CN115211343A

CN115211343A - Tobacco seed breeding method

Info

Publication number: CN115211343A
Application number: CN202210890869.2A
Authority: CN
Inventors: 田峰; 滕凯; 张胜; 巢进; 田明慧; 毛辉
Original assignee: Xiangxi Autonomous Prefecture Company Hunan Tobacco Co ltd
Current assignee: Xiangxi Autonomous Prefecture Company Hunan Tobacco Co ltd
Priority date: 2022-07-27
Filing date: 2022-07-27
Publication date: 2022-10-21

Abstract

The invention discloses a tobacco seed breeding method, belonging to the technical field of tobacco breeding, comprising the following steps of (1) soaking seeds once: soaking tobacco seeds in water of 25-26 deg.C for 2-2.5h, taking out, covering tobacco seeds with wet cloth, treating for 20-24h, drying at 20-25 deg.C and 50% humidity for 10-12h, and taking out to obtain tobacco seeds soaked for one time; (2) secondary seed soaking: covering the tobacco seeds soaked for one time with wet filter paper, treating for 28-30h, taking out, sterilizing with 1wt% copper sulfate solution at 25 deg.C for 15min, taking out, and air drying the surface; (3) seed induction: soaking the seeds dried on the surface in an inducer to obtain induced tobacco seeds; and (4) pregermination: accelerating germination of the induced tobacco seeds for 1-2 days at 25-28 ℃, sowing after accelerating germination, improving germination uniformity of the tobacco seeds and stress resistance of the induced seeds, and breeding the tobacco seedlings with high activity.

Description

Tobacco seed breeding method

Technical Field

The invention relates to the technical field of tobacco breeding, in particular to a tobacco seed breeding method.

Background

Tobacco is one of the important economic crops in China, and is widely planted in various provinces in China. At present, two methods of seed propagation and tissue culture are mainly adopted as propagation methods of tobacco, wherein the seed propagation still belongs to the most important propagation method of tobacco propagation. In the breeding process of the tobacco seeds, the quality of the tobacco is the result of the combined action of the inheritance, the cultivation means and the ecological environment, and the vitality of the tobacco seeds is of great importance to the quality of the tobacco. The seed vigor is one of the important indexes for measuring the seed quality and is closely related to the field seedling emergence capability of tobacco seeds, so the improvement of the seed vigor is one of the difficulties to be overcome in the tobacco breeding technology.

The tobacco seeds with high activity have rapid field emergence, obvious growth advantages and strong stress resistance, and have great significance for producing high-quality tobacco leaves, but the activity of the tobacco seeds is influenced by self heredity and environmental conditions, so that the yield and the quality of the seeds are seriously influenced. At present, the conventional operation is mainly to treat the seeds by a chemical or physical method to promote germination, such as common plant hormone regulation, nutrient element regulation, light-temperature electric field treatment and the like, the treatment method is mainly to improve the germination rate of the seeds in a laboratory, and has reference significance for tobacco seed breeding in actual agricultural production. In the practical application of the method, not only should the germination rate of the seeds be considered, but also the uniformity of the germination of the seeds and the stress resistance of the seeds should be considered, so that the bred seedlings can be more suitable for the practical agricultural production.

Disclosure of Invention

In view of the above, the present invention provides a method for breeding tobacco seeds, which utilizes waste crops to prepare an inducer, combines with a seed soaking step to improve the uniformity of germination of the tobacco seeds and induce the stress resistance of the seeds, and breeds high-activity tobacco seedlings.

The invention solves the problems by the following technical scheme:

a method of tobacco seed propagation, the method comprising the steps of:

(1) Soaking seeds for one time: soaking tobacco seeds in water of 25-26 deg.C for 2-2.5h, taking out, covering tobacco seeds with wet cloth, treating for 20-24h, drying at 20-25 deg.C and 50% humidity for 10-12h, and taking out to obtain tobacco seeds soaked for one time;

(2) Secondary seed soaking: covering the tobacco seeds soaked for one time with wet filter paper, treating for 28-30h, taking out, sterilizing with 1wt% copper sulfate solution at 25 deg.C for 15min, taking out, and air drying the surface;

(3) Seed induction: soaking the seeds dried on the surface in an inducer to obtain induced tobacco seeds;

(4) Accelerating germination: accelerating germination of the tobacco seeds after induction is completed for 1-2 days at 25-28 ℃, and sowing can be performed after accelerating germination is completed.

Further, the wet cloth in the primary seed soaking in the step (1) is soaked by water, and the wet filter paper in the secondary seed soaking in the step (2) is prepared by mixing 0.2wt% of calcium hydroxide solution and 0.01wt% of boric acid solution according to a volume ratio of 1:1 mixed solution wetted.

Further, in the germination accelerating process, turning over for 1-2 times every day, and washing mucus on the surfaces of tobacco seeds by warm water at 20-25 ℃ during each turning over.

Further, the specific operations of the seed induction step are as follows:

firstly, soaking the seeds dried on the surface in an inducer at normal temperature for 1-2h, then placing the seeds in an environment of 10-15 ℃ for continuous induction for 40-60min, then placing the seeds in an environment of 5-8 ℃ for continuous induction for 10-15min, taking the seeds out, and then continuing the induction and soaking for 5-6h under the conditions of normal temperature and all day illumination to obtain the tobacco seeds subjected to induction.

Further, the illumination intensity of the whole day illumination is 1200-1500lx.

Further, the inducer comprises the following raw materials in parts by weight: 2-5 parts of infected wheat, 10-15 parts of safflower, 2-3 parts of guar gum, 0.1-0.5 part of sodium selenite, 0.1-0.3 part of choline chloride and 0.01-0.02 part of manganese sulfate.

Further, the preparation method of the inducer comprises the following steps:

(1) Soaking diseased wheat in 35-45 deg.C hot water for 20-30min, heating to boil, decocting for 10-20min, mixing with Carthami flos, cooling to room temperature, pulverizing, adding sodium selenite, standing for aging, centrifuging, and filtering to obtain filtrate;

(2) Mixing the obtained filtrate with choline chloride uniformly, adding manganese sulfate, stirring uniformly, adding guar gum, heating to 60-65 ℃, stirring for reacting for 10-15min, stopping heating, stirring, cooling to room temperature, standing overnight, adding water, and homogenizing to obtain the inducer.

Further, the disease-infected wheat is disease-infected wheat grains obtained from wheat plants infected with gibberellic disease.

Further, the safflower is the stem, leaf, flower of a fresh safflower plant.

According to the invention, the stress resistance and the seed activity of the seeds can be improved by combining the inducer in the seed breeding method, the cold resistance and the drought resistance of the seeds are further improved, and the germination uniformity of the tobacco seeds is improved. The wheat after being infected with diseases can not be eaten by people and livestock, because the wheat grains infected with diseases obtained from wheat plants infected with gibberellic disease have a large amount of toxins, such as estrogen-like hormone, fusarium graminearum, nivalenol and the like, but after being detoxified and sterilized, the wheat grains are mixed with safflower plant solution containing a large amount of phenols, sterols and polyamine substances and added into tobacco seeds, so that the activity of the tobacco seeds can be obviously improved. The membrane of the seeds is subjected to osmotic adjustment in the early stage after primary seed soaking and secondary seed soaking, so that an inducer can conveniently enter organelles and a membrane system, the filtrate prepared from infected wheat grains and safflower plants in the inducer promotes the activation of enzymes such as antioxidant enzyme and the like, the content of soluble sugar is increased, and meanwhile, the membrane plays a role in catalysis, is combined with a large amount of polycation characteristic substances contained in the inducer, is combined with protein on the membrane, maintains the acid-base balance of the seeds and the stability of the membrane, prevents the membrane from being disordered under the adverse condition, enhances the activity of the antioxidant enzyme, promotes the accumulation of proline, accelerates the respiration rate, further shortens the germination time, improves the germination vigor and simultaneously enhances the stress resistance of the seeds.

Has the advantages that:

the low-temperature cold damage or high-temperature drought can affect the germination of seeds, the emergence of seedlings and the growth of seedlings, and finally the quality and the yield of tobacco leaves are reduced, so that the improvement of the cold resistance and the drought resistance of tobacco seeds is of great significance, the improvement of the emergence uniformity can also further improve the yield and reduce the management difficulty, and the method is of great significance to actual production. Meanwhile, the diseased wheat can be utilized to carry out secondary utilization on waste crops or agricultural products, so that resources are saved.

Drawings

FIG. 1: germination patterns of seeds in the room temperature condition of example 1;

FIG. 2: germination pattern of seed under normal temperature conditions of comparative example 1.

Detailed Description

The invention will be described in detail with reference to specific embodiments and drawings, wherein:

example 1: preparation of inducer 1

(1) Soaking 0.2kg of fresh wheat grains obtained from wheat plants infected with gibberellic disease in 45 ℃ hot water for 20min, heating until the water is boiled, keeping the water boiling state for boiling for 10min, stopping heating, mixing with 1kg of safflower plants, wherein the safflower plants can comprise fresh stems, leaves and flowers, cooling to normal temperature after mixing wheat seeds and safflower plants, adding water for crushing, adding water until the total mass of water is 0.6 times of the total mass of the wheat seeds and the safflower plants, shading at normal temperature, adding 0.01kg of sodium selenite, stirring uniformly, standing for aging for 24h, filtering, centrifuging to obtain filtrate for later use;

(2) And uniformly mixing the prepared filtrate with 0.01kg of choline chloride, then adding 0.001kg of manganese sulfate, uniformly stirring, then adding 0.2kg of guar gum, heating to 60 ℃, stirring for reacting for 15min, stopping heating, stirring and cooling to room temperature, standing overnight, then adding 0.4kg of water, and homogenizing at 13000rpm to obtain the inducer.

Comparative example 1:

this comparative example is to be contrasted with example 1, where an inducer is prepared. The inducer is prepared by using diseased wheat grains and safflower plants as raw materials, and the preparation process of the inducer comprises the following steps:

750mL of clean water, 0.01kg of sodium selenite and 0.01kg of choline chloride are uniformly mixed, then 0.001kg of manganese sulfate is added, 0.2kg of guar gum is added after uniform stirring, the mixture is heated to 60 ℃, the heating is stopped after stirring reaction for 15min, the mixture is stirred and cooled to room temperature, 0.4kg of water is added after the mixture is kept stand for one night, and the inducer is obtained after homogenization at the rotating speed of 13000 rpm.

Comparative example 2:

this comparative example is to be contrasted with example 1, where an inducer is prepared. In this comparative example, the inducer was prepared without using diseased wheat grains as the starting material, and the inducer was prepared as follows:

(1) Mixing 1kg of Carthami flos plant (including fresh stem, leaf, and flower) with 0.6kg of water, pulverizing, adding 0.01kg of sodium selenite at room temperature under shade, stirring, standing, aging for 24 hr, filtering, and centrifuging to obtain filtrate;

step (2) is the same as in example 1.

Comparative example 3:

this comparative example is to be contrasted with example 1, where an inducer is prepared. The present comparative example does not use safflower as a raw material to prepare an inducer, and the inducer is prepared by the following process:

(1) Soaking 0.2kg of wheat seeds obtained from wheat plants infected with gibberellic disease in 45 deg.C hot water for 20min, heating until the water is boiling, keeping the water boiling state, boiling for 10min, stopping heating, standing, cooling to room temperature, adding 0.2kg of water, pulverizing, adding 0.01kg of sodium selenite at room temperature, stirring, standing, aging for 24h, filtering, and centrifuging to obtain filtrate;

step (2) is the same as in example 1.

Comparative example 4:

this comparative example is to be contrasted with example 1, where an inducer is prepared. This comparative example does not use sodium selenite as a raw material for the preparation of the inducer, which differs from the preparation process of example 1 only in that: in the comparative example, the treated wheat grains and the treated safflower plants are directly crushed and subjected to normal-temperature shady standing and aging for 24 hours, and the filtrate is prepared without adding sodium selenite.

Step (2) is the same as in example 1.

Comparative example 5:

this comparative example is to be contrasted with example 1, where an inducer is prepared. The inducer was prepared without using choline chloride as a starting material in this comparative example, and was prepared as follows:

the procedure for preparing the filtrate was the same as in example 1;

(2) Mixing the obtained filtrate with 0.001kg of manganese sulfate, stirring for dissolving, adding 0.2kg of guar gum, heating to 60 ℃, stirring for reacting for 15min, stopping heating, stirring and cooling to room temperature, standing overnight, adding 0.4kg of water, and homogenizing at 13000rpm to obtain the inducer.

Comparative example 6:

this comparative example is to be contrasted with example 1, where an inducer is prepared. The inducer was prepared without using manganese sulfate as a raw material in this comparative example, and the preparation process of the inducer was as follows:

the procedure for preparing the filtrate was the same as in example 1;

(2) And uniformly mixing the prepared filtrate with 0.01kg of choline chloride, adding 0.2kg of guar gum, heating to 60 ℃, stirring for reacting for 15min, stopping heating, stirring and cooling to room temperature, standing overnight, adding 0.4kg of water, and homogenizing at 13000rpm to obtain the inducer.

Comparative example 7:

this comparative example is to be contrasted with example 1, where an inducer is prepared. The comparative example did not use guar gum as the raw material to prepare the inducer, which was prepared as follows:

the procedure for preparing the filtrate was the same as in example 1;

(2) And uniformly mixing the prepared filtrate with 0.01kg of choline chloride, then adding 0.001kg of manganese sulfate, and uniformly stirring to obtain the inducer.

Example 2: preparation of inducer II

(1) Soaking fresh wheat seeds obtained from 0.3kg of wheat plants infected with gibberellic disease in hot water at 40 ℃ for 25min, heating until the water is boiled, keeping the water boiling state for 15min, stopping heating, mixing with 1.2kg of safflower plants, wherein the safflower plants can comprise fresh stems, leaves and flowers, cooling to normal temperature after the wheat seeds and the safflower plants are mixed, adding water for crushing, adding water until the total mass of water is 0.6 times of the total mass of the wheat seeds and the safflower plants, shading at normal temperature, adding 0.03kg of sodium selenite, stirring uniformly, standing for aging for 24h, filtering, and centrifuging to obtain filtrate for later use;

(2) And uniformly mixing the prepared filtrate with 0.02kg of choline chloride, then adding 0.002kg of manganese sulfate, uniformly stirring, then adding 0.25kg of guar gum, heating to 60 ℃, stirring to react for 13min, stopping heating, stirring and cooling to room temperature, standing overnight, then adding 0.5kg of water, and homogenizing at 13000rpm to obtain the inducer.

Example 3: preparation of inducer III

(1) Soaking fresh wheat seeds obtained from 0.5kg of wheat plants infected with gibberellic disease in hot water at 35 ℃ for 30min, heating until the water is boiled, keeping the water boiling state for boiling for 20min, stopping heating, mixing with 1.5kg of safflower plants, wherein the safflower plants can comprise fresh stems, leaves and flowers, cooling to normal temperature after the wheat seeds and the safflower plants are mixed, adding water for crushing, adding water until the total mass of the water is 0.6 times of the total mass of the wheat seeds and the safflower plants, shading at normal temperature, adding 0.05kg of sodium selenite, stirring uniformly, standing for aging for 24h, filtering, and centrifuging to obtain filtrate for later use;

(2) And uniformly mixing the prepared filtrate with 0.03kg of choline chloride, then adding 0.002kg of manganese sulfate, uniformly stirring, then adding 0.3kg of guar gum, heating to 65 ℃, stirring for reacting for 10min, stopping heating, stirring and cooling to room temperature, standing overnight, then adding 0.6kg of water, and homogenizing at 13000rpm to obtain the inducer.

Example 4: tobacco planting and breeding method

(1) Soaking seeds for one time: soaking tobacco seeds in water at 25 ℃ for 2.5h, taking out, covering the tobacco seeds with wet cloth soaked with water, covering at normal temperature for 24h, drying at 20 ℃ and 50% humidity for 12h, and taking out to obtain tobacco seeds subjected to primary seed soaking;

(2) Secondary seed soaking: mixing 0.2wt% of calcium hydroxide solution and 0.01wt% of boric acid solution according to a volume ratio of 1:1 to obtain a mixed solution, and soaking the filter paper by using the mixed solution to obtain wet filter paper; covering the tobacco seeds soaked for the first time with wet filter paper, treating at normal temperature for 28h, taking out, sterilizing with 1wt% copper sulfate solution at 25 deg.C for 15min, taking out, and air drying the tobacco seeds with clear water;

(3) Seed induction: soaking the seeds with the air-dried surfaces in an inducer at normal temperature for 2 hours, then placing the seeds in an environment at 15 ℃ for continuous induction for 40 minutes, then placing the seeds in an environment at 5 ℃ for continuous induction for 10 minutes, taking the seeds out, and then continuing the induction and soaking for 6 hours under the conditions of normal temperature and illumination intensity of 1200lx all day illumination to obtain the tobacco seeds with the induction completion;

(4) Accelerating germination: accelerating germination of the tobacco seeds after induction is carried out for 2 days at 25-28 ℃, turning over for 1-2 times every day in the accelerating germination process, washing mucus on the surfaces of the tobacco seeds by warm water at 20-25 ℃ during each turning over, and sowing after accelerating germination is finished.

Comparative example 8:

the comparison example is compared with the example 4, the difference is the change of the planting and breeding steps, and the specific process of the comparison example is as follows:

(1) Soaking seeds for one time: soaking the tobacco seeds in water at 25 ℃ for 5 hours, taking out the tobacco seeds, and taking out the tobacco seeds to obtain the tobacco seeds subjected to primary seed soaking;

step (2) to step (4) were the same as in example 4.

Comparative example 9:

this comparative example is compared with example 4, with the difference that the planting and breeding steps are changed, and the specific process of this comparative example is as follows:

(1) Soaking seeds for one time: soaking tobacco seeds in water at 25 ℃ for 2.5h, taking out, covering the tobacco seeds with wet cloth soaked with water, covering at normal temperature for 24h, drying at 20 ℃ and 50% humidity for 12h, and taking out to obtain tobacco seeds soaked for one time;

(2) Secondary seed soaking: soaking the filter paper with clear water to obtain wet filter paper, covering the tobacco seeds soaked for one time with the wet filter paper, treating at normal temperature for 28h, taking out, sterilizing with 1wt% copper sulfate solution at 25 deg.C for 15min, taking out, and air drying the tobacco seeds surface with clear water;

steps (3) to (4) were the same as in example 4.

Comparative example 10:

(1) Soaking seeds at one time: soaking tobacco seeds in water at 25 ℃ for 2.5h, taking out, covering the tobacco seeds with wet cloth soaked with water, covering at normal temperature for 24h, drying at 20 ℃ and 50% humidity for 12h, and taking out to obtain tobacco seeds subjected to primary seed soaking;

(2) Secondary seed soaking: mixing 0.2wt% of calcium hydroxide solution and 0.01wt% of boric acid solution according to a volume ratio of 1:1 to obtain a mixed solution, and soaking filter paper by using the mixed solution to obtain wet filter paper; covering the tobacco seeds subjected to primary seed soaking with wet filter paper, treating at normal temperature for 28h, taking out, sterilizing with 1wt% copper sulfate solution at 25 deg.C for 15min, taking out, and air drying the surface of the tobacco seeds with clear water;

(3) Seed induction: soaking the seeds with the air-dried surfaces in an inducer for 9 hours at normal temperature to obtain tobacco seeds subjected to induction;

Comparative example 11:

(3) Seed induction: foaming in clear water for 2h at normal temperature to obtain tobacco seeds subjected to induction;

1. Normal temperature, low temperature, drought induced germination experiment:

the inducer prepared in example 1 and comparative examples 1-7 is used in a K326 tobacco seed breeding experiment, the breeding process refers to example 4, the inducer is replaced by clear water in a blank control, plug trays are selected for planting, 100 tobacco seeds are planted in each plug tray (no seeds are placed in the upper left corner of the plug tray), each plug tray is one, 3 are repeated, and the test result is an average value.

1. And (3) normal-temperature germination test: after the germination is finished, continuously culturing under the conditions of 25-28 ℃ of temperature, 80-85% of relative humidity, 1200lx illumination intensity and 8 h/day of illumination time, counting the number of days for germination, the germination duration and the final germination rate and germination vigor, starting to develop cotyledons, and normally developing radicles to be the germination standard, wherein the obtained data are shown in table 1:

TABLE 1

	Days of onset of germination	Duration of germination (Tian)	Germination percentage (%)	Germination vigor (%)
					Example 1	5.0	12.1	98.7	96.7
Comparative example 1	6.1	15.0	92.3	75.0
					Comparative example 2	5.9	14.7	93.3	76.3
Comparative example 3	5.8	14.6	93.7	77.3
					Comparative example 4	5.6	13.2	96.3	78.3
Comparative example 5	5.5	13.1	96.7	78.7
					Comparative example 6	5.1	12.7	97.3	89.7
Comparative example 7	5.0	13.0	97.7	92.0
					Blank control	6.7	15.3	90.7	70.3

2. And (3) low-temperature germination test: after the germination is finished, continuously culturing under the conditions of 10-11 ℃ of temperature, 80-85% of relative humidity, 1200lx illumination intensity and 8 h/day of illumination time, counting the number of days for germination, the germination duration and the final germination rate and germination vigor, starting to develop cotyledons, and normally developing radicles to be the germination standard, wherein the obtained data are shown in table 2:

TABLE 2

3. Drought germination test: when the tobacco seeds after germination acceleration are placed on culture dishes padded with two layers of filter paper, 2mL of 15% PEG-6000 is added into each culture dish to simulate drought, the formed water potential is about-0.4 Mpa, the culture is carried out under the conditions that the temperature is 25-28 ℃, the relative humidity is 80-85%, the illumination intensity is 1200lx and the illumination time is 8 h/day, the number of days for germination starting, the germination duration time and the final germination rate and germination potential are counted, the cotyledon is unfolded, and the normal development of radicles is taken as the standard of germination, and the obtained data are shown in Table 3:

TABLE 3

	Days of onset of germination	Duration of germination (Tian)	Percentage of germination (%)	Germination vigor (%)
					Example 1	5.9	14.3	94.7	60.7
Comparative example 1	8.0	18.7	78.3	28.3
					Comparative example 2	7.4	18.3	77.7	29.3
Comparative example 3	7.5	16.3	84.3	46.7
					Comparative example 4	6.3	15.3	84.7	45.7
Comparative example 5	6.1	15.7	87.3	46.0
					Comparative example 6	6.0	14.3	87	45.3
Comparative example 7	6.0	14.7	86.3	45.0
					Blank control	10.2	19.7	79.9	27.0

2. Seedling quality test under conditions of normal temperature, low temperature and drought:

the breeding methods of example 4 and comparative examples 8-11 were subjected to tobacco seedling growth tests. Each group of tobacco seeds had 100 seeds and 3 replicates, and the test results were the average.

1. And (3) normal-temperature germchit quality test: the seeds after the germination acceleration are continuously cultured for 30 days under the conditions of the temperature of 25-28 ℃, the relative humidity of 80-85%, the illumination intensity of 1200lx and the illumination time of 8 h/day, 10 plants are randomly selected from each group to measure the average root length, the seedling height, the full length and the seedling dry weight, and the obtained results are shown in table 4:

TABLE 4

	Root length (cm)	Miao height (cm)	Full length (cm)	Miao Dry weight (mg/100 strain)
					Example 4	9.71	6.27	15.98	176
Comparative example 8	9.35	5.84	15.19	153
					Comparative example 9	8.76	5.16	13.92	142
Comparative example 10	9.65	5.93	15.58	161
					Comparative example 11	7.67	4.98	12.65	139

2. And (3) low-temperature seedling quality test: after germination is completed, the seedlings are continuously cultured for 30 days under the conditions of 10-11 ℃ of temperature, 80-85% of relative humidity, 1200lx illumination intensity and 8 h/day of illumination time, 10 plants in each group are randomly selected to measure the average root length, the seedling height, the full length and the seedling dry weight, and the obtained results are shown in table 5:

TABLE 5

	Root length (cm)	Miao height (cm)	Full length (cm)	Miao Dry weight (mg/100 strain)
					Example 4	6.98	4.92	11.9	151
Comparative example 8	6.77	3.59	10.36	130
					Comparative example 9	5.34	3.41	8.75	114
Comparative example 10	6.04	4.71	10.75	137
					Comparative example 11	4.93	3.08	8.01	101

2. Drought seedling quality test: when the tobacco seeds after germination acceleration are placed on culture dishes padded with two layers of filter paper, 2mL of 15% PEG-6000 is added into each culture dish to simulate drought, the formed water potential is about-0.4 Mpa, the tobacco seeds are cultured for 30 days under the conditions that the temperature is 25-28 ℃, the relative humidity is 80-85%, the illumination intensity is 1200lx and the illumination time is 8 h/day, 10 plants are randomly selected from each group to measure the average root length, the seedling height, the full length and the seedling dry weight, and the obtained results are shown in Table 6:

TABLE 6

Data analysis was performed according to the results of tables 1-6:

1. tables 1-3 show the results of germination induction experiments conducted on tobacco seeds under different inducer conditions. According to the results, the induction agent prepared in example 1 has the best effect of inducing the germination of the tobacco seeds under the breeding method disclosed by the invention, the germination rate at normal temperature reaches 98.7%, and the germination potential reaches 96.7%, as shown in the early tobacco seed germination result in fig. 1, the induction agent can improve the germination rate of the seeds and simultaneously improve the germination potential, the activity of the seeds is high, the emergence is fast and regular, and the emergence result is high.

Under the conditions of low-temperature stress and drought stress, the germination rates of the tobacco seeds in example 1 after induction by the inducer respectively reach 90.3% and 94.7%, the germination potentials of the tobacco seeds are respectively 52.7% and 60.7% and are obviously higher than those of the blank control group by 83.3% and 79.9%, and the germination potentials of the tobacco seeds are respectively 27.3% and 27%, so that the resistance of the tobacco seeds to low-temperature stress and drought stress in the germination process is improved by the inducer, and the tobacco seeds have obvious stress resistance and germination advantages.

In addition, the germination initiation days and the germination duration of example 1 are shorter than those of the blank control, which shows that the germination speed is obviously higher, the dormancy period is shortened, and the seed vigor and the germination quality are obviously improved after the inducer is used.

2. Comparative examples 1 to 7 were compared with the inducer prepared in example 1, wherein the germination pattern induced at normal temperature of comparative example 1 is shown in fig. 2, and it can be seen that the seedlings were not uniform and the germination was seriously irregular. Wherein, the comparative example 1 is that the inducer is not added with infected wheat and safflower plants, the comparative example 2 is that the inducer is not added with infected wheat, the comparative example 3 is that the inducer is not added with infected wheat, the germination effect is worse in the comparative example, the total germination days are as low as 20.4 days and as high as 21.1 days, the total germination days are as high as 26.8 days under low-temperature stress, and the total germination days are as high as 26.7 days under drought stress. And in the comparative examples 4 to 7, sodium selenite, manganese sulfate and guar gum are not added, so that the problems of long germination duration and low germination potential are caused, and the fact that various germs, polyamine, phenols and other substances contained in diseased wheat and safflower plants are combined with cations in other raw materials of an inducer to act on tobacco seeds directly influences the vitality and stress resistance of the seeds is solved.

3. As can be seen from the seedling quality tests under the conditions of normal temperature, low temperature and drought, the method of the embodiment 4 for breeding the tobacco seedlings can obviously improve the root length, the seedling height, the full length and the dry weight of the seedlings, which shows that the growth vigor of the seedlings is better, and can obviously reduce the influence of freeze injury or drought on the seedlings, namely, the stress resistance of the seeds is better, so that the germinated seedlings have stronger capacity of resisting high and low temperature stress. The comparative example 8 is not dried in the primary seed soaking, the comparative example 9 is used for treating the seeds by using clear water filter paper directly in the secondary seed soaking, the comparative example 10 is not used for inducing the seeds by adopting an intermittent induction method, the comparative example 11 is used for inducing the seeds directly by using clear water, and the table 4-6 shows that the clear water induction effect of the comparative example 11 is the worst, which indicates that the seedlings are weak in growth and poor in stress resistance after the seeds which are not induced by the inducer germinate; comparative example 10 in which the seedlings were directly soaked with the inducer and were not treated with water intermittently, the seedlings were still weaker than those in example 4 in growth vigor and stress resistance, and could not develop stably at high and low temperatures. Comparative examples 8 and 9 facilitate the entry of an inducer for promoting the membrane of the seeds to perform the osmotic adjustment, and if the membrane system is not improved, the inducer is difficult to enter, the activity of the seeds is difficult to adjust or various physiological and biochemical indexes are difficult to improve, i.e. the stress of adverse conditions on the germination of the seeds is difficult to relieve, so that the seedling quality is poor.

Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims. The techniques, shapes, and configurations not described in detail in the present invention are all known techniques.

Claims

1. A method for breeding tobacco seeds, which is characterized by comprising the following steps:

(1) Soaking seeds at one time: soaking tobacco seeds in water of 25-26 deg.C for 2-2.5h, taking out, covering tobacco seeds with wet cloth, treating for 20-24h, drying at 20-25 deg.C and 50% humidity for 10-12h, and taking out to obtain tobacco seeds soaked for one time;

(2) Secondary seed soaking: covering the tobacco seeds soaked for the first time with wet filter paper, treating for 28-30h, taking out, sterilizing with 1wt% copper sulfate solution at 25 deg.C for 15min, taking out, and air drying the surface;

(3) Seed induction: soaking the seeds with the air-dried surfaces in an inducer to obtain induced tobacco seeds;

2. The method for breeding tobacco seeds as claimed in claim 1, wherein the wet cloth in the first seed soaking in step (1) is soaked by water, and the wet filter paper in the second seed soaking in step (2) is prepared by mixing 0.2wt% calcium hydroxide solution and 0.01wt% boric acid solution according to a volume ratio of 1:1 mixed solution wetted.

3. The method for breeding the tobacco seeds as claimed in claim 1, wherein the germination process comprises turning over for 1-2 times a day, and warm water of 20-25 ℃ is adopted to wash mucus on the surfaces of the tobacco seeds during each turning over.

4. The method for breeding tobacco seeds as claimed in claim 1, wherein the seed inducing step is specifically operated as follows:

soaking the seeds with the air-dried surface in an inducer at normal temperature for 1-2h, placing the seeds in an environment of 10-15 ℃ for continuous induction for 40-60min, then placing the seeds in an environment of 5-8 ℃ for continuous induction for 10-15min, taking the seeds out, and continuing the induction soaking for 5-6h under the conditions of normal temperature and all day illumination to obtain the tobacco seeds with the induction completed.

5. The method for breeding tobacco seeds as claimed in claim 4, wherein the illumination intensity of the whole day illumination is 1200-1500lx.

6. The method for breeding tobacco seeds as claimed in claim 1, wherein the inducer comprises the following raw materials by weight: 2-5 parts of infected wheat, 10-15 parts of safflower, 2-3 parts of guar gum, 0.1-0.5 part of sodium selenite, 0.1-0.3 part of choline chloride and 0.01-0.02 part of manganese sulfate.

7. The method for breeding tobacco seeds as claimed in claim 6, wherein the inducer is prepared by the following steps:

(1) Soaking diseased wheat in 35-45 deg.C hot water for 20-30min, heating to boil, decocting for 10-20min, mixing with Carthami flos, cooling to room temperature, pulverizing, adding sodium selenite, standing, aging for 24-36 hr, centrifuging, and filtering to obtain filtrate;

(2) And uniformly mixing the obtained filtrate with choline chloride, then adding manganese sulfate, uniformly stirring, then adding guar gum, heating to 60-65 ℃, stirring to react for 10-15min, stopping heating, stirring and cooling to room temperature, standing overnight, then adding water, and homogenizing to obtain the inducer.

8. The method of claim 7, wherein the infected wheat is wheat grain infected with gibberellic disease.

9. The method of claim 8, wherein the safflower is stem, leaf, flower of a fresh safflower plant.