A method for cultivating a new variety that breaks the self-incompatibility of Taraxacum kok-saghyz

Abstract

The present invention provides a new variety cultivation method for breaking the self-incompatibility of Taraxacum kok-saghyz by means of root segment asexual rapid propagation technology. By controlling factors such as moisture, temperature, and exogenous hormones in the environment, the purpose of rapidly asexually propagating multiple plants from a single Taraxacum kok-saghyz plant is achieved. The method is simple, has low requirements for the experimental environment, and has a fast seedling formation rate, with the seedling formation rate reaching over 80%. At the same time, multiple plants propagated by rapid propagation are isolated for free pollination, enabling different plants with the same genotype to freely mate, which can solve the problem of breaking the self-incompatibility of Taraxacum kok-saghyz, and establishes a new implementation path and method for the purification of Taraxacum kok-saghyz strains and the breeding of new varieties, and has great potential development value for the large-scale cultivation of Taraxacum kok-saghyz.

Description

Technical Field

[0001] The present invention belongs to the field of biotechnology, specifically to the technical field of rubber grass breeding, and more specifically to the technical field of a new variety cultivation method and application for breaking the self-incompatibility of rubber grass through root segment asexual rapid propagation technology. Technical Background

[0002] Natural rubber, together with iron and steel, coal, and petroleum, is known as the four major basic raw materials and is a very important strategic resource. Currently, China's consumption of natural rubber is about 6 million tons, accounting for more than 40% of the global share. Among them, the domestic output accounts for only 13% of the consumption, and the external dependence is more than 80%. Natural rubber is mainly produced from the Hevea brasiliensis that is only suitable for planting in the hot and humid tropical rainforest areas. However, the area suitable for the growth of Hevea brasiliensis in China is very limited. Therefore, natural rubber has always been an important agricultural product restricting China's economic development and strategic security. Rubber grass (Taraxacum koksaghyz Rodin, TKS, also known as Russian dandelion or blue rubber dandelion) is a perennial herb of the genus Taraxacum in the Compositae family. It is native to Kazakhstan, Kyrgyzstan, Russia, and Xinjiang, China. Due to its high natural rubber content in the roots, excellent quality, strong adaptability and many other advantages, it has become a very promising rubber substitute crop for Hevea brasiliensis. Rubber grass has the characteristics of wide adaptability, short rubber production cycle, easy mechanized operation, and can effectively utilize saline-alkali land. It is an advantageous crop that can solve the long-term shortage of self-sufficiency of natural rubber in China and has potential development value.

[0003] The chromosome number of rubber grass is 2n = 16, and it has perfect flowers that can form normal female and male gametes. However, it cannot set seeds at all during self-pollination, which has a great impact on the variety selection and breeding of rubber grass. Summary of the Invention

[0004] Aiming at the problem that the prior art currently cannot set seeds at all during the self-pollination of rubber grass, which has a great impact on the variety selection and breeding of rubber grass, the present invention controls factors such as moisture, temperature, and exogenous hormones in the environment to achieve the purpose of rapidly asexually propagating multiple plants from a single rubber grass plant, realizing the self-mating of different plants with the same genotype, and being able to solve the problem of breaking the self-incompatibility of rubber grass. The method is simple, has low requirements for the experimental environment, and has fast seedling emergence and high seedling emergence rate. It has great potential development value for the large-scale cultivation of rubber grass.

[0005] In order to achieve the purpose of the present invention, the technical solution of the present invention is as follows:

[0006] The present application provides a new variety cultivation method for breaking the self-incompatibility of rubber grass, and the cultivation method is obtained by the following steps:

[0007] (1). Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of the Taraxacum kok-saghyz Rodin with clean water, remove the leaves above the ground, completely peel off all the rotten outer tissues of the roots, cut the roots of the Taraxacum kok-saghyz Rodin with a diameter of more than 1 mm into root segments of 1 - 2 cm, neatly arrange them in the Petri dish according to the upper and lower ends of morphology, treat them with plant hormones, and leave them overnight.

[0008] (2). Add clean water to a commercially available vegetable seedling-raising special substrate mainly composed of peat and mix well until it is appropriate that when you grab the substrate and make it into a ball and drop it on the ground, it naturally scatters. Then fill the plastic flower pots or 72-hole seedling trays with the mixed substrate. Place the flower pots or seedling trays filled with the substrate in a tray about 5 cm deep. Take out the overnight-treated root segments of the Taraxacum kok-saghyz Rodin in step (1) and insert the lower ends into the seedling-raising substrate according to the upper and lower ends of morphology, with the upper ends exposed about 0.5 cm above the substrate.

[0009] (3). Fill the tray in which the root segments of the Taraxacum kok-saghyz Rodin have been cut and inserted in step (2) with water. The substrate will absorb water from the tray to maintain an appropriate humidity of the substrate, which is beneficial for the Taraxacum kok-saghyz Rodin to take root. After filling with water, a commercially available transparent film can be used to completely cover the flower pots or seedling trays. Make several evenly distributed holes in the film for ventilation, which can effectively ensure that the upper growth points of the root segments will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25 - 28 °C to reduce the excessive evaporation of water caused by direct sunlight.

[0010] (4). Observe the germinated Taraxacum kok-saghyz Rodin tissue after cutting in step (3), and appropriately irrigate according to the evaporation of water in the tray before the Taraxacum kok-saghyz Rodin germinates.

[0011] (5). Observe that the root segments of the Taraxacum kok-saghyz Rodin in step (4) generally differentiate into leaf bud primordia in about 7 days, grow yellow and nearly transparent new leaves in about 13 days, and the leaves turn green to form new leaves of the Taraxacum kok-saghyz Rodin in about 16 days. Generally, more than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow continuously on the roots, and new Taraxacum kok-saghyz Rodin plants gradually grow. When the yellow and nearly transparent new leaves grow, the irrigation should be reduced. If there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate to avoid the new plants of the Taraxacum kok-saghyz Rodin being infected by mold and rotting and dying due to too high humidity.

[0012] (6). Transplant the rapidly propagated Taraxacum kok-saghyz Rodin in step (5) to the experimental field after about 45 days. The root systems of the Taraxacum kok-saghyz Rodin plants at about 16 days have not developed completely. The soil humidity should be controlled at about 30%, and the temperature should be 25 - 28 °C. Continue to grow for about 20 days, and then transfer them to outdoor hardening-off and wait for transplantation.

[0013] (7) Around 45 days after cultivation in step (6), the roots of the Taraxacum kok-saghyz have fully wrapped the seedling substrate. Take out the Taraxacum kok-saghyz seedlings together with the seedling substrate, transplant them into the experimental plot, cover with a sunshade net, and water thoroughly. The Taraxacum kok-saghyz seedlings will survive after about 7 days of slow seedling growth, and the sunshade net can be removed;

[0014] (8) When the Taraxacum kok-saghyz treated in step (6) is budding, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different materials of Taraxacum kok-saghyz. Every morning from 10:00 to 12:00, when the flowers of Taraxacum kok-saghyz are fully open and the stigma is in a "Y" shape, manually assist in pollination. Seeds can be harvested about 12 days after flowering;

[0015] (9) Select materials by the methods described in steps (1) to (8) above, perform multi-generation asexual rapid propagation, and finally achieve the purification of Taraxacum kok-saghyz materials. Mix and freely mate the inbred lines with similar agronomic traits and high rubber content to obtain a new high-quality variety of Taraxacum kok-saghyz.

[0016] Further, the plant hormones can be gibberellin, indoleacetic acid, and indolebutyric acid.

[0017] Furthermore, the plant hormones can be gibberellin, indoleacetic acid, and indolebutyric acid respectively, with a concentration of 80 - 240 mg / L.

[0018] Preferably, the plant hormones can be gibberellin, indoleacetic acid, and indolebutyric acid respectively, with a concentration of 160 mg / L.

[0019] Preferably, the plant hormones can be gibberellin with a concentration of 16 - 240 mg / L and indolebutyric acid with a concentration of 80 - 240 mg / L.

[0020] More preferably, the plant hormones can be gibberellin with a concentration of 160 mg / L and indolebutyric acid with a concentration of 240 mg / L.

[0021] Furthermore, the present application also provides the application of the new variety cultivation method for breaking the self-incompatibility of Taraxacum kok-saghyz in the cultivation of new varieties of Taraxacum kok-saghyz.

[0022] By adopting the technical solutions provided above, the present invention obtains the following beneficial effects:

[0023] (1) The present invention provides a new variety cultivation method for breaking the self-incompatibility of Taraxacum kok-saghyz through root segment asexual rapid propagation technology. By controlling factors such as moisture, temperature, and exogenous hormones in the environment, the purpose of rapidly asexually propagating multiple plants from a single Taraxacum kok-saghyz plant is achieved.

[0024] (2) By applying the new variety cultivation method for breaking the self-incompatibility of Taraxacum kok-saghyz through the asexual rapid propagation technology of root segments provided by the present application, the operation method is simple, the requirements for the experimental environment are low, the seedlings grow fast, and the seedling formation rate reaches over 80%. At the same time, multiple plants propagated by rapid propagation are isolated for free pollination to enable the free mating of different plants with the same genotype, which can solve the problem of breaking the self-incompatibility of Taraxacum kok-saghyz, establish a new implementation path and method for the purification of Taraxacum kok-saghyz strains and the breeding of new varieties, and has great potential development value for the large-scale cultivation of Taraxacum kok-saghyz. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The figure shows the influence of different concentrations of gibberellin on the germination and rooting rates of root segments at different parts.

[0026] Figure 2 The figure shows the influence of different concentrations of indoleacetic acid on the germination and rooting rates of root segments at different parts.

[0027] Figure 3 The figure shows the influence of different concentrations of indolebutyric acid on the germination and rooting rates of root segments at different parts.

[0028] Figure 4 The figure shows the experimental result diagram of the control group.

[0029] Figure 5 The figure shows the influence of different concentrations of GA3 + IBA on the germination and rooting rates of root segments at different parts.

[0030] Figure 6 The figure shows the examples of asexual rapid propagation of root segments. Among them, Figure A shows the selection of a single Taraxacum kok-saghyz plant; Figure B shows the root of Taraxacum kok-saghyz cut and placed in a petri dish lined with filter paper; Figure C shows that after about 7 days of cutting and culturing, the leaf bud primordium appears initially; Figure D shows that new yellow and nearly transparent leaves grow after about 13 days; Figure E shows that the leaves turn green to form new leaves of Taraxacum kok-saghyz after about 16 days.

[0031] Figure 7 The figure shows the on-site diagram of the propagation of Taraxacum kok-saghyz root segments.

[0032] Figure 8 The figure shows the diagram of isolated pollination of Taraxacum kok-saghyz in a screen house.

[0033] Figure 9 The figure shows the observation of the flowering habit and pollination diagram of Taraxacum kok-saghyz. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The following examples are used to further illustrate the content of the present invention, but should not be construed as a limitation to the present invention. Without departing from the spirit and essence of the present invention, any modification or replacement made to the method, steps or conditions of the present invention shall fall within the scope of the present invention.

[0035] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods. Unless otherwise specified, the materials, reagents, etc. used in the following examples can all be obtained from commercial channels.

[0036] Example 1: A new variety cultivation method for breaking the self-incompatibility of Taraxacum kok-saghyz

[0037] Please provide a new variety cultivation method for breaking the self-incompatibility of Taraxacum kok-saghyz. The cultivation method is obtained by the following steps:

[0038] (1) Take a culture dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the culture dish. Select excellent single plants of Taraxacum kok-saghyz that meet the breeding goals, wash the soil on the roots of Taraxacum kok-saghyz with clean water, remove the above-ground leaves, completely peel off all the rotten outer root tissues, cut the roots of Taraxacum kok-saghyz with a diameter of more than 1 mm into root segments of 1-2 cm, neatly place them in the culture dish according to the upper and lower ends of morphology, treat them with plant hormones, and let them stand overnight;

[0039] (2) Add clean water to the special vegetable seedling raising substrate mainly composed of peat moss on the market and mix well until it is appropriate to grab the substrate and form a ball and then naturally disperse when dropped on the ground. Then fill the plastic flower pot or 72-hole seedling plug tray with the mixed substrate. Place the flower pot or seedling plug tray filled with the substrate in a tray about 5 cm deep. Take out the overnight-treated root segments of Taraxacum kok-saghyz in step (1) and insert the lower ends into the seedling raising substrate according to the upper and lower ends of morphology, with the upper ends exposed about 0.5 cm above the substrate;

[0040] (3) Fill the tray in which the root segments of Taraxacum kok-saghyz have been cut in step (2) with water. The substrate will absorb water from the tray to maintain appropriate humidity of the substrate, which is beneficial for the roots of Taraxacum kok-saghyz to take root; after filling with water, the flower pot or seedling plug tray can be completely covered with commercially available transparent film, and several holes are evenly punched in the film to facilitate ventilation, which can effectively ensure that the upper growth points of the root segments will not lose water too quickly and affect germination; under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28 °C to reduce the excessive evaporation of water caused by direct sunlight;

[0041] (4) Observe the germinated Taraxacum kok-saghyz tissue after cutting in step (3), and appropriately irrigate the Taraxacum kok-saghyz before germination according to the water evaporation situation in the tray;

[0042] (5) Observe that the rubber grass root segments in step (4) generally differentiate leaf bud primordia in about 7 days, grow new yellow and nearly transparent leaves in about 13 days, and the leaves turn green to form new leaves of rubber grass in about 16 days; generally, more than 80% of the root segments will grow new leaves within this time, new root hairs also grow successively on the roots, and new rubber grass plants gradually grow; when new yellow and nearly transparent leaves grow, the watering should be reduced. If there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate, so as to avoid the new rubber grass plants being infected with mold and rotting and dying due to too high humidity;

[0043] (6) Transplant the rapidly propagated rubber grass in step (5) to the experimental field in about 45 days; the root systems of rubber grass plants at about 16 days have not developed completely, and the soil humidity should be controlled at about 30%, and the temperature should be 25 - 28 °C. Continue to grow for about 20 days, and then transfer to outdoor hardening off to wait for transplantation.

[0044] (7) After cultivating the rubber grass in step (6) for about 45 days, the root system has fully wrapped the seedling-raising substrate. Take out the rubber grass seedlings together with the seedling-raising substrate and transplant them into the experimental plot. Cover with a sunshade net and water thoroughly. The rubber grass survives the slow seedling stage in about 7 days, and the sunshade net can be removed;

[0045] (8) When the rubber grass in step (6) is in budding stage, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different rubber grass materials. Every morning from 10 o'clock to 12 o'clock, when the rubber grass flowers are fully open and the stigma is in a "Y" shape, manually assist in pollination. Seeds can be harvested about 12 days after flowering;

[0046] (9) Select materials by the methods described in steps (1) to (8) above, and perform multi-generation asexual rapid propagation to finally achieve the purification of rubber grass materials. Mix and freely mate the inbred lines with similar agronomic traits and relatively high rubber content to obtain a new high-quality rubber grass variety.

[0047] Example 2: A method for cultivating a new variety to break the self-incompatibility of rubber grass

[0048] Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of Taraxacum kok-saghyz Rodin with clean water, remove the above-ground leaves, completely peel off all the rotten outer root tissues, cut the Taraxacum kok-saghyz Rodin roots with a diameter of more than 1 mm into root segments of 1 - 2 cm with a sharp blade, neatly arrange them in the Petri dish according to the upper and lower ends of morphology, treat them with 80 mg / L gibberellin or indoleacetic acid or indolebutyric acid, and leave them overnight; add clean water to a commercially available special substrate for vegetable seedling raising (main component: peat) and mix well until it is appropriate that when the substrate is grabbed into a ball and dropped on the ground, it naturally scatters, and then fill the mixed substrate into plastic flower pots or 72-hole seedling trays. Place the flower pots or seedling trays filled with the substrate in a tray about 5 cm deep.Take out the processed rubber grass root segments that have been left overnight. Insert the lower end of the root segments into the seedling-raising substrate according to the morphological upper and lower ends, with the upper end exposed about 0.5 cm above the substrate. Fill the tray in which the rubber grass root segments have been cuttaged with water. The substrate will absorb water from the tray to maintain appropriate humidity, which is beneficial for the rooting of rubber grass. After filling with water, a commercially available transparent film can be used to completely cover the flower pot or seedling tray. Make several evenly distributed holes in the film to facilitate ventilation, which can effectively ensure that the upper growth point of the root segments will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28°C to reduce the excessive evaporation of water caused by direct sunlight. Observe the germinated rubber grass tissue after cutting. According to the evaporation of water in the tray, appropriately irrigate the rubber grass before germination. Generally, it can be observed that the leaf bud primordium will differentiate in about 7 days after cutting the rubber grass root segments, new yellow and nearly transparent leaves will grow in about 13 days, and the leaves will turn green to form new leaves of rubber grass in about 16 days. Generally, more than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow continuously on the roots, and new rubber grass plants will gradually grow. When the new yellow and nearly transparent leaves grow, the irrigation should be reduced. If there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate to avoid the new rubber grass plants being infected with mold and rotting and dying due to too high humidity. Transplant the rapidly propagated rubber grass to the experimental field after about 45 days. The root system of the rubber grass plants at about 16 days has not developed completely. The soil humidity should be controlled at about 30%, and the temperature should be 25-28°C. Continue to grow for about 20 days, and then transfer to outdoor hardening off and wait for transplantation. When the rubber grass has grown for about 45 days and the root system has fully wrapped the seedling-raising substrate, take out the rubber grass seedlings together with the seedling-raising substrate and transplant them into the experimental plot. Cover with a sunshade net and water thoroughly. The rubber grass will survive after about 7 days of slow seedling, and the sunshade net can be removed. When the rubber grass is in bud, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different rubber grass materials. At 10 am - 12 pm every morning, when the rubber grass flower is fully open and the stigma is in a "Y" shape, manually assist in pollination. The seeds can be harvested about 12 days after flowering. Select materials by the above method, perform multi-generation asexual rapid propagation, and finally achieve the purification of rubber grass materials. Mix and freely mate the inbred lines with similar agronomic traits and relatively high rubber content to obtain a new high-quality rubber grass variety.

[0049] Example 3: A method for cultivating a new variety to break the self-incompatibility of rubber grass

[0050] Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of Taraxacum kok-saghyz Rodin with clean water, remove the leaves above the ground, completely peel off all the rotten outer root tissues, cut the roots of Taraxacum kok-saghyz Rodin with a diameter of more than 1 mm into root segments of 1-2 cm with a sharp blade, neatly arrange them in the Petri dish according to the upper and lower ends of morphology, treat them with 160 mg / L gibberellin or indoleacetic acid or indolebutyric acid, and let them stand overnight; add clean water to the commercially available special substrate for vegetable seedling raising (main component: peat) and mix well until it is appropriate that when the substrate is grabbed and kneaded into a ball and dropped on the ground, it naturally scatters, and then fill the plastic flower pot or 72-hole seedling tray with the mixed substrate. Place the flower pot or seedling tray filled with the substrate in a tray about 5 cm deep.Take out the processed rubber grass root segments that have been left overnight. Insert the lower end of the root segments into the seedling-raising substrate according to the morphological upper and lower ends, and expose the upper end about 0.5 cm above the substrate. Fill the trays in which the rubber grass root segments have been cuttaged with water. The substrate will absorb water from the trays to maintain appropriate humidity, which is beneficial for the rubber grass to take root. After filling with water, a commercially available transparent film can be used to completely cover the flower pots or seedling trays. Make several evenly distributed holes in the film to facilitate ventilation, which can effectively ensure that the growth points on the upper part of the root segments will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28 °C to reduce the excessive evaporation of water caused by direct sunlight. Observe the germinated rubber grass tissue after cutting. According to the evaporation of water in the trays, appropriately irrigate the rubber grass before germination. Observe that the rubber grass root segments generally differentiate into leaf bud primordia in about 7 days, grow yellow and nearly transparent new leaves in about 13 days, and the leaves turn green to form new leaves of the rubber grass in about 16 days. Generally, more than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow successively on the roots, and new rubber grass plants gradually grow. When the yellow and nearly transparent new leaves grow, the irrigation should be reduced. If there is still a large amount of water in the trays, it should be poured out in time to reduce the humidity in the substrate, so as to avoid the new rubber grass plants being infected with mold and rotting and dying due to too high humidity. Transplant the rapidly propagated rubber grass to the experimental field after about 45 days. The root systems of the rubber grass plants at about 16 days have not developed completely. The soil humidity should be controlled at about 30%, and the temperature should be 25-28 °C. Continue to grow for about 20 days, and then transfer to outdoor hardening until transplantation. When the roots of the rubber grass have fully wrapped the seedling-raising substrate after about 45 days of cultivation, take out the rubber grass seedlings together with the seedling-raising substrate and transplant them into the experimental plots. Cover with a sunshade net and water thoroughly. The rubber grass will survive after about 7 days of slow seedling, and the sunshade net can be removed. When the rubber grass is in bud, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different rubber grass materials. At 10:00 - 12:00 every morning, when the rubber grass flowers are fully open and the stigma is in a "Y" shape, manually assist in pollination. The seeds can be harvested about 12 days after flowering. Select materials by the above method, perform multi-generation asexual rapid propagation, and finally achieve the purification of rubber grass materials. Mix and freely mate the inbred lines with similar agronomic traits and high rubber content to obtain high-quality new rubber grass varieties.

[0051] Example 4: A method for cultivating a new variety to break the self-incompatibility of rubber grass

[0052] Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of Taraxacum kok-saghyz Rodin with clean water, remove the above-ground leaves, completely peel off the rotten outer root tissues, cut the Taraxacum kok-saghyz Rodin roots with a diameter of more than 1 mm into root segments of 1 - 2 cm with a sharp blade, neatly arrange them in the Petri dish according to the upper and lower ends of morphology, treat them with 240 mg / L gibberellin or indoleacetic acid or indolebutyric acid, and leave them overnight; add clean water to a commercially available special substrate for vegetable seedling raising (main component: peat) and mix well until it is appropriate that when grabbed, the substrate forms a ball and naturally scatters when dropped on the ground, and then fill the plastic flower pots or 72-cell seedling trays with the mixed substrate. Place the flower pots or seedling trays filled with the substrate in a tray about 5 cm deep.Take out the processed rubber grass root segments that have been left overnight. Insert the lower end of the root segments into the seedling-raising substrate according to the morphological upper and lower ends, and expose the upper end about 0.5 cm above the substrate. Fill the tray in which the rubber grass root segments have been cuttaged with water. The substrate will absorb water from the tray to maintain appropriate humidity, which is beneficial for the rooting of rubber grass. After filling with water, a commercially available transparent film can be used to completely cover the flower pot or seedling tray. Make several holes evenly on the film to facilitate ventilation, which can effectively ensure that the growth points on the upper part of the root segments will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28 °C to reduce the excessive evaporation of water caused by direct sunlight. Observe the germinated rubber grass tissue after cutting. According to the evaporation of water in the tray, appropriately irrigate the rubber grass before germination. Observe that the rubber grass root segments generally differentiate into leaf bud primordia in about 7 days, grow yellow and nearly transparent new leaves in about 13 days, and the leaves turn green to form new leaves of rubber grass in about 16 days. Generally, more than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow continuously on the roots, and new rubber grass plants gradually grow. When yellow and nearly transparent new leaves grow, the irrigation should be reduced. If there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate, so as to avoid the new rubber grass plants being infected with mold and rotting and dying due to too high humidity. Transplant the rapid-propagated rubber grass to the experimental field about 45 days later. The root system of the rubber grass plants about 16 days old has not developed completely. The soil humidity should be controlled at about 30%, and the temperature should be 25-28 °C. Continue to grow for about 20 days, and then transfer to outdoor hardening to wait for transplantation. When the rubber grass has formed buds, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different rubber grass materials. At 10:00-12:00 every morning, when the rubber grass flowers are fully open and the stigma is in a "Y" shape, manually assist in pollination. The seeds can be harvested about 12 days after flowering. Select materials and perform multi-generation asexual rapid propagation according to the above method, and finally achieve the purification of rubber grass materials. Mix and freely mate the inbred lines with similar agronomic traits and relatively high rubber content to obtain high-quality new rubber grass varieties.

[0053] Example 5: A method for cultivating a new variety to break the self-incompatibility of rubber grass

[0054] Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of Taraxacum kok-saghyz Rodin with clean water, remove the above-ground leaves, completely peel off the rotten outer root tissues, cut the Taraxacum kok-saghyz Rodin roots with a diameter of more than 1 mm into root segments of 1-2 cm with a sharp blade, neatly arrange them in the Petri dish according to the upper and lower ends of morphology, treat them with 160 mg / L gibberellin and 80 mg / L indolebutyric acid, and leave them overnight; add clean water to a commercially available special substrate for vegetable seedling raising (main component: peat) and mix well until it is appropriate that when the substrate is grabbed into a ball and dropped on the ground, it naturally scatters, and then fill the plastic flower pot or 72-hole seedling tray with the mixed substrate. Place the flower pot or seedling tray filled with the substrate in a tray about 5 cm deep.Take out the processed rubber grass root segments that have been left overnight. Insert the lower end of the root segments into the seedling-raising substrate according to the morphological upper and lower ends, and expose the upper end about 0.5 cm above the substrate. Fill the tray in which the rubber grass root segments have been cuttaged with water. The substrate will absorb water from the tray to maintain appropriate humidity, which is beneficial for the rooting of rubber grass. After filling with water, a commercially available transparent film can be used to completely cover the flower pot or seedling tray. Make several holes evenly on the film to facilitate ventilation, which can effectively ensure that the growth point on the upper part of the root segment will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28 °C to reduce the excessive evaporation of water caused by direct sunlight. Observe the germinated rubber grass tissue after cutting. According to the evaporation of water in the tray, appropriately irrigate before the rubber grass germinates. Observe that the rubber grass root segments generally differentiate into leaf bud primordia in about 7 days, grow yellow and nearly transparent new leaves in about 13 days, and the leaves turn green to form new leaves of rubber grass in about 16 days. Generally, more than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow continuously on the roots, and new rubber grass plants gradually grow. When the yellow and nearly transparent new leaves grow, the irrigation should be reduced. If there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate, so as to avoid the new rubber grass plants being infected with mold and rotting and dying due to too high humidity. Transplant the rapidly propagated rubber grass to the experimental field after about 45 days. The root system of the rubber grass plants at about 16 days has not developed completely. The soil humidity should be controlled at about 30%, and the temperature should be 25-28 °C. Continue to grow for about 20 days, and then transfer to outdoor hardening until transplantation. When the rubber grass has formed buds, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different rubber grass materials. Every morning from 10 o'clock to 12 o'clock, when the rubber grass flowers are fully open and the stigma is in a "Y" shape, manually assist in pollination. The seeds can be harvested about 12 days after flowering. Select materials by the above method, perform multi-generation asexual rapid propagation, and finally achieve the purification of rubber grass materials. Mix and freely mate the inbred lines with similar agronomic traits and relatively high rubber content to obtain high-quality new rubber grass varieties.

[0055] Example 6: A method for cultivating a new variety to break the self-incompatibility of rubber grass

[0056] Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of Taraxacum kok-saghyz Rodin with clean water, remove the above-ground leaves, completely peel off all the rotten outer root tissues, use a sharp blade to cut the roots of Taraxacum kok-saghyz Rodin with a diameter of more than 1 mm into root segments of 1-2 cm, neatly arrange them in the Petri dish according to the upper and lower ends of morphology, treat them with 160 mg / L gibberellin and 160 mg / L indolebutyric acid, and let them stand overnight; add clean water to the commercially available special substrate for vegetable seedling raising (main component: peat) and mix well until it is appropriate that when the substrate is grabbed into a ball and dropped on the ground, it will naturally disperse, and then fill the mixed substrate into plastic flower pots or 72-hole seedling trays. Place the flower pots or seedling trays filled with the substrate in a tray about 5 cm deep.Take out the processed rubber grass root segments that have been left overnight. Insert the lower end of the root segments into the seedling-raising substrate according to the morphological upper and lower ends, and expose the upper end about 0.5 cm above the substrate. Fill the tray in which the rubber grass root segments have been cuttaged with water. The substrate will absorb water from the tray to maintain appropriate humidity, which is conducive to the rooting of rubber grass. After filling with water, a commercially available transparent film can be used to completely cover the flower pot or seedling tray. Make several holes evenly on the film to facilitate ventilation, which can effectively ensure that the growth points on the upper part of the root segments will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28 °C to reduce the rapid evaporation of water caused by direct sunlight. Observe the germinated rubber grass tissue after cutting. According to the evaporation of water in the tray, appropriately irrigate before the rubber grass germinates. Observe that the rubber grass root segments generally differentiate into leaf bud primordia in about 7 days, grow yellow and nearly transparent new leaves in about 13 days, and the leaves turn green to form new leaves of rubber grass in about 16 days. Generally, more than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow continuously on the roots, and new rubber grass plants gradually grow. When the yellow and nearly transparent new leaves grow, the irrigation should be reduced. If there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate, so as to avoid the new rubber grass plants being infected by mold and rotting and dying due to too high humidity. Transplant the rapid-propagated rubber grass to the experimental field about 45 days later. The root system of the rubber grass plants about 16 days old has not developed completely. The soil humidity should be controlled at about 30%, and the temperature should be 25-28 °C. Continue to grow for about 20 days, and then transfer to outdoor hardening until transplantation. When the rubber grass has formed buds, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different rubber grass materials. Every morning from 10 o'clock to 12 o'clock, when the rubber grass flowers are fully open and the stigma is in a "Y" shape, manually assist in pollination. The seeds can be harvested about 12 days after flowering. Select materials by the above method, carry out multi-generation asexual rapid propagation, and finally achieve the purification of rubber grass materials. Mix and freely mate the inbred lines with similar agronomic traits and high rubber content to obtain high-quality new rubber grass varieties.

[0057] Example 7: A method for cultivating a new variety to break the self-incompatibility of rubber grass

[0058] Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of Taraxacum kok-saghyz Rodin with clean water, remove the above-ground leaves, completely peel off all the rotten outer root tissues, use a sharp blade to cut the roots of Taraxacum kok-saghyz Rodin with a diameter of more than 1 mm into root segments of 1-2 cm, neatly place them in the Petri dish according to the upper and lower ends of morphology, treat them with 160 mg / L gibberellin and 240 mg / L indolebutyric acid, and let them stand overnight; add clean water to the commercially available special substrate for vegetable seedling raising (main component: peat) and mix well until it is appropriate that when the substrate is grabbed and kneaded into a ball and dropped on the ground, it naturally scatters, and then fill the plastic flower pot or 72-hole seedling tray with the mixed substrate. Place the flower pot or seedling tray filled with the substrate in a tray about 5 cm deep.Take out the rubber grass root segments that have been processed overnight and insert the lower end into the seedling medium according to the morphological upper and lower ends, and the upper end is exposed to the medium about 0.5cm; fill the tray with water after the rubber grass root segments are cut, and the medium will absorb water from the tray to maintain the appropriate humidity of the medium, so as to facilitate the rooting of rubber grass; after filling with water, you can use a commercially available transparent film to completely cover the flower pot or seedling tray, and evenly punch a few holes on the film for ventilation, which can effectively ensure that the upper growth point of the root segment will not lose water too quickly and affect germination; under the condition of guaranteed humidity, the indoor temperature should be controlled at 25-2 8℃, reduce the rapid evaporation of water caused by direct sunlight; observe the germination of rubber grass tissue after cutting, and irrigate appropriately before the rubber grass germinates according to the evaporation of water in the tray; observe that the root segment of rubber grass will generally differentiate into leaf bud primordia in about 7 days, grow yellow nearly transparent new leaves in about 13 days, and the leaves will turn green to form new leaves of rubber grass in about 16 days; generally more than 80% of the root segments will grow new leaves within this time, and the roots will also grow new root hairs one after another, and new rubber grass plants will gradually grow; when yellow nearly transparent new leaves grow, irrigation should be reduced, such as tray If there is still a lot of water in the substrate, it should be poured out in time to reduce the humidity in the substrate to prevent the new rubber grass plants from being infected with mold and rotting and dying due to excessive humidity; transplant the fast-growing rubber grass to the test field after about 45 days; the root system of the rubber grass plants about 16 days old has not yet fully developed, so the soil humidity should be controlled at about 30%, the temperature should be 25-28℃, and they should continue to grow for about 20 days, then move them to outdoor seedling hardening and wait for transplanting; when the roots of the rubber grass have fully wrapped the seedling substrate after about 45 days of cultivation, take out the rubber grass seedlings together with the seedling substrate and transplant them to the test plot, cover them with water and put them in the test plot. Shade net, water thoroughly, rubber grass seedlings survive in about 7 days, and the shade net can be removed; when rubber grass buds, use insect-proof nets to make small arch sheds for isolation to prevent pollen from different materials of rubber grass. At 10 am to 12 pm every day, when the rubber grass flowers are fully open and the stigma is in a "Y" shape, artificial pollination is performed on the flowers. Seeds can be harvested about 12 days after flowering; the above method is used for material selection, multi-generation asexual rapid propagation, and ultimately the purification of rubber grass materials is achieved. The self-bred lines with similar agronomic traits and high rubber content are mixed and freely mated to obtain high-quality new varieties of rubber grass. See the attachment for details of related growth and experimental conditions. Figure 6 , Attachment Figure 7 , Attachment Figure 8 , Attachment Figure 9 .

[0059] Example 7: Comparison of the effects of different plant hormone treatments

[0060] Based on the above-mentioned Embodiments 1 to 6, the effects of different plant hormone treatments were compared.

[0061] 1 Materials and Methods

[0062] 1.1 Test materials

[0063] The material for the rubber grass root segments was the Duolun variety, and the sampling location was the Yili area of Xinjiang. The filter paper used was ordinary filter paper, and the diameter of the glass culture dish was 100 mm. The temperature in the artificial climate chamber was 28 °C, and the relative humidity was 60%.

[0064] 1.2 Test method

[0065] The test was conducted on the first floor of the Cotton Building of the Xinjiang Academy of Agricultural Sciences. The rubber grass roots were divided into upper, middle, and lower parts, and root segments 1.5 - 2 cm long were cut. The filter paper germination bed was moistened, and 20 rubber grass root segments were placed in each culture dish for the rooting and germination test. Each concentration was placed in three culture dishes for the upper, middle, and lower parts. In the culture dishes with single hormones, 1 ml of GA3, IAA, and IBA at 3 concentration gradients of 80 mg / L, 160 mg / L, and 240 mg / L and 4 ml of distilled water were added respectively. In the culture dishes with mixed hormones, 0.5 ml of GA3 at 80 mg / L and 160 mg / L was mixed with 0.5 ml of IBA and IAA at 80 mg / L, 160 mg / L, and 240 mg / L, and then 4 ml of distilled water was added to each. Then, it was placed in an artificial climate chamber at a temperature of 28 ± 0.5 °C and a relative humidity of 60% to observe the germination and rooting situation. 1 ml of distilled water was supplemented every day. The criterion for rooting was that new roots more than 2 mm long grew from the root segments, and the criterion for germination was that new leaves grew green from the root segments. The number of root segments with germination and rooting was counted daily until the number of root segments with germination and rooting no longer changed.

[0066] 1.3 Data statistics and processing

[0067] The calculation formula is as follows:

[0068] Germination rate (%) = total number of germinated root segments / total number of tested root segments × 100%;

[0069] Rooting rate (%) = total number of rooted root segments / total number of tested root segments × 100%.

[0070] 2 Results and analysis

[0071] 2.1 Effects of single hormones on germination and rooting of root segments at different parts

[0072] Three hormones, gibberellin, indoleacetic acid, and indolebutyric acid, were used to soak and treat the rubber grass root segments at different concentrations, with distilled water as the control. The germination and rooting situations of the rubber grass root segments were observed and recorded. The test results showed that the rubber grass root segments had a certain totipotency and could differentiate and grow new roots and new shoots under the treatment of hormones and distilled water immersion, and grow into a complete plant. See the appendix Figure 1, under the treatment of gibberellin, the germination potential and germination rate of rubber grass root segments were significantly higher at the concentration of 160 mg / L than those at other concentrations; under different concentration treatments, some roots of rubber grass root segments grew, without an obvious pattern. Under different concentration treatments, the rooting and germination rates of the lower root segments near the root cap end of rubber grass were significantly higher than those of the upper and middle root segments. The rooting and germination rate of the lower root segments treated with 160 mg / L gibberellin reached the highest, with a germination rate of 65% and a rooting rate of 20%. See appendix Figure 2 , under the treatment of indoleacetic acid, the germination rate of rubber grass root segments was significantly lower than that of gibberellin. The highest germination rate was that of the middle root segments of rubber grass treated at the concentration of 160 mg / L, reaching 35%. In terms of rooting, it was significantly better than the treatment with gibberellin. The highest rooting rate was that of the middle root segments of rubber grass treated at the concentration of 240 mg / L, reaching 50%; the rooting rate of the middle and lower root segments was significantly higher than that of the upper root segments, and there was no obvious pattern in the germination rates of root segments at different positions; there was no obvious difference in the rooting rate and germination rate. See appendix Figure 3 , under the treatment of indolebutyric acid, with different concentration treatments, the germination rates of rubber grass root segments were all significantly reduced, and the germination rates of most rubber grass root segments dropped to 0, while the rooting rate increased significantly, with the highest being 100%; among them, the rooting performance of rubber grass root segments treated at the concentration of 160 mg / L was relatively stable, and the rooting rates of the upper, middle, and lower root segments all reached more than 50%, with the highest rooting rate in the lower root segments. See appendix Figure 4 , under the control of distilled water treatment, the rooting and germination rates of the lower root segments were significantly higher than those of the middle and upper root segments, and there was no obvious difference in the rooting rate and germination rate. Generally speaking, under the treatments of indoleacetic acid and distilled water control, there was no obvious promoting or inhibiting effect on the rooting and germination of rubber grass root segments. Gibberellin can promote the germination of rubber grass root segments, and indolebutyric acid can promote the rooting of rubber grass root segments.

[0073] 2.1.2 Effects of mixed hormones on the germination and rooting of root segments at different positions

[0074] From the analysis results in 2.1.1, it can be seen that different hormones have different degrees of inhibitory and promoting effects on the rooting and germination of rubber grass root segments. Therefore, during the cultivation of rubber grass root segments, two hormones at different concentrations were added simultaneously to obtain the optimal hormone concentration ratio for the rooting and germination of rubber grass root segments. See appendix Figure 5, Root segments treated with the mixed hormones GA3+IAA and GA3+IBA can all produce new roots and buds, but there are obvious differences. The experimental treatments that failed to take root and germinate are individual cases. Root segments treated with GA3+IBA (160mg / L+80mg / L), GA3+IBA (160mg / L+240mg / L), GA3+IAA (80mg / L+80mg / L), and GA (80mg / L+160mg / L) all completely produced new roots and buds in the upper, middle, and lower parts. Among them, the root segments treated with GA3+IBA (160mg / L+240mg / L) took root and germinated more stably, and the rooting and germination rate was higher, significantly higher than that of the control distilled water treatment.

[0075] As described above, the present invention can be preferably implemented. The above embodiments are only descriptions of the preferred implementation modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various changes and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should fall within the protection scope determined by the present invention.

Claims

1. A method for cultivating a new variety that breaks the self-incompatibility of Taraxacum kok-saghyz, characterized in that, The described cultivation method is obtained by the following steps: (1) Take a Petri dish with a diameter of about 150 mm that has been cleaned, and place 1 dry filter paper of the same specification on the Petri dish. Select excellent Taraxacum kok-saghyz Rodin single plants that meet the breeding objectives, wash the soil on the roots of the Taraxacum kok-saghyz Rodin with clean water, remove the leaves above the ground, completely peel off all the rotten outer tissues of the roots, cut the Taraxacum kok-saghyz Rodin roots with a diameter of more than 1 mm into root segments of 1-2 cm, neatly arrange them in the Petri dish according to the upper and lower morphological ends, treat them with plant hormones, and let them stand overnight. (2) Add clean water to the special vegetable seedling-raising substrate on the market whose main component is peat moss and mix well. Grab the substrate and knead it into a ball, then let it fall to the ground and naturally disperse. Then, fill the mixed substrate into plastic flower pots or 72-hole seedling trays. Place the flower pots or seedling trays filled with the substrate in a tray about 5 cm deep. Take out the overnight-treated Taraxacum kok-saghyz Rodin root segments from step (1), and according to the upper and lower morphological ends, insert the lower ends into the seedling-raising substrate, with the upper ends exposed about 0.5 cm above the substrate. (3) Fill the tray in which the Taraxacum kok-saghyz Rodin root segments have been cut and inserted in step (2) with water. The substrate will absorb water from the tray to maintain an appropriate humidity, which is beneficial for the Taraxacum kok-saghyz Rodin to take root. After filling with water, completely cover the flower pot or seedling tray with a commercially available transparent film, and evenly punch several holes in the film to facilitate ventilation, effectively ensuring that the upper growth point of the root segment will not lose water too quickly and affect germination. Under the condition of ensuring humidity, the indoor temperature should be controlled at 25-28 °C to reduce the rapid evaporation of water caused by direct sunlight. (4) Observe the germinated Taraxacum kok-saghyz Rodin tissue after cutting in step (3), and appropriately irrigate according to the water evaporation in the tray before the Taraxacum kok-saghyz Rodin germinates. (5) Observe that the Taraxacum kok-saghyz Rodin root segments in step (4) will differentiate into leaf bud primordia in about 7 days, grow yellow and nearly transparent new leaves in about 13 days, and the leaves will turn green to form new leaves of the Taraxacum kok-saghyz Rodin in about 16 days. More than 80% of the root segments will grow new leaves within this time, and new root hairs will also grow continuously on the roots, and new Taraxacum kok-saghyz Rodin plants will gradually grow. When the yellow and nearly transparent new leaves grow, the irrigation should be reduced, and if there is still a large amount of water in the tray, it should be poured out in time to reduce the humidity in the substrate, so as to avoid the new plants of the Taraxacum kok-saghyz Rodin being infected with mold and rotting and dying due to too high humidity. (6) The root systems of the Taraxacum kok-saghyz Rodin plants about 16 days old are not fully developed. The soil humidity should be controlled at about 30%, and the temperature should be 25-28 °C. Continue to grow for about 20 days, and then transfer them to the outdoor for hardening off and wait for transplantation. (7) The roots of the Taraxacum kok-saghyz Rodin in step (6) have fully wrapped the seedling-raising substrate after about 45 days of cultivation. Take out the Taraxacum kok-saghyz Rodin seedlings together with the seedling-raising substrate, transplant them into the experimental plot, cover them with a sunshade net, and pour enough water. The Taraxacum kok-saghyz Rodin will survive after about 7 days of slow seedling growth, and then remove the sunshade net. (8) When the Taraxacum kok-saghyz Rodin is in the budding stage, use an insect-proof net to make a small arch shed for isolation to prevent cross-pollination between different materials of the Taraxacum kok-saghyz Rodin. Every day from 10:00 to 12:00 in the morning, when the flowers of the Taraxacum kok-saghyz Rodin are fully open and the stigmas are in a "Y" shape, manually assist in pollination. Harvest the seeds about 12 days after flowering. (9) Select materials by the methods described in the above steps (1) to (8), perform multi-generation asexual rapid propagation, and finally achieve the purification of Taraxacum kok-saghyz materials. Mix and freely mate inbred lines with similar agronomic traits and high rubber content to obtain high-quality new varieties of Taraxacum kok-saghyz; The plant hormone used is gibberellin at 160 mg / L and indolebutyric acid at 240 mg / L.

2. Application of a new variety cultivation method for breaking self-incompatibility of Taraxacum kok-saghyz as described in claim 1 in the cultivation of new varieties of Taraxacum kok-saghyz.

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