1% in 0min, 5min, 10min and 20min, and the germination rate results of all treatment groups have no significant difference.

The cotton seeds are recommended to be soaked in 75% alcohol for 10min for surface disinfection before seed priming, so that the risk of the seed carrying bacteria to influence the priming effect and the pathogenic bacteria transmission is reduced.

Example 2 parameter settings for clear Water initiation and Return to dryness

1 parameter setting

Initiation time: the initiation times were set at 8h, 12h, 16h, 20h and 24h for a total of 5 time gradients.

Drying time: the temperature was set at 40 ℃ for 48 h.

2 test procedure

(1) Grouping: the test set up 5 different priming times and blank controls for 6 treatment groups, each weighing 100g of cotton seeds that had been surface sterilized with alcohol.

(2) And (3) initiation: the seeds were immersed in a defined amount of clear water and placed at room temperature for initiation times of 8h, 12h, 16h, 20h and 24h, 5 time gradients. And taking out the initiated cotton seeds, and then, absorbing the moisture on the surfaces of the seeds by using absorbent paper to obtain the initiated seeds.

(3) Drying: and (3) placing the initiated cotton seeds in a 40 ℃ oven, drying for 48h to constant weight, and returning the water content of the seeds to the water content of the seeds without initiation treatment to obtain the dried cotton seeds (the water content of the seeds at the moment is 11%). Taking out and placing in a cool and dry place for later use.

And (3) determining the germination rate of the cotton seeds after the cotton seeds are introduced back to the dry state according to the national standard, and then determining the germination condition of the cotton seeds every 3 months.

3 results of implementation

Influence of seed soaking time on germination rate and water absorption rate of desiccated seed

The cotton variety is used as a medium cotton institute 49, and is soaked in clear water for 0h, 8h, 12h, 16h, 20h and 24h, and the water absorption rate and the germination rate of the medium cotton variety are measured, and the results are shown in table 1. The water absorption rate is high when the seed soaking time is 12 hours, the germination rate is not influenced, the water absorption rate is gradually increased along with the time, the water absorption capacity is 86.1 percent at the maximum when the seeds are soaked for 12 hours, and the water absorption capacity of the seeds is in a saturated state when the seeds are soaked for 16 hours, 20 hours and 24 hours. The seed soaking time is 8h, 12h, 16h, 20h and 24h, and the germination rates are improved by 0.4%, 1.1%, 0.5%, -0.5% and-2.0% compared with the blank control.

TABLE 1 influence of seed soaking in clear water at different times on Water uptake and germination

Note: the data above are the average of four replicates.

The seeds which are subjected to the drying treatment after being initiated by clear water for 12 hours are stored in a dry and shady place, the germination rates of the seeds are respectively determined to be 85.9 percent and 86.3 percent at 3 months and 6 months, and the germination rates are not obviously different from the germination rates of 85.8 percent and 86.1 percent of the untreated seeds. The cotton seeds treated by the method have no influence on the germination rate when stored for 6 months.

Example 3 determination of germination Rate and seedling growth index of seeds after gibberellin Agents were elicited back to dryness

1 preparation of the initiating solution

Weighing 0.05g of gibberellin, fully stirring in 50ml of absolute ethyl alcohol until the gibberellin is completely dissolved, then adding distilled water, uniformly stirring, and finally fixing the volume to 1000ml to obtain a gibberellin initiation solution with the concentration of 50 mg/L. The above preparation method is adopted to obtain the priming solution with the concentration of 100mg/L, 200mg/L and 400 mg/L. 1000ml of 75% alcohol is prepared and used as seed disinfection. The soil used in the test is moderately saline soil in Xinjiang, and the salt content is 8.0g/kg (medium salt content).

2 initiation parameter settings

As in example 2 above.

3 Cotton seed Return to dryness test

The cotton seed priming-back-drying method was as follows, with three replicates tested:

(1) the sterilization method was the same as in example 1.

(2) The sterilized seeds are put into a priming solution with the gibberellin concentration of 50mg/L, and the using amount of the solution is 200 ml. Initiation was carried out at conventional temperatures for 8h, 12h and 16h, with 3 time gradients.

(3) And taking out the cotton seeds treated by the priming solution, and then, absorbing the moisture on the surfaces of the seeds by using absorbent paper to obtain the primed seeds. And (3) placing the cotton seeds in a 40 ℃ oven, drying for 48h to constant weight to return the water content of the seeds to the water content of the seeds without the initiation liquid treatment, thus obtaining the cotton seeds initiated by 50mg/L initiation liquid (the water content of the seeds is 11%). Taking out and placing in a cool and dry place for later use.

According to the method of the steps (1), (2) and (3), cotton seeds initiated by 0mg/L, 100mg/L, 200mg/L and 400mg/L initiation liquid are obtained respectively.

The cotton seeds initiated by the above-mentioned initiation liquids adopt Xinjiang saline soil to simulate the field environment for standard germination experiment: 800g of soil is weighed in a square germination box, cotton seeds initiated by the initiation solutions are uniformly scattered on the surface of the soil, and then 200g of soil is covered. Each 100 seeds treated, 3 replicates. Placing in light incubator at normal temperature (28 deg.C, 12h light, 12h dark, 60% relative humidity) and low temperature (18 deg.C, 12h light, 4 deg.C, 12h dark, 60% relative humidity). And (4) recording the day as the 0 th day of sowing, checking the temperature and humidity in a germination chamber and the moisture in a germination box every day, calculating the germination rate and the germination vigor, counting the seedling length, the root length, the fresh weight and the dry weight of the cotton seedlings, and calculating the vigor index. Wherein the dry weight of the cotton seedling is the weight of deactivating enzymes of the cotton seedling in a 105 ℃ oven for 30min and then drying the cotton seedling in an 80 ℃ oven for 24h, and the vitality index is the germination percentage multiplied by the dry weight (g) of the seedling.

4 results of the implementation

4.1 determination of the germination percentage after gibberellin elicitation and Return to dryness

Seeds were treated with different concentrations of priming solution and the results are shown in table 2. When the seed soaking time is 12 hours, the highest germination rate is 88.9-92.3%, and the difference is obvious compared with a blank control. When seeds are soaked for 8 hours, the germination rates of 0mg/L, 50mg/L, 100mg/L, 200mg/L and 400mg/L of the treated groups are improved by 1.2%, 2.7%, 3.0%, 3.3% and 1.3% compared with the blank control; when seeds are soaked for 12 hours, the germination rates of 0mg/L, 50mg/L, 100mg/L, 200mg/L and 400mg/L of the treated groups are respectively improved by 0.9%, 4.2%, 8.2%, 7.6% and 6.3% compared with blank control; when the seeds are soaked for 16 hours, the germination rates of the treated groups of 0mg/L, 50mg/L, 100mg/L, 200mg/L and 400mg/L are all improved by 3.9%, 4.5%, 4.1%, 4.6% and 2.6% compared with the blank control.

TABLE 2 comparison of germination percentage results for the same seed soaking time with different concentrations of priming solution

Note: the different lower case letters indicated a significant difference at the 0.05 level between the treatment groups

4.2 optimum seed soaking time (12h) treatment of seeds to determine germination rate and seedling quality

The results of the method are shown in Table 3, and the germination vigor, the germination rate, the vigor index, the seedling length, the root length, the fresh weight and the dry weight of the cotton seeds treated by the initiation liquid with the gibberellin concentration of 50 mg/L-400 mg/L are obviously higher than those of the blank control under the normal temperature condition. Wherein, the best treatment effect is achieved when the concentration of the gibberellin is 100 mg/L. Under the condition of low temperature, after cotton seeds are treated by the initiation liquid with gibberellin concentration of 50-400 mg/L, the germination vigor, the germination rate, the vitality index, the seedling length, the root length, the fresh weight and the dry weight are obviously improved compared with a blank control. Wherein, when the concentration of the gibberellin is 100mg/L, the treatment effect is best, and the low-temperature stress resistance of the cotton is improved.

TABLE 3 comparison of germination rate and seedling quality results of different concentrations of priming solutions for cotton seeds

Note: the different lower case letters indicate a significant difference at the 0.05 level between the treatment groups.

The gibberellin solution is stored at normal temperature and a dry place to induce the cotton seeds to be dried back, when the cotton seeds are stored for 3 months and 6 months, the germination rates are 86.2-89.3% and 86.1-87.8% respectively, and the storage time does not influence the germination rates of the seeds.

Example 4 seed viability assay and young leaf traditional Chinese medicine quantity assay after thiamethoxam dosing back to dryness

Cotton seeds were treated as described in example 2, with thiamethoxam agents used at concentrations of 0.0%, 0.1%, 0.2%, 0.4%, 0.8% and 1.0%, treated for 12h by seed soaking, and then allowed to dry back. And (5) measuring the content of thiamethoxam in the seed coat and the kernel after the seeds are dried back. Meanwhile, the seeds after initiation are placed in an illumination incubator at normal temperature (28 ℃, 12h illumination, 12h darkness and 60% relative humidity) to carry out germination vigor, germination rate, seedling length, root length, fresh weight and dry weight and thiamethoxam content detection in seedling leaves, which are detailed in table 4. The result shows that when the concentration of the liquid medicine is 0.1-0.8%, the seed germination vigor and the germination rate are not affected, and the seed germination vigor and the germination rate are not significantly different from those of a blank control. When the concentration of the thiamethoxam solution reaches 1.0%, the germination vigor and the germination rate of the seeds are obviously affected, and are reduced by 19.0% and 71.5% compared with a control. When the concentration of the liquid medicine is 0.1-0.8%, the activity index, the seedling length, the root length, the fresh weight and the dry weight are obviously higher than those of a blank control. The results in Table 5 show that when the concentration of the thiamethoxam solution is 0.1-1.0%, the absorbed dosages of the seed coat and the seed kernel are gradually increased along with the increase of the concentration of the solution, the seed is soaked for 12 hours, and the absorbed dosages of the seed coat and the seed kernel are 8532.1-10324.2 mg/kg and 582.3-801.6 mg/kg respectively. The detection result of the dose of the thiamethoxam on the fresh leaves is as follows: sampling after 3 weeks of sowing, wherein the content of thiamethoxam in the leaves is higher to 16.3-32.5 mg/kg; the amount of the seed was measured again at 5 weeks and 7 weeks of sowing to be 12.3 mg/kg-28.6 mg/kg. The method is used for treating the seeds for 12 hours, and the thiamethoxam content is 0.1% -0.8%, so that the method can theoretically achieve a good prevention and treatment effect on cotton seedling aphids.

TABLE 4 comparison of germination rate and seedling quality results for thiamethoxam solution-treated seeds

TABLE 5 comparison of seed tape dosage results for thiamethoxam solution treatment

Storing the thiamethoxam solution at normal temperature and in a dry place to trigger the thiamethoxam solution back to the dried cotton seeds, wherein the germination rates are 52.4-85.2% and 50.3-86.1% respectively when the cotton seeds are stored for 3 months and 6 months, which indicates that the germination rates of the seeds are not influenced by the storage time.

Example 5 measurement of germination Rate and seedling growth index of seed after initiation of tributyl phosphate adjuvant back to dryness

Cotton seeds were treated as described in example 2, with tributyl phosphate adjuvant used at concentrations of 0.1%, 0.05%, 0.01%, 0.005%, 0.001%, and 0.0005%, treated by seed soaking for 12h, and allowed to dry back. The primed seeds were placed in an illumination incubator at ambient temperature (28 ℃, 12h illumination, 12h darkness, 60% relative humidity) for germination vigor, germination percentage, seedling length, root length, fresh weight and dry weight growth indicators, as detailed in table 6. When the concentration of the tributyl phosphate auxiliary agent is 0.01-0.05%, compared with a blank control, the germination vigor and the germination rate of the seeds are obviously improved. When the concentration of the tributyl phosphate auxiliary agent reaches 0.1%, the germination vigor and the germination rate of the seeds are obviously influenced and are reduced by 12.8% and 11.4% compared with the control. When the concentration of the tributyl phosphate auxiliary agent is 0.01-0.05%, the activity index, the seedling length, the root length, the fresh weight and the dry weight are all obviously higher than those of a blank control.

TABLE 6 comparison of germination rate and seedling quality results for seeds treated with tributyl phosphate adjuvant solution

Example 6 Effect of different agent treatments on Cotton seed Germination Rate and seedling growth

The effect of different pharmacological treatments on cotton seed germination and seedling growth was studied, wherein: treatment group 1:100mg/L gibberellin; treatment group 2: 0.2% of shrinkstone; treatment group 3: 0.2% thiamethoxam; treatment group 4: 100mg/L gibberellin + 0.2% Queensland; treatment group 5: 100mg/L gibberellin + 0.2% thiamethoxam; treatment group 6: the treated group was measured for the indexes of properties such as germination vigor, germination percentage, seedling length, root length, fresh weight and dry weight of gibberellin (100 mg/L), cinnabar (0.2%), shrinkstone (0.2%), and thiamethoxam (0.2%), and more specifically, examples 1 and 2 were referred to. The results are shown in Table 7, wherein the cotton seed germination rate, seedling length, fresh weight and dry weight of the treatment group 5 are higher than those of other treatment groups, which indicates that the combination of 100mg/L gibberellin and 0.2% thiamethoxam medicament has better effects on promoting the germination of cotton seeds and the growth of seedlings than the combination of 100mg/L gibberellin and 0.2% thiamethoxam single medicament, and is better than the treatment of 100mg/L gibberellin and 0.2% thiamethoxam single medicament.

TABLE 7 comparison of the germination rates and seedling growth effects of different combinations of agents on cotton seeds

Note: different lower case letters indicate significant differences between treatments at the 0.05 level.

Example 7 prevention and treatment Effect of any combination of gibberellin, thiamethoxam, tributyl phosphate or dibutyl sebacate on Cotton seedling stage pests

The types and the dosage of gibberellin, thiamethoxam and auxiliary agents are changed, the prevention and treatment effects of different medicament combinations on cotton seedling diseases and insect pests are researched, and the results are shown in table 8. The gibberellin dosage of the treatment groups 1 to 4 is 50mg/L, the thiamethoxam dosage is 0.2%, the dosage of a single auxiliary agent is 0.01% or 0.05%, the disease control effect is 31.5-35.2%, the aphid control effect is 82.4-86.2%, and the thrips control effect is 41.8-59.4%. If the dosage of gibberellin and thiamethoxam is doubled and the combined auxiliary agent is used, the disease control effect is increased to 45.5-50.2%, the aphid control effect is 92.2-93.1%, and the thrips control effect is 60.9-78.2%.

It should be noted that cotton emerges 6-8 days after sowing, and the seedling stage generally refers to the period from emergence to cotton flowering. The cotton seed initiator of the invention does not need to be applied in the early growth stage (namely seedling stage to flowering stage) of cotton, and the lasting period of the agent is as long as more than 80 days. The method can reduce the dosage of cotton in seedling stage, and realize cost saving and efficiency improvement.

TABLE 8 comparison of the effects of different combinations of agents on the diseases and pests in the seedling stage of cotton

The applicant researches and discovers that when the concentration of gibberellin agents in a cotton seed initiator is 50-400 mg/L, the concentration of thiamethoxam agents is 0.1-0.8%, and the concentration of auxiliaries (tributyl phosphate and/or dibutyl sebacate) is 0.01-0.05%, compared with a blank control, the emergence time of cotton seeds is advanced by 2 days, the cotton seed emergence control effect is 31.5-50.2%, the aphid control effect is 82.4-93.1%, the thrips control effect is 41.8-78.2%, the agent duration is more than 80 days, and no adverse effect is caused on cotton emergence.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A cotton seed initiator comprises a solute and a solvent, and is characterized in that the solute is a combination of gibberellin, thiamethoxam and an auxiliary agent,

the concentration of the gibberellin in the initiator is 50-400 mg/L, the concentration of the thiamethoxam in the initiator is 0.1-0.8%, the concentration of the auxiliary agent in the initiator is 0.01-0.05%,

the auxiliary agent is selected from at least one of tributyl phosphate and dibutyl sebacate.

2. The cotton seed initiator of claim 1, wherein the solvent is water and/or an organic solvent selected from at least one of ethanol and dimethyl sulfoxide.

3. A method of treating cotton seeds with the initiator of claim 1 or 2, comprising soaking the cotton seeds in the initiator and then drying the seeds, followed by sowing or storing the seeds for future use.

4. The method according to claim 3, wherein the soaking temperature is 25-30 ℃ and the soaking initiation time is 8-16 h.

5. The method according to claim 3, wherein the drying temperature is 35-50 ℃ and the drying time is 40-60 h.

6. The method of claim 3, wherein the seed coat of the cotton seed is sterilized prior to soaking with the initiating agent.

7. The method of claim 6, wherein the disinfection is performed by using 75% alcohol by volume for 5-20 min.

8. The method of claim 3, wherein after said soaking, the seeds are removed for water-controlled treatment and then dried back.