Method for inducing cane polyploid plant by using colchicine

Abstract

The invention belongs to the technical field of plant polyploid breeding, and particularly relates to a method for inducing a cane polyploid plant by utilizing colchicine. According to the method, 0.03-0.04% of colchicine solution is used for inducing germinated cane seeds for 48-72 h, colchicine can induce cane chromosome doubling, plants are made huge, meanwhile, the growth speed is increased, on one hand, the yield of cane rattan is increased, the cultivation cost is reduced, the economic benefit is greatly improved, on the other hand, the soft quality of cane rattan can be improved, and the yield of cane rattan is increased. The method is used for producing different types of rattan products, and high-value utilization and product development of the cane rattan are achieved. The result of the embodiment shows that the induction rate of the polyploidy plant of the cane cane is as high as 6.36%-12.73%. Furthermore, the gibberellin solution is used for accelerating germination of the alpine cane seeds and then germinating the alpine cane seeds, the germination period of the alpine cane seeds can be greatly shortened, the germination rate and germination potential of the alpine cane seeds are improved, and seedlings emerge neatly.

Description

Technical Field

[0001] This invention belongs to the field of plant polyploid breeding technology, specifically relating to a method for inducing polyploid plants of *Cephalotaxus fortunei* using colchicine. Background Technology

[0002] cane ( Calamus rhabdocladus Burret is a climbing vine belonging to the genus Burret in the family Arecaceae. It prefers warm and humid climates and is both shade-tolerant and cold-hardy. It grows mostly in dense forests or forest edges and is an important component of tropical rainforest ecosystems. Young Burret seedlings can be used medicinally to treat bruises and sprains. The vines produced are hard and are often combined with white vine to make furniture frames, walking sticks, and woven rattan products. They are lightweight and durable, making them an important vine resource.

[0003] Polyploid plants, due to chromosome doubling, exhibit a superposition effect, resulting in differences from ordinary diploid plants in various aspects such as morphology, nutrient content, cellular characteristics, and resistance. After polyploidization, multiple organs, including roots, stems, leaves, flowers, and fruits, may become larger, and growth vigor and stress resistance may be enhanced to some extent, increasing the plant's commercial value. Polyploidization holds promise for accelerating the growth rate of *Cephalotaxus fortunei*, increasing vine yield, and improving the texture of the vines, thereby cultivating *Cephalotaxus fortunei* germplasm for multiple uses.

[0004] Colchicine, as a mutagen, alters the number of chromosomes in germinating seeds or seedlings and is widely used in polyploid breeding of ornamental plants such as lilies, roses, orchids, and chrysanthemums. However, *Cynanchum paniculatum* is not an ornamental plant, and its polyploid breeding is relatively underdeveloped; therefore, cultivating polyploid *Cynanchum paniculatum* plants is particularly urgent in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a method for inducing polyploid plants of *Cymbidium goeringii*, to cultivate polyploid plants of *Cymbidium goeringii* with fast growth rate and excellent vine quality, and to increase vine yield.

[0006] This invention provides a method for inducing polyploid plants of *Cymbidium goeringii*, comprising the following steps: inducing germinating *Cymbidium goeringii* seeds to germinate for 48-72 hours using a 0.03-0.04% colchicine solution.

[0007] Preferably, the volume ratio of the colchicine solution to the germinated *Cymbidium goeringii* seeds is (2-3):1.

[0008] Preferably, the induction method includes immersion and agitation at a speed of 110-120 rpm.

[0009] Preferably, the hypocotyl length of the germinated *Cymbidium goeringii* seeds is 0.1-0.3 cm.

[0010] Preferably, the method for preparing the germinated *Cymbidium goeringii* seeds includes: treating the *Cymbidium goeringii* seeds with gibberellin solution to induce germination, thereby obtaining the germinated *Cymbidium goeringii* seeds.

[0011] Preferably, the concentration of the gibberellin solution is 200-1000 mg / L, and the volume ratio of the gibberellin solution to the seeds of *Cynanchum paniculatum* is (2-3):1.

[0012] Preferably, the germination treatment time is 48-72 hours; the germination treatment method is soaking and shaking at a speed of 110-120 rpm.

[0013] Preferably, the induction method further includes: after induction, sowing the induced *Cephalotaxus fortunei* seeds; after the seeds germinate and develop leaves, identifying the induced seedlings; the identification indicators include one or more of leaf shape, leaf length, leaf width, and leaf length-to-width ratio. Compared with the *Cephalotaxus fortunei* seedlings obtained by sowing seeds before induction, the induced seedlings are considered to have been successfully induced if they exhibit one or more of the following results: 1) The leaf shape is palmately lobed with a reduced number of leaflets; 2) The leaf length is significantly increased; 3) The leaf width is significantly increased; 4) The leaf length-to-width ratio is significantly increased.

[0014] This invention provides the application of *Cephalotaxus fortunei* seeds obtained by the induction method described above in the breeding of *Cephalotaxus fortunei* polyploid plants.

[0015] This invention provides a breeding method for polyploid plants, comprising the following steps: The seeds of *Cephalotaxus fortunei* were induced using the induction method described above. After obtaining polyploid *Cephalotaxus fortunei* seeds, they were sown and cultivated. At the end of the first growth period of *Cephalotaxus fortunei*, the plants were transplanted for field management.

[0016] Beneficial effects: This invention utilizes a 0.03-0.04% colchicine solution to induce germination of *Cephalotaxus fortunei* seeds for 48-72 hours. Colchicine induces chromosome doubling in *Cephalotaxus fortunei*, resulting in polyploid plants after cultivation. Chromosome doubling leads to larger plants and faster growth, increasing vine yield, reducing cultivation costs, and significantly improving economic benefits. Furthermore, it improves the softness of the vines, enabling diverse applications in the production of various vine products, thus achieving high-value utilization and product development of *Cephalotaxus fortunei*. Example results show that the induction rate of polyploid plants is as high as 6.36%-12.73%. Furthermore, this invention utilizes gibberellin solution to pre-germinate *Cephalotaxus fortunei* seeds, significantly shortening the germination cycle, increasing germination rate and vigor, and resulting in uniform seedling emergence. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly described below.

[0018] Figure 1 Actual images of the seeds of *Cymbidium goeringii* that have undergone germination and sprouting in Examples 1 (T1) and 2 (T2); Figure 2 This is a photograph of a polyploid plant of *Cymbidium candida*. Figure 3 This is a photograph of a diploid *Cymbidium goeringii*. Figure 4 The leaf length and width of the *Cynanchum paniculatum* plants in Examples 1 (T1) and 2 (T2) are in cm. Figure 5 The leaf length-to-width ratio of the *Cymbidium goeringii* plants in Examples 1 (T1) and 2 (T2) is shown. Detailed Implementation

[0019] This invention provides a method for inducing polyploid plants of *Cymbidium goeringii*, comprising the following steps: inducing germinating *Cymbidium goeringii* seeds to germinate for 48-72 hours using a 0.03-0.04% colchicine solution.

[0020] In one embodiment, the present invention uses gibberellin solution to treat *Cephalotaxus fortunei* seeds for germination, thereby obtaining germinated *Cephalotaxus fortunei* seeds. In one embodiment, the concentration of the gibberellin solution is 200-1000 mg / L; in another embodiment, the concentration is 300-900 mg / L; in another embodiment, the concentration is 400-800 mg / L; in another embodiment, the concentration is 500-700 mg / L; in another embodiment, the concentration is 600 mg / L. In one embodiment, the volume ratio of gibberellin solution to *Cephalotaxus fortunei* seeds is (2-3):1. In one embodiment, the germination treatment time is 48-72 hours; in another embodiment, the germination treatment time is 50-70 hours; in another embodiment, the germination treatment time is 55-65 hours; in another embodiment, the germination treatment time is 60 hours. As one implementation method, the germination treatment method described in this invention involves soaking and shaking at a speed of 110-120 rpm. Cane Vine seeds have dormancy characteristics and high water content; once dehydrated, the germination rate is significantly affected. Sand stratification generally requires more than 45 days for germination to begin, during which time the seeds need to be turned weekly to maintain moisture; however, germination is uneven, the entire germination cycle can last for 3 months or even longer, and the germination rate is low. This invention utilizes gibberellin solution to treat Cane Vine seeds for germination. Seeds treated with gibberellin can germinate after 23-25 ​​days, with a faster germination speed, shorter cycle, and a certain degree of improved germination rate. Seedlings emerge uniformly, further improving induction efficiency.

[0021] After obtaining the germinated Cane Vine seeds, this invention uses a 0.03-0.04% colchicine solution to induce the germination of the Cane Vine seeds for 48-72 hours.

[0022] In one embodiment, the volume ratio of colchicine solution to germinated *Cephalotaxus fortunei* seeds is (2-3):(1); in another embodiment, the volume ratio is 3:1. In one embodiment, the induction method includes soaking and shaking at 110-120 rpm. This invention utilizes colchicine to induce germination of *Cephalotaxus fortunei* seeds, resulting in larger plants and faster growth. This increases the yield of *Cephalotaxus fortunei* vines, reduces cultivation costs, and significantly improves economic benefits. Furthermore, it improves the soft quality of the vines. Limiting the induction time with colchicine solution in this invention increases the success rate. Induction time <48h results in extremely low polyploid induction rate, while induction time >72h is detrimental to subsequent seed germination.

[0023] In one embodiment, the hypocotyl length of the germinated *Cymbidium goeringii* seeds described in this invention is 0.1-0.3 cm; in another embodiment, the hypocotyl length of the germinated *Cymbidium goeringii* seeds described in this invention is 0.2 cm. Using *Cymbidium goeringii* seeds with a hypocotyl length of 0.1-0.3 cm as the induction target, this invention can induce chromosome doubling, improving the induction success rate compared to other induction materials, resulting in a reduced number of leaflets and an increase in leaflet length and / or width.

[0024] In one implementation method, after induction, the present invention sows the induced *Cephalotaxus fortunei* seeds. After the seeds germinate and develop leaves, the induced seedlings are identified. The identification indicators include one or more of leaf shape, leaf length, leaf width, and leaf length-to-width ratio. Compared with the *Cephalotaxus fortunei* seedlings obtained by sowing seeds before induction, the induced seedlings are considered to have been successfully induced if they exhibit one or more of the following results: 1) palmate, fully lobed leaves with a reduced number of leaflets; 2) significantly increased leaflet length; 3) significantly increased leaflet width; 4) significantly increased leaflet length-to-width ratio. In one implementation method, the reduction in the number of leaflets is defined as a reduction to 1-4 leaflets. In another implementation method, the significant increase in the leaflet length-to-width ratio is defined as an increase of at least 1.2 times in the leaflet length-to-width ratio.

[0025] This invention utilizes colchicine induction to successfully obtain high-quality polyploid plants of *Cephalotaxus fortunei*, with a success rate as high as 6.36%-12.73%. Furthermore, after chromosome doubling, the seedlings exhibit increased growth, with leaf length increasing by 4.33%-26.97% and leaf width increasing by 85.71%-122.86% compared to the control. The seedlings also show increased biomass and superior growth vigor.

[0026] This invention provides the application of *Cephalotaxus fortunei* seeds obtained by the induction method described above in the breeding of *Cephalotaxus fortunei* polyploid plants.

[0027] This invention provides a breeding method for polyploid plants, comprising the following steps: The seeds of *Cephalotaxus fortunei* were induced using the induction method described above. After obtaining polyploid *Cephalotaxus fortunei* seeds, they were sown and cultivated. At the end of the first growth period of *Cephalotaxus fortunei*, the plants were transplanted for field management.

[0028] In one embodiment, the culture substrate of the present invention comprises river sand, garden soil, and peat moss. In another embodiment, the volume ratio of river sand, garden soil, and peat moss in the present invention is (2-2.5):(2-3):1. The present invention does not impose strict requirements on the specific methods of sowing, cultivation, and field management; conventional methods in the field are sufficient.

[0029] To further illustrate the present invention, the following detailed description, in conjunction with the accompanying drawings and embodiments, provides a method for inducing polyploid plants of *Cephalotaxus fortunei* using colchicine, but these descriptions should not be construed as limiting the scope of protection of the present invention.

[0030] Example 1 Treatment and germination of *Cymbidium goeringii* seeds (1) Harvesting of the fruit of the cane vine: The mature fruit of the cane vine is harvested, brought back to the laboratory, and the pulp is removed by washing to obtain the seeds.

[0031] (2) Seed treatment and germination: Poorly developed seeds were removed by flotation, and then the seeds were taken out. Gibberellin (GA3) solutions with concentrations of 0, 200 g / L and 1000 g / L were prepared. The seeds of *Cynanchum paniculatum* were placed in a container containing gibberellin solution, with a seed volume to gibberellin solution volume ratio of 1:2. Finally, the container was placed on a shaker and shaken at a speed of 110 rpm for 72 hours to promote germination. After germination, the seeds were dried in a cool place to remove surface moisture, placed in a sealed bag, and sealed tightly. The seeds were then placed at room temperature to germinate. 100 seeds of *Cynanchum paniculatum* were used for each treatment, and the treatment was repeated 3 times. Germination rate, germination potential, average germination time, germination index, and germination duration were statistically analyzed according to the following methods. The results are shown in Table 1.

[0032] Germination rate calculation formula: GR=NgNt×100%; where GR is the germination rate, Ng is the number of seeds that germinated normally, and Nt is the total number of seeds tested; Germination potential calculation formula: GE=NeNt×100%, which reflects the uniformity and initial vigor of seed germination; where GE is the germination potential, Ne is the number of seeds that germinate normally in the early stage of germination (within the specified date), and Nt is the total number of seeds tested. Mean germination time is defined as the average number of days required for all tested seeds to germinate. The lower this value, the faster the germination rate. The calculation formula is: MGT = ∑(D×n)∑n; where MGT is the mean germination time, D is the number of days from the date of seedbed placement, n is the number of newly germinated seeds at the corresponding day D, and ∑ is the summation symbol.

[0033] Germination index calculation formula: GI=∑GtDt; where GI is the germination index, the higher the value, the stronger the germination vitality, Gt is the number of germinated on day t, and Dt is the corresponding number of germination days (calculated from the start of bed placement).

[0034] Germination duration: The number of days from the germination of the first seed to the germination of the last seed. A shorter time indicates higher uniformity. Calculation formula: GV=T 结束 -T 开始 T 开始 =Date of germination of the first seed, T 结束=The date on which the last seed germinated before it failed to germinate for several consecutive days.

[0035] Table 1. Effect of gibberellin concentration on seed germination of *Cynanchum paniculatum*

[0036] As shown in Table 1, the 200 g / L gibberellin solution has a better effect on promoting the germination of *Cynanchum paniculatum* seeds than the 1000 g / L gibberellin solution.

[0037] Example 2 Induction of polyploidy of *Cymbidium goeringii* (1) Harvesting of Cane Vine Fruit: In mid-May 2024, the mature Cane Vine fruits were harvested, brought back to the laboratory, and the pulp was removed by washing to obtain the seeds.

[0038] (2) Seed treatment and germination: Poorly developed seeds were removed using the flotation method, and then the seeds were taken out. A gibberellin (GA3) solution with a concentration of 200 g / L was prepared. 160 seeds of *Cephalotaxus fortunei* were selected and placed in a container containing gibberellin solution, with a seed volume to gibberellin solution volume ratio of 1:2. Finally, the container was placed on a shaker and shaken at a speed of 110 rpm for 72 hours to promote germination. After germination, the seeds were dried in a cool place to remove surface moisture, placed in a sealed bag, and sealed tightly. The seeds were then placed at room temperature to germinate. After 23 days at room temperature, the seeds began to germinate. After 60 days at room temperature, the germination rate reached 85%, and germination was basically completed. The actual picture of the germinated *Cephalotaxus fortunei* seeds is shown below. Figure 1 As shown in T1. Finally, select 100 seeds with a hypocotyl length of 0.1-0.3 cm for later use.

[0039] (3) Induction of polyploidy: Prepare a 0.30% colchicine solution, and then put seeds with a hypocotyl length of 0.1-0.3 cm into the colchicine solution. The volume ratio of the solution to the seed volume is 3:1. Finally, place the container on a shaker at 120 rpm and shake for 48 h.

[0040] (4) Seed sowing: After treatment, the seeds were removed and rinsed with running water for 10 minutes to remove any residual colchicine from the surface. They were then sown in a seedbed or cultivation container. A mixture of river sand, garden soil, and peat moss in a volume ratio of 2:2:1 was used as the substrate, approximately 20 cm thick, with a sowing depth of 1.5 cm. Simultaneously, 50 untreated seeds were sown as a control.

[0041] (5) Cultivation and management after sowing: 22 days after sowing, the cotyledons emerged one after another, and a total of 90 seedlings were obtained; 45 days later, the seedlings began to unfold their leaves. During the seedling growth period, keep the substrate moist and weed regularly.

[0042] (6) Polyploid identification: After seed germination and seedling leaf expansion, 7 polyploid plants were identified by measuring leaf shape changes, leaf length and width, with a polyploid induction rate of 6.36%. Schematic diagrams of polyploid and diploid *Cephalotaxus fortunei* are shown below. Figure 2 and Figure 3 As shown.

[0043] (7) Cultivation and management of polyploid plants: At the end of the first growing season, the plants that were initially identified as polyploid were transplanted to a new plot for separate cultivation and management. At the same time, the leaf shape, plant height, leaf length, leaf width and other trait indicators were observed to cultivate polyploid varieties of *Cephalotaxus fortunei*.

[0044] Example 3 Induction of polyploidy of *Cymbidium goeringii* (1) Harvesting of Cane Vine Fruit: In mid-May 2025, the mature Cane Vine fruits were harvested, brought back to the laboratory, and the pulp was removed by washing to obtain the seeds.

[0045] (2) Seed treatment and germination: Poorly developed seeds were removed using the flotation method, and then the seeds were taken out. A gibberellin (GA3) solution with a concentration of 1000 g / L was prepared. 200 seeds of *Cephalotaxus fortunei* were selected and placed in a container containing gibberellin solution, with a seed volume to gibberellin solution volume ratio of 1:3. Finally, the container was placed on a shaker and shaken at a speed of 120 rpm for 48 hours to promote germination. After germination, the seeds were dried in a cool place, placed in a sealed bag, and the bag was sealed tightly. The seeds were then placed at room temperature to germinate. The treated seeds began to germinate after 40 days, while the untreated seeds began to germinate after 45 days at room temperature. Germination was basically completed after 65 days at room temperature. The actual picture of the germinated *Cephalotaxus fortunei* seeds is shown below. Figure 1 As shown in T2. ​​Finally, select 100 seeds with a hypocotyl length of 0.1-0.3 cm for later use.

[0046] (3) Induction of polyploidy: Prepare a 0.40% colchicine solution, and then put seeds with a hypocotyl length of 0.1-0.3 cm into the colchicine solution. The volume ratio of the solution to the seed volume is 3:1. Finally, place the container on a shaker at 110 rpm and shake for 48 h.

[0047] (4) Seed sowing: After treatment, the seeds were removed and rinsed with running water for 15 minutes to remove any residual colchicine from the surface. They were then sown in a seedbed or cultivation container. A mixture of river sand, garden soil, and peat moss in a volume ratio of 2.5:3:1 was used as the substrate, approximately 25 cm thick, with a sowing depth of 2.0 cm. Simultaneously, 50 untreated seeds were sown as a control.

[0048] (5) Cultivation and management after sowing: 20 days after sowing, the cotyledons emerged one after another, and a total of 82 seedlings were obtained; 43 days later, the seedlings began to unfold their leaves. During the seedling growth period, keep the substrate moist and weed regularly.

[0049] (6) Polyploid identification: After the seedlings unfolded their leaves, 14 polyploid plants were identified by measuring changes in leaf shape, leaf length, and width. The polyploid induction rate was 12.73%. Schematic diagrams of polyploid and diploid *Cephalotaxus fortunei* are shown below. Figure 2 and Figure 3 As shown.

[0050] (7) Cultivation and management of polyploid plants: At the end of the first growing season, the plants that were initially identified as polyploid were transplanted to a new plot for separate cultivation and management. At the same time, the leaf shape, plant height, leaf length, leaf width and other trait indicators were observed to cultivate polyploid varieties of *Cephalotaxus fortunei*.

[0051] Test Example 1 Seeds of *Cynanchum paniculatum* were sown in 9cm diameter seedling pots. After 90 days of uniform cultivation and management, the leaf length, leaf width, and leaf length-to-width ratio of the *Cynanchum paniculatum* plants were measured. The results are shown in Tables 2-4. Figures 4-5 As shown.

[0052] Table 2. Leaf length (cm) of *Cynanchum paniculatum* plants

[0053] Note: CK represents uninduced diploid *Cephalotaxus fortunei* plants; T1 represents colchicine-induced polyploid *Cephalotaxus fortunei* plants from Example 2; and T2 represents colchicine-induced polyploid *Cephalotaxus fortunei* plants from Example 3. Leaflets 1-5 refer to the 1st to 5th leaflets. The same applies below.

[0054] Table 3. Leaf width (cm) of *Cynanchum paniculatum* plants

[0055] Table 4. Leaf length-to-width ratio of *Cynanchum paniculatum* plants

[0056] According to Tables 2-4 and Figures 4-5 It can be seen that after being soaked in colchicine, the number of leaflets in the seedlings of *Cephalotaxus fortunei* decreased, but the leaf length and width increased significantly. The leaf length increased by 4.33% to 26.97% compared with the control, and the leaf width increased by 85.71% to 122.86% compared with the control. The seedlings were more robust and had a greater growth advantage.

[0057] Comparative Example 1 Same as Example 1, except that the induction target in step (3) was changed to seeds with a hypocotyl length <0.1cm. The polyploid identification results showed that 14 polyploid plants were identified, with a polyploid induction rate of 12.73%.

[0058] Comparative Example 2 Same as Example 1, except that the induction target in step (3) was changed to seeds with a hypocotyl length > 0.3 cm. The polyploid identification results showed that 14 polyploid plants were identified, with a polyploid induction rate of 12.73%.

[0059] Comparative Example 3 Same as in Example 1, except that the induction target in step (3) is the seedling of *Cephalotaxus fortunei*.

[0060] Comparative Example 4 Same as Example 1, except that the concentration of colchicine solution in step (3) is 0.08%. The results of polyploid identification showed that one polyploid plant was identified, with a polyploid induction rate of 0.09%.

[0061] Comparative Example 5 Same as Example 1, except that the concentration of colchicine solution in step (3) is 0.02%. The results of polyploid identification showed that 0 polyploid plants were identified and the polyploid induction rate was 0.

[0062] Comparative Example 6 Same as Example 1, except that in step (2), the seeds were treated and germinated by sand storage, and seeds of *Cephalotaxus fortunei* with hypocotyl length of 0.1-0.3 cm after sand storage and germination were induced. A total of 100 seeds were treated with colchicine, and the polyploid identification results showed that 12 polyploid plants were obtained, with an induction rate of 12.0%.

[0063] Comparative Example 7 Same as Example 1, the only difference being that in step (3) induction, only soaking was performed without shaking. A total of 100 seeds were treated with colchicine, and the polyploid identification results showed that 10 polyploid plants were obtained, with an induction rate of 10.0%.

[0064] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for inducing polyploid plants of *Cymbidium goeringii*, characterized in that, The process includes the following steps: inducing the germination of *Cymbidium goeringii* seeds with a 0.03-0.04% colchicine solution for 48-72 hours.

2. The induction method according to claim 1, characterized in that, The volume ratio of the colchicine solution to the germinated *Cymbidium goeringii* seeds was (2-3):

1.

3. The induction method according to claim 1, characterized in that, The induction method includes immersion and oscillation at a speed of 110-120 rpm.

4. The induction method according to claim 1, characterized in that, The hypocotyl length of the germinated *Cymbidium goeringii* seeds is 0.1-0.3 cm.

5. The induction method according to claim 4, characterized in that, The method for preparing the germinated Cane Vine seeds includes: treating the Cane Vine seeds with gibberellin solution to induce germination, thereby obtaining the germinated Cane Vine seeds.

6. The induction method according to claim 5, characterized in that, The concentration of the gibberellin solution is 200-1000 mg / L, and the volume ratio of the gibberellin solution to the seeds of *Cynanchum paniculatum* is (2-3):

1.

7. The induction method according to claim 5, characterized in that, The germination treatment time is 48-72 hours; the germination treatment method is soaking and shaking at a speed of 110-120 rpm.

8. The induction method according to any one of claims 1-7, characterized in that, The induction method further includes: after induction, sowing the induced *Cephalotaxus fortunei* seeds; after the seeds germinate and develop leaves, identifying the induced seedlings; the identification indicators include one or more of leaf shape, leaf length, leaf width, and leaf length-to-width ratio. Compared with the *Cephalotaxus fortunei* seedlings obtained by sowing seeds before induction, the induced seedlings are considered to have been successfully induced if they exhibit one or more of the following results: 1) The leaf shape is palmately lobed with a reduced number of leaflets; 2) The leaflet length is significantly increased; 3) The leaflet width is significantly increased; 4) The leaflet length-to-width ratio is significantly increased.

9. The application of the seeds of *Cephalotaxus fortunei* obtained by the induction method according to any one of claims 1-8 in the breeding of polyploid *Cephalotaxus fortunei* plants.

10. A breeding method for a polyploid plant called *Cymbidium goeringii*, characterized in that, Includes the following steps: The seeds of *Cephalotaxus fortunei* were induced using the induction method described in any one of claims 1-8. After obtaining polyploid *Cephalotaxus fortunei* seeds, they were sown and cultivated. At the end of the first growth period of *Cephalotaxus fortunei*, the *Cephalotaxus fortunei* plants were transplanted for field management.

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