Method for planting leaf rust resistant daylily

Abstract

The invention relates to the technical field of hemerocallis citrina baroni planting, in particular to a planting method of leaf rust resistant hemerocallis citrina baroni. The invention provides a leaf rust resistant daylily planting method which comprises the following steps: seed treatment: soaking sterilized daylily seeds in a seed treatment agent, and placing the soaked daylily seeds at a constant temperature of 35-37 DEG C for 6-8 days to obtain germinated daylily seeds; seedling culture management: sowing the hemerocallis citrina baroni seeds subjected to germination acceleration in a seedling culture substrate, and culturing until seedlings emerge to obtain hemerocallis citrina baroni seedlings; seedling emergence and transplanting: transplanting daylily seedlings into the soil treated by the soil treatment agent. The planting method can improve leaf rust resistance of the daylily.

Description

Technical Field

[0001] The present invention relates to the technical field of daylily cultivation, and specifically relates to a cultivation method for rust-resistant daylilies. Background Art

[0002] As a vegetable with rich nutrition and unique taste, daylilies are widely popular in the market. However, during the cultivation process of daylilies, leaf rust has always been a problem that cannot be ignored. Leaf rust not only causes a significant decrease in the yield of daylilies, but also seriously affects their quality, bringing huge economic losses to growers.

[0003] At present, growers usually rely on chemical pesticides to control leaf rust in daylilies. However, the long-term use of chemical pesticides not only increases the cultivation cost, but may also cause potential harm to the environment and human health. In addition, with the increasing resistance of pathogens, the control effect of chemical pesticides is gradually weakening.

[0004] Therefore, providing a more environmentally friendly and effective cultivation method to improve the rust resistance of daylilies has broad application prospects and market value. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a cultivation method for rust-resistant daylilies, which not only improves the rust resistance of daylilies, but also reduces the use of chemical pesticides, lowers the cultivation cost, and at the same time protects the environment and human health.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a cultivation method for rust-resistant daylilies, and the cultivation method includes the following steps:

[0008] Seed treatment: After sterilizing daylily seeds, soak them in a seed treatment agent, and then place them under the condition of a temperature of 35 - 37°C and keep them at a constant temperature for 6 - 8 days to obtain germinated daylily seeds;

[0009] Seedling management: Sow the germinated daylily seeds in a seedling cultivation substrate for cultivation until emergence to obtain daylily seedlings;

[0010] Seedling transplantation: Transplant the daylily seedlings into the soil treated with a soil treatment agent.

[0011] Preferably, the seed treatment agent includes daylily extracellular vesicles, abscisic acid, and gibberellin.

[0012] Preferably, the seedling cultivation substrate includes daylily extracellular vesicles, peat soil, and perlite.

[0013] Preferably, the soil treatment agent comprises daylily extracellular vesicles, vermiculite powder and weathered coal.

[0014] Preferably, by weight, the seed treatment agent comprises 0.03 - 0.05 parts of daylily extracellular vesicles, 3 - 5 parts of abscisic acid and 2 - 6 parts of gibberellin.

[0015] Preferably, by weight, the seedling substrate comprises 2 - 4 parts of daylily extracellular vesicles, 32 - 60 parts of peat soil and 50 - 80 parts of perlite.

[0016] Preferably, by weight, the soil treatment agent comprises 1 - 3 parts of daylily extracellular vesicles, 26 - 40 parts of vermiculite powder and 21 - 30 parts of weathered coal.

[0017] In a second aspect, there is provided a daylily resistant to leaf rust, which is planted according to the planting method of the present invention.

[0018] It should be noted that leaf rust has seriously affected the yield of daylilies in various planting areas of our country and the economic income of farmers. Daylily leaf rust is caused by Puccinia hemerocallidis, which mainly damages the leaves and flower stalks. Initially, blister - like spots are produced on the leaves and flower stems; in the later stage, the diseased plants produce fewer flower stalks or no flower stalks at all. The flower stems turn reddish - brown, the flower buds wither and are easy to fall off, and in severe cases, all the leaves of the whole plant wither. The prevention and control of daylily leaf rust should adopt the measures of "prevention first, combined prevention and control". Before the occurrence of daylily leaf rust, corresponding preventive measures should be taken.

[0019] In a third aspect, there is provided the application of the planting method of the present invention in improving the leaf - rust resistance of daylilies.

[0020] In a fourth aspect, there is provided a combined planting system for daylilies resistant to leaf rust. The combined planting system comprises a seed treatment agent, a seedling substrate and a soil treatment agent. The seed treatment agent comprises daylily extracellular vesicles, abscisic acid and gibberellin; the seedling substrate comprises daylily extracellular vesicles, peat soil and perlite; and the soil treatment agent comprises daylily extracellular vesicles, vermiculite powder and weathered coal.

[0021] Plant extracellular vesicles are nanoscale vesicles secreted by plant cells, containing 90% of the active ingredients in plants. They are the essence of the concentration of plant active ingredients, have a phospholipid bilayer structure, and contain substances such as DNA, small RNA and proteins, and can carry these biomolecules to participate in processes such as inter - cellular communication, material exchange and signal transduction.

[0022] Daylily extracellular vesicles refer to a kind of membranous vesicles released from daylily plant cells into the extracellular environment, with diameters usually ranging from dozens of nanometers to hundreds of nanometers. These vesicles contain rich bioactive molecules, such as proteins, nucleic acids, lipids, etc., and can participate in processes such as inter - cellular communication, material exchange and signal transduction.

[0023] There are significant differences between plant extracellular vesicles and plant extracts in terms of source, composition, and function. In terms of source, plant extracellular vesicles are nano-sized vesicles released by plant cells under specific physiological or pathological conditions. These vesicles are secreted by cells through the endosome-exocytosis pathway and have a double-membrane structure. Plant extracts are substances obtained by physically or chemically extracting plants. In terms of composition, plant extracellular vesicles mainly contain bioactive molecules such as proteins, nucleic acids, and lipids, which play important roles in plant growth and development, stress adaptation, and interactions with other organisms. The composition of plant extracts is different from that of plant extracellular vesicles. In terms of function, plant extracellular vesicles participate in processes such as cell-to-cell communication, material exchange, and signal transduction. The efficacy of plant extracts may be unstable.

[0024] In the present invention, the preparation method of daylily extracellular vesicles is as follows:

[0025] Weigh 150 - 250 g of fresh daylilies and pour them into a crusher. Add 150 - 250 mL of sterilized PBS to it. After crushing and homogenizing, centrifuge at 3000 - 4000×g at 4°C for 10 - 20 min to remove larger residues; take the yellow transparent solution in the middle layer and centrifuge at 5000 - 6000×g at 4°C for 20 - 30 min; take the supernatant and ultracentrifuge at 80000 - 90000×g at 4°C for 20 - 30 min, then resuspend the precipitate with 1 - 3 mL of sterile PBS and ultracentrifuge again at 90000 - 110000×g at 4°C for 30 - 40 min; after centrifugation, resuspend the precipitate with 1 - 3 mL of sterile PBS to obtain daylily extracellular vesicles.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] Through a large number of experimental screenings, the present invention concludes that by jointly using the seed treatment agent of the present invention including daylily extracellular vesicles, abscisic acid, and gibberellin, the seedling-raising substrate including daylily extracellular vesicles, peat soil, and perlite, and the soil treatment agent including daylily extracellular vesicles, vermiculite powder, and weathered coal, this combined planting system can help improve the resistance of daylilies to leaf rust and also increase the yield and quality of daylilies. During the experimental screening process, the inventor of the present invention conducted a large number of experimental screenings. The inventor of the present invention tried to replace daylily extracellular vesicles, abscisic acid, gibberellin, peat soil, perlite, vermiculite powder, and weathered coal with other substances for experiments and found that the technical solutions after replacement were not obvious in improving the resistance of daylilies to leaf rust and the yield and quality of daylilies; the inventor of the present invention tried to replace daylily extracellular vesicles with daylily extracts and found that the technical solutions after replacement were also average in improving the resistance of daylilies to leaf rust and the yield and quality of daylilies.

[0028] The inventor speculates that: on the one hand, the exosomes of Hemerocallis citrina Baroni regulate the activities of abscisic acid and gibberellin, enabling the seeds to obtain stronger growth force and stress resistance during germination, thus laying a foundation for subsequent growth and resistance to leaf rust. On the other hand, in the substrate preparation, the exosomes of Hemerocallis citrina Baroni interact with peat soil and perlite to regulate the soil microenvironment, promote the growth and reproduction of beneficial microorganisms, enhance the soil's capacity, and provide more favorable conditions for the growth and resistance to leaf rust of Hemerocallis citrina Baroni. On the further hand, the exosomes of Hemerocallis citrina Baroni interact with vermiculite powder and weathered coal to further improve the soil environment and increase the soil fertility, thus providing better guarantee for the growth and resistance to leaf rust of Hemerocallis citrina Baroni.

[0029] In addition, the exosomes of Hemerocallis citrina Baroni play an important role in the planting method of Hemerocallis citrina Baroni. It may provide active ingredients (the exosomes of Hemerocallis citrina Baroni may contain some active substances that can stimulate the immune system of Hemerocallis citrina Baroni plants; after contacting with Hemerocallis citrina Baroni, these substances can trigger the disease-resistant signal transduction pathway in Hemerocallis citrina Baroni, and then activate a series of defense reactions, such as producing disease-resistant related proteins, synthesizing antibacterial substances, etc.; these defense reactions can effectively inhibit the colonization and spread of Puccinia hemerocallidis). It can also promote the nutrient absorption and growth of Hemerocallis citrina Baroni (the exosomes of Hemerocallis citrina Baroni may also contain some substances that can promote the nutrient absorption and growth of Hemerocallis citrina Baroni; by improving the root environment of Hemerocallis citrina Baroni plants and enhancing the root activity, the exosomes of Hemerocallis citrina Baroni help Hemerocallis citrina Baroni better absorb and utilize nutrients and water in the soil; this can not only enhance the ability of Hemerocallis citrina Baroni plants to resist leaf rust, but also improve the overall growth potential and yield of Hemerocallis citrina Baroni plants). Moreover, it has a physical barrier effect (the exosomes of Hemerocallis citrina Baroni form a protective layer on the surface of Hemerocallis citrina Baroni plants, which may have a certain physical barrier effect; this protective layer can block the direct contact and infection of Puccinia hemerocallidis spores, thus reducing the incidence of leaf rust disease). Detailed implementation manners

[0030] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] Embodiment 1

[0032] This embodiment provides a planting method for Hemerocallis citrina Baroni resistant to leaf rust. The planting method includes the following steps:

[0033] Seed treatment: Select healthy daylily plants that have been growing for 6 years. Leave 3 - 4 thick flower buds on each flower stalk during the early flowering stage without picking them, and let them bear fruit to obtain daylily seeds. Sterilize the daylily seeds. After sterilization, soak the daylily seeds in a seed treatment agent, and then place them under the condition of a temperature of 35 - 37°C and keep them at a constant temperature for 6 - 8 days to obtain germinated daylily seeds.

[0034] Seedling management: Sow the germinated daylily seeds in a seedling-raising substrate with a thickness of 5 - 6 cm and cultivate until emergence to obtain daylily seedlings. When the daylily seedlings grow to a certain height (such as 5 - 6 cm) and have well-developed roots, transplant them.

[0035] In the embodiment of the present invention, a thickness of 5 - 6 cm can provide better heat preservation and moisture retention performance, and at the same time promote root development; ensure that the seedling-raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0036] The cultivation conditions are as follows:

[0037] During the day (6:00 - 18:00), maintain the temperature at 25 - 28°C to promote the hardening and stress resistance of the seedlings; at night (18:01 - 5:59): keep the temperature at 18 - 20°C, which helps the seedlings maintain growth vitality at night and reduces energy consumption;

[0038] If the natural light is insufficient, plant growth lights can be used for supplementary lighting on cloudy days or during periods with weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0039] Starting from the 4th day after sowing, ventilate from 8:00 - 17:00 every day to better regulate the humidity and carbon dioxide concentration in the seedling-raising shed, and promote photosynthesis and gas exchange.

[0040] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0041] Seedling emergence and transplantation: Transplant the daylily seedlings into the soil treated with a soil treatment agent.

[0042] Select loose, fertile, and well-drained soil for transplantation;

[0043] Before transplantation, the soil should be deeply plowed and finely cultivated to improve the air permeability and water retention of the soil; and use a soil treatment agent to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiment of the present invention can ensure the friendliness of the soil environment and the safety of the growth of daylily seedlings;

[0044] During transplantation, carefully take out the seedlings from the seedling-raising substrate, try to keep the integrity of the roots, and avoid damage to improve the survival rate after transplantation.

[0045] Dig holes in the prepared soil. The depth and width of the holes should be slightly larger than the root system size of the seedlings. Place the seedlings into the holes, gently cover the roots with soil, and gently compact it to make the seedlings closely combine with the soil.

[0046] After transplantation, water should be applied in a timely manner to promote the close combination of the seedlings with the soil and the growth of the root system.

[0047] Within a certain period after transplantation, well-rotted farmyard manure or compound fertilizer can be applied in an appropriate amount to provide sufficient nutrient supply. As the seedlings grow, top dressing should be carried out in a timely manner according to their growth conditions and soil fertility status.

[0048] Carry out intertillage and weed control regularly to improve soil air permeability and reduce the impact of weeds on the growth of daylilies. When intertilling, avoid damaging the root system of daylilies.

[0049] According to parts by weight, the seed treatment agent includes 0.03 parts of daylily extracellular vesicles, 3 parts of abscisic acid, and 2 parts of gibberellin; the seedling-raising substrate includes 2 parts of daylily extracellular vesicles, 32 parts of peat soil, and 50 parts of perlite; the soil treatment agent includes 1 part of daylily extracellular vesicles, 26 parts of vermiculite powder, and 21 parts of weathered coal.

[0050] Example 2

[0051] This example provides a planting method for daylilies resistant to leaf rust. The planting method includes the following steps:

[0052] Seed treatment: Select healthy daylilies that have grown for 6 years. Leave 3-4 thick flower buds on each flower stalk during the early flowering period without picking them, and let them bear fruit to be used as daylily seeds. Sterilize the daylily seeds. After soaking the sterilized daylily seeds in the seed treatment agent, place them under the condition of a temperature of 35-37 °C and keep them at a constant temperature for 6-8 days to obtain germinated daylily seeds.

[0053] Seedling-raising management: Sow the germinated daylily seeds in a seedling-raising substrate with a thickness of 5-6 cm for cultivation until emergence to obtain daylily seedlings. When the daylily seedlings grow to a certain height (such as 5-6 cm) and have well-developed root systems, transplant them.

[0054] In the embodiment of the present invention, a thickness of 5-6 cm can provide better heat preservation and moisture retention performance, and at the same time promote root development; ensure that the seedling-raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0055] The cultivation conditions are:

[0056] Maintain the temperature at 25 - 28°C during the day (6:00 - 18:00) to promote the hardiness and stress resistance of the seedlings; at night (18:01 - 5:59): keep the temperature at 18 - 20°C, which helps the seedlings maintain their growth vitality at night and reduces energy consumption;

[0057] If the natural light is insufficient, plant growth lights can be used for supplementary lighting on cloudy days or during periods of weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0058] Starting from the 4th day after sowing, ventilate from 8:00 - 17:00 every day to better regulate the humidity and carbon dioxide concentration in the seedling-raising shed, and promote photosynthesis and gas exchange.

[0059] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0060] Seedling emergence and transplantation: Transplant the daylily seedlings into the soil treated with a soil treatment agent.

[0061] Select loose, fertile, and well-drained soil for transplantation;

[0062] Before transplantation, the soil should be deeply plowed and finely cultivated to improve the soil permeability and water retention; and a soil treatment agent should be used to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiments of the present invention can ensure the friendliness of the soil environment and the safety of the growth of daylily seedlings;

[0063] During transplantation, carefully remove the seedlings from the seedling-raising substrate, try to keep the integrity of the roots, and avoid damage to improve the survival rate after transplantation.

[0064] Dig holes in the prepared soil, the depth and width of the holes should be slightly larger than the size of the seedlings' roots; place the seedlings into the holes, gently cover the roots with soil, and gently compact to make the seedlings closely combine with the soil.

[0065] After transplantation, water in a timely manner to promote the close combination of the seedlings with the soil and the growth of the roots.

[0066] In a period of time after transplantation, an appropriate amount of decomposed farmyard manure or compound fertilizer can be applied to provide sufficient nutrient supply; as the seedlings grow, topdressing should be carried out in a timely manner according to their growth conditions and the soil fertility status.

[0067] Regularly carry out intertillage and weed control to improve the soil permeability and reduce the impact of weeds on the growth of daylilies. Avoid damaging the roots of daylilies during intertillage.

[0068] By weight parts, the seed treatment agent comprises 0.05 part of Hemerocallis citrina Baroni extracellular vesicles, 5 parts of abscisic acid and 6 parts of gibberellin; the seedling-raising substrate comprises 4 parts of Hemerocallis citrina Baroni extracellular vesicles, 60 parts of peat soil and 80 parts of perlite; the soil treatment agent comprises 3 parts of Hemerocallis citrina Baroni extracellular vesicles, 40 parts of vermiculite powder and 30 parts of weathered coal.

[0069] Example 3

[0070] This example provides a planting method for Hemerocallis citrina Baroni resistant to leaf rust. The planting method comprises the following steps:

[0071] Seed treatment: Select healthy Hemerocallis citrina Baroni plants that have grown for 6 years. Leave 3-4 thick flower buds on each flower stalk during the early flowering stage without picking them, and let them bear fruit to obtain Hemerocallis citrina Baroni seeds; sterilize the Hemerocallis citrina Baroni seeds; soak the sterilized Hemerocallis citrina Baroni seeds in the seed treatment agent, and then place them under the condition of a temperature of 35-37 °C and keep them at a constant temperature for 6-8 days to obtain germinated Hemerocallis citrina Baroni seeds;

[0072] Seedling management: Sow the germinated Hemerocallis citrina Baroni seeds in a seedling-raising substrate with a thickness of 5-6 cm for cultivation until emergence to obtain Hemerocallis citrina Baroni seedlings; when the Hemerocallis citrina Baroni seedlings grow to a certain height (for example, 5-6 cm) and have well-developed roots, transplant them.

[0073] In the embodiment of the present invention, a thickness of 5-6 cm can provide better heat preservation and moisture retention performance, and at the same time promote root development; ensure that the seedling-raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0074] The cultivation conditions are as follows:

[0075] During the day (6:00-18:00), maintain the temperature at 25-28 °C to promote the hardening and stress resistance of the seedlings; at night (18:01-5:59): keep the temperature at 18-20 °C, which helps the seedlings maintain growth vitality at night and reduce energy consumption;

[0076] If the natural light is insufficient, a plant growth lamp can be used for supplementary lighting on cloudy days or during periods with weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0077] Starting from the 4th day after sowing, ventilate from 8:00 to 17:00 every day to better regulate the humidity and carbon dioxide concentration in the seedling-raising shed and promote photosynthesis and gas exchange.

[0078] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0079] Seedling emergence and transplantation: Transplant the Hemerocallis citrina Baroni seedlings into the soil treated with the soil treatment agent.

[0080] Select loose, fertile, well-drained soil for transplantation;

[0081] Before transplantation, the soil should be deeply plowed and finely cultivated to improve soil air permeability and water retention; and a soil treatment agent should be used to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiments of the present invention can ensure the friendliness of the soil environment and the safety of the growth of daylily seedlings;

[0082] During transplantation, the seedlings should be carefully taken out of the seedling-raising substrate, and the integrity of the roots should be maintained as much as possible to avoid damage, so as to improve the survival rate after transplantation.

[0083] Dig holes in the prepared soil. The depth and width of the holes should be slightly larger than the size of the roots of the seedlings; put the seedlings into the holes, gently cover the roots with soil, and gently compact them to make the seedlings closely combine with the soil.

[0084] After transplantation, water should be applied in time to promote the close combination of the seedlings with the soil and the growth of the roots.

[0085] Within a period of time after transplantation, decomposed farmyard manure or compound fertilizer can be applied in an appropriate amount to provide sufficient nutrient supply; as the seedlings grow, topdressing should be carried out in a timely manner according to their growth conditions and soil fertility status.

[0086] Regularly carry out intertillage and weed control to improve soil air permeability and reduce the impact of weeds on the growth of daylilies. During intertillage, the roots of daylilies should be avoided from being damaged.

[0087] By weight, the seed treatment agent includes 0.05 parts of daylily extracellular vesicles, 4 parts of abscisic acid and 3 parts of gibberellin; the seedling-raising substrate includes 3 parts of daylily extracellular vesicles, 50 parts of peat soil and 60 parts of perlite; the soil treatment agent includes 2 parts of daylily extracellular vesicles, 30 parts of vermiculite powder and 26 parts of weathered coal.

[0088] Comparative Example 1

[0089] This comparative example provides a method for planting daylilies resistant to leaf rust. The planting method includes the following steps:

[0090] Seed treatment: Select daylilies that have been growing healthily for 6 years. Leave 3-4 thick flower buds on each flower scape during the early flowering period without picking them, and let them bear fruit to be used as daylily seeds; sterilize the daylily seeds; after soaking the sterilized daylily seeds in the seed treatment agent, place them under the condition of a temperature of 35-37 °C and keep them at a constant temperature for 6-8 days to obtain germinated daylily seeds;

[0091] Seedling raising management: Sow the germinated Hemerocallis citrina Baroni seeds in a seedling raising substrate with a thickness of 5 - 6 cm for cultivation until emergence to obtain Hemerocallis citrina Baroni seedlings; when the Hemerocallis citrina Baroni seedlings grow to a certain height (e.g., 5 - 6 cm) and have well-developed roots, transplant them.

[0092] In the embodiment of the present invention, a thickness of 5 - 6 cm can provide better heat preservation and moisture retention performance, while promoting root development; ensure that the seedling raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0093] The cultivation conditions are as follows:

[0094] During the day (6:00 - 18:00), maintain the temperature at 25 - 28 °C to promote the hardening and stress resistance enhancement of the seedlings; at night (18:01 - 5:59): keep the temperature at 18 - 20 °C, which helps the seedlings maintain growth vitality at night and reduces energy consumption;

[0095] If the natural light is insufficient, plant growth lights can be used for supplementary lighting on cloudy days or during periods with weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0096] Starting from the 4th day after sowing, ventilation is carried out every day from 8:00 to 17:00 to better regulate the humidity and carbon dioxide concentration in the seedling raising shed, and promote photosynthesis and gas exchange.

[0097] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0098] Seedling emergence and transplantation: Transplant the Hemerocallis citrina Baroni seedlings into the soil treated with a soil treatment agent.

[0099] Select loose, fertile, and well-drained soil for transplantation;

[0100] Before transplantation, the soil should be deeply plowed and finely cultivated to improve the air permeability and water retention of the soil; and use a soil treatment agent to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiment of the present invention can ensure the environmental friendliness of the soil and the safety of the growth of Hemerocallis citrina Baroni seedlings;

[0101] During transplantation, carefully take out the seedlings from the seedling raising substrate, try to keep the integrity of the roots, and avoid damage to improve the survival rate after transplantation.

[0102] Dig holes in the prepared soil, the depth and width of the holes should be slightly larger than the size of the roots of the seedlings; put the seedlings into the holes, gently cover the roots with soil, and gently compact to make the seedlings closely combine with the soil.

[0103] After transplantation, water should be applied in a timely manner to promote the close combination of the seedlings with the soil and the growth of the roots.

[0104] In the period after transplantation, an appropriate amount of well-rotted farmyard manure or compound fertilizer can be applied to provide sufficient nutrient supply; as the seedlings grow, topdressing should be carried out in a timely manner according to their growth conditions and soil fertility status.

[0105] Carry out intertillage and weed control regularly to improve soil air permeability and reduce the impact of weeds on the growth of daylilies. When intertilling, the roots of daylilies should be avoided from being damaged.

[0106] By weight, the seed treatment agent includes 4 parts of abscisic acid and 3 parts of gibberellin; the seedling-raising substrate includes 3 parts of daylily extracellular vesicles, 50 parts of peat soil and 60 parts of perlite; the soil treatment agent includes 2 parts of daylily extracellular vesicles, 30 parts of vermiculite powder and 26 parts of weathered coal.

[0107] Comparative Example 2

[0108] This comparative example provides a planting method for daylilies resistant to leaf rust, and the planting method includes the following steps:

[0109] Seed treatment: Select healthy daylilies that have grown for 6 years. Leave 3-4 thick flower buds on each flower stalk during the early flowering period without picking them, and let them bear fruit to be used as daylily seeds; sterilize the daylily seeds; after soaking the sterilized daylily seeds in the seed treatment agent, place them under the condition of a temperature of 35-37 °C and keep them at a constant temperature for 6-8 days to obtain the germinated daylily seeds;

[0110] Seedling management: Sow the germinated daylily seeds in a seedling-raising substrate with a thickness of 5-6 cm for cultivation until emergence to obtain daylily seedlings; when the daylily seedlings grow to a certain height (for example, 5-6 cm) and have well-developed roots, transplant them.

[0111] In the embodiments of the present invention, a thickness of 5-6 cm can provide better heat preservation and moisture retention performance, and at the same time promote root development; ensure that the seedling-raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0112] The cultivation conditions are:

[0113] During the day (6:00-18:00), maintain the temperature at 25-28 °C to promote the hardening and stress resistance of the seedlings; at night (18:01-5:59): keep the temperature at 18-20 °C, which helps the seedlings maintain growth vitality at night and reduce energy consumption;

[0114] If the natural light is insufficient, plant growth lights can be used for supplementary lighting on cloudy days or during periods with weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0115] Starting from the 4th day after sowing, ventilation is carried out from 8:00 to 17:00 every day to better regulate the humidity and carbon dioxide concentration in the seedling-raising shed, and promote photosynthesis and gas exchange.

[0116] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0117] Seedling emergence and transplantation: Transplant the daylily seedlings into the soil treated with the soil treatment agent.

[0118] Select loose, fertile, and well-drained soil for transplantation;

[0119] Before transplantation, the soil should be deeply plowed and harrowed to improve the soil permeability and water retention; and the soil treatment agent should be used to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiment of the present invention can ensure the friendliness of the soil environment and the safety of the growth of daylily seedlings;

[0120] During transplantation, the seedlings should be carefully taken out of the seedling-raising substrate, and the integrity of the roots should be maintained as much as possible to avoid damage, so as to improve the survival rate after transplantation.

[0121] Dig holes in the prepared soil, and the depth and width of the holes should be slightly larger than the size of the roots of the seedlings; put the seedlings into the holes, gently cover the roots with soil, and gently compact them to make the seedlings closely combined with the soil.

[0122] After transplantation, water should be applied in time to promote the close combination of the seedlings with the soil and the growth of the roots.

[0123] In a period of time after transplantation, decomposed farmyard manure or compound fertilizer can be applied in an appropriate amount to provide sufficient nutrient supply; as the seedlings grow, top dressing should be carried out in a timely manner according to their growth conditions and soil fertility status.

[0124] Regularly carry out intertillage and weed control to improve the soil permeability and reduce the impact of weeds on the growth of daylilies. During intertillage, the roots of daylilies should be avoided from being damaged.

[0125] By weight, the seed treatment agent includes 0.05 parts of daylily extracellular vesicles, 4 parts of abscisic acid, and 3 parts of gibberellin; the seedling-raising substrate includes 50 parts of peat soil and 60 parts of perlite; the soil treatment agent includes 2 parts of daylily extracellular vesicles, 30 parts of vermiculite powder, and 26 parts of weathered coal.

[0126] Comparative Example 3

[0127] This comparative example provides a method for planting rust-resistant daylilies, and the planting method includes the following steps:

[0128] Seed treatment: Select daylily plants that have been growing healthily for 6 years. Leave 3 - 4 thick flower buds on each flower stalk during the early flowering stage without picking them, and let them bear fruit to obtain daylily seeds; sterilize the daylily seeds; soak the sterilized daylily seeds in a seed treatment agent, and then place them under the condition of a temperature of 35 - 37°C and keep them at a constant temperature for 6 - 8 days to obtain germinated daylily seeds;

[0129] Seedling management: Sow the germinated daylily seeds in a seedling-raising substrate with a thickness of 5 - 6 cm for cultivation until emergence to obtain daylily seedlings; when the daylily seedlings grow to a certain height (e.g., 5 - 6 cm) and have well-developed roots, transplant them.

[0130] In the embodiments of the present invention, a thickness of 5 - 6 cm can provide better heat preservation and moisture retention performance, and at the same time promote root development; ensure that the seedling-raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0131] The cultivation conditions are as follows:

[0132] During the day (6:00 - 18:00), maintain the temperature at 25 - 28°C to promote the hardening and stress resistance of the seedlings; at night (18:01 - 5:59): keep the temperature at 18 - 20°C, which helps the seedlings maintain growth vitality at night and reduces energy consumption;

[0133] If the natural light is insufficient, plant growth lights can be used for supplementary lighting on cloudy days or during periods with weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0134] Starting from the 4th day after sowing, ventilation is carried out from 8:00 to 17:00 every day to better regulate the humidity and carbon dioxide concentration in the seedling-raising shed, and promote photosynthesis and gas exchange.

[0135] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0136] Seedling emergence and transplantation: Transplant the daylily seedlings into the soil treated with a soil treatment agent.

[0137] Select loose, fertile, and well-drained soil for transplantation;

[0138] Before transplantation, the soil should be deeply plowed and finely cultivated to improve the air permeability and water retention of the soil; and use a soil treatment agent to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiments of the present invention can ensure the environmental friendliness of the soil and the safety of the growth of daylily seedlings;

[0139] During transplantation, carefully take out the seedlings from the seedling-raising substrate, try to keep the integrity of the roots, and avoid damage to improve the survival rate after transplantation.

[0140] Dig holes in the prepared soil. The depth and width of the holes should be slightly larger than the root system size of the seedlings; place the seedlings into the holes, gently cover the roots with soil, and gently compact it to make the seedlings closely combine with the soil.

[0141] After transplantation, water should be applied in a timely manner to promote the close combination of the seedlings with the soil and the growth of the root system.

[0142] Within a period of time after transplantation, decomposed farmyard manure or compound fertilizer can be applied in an appropriate amount to provide sufficient nutrient supply; as the seedlings grow, topdressing should be carried out in a timely manner according to their growth conditions and soil fertility status.

[0143] Carry out intertillage and weed control regularly to improve soil air permeability and reduce the impact of weeds on the growth of daylilies. When intertilling, avoid damaging the root system of daylilies.

[0144] By weight parts, the seed treatment agent comprises 0.05 part of daylily extracellular vesicles, 4 parts of abscisic acid and 3 parts of gibberellin; the seedling-raising substrate comprises 3 parts of daylily extracellular vesicles, 50 parts of peat soil and 60 parts of perlite; the soil treatment agent comprises 30 parts of vermiculite powder and 26 parts of weathered coal.

[0145] Comparative Example 4

[0146] This comparative example provides a planting method for daylilies resistant to leaf rust. The planting method comprises the following steps:

[0147] Seed treatment: Select healthy-growing daylilies that have been planted for 6 years. Leave 3-4 thick flower buds on each flower stalk during the early flowering period without picking, and let them bear fruit to be used as daylily seeds; sterilize the daylily seeds; after soaking the sterilized daylily seeds in the seed treatment agent, place them under the condition of a temperature of 35-37 °C and keep them at a constant temperature for 6-8 days to obtain the germinated daylily seeds.

[0148] Seedling management: Sow the germinated daylily seeds in a seedling-raising substrate with a thickness of 5-6 cm for cultivation until emergence to obtain daylily seedlings; when the daylily seedlings grow to a certain height (such as 5-6 cm) and have well-developed root systems, carry out transplantation.

[0149] In the embodiments of the present invention, a thickness of 5-6 cm can provide better heat preservation and moisture retention performance, and at the same time promote root development; ensure that the seedling-raising substrate has good drainage to avoid seed rot caused by excessive moisture.

[0150] The culture conditions are:

[0151] Maintain the temperature at 25 - 28°C during the day (6:00 - 18:00) to promote the hardening and stress resistance enhancement of the seedlings; at night (18:01 - 5:59): keep the temperature at 18 - 20°C, which helps the seedlings maintain growth vitality at night and reduces energy consumption;

[0152] If the natural light is insufficient, plant growth lights can be used for supplementary lighting on cloudy days or during periods with weak light to ensure that the seedlings obtain sufficient energy for photosynthesis.

[0153] Starting from the 4th day after sowing, ventilate from 8:00 - 17:00 every day to better regulate the humidity and carbon dioxide concentration in the seedling-raising shed, and promote photosynthesis and gas exchange.

[0154] Adjust the watering frequency and amount according to the weather conditions and the dryness of the substrate to maintain an appropriate humidity.

[0155] Seedling emergence and transplantation: Transplant the daylily seedlings into the soil treated with a soil treatment agent.

[0156] Select loose, fertile, and well-drained soil for transplantation;

[0157] Before transplantation, the soil should be deeply plowed and finely cultivated to improve soil air permeability and water retention; and a soil treatment agent should be used to disinfect and treat the soil to reduce the occurrence of pests and diseases; the soil treatment agent selected in the embodiments of the present invention can ensure the friendliness to the soil environment and the safety for the growth of daylily seedlings;

[0158] During transplantation, carefully take out the seedlings from the seedling-raising substrate, try to keep the integrity of the roots, and avoid damage to improve the survival rate after transplantation.

[0159] Dig holes in the prepared soil, the depth and width of the holes should be slightly larger than the size of the seedling roots; put the seedlings into the holes, gently cover the roots with soil, and gently compact to make the seedlings closely combine with the soil.

[0160] After transplantation, water in a timely manner to promote the close combination of the seedlings with the soil and the growth of the roots.

[0161] In a period after transplantation, decomposed farmyard manure or compound fertilizer can be applied in an appropriate amount to provide sufficient nutrient supply; as the seedlings grow, topdressing should be carried out in a timely manner according to their growth conditions and soil fertility status.

[0162] Regularly carry out intertillage and weed control to improve soil air permeability and reduce the impact of weeds on the growth of daylilies. Avoid damaging the roots of daylilies during intertillage.

[0163] By weight parts, the seed treatment agent comprises 0.05 part of daylily extract, 4 parts of abscisic acid and 3 parts of gibberellin; the seedling-raising substrate comprises 3 parts of daylily extracellular vesicles, 50 parts of peat soil and 60 parts of perlite; the soil treatment agent comprises 2 parts of daylily extracellular vesicles, 30 parts of vermiculite powder and 26 parts of weathered coal.

[0164] The preparation method of the daylily extract is as follows: Soak the daylily in ethanol and stir to dissolve the target components in ethanol to obtain the daylily extract.

[0165] Effect verification

[0166] Test method: The test site is a daylily planting base in Wennan Town, Xintai City, Shandong Province; the test daylily variety is April Flower; the test has seven treatments including Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4. The fertilizer and water management is good. The plot test method is adopted. The area of each test plot is 8 m 2 , 20 plants are planted in each plot, the plant spacing is 30 cm×40 cm, the large row spacing is 1 m, and they are arranged in a randomized block design; when the seedling height is 30 - 45 cm, the stem diameter is 0.6 - 0.8 cm, and the number of leaves is 15 - 20, record the incidence degree of daylily leaf rust, and calculate the average value of the incidence rate of each leaf on the plant as the incidence rate of each plant.

[0167] Carry out the identification of the resistance level of daylily according to the grading standard shown in Table 1, and the experimental results are shown in Table 2.

[0168] Table 1 Daylily leaf rust grading standard

[0169]

[0170] Table 2 Incidence rate of leaf rust of daylily plants

[0171] Treatment group Incidence rate Disease grade Example 1 The incidence of disease in the whole plant is less than 5% Medium resistance Example 2 The incidence of whole-plant disease is < 5% Medium resistance Example 3 No disease in the whole plant: 0% High resistance Control example 1 Disease in the whole plant ≥ 40% High susceptibility (HS) Control example 2 Disease in the whole plant ≥ 40% High susceptibility (HS) Control example 3 Disease in the whole plant ≥ 35% High susceptibility (HS) Control example 4 Disease in the whole plant ≥ 30% High susceptibility (HS)

[0172] As can be seen from Table 2, the incidence rate of leaf rust of daylily plants using the planting method of the leaf rust-resistant daylily of the present invention is 0 - 5%; among them, the daylily plants using the planting method of the leaf rust-resistant daylily in Example 3 have extremely high resistance to leaf rust disease, and the disease hardly occurs on them. While the daylily plants obtained without using the planting method of the leaf rust-resistant daylily of the present invention have extremely poor resistance to leaf rust disease, the disease is extremely likely to occur and develop rapidly on them, and usually has a serious impact on the yield or quality, and is not suitable for the planting of leaf rust-resistant daylily.

[0173] It can be seen from the effect verification test that the combined use of the seed treatment agent of the present invention including daylily extracellular vesicles, abscisic acid and gibberellin, the seedling-raising substrate including daylily extracellular vesicles, peat soil and perlite, and the soil treatment agent including daylily extracellular vesicles, vermiculite powder and weathered coal. This combined planting system can help improve the resistance of daylily to leaf rust, and can also improve the yield and quality of daylily. During the experimental screening process, the inventor conducted a large number of experimental screenings. The inventor tried to replace daylily extracellular vesicles, abscisic acid, gibberellin, peat soil, perlite, vermiculite powder and weathered coal with other substances for experiments, and found that the technical solutions after replacement were not obvious in improving the resistance of daylily to leaf rust and the yield and quality of daylily; the inventor tried to replace cherry extracellular vesicles with cherry extracts, and found that the technical solutions after replacement were also average in improving the resistance of daylily to leaf rust and the yield and quality of daylily.

[0174] This is because: on the one hand, daylily extracellular vesicles regulate the activities of abscisic acid and gibberellin, enabling the seeds to obtain stronger growth force and stress resistance during germination, thus laying a foundation for subsequent growth and resistance to leaf rust. On the other hand, in the substrate preparation, daylily extracellular vesicles interact with peat soil and perlite to regulate the soil microenvironment, promote the growth and reproduction of beneficial microorganisms, enhance the soil's ability, and provide more favorable conditions for the growth and resistance to leaf rust of daylily. On the one hand again, daylily extracellular vesicles interact with vermiculite powder and weathered coal to further improve the soil environment and increase the soil fertility, thereby providing better guarantee for the growth and resistance to leaf rust of daylily.

[0175] In addition, daylily extracellular vesicles play an important role in the daylily planting method. It may provide active ingredients (daylily extracellular vesicles may contain some active substances that can stimulate the immune system of daylily plants; after contacting with daylily, these substances can trigger the disease-resistant signal transduction pathway in daylily, and then activate a series of defense reactions, such as generating disease-resistant related proteins, synthesizing antibacterial substances, etc.; these defense reactions can effectively inhibit the colonization and spread of Puccinia hemerocaldis). It promotes the nutrient absorption and growth of daylily (daylily extracellular vesicles may also contain some substances that can promote the nutrient absorption and growth of daylily; by improving the root environment of daylily plants and enhancing root vitality, daylily extracellular vesicles help daylily better absorb and utilize nutrients and water in the soil; this can not only enhance the resistance of daylily plants to leaf rust, but also improve the overall growth potential and yield of daylily plants). It has a physical barrier effect (daylily extracellular vesicles form a protective layer on the surface of daylily plants, which may have a certain physical barrier effect; this protective layer can block the direct contact and infection of Puccinia hemerocaldis spores, thereby reducing the incidence of leaf rust disease).

[0176] The above-described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by relevant deductions and substitutions made by those of ordinary skill in the art under the conditions of the concept of the present invention without creative efforts fall within the scope of protection of the present invention.

Claims

1. A method for planting leaf rust-resistant daylily, characterized in that: The planting method comprises the following steps: Seed treatment: After the sterilized daylily seeds are soaked in a seed treatment agent, they are placed at a temperature of 35-37°C for 6-8 days to obtain germinated daylily seeds; Seedling management: sowing the germinated daylily seeds in a seedling medium for cultivation until they emerge to obtain daylily seedlings; Seedling transplantation: Transplant the daylily seedlings into the soil treated with soil treatment agent.

2. The planting method according to claim 1, characterized in that: The seed treatment agent comprises daylily exovesicles, abscisic acid and gibberellins.

3. The planting method according to claim 1, characterized in that: The seedling raising matrix comprises daylily outer vesicles, peat soil and perlite.

4. The planting method according to claim 1, characterized in that: The soil treatment agent comprises daylily exocysts, vermiculite powder and weathered coal.

5. The planting method according to claim 1, characterized in that: In terms of weight, the seed treatment agent includes 0.03-0.05 parts of daylily exovesicles, 3-5 parts of abscisic acid and 2-6 parts of gibberellins.

6. The planting method according to claim 1, characterized in that: In terms of weight, the seedling culture medium includes 2-4 parts of daylily exovesicles, 32-60 parts of peat soil and 50-80 parts of perlite.

7. The planting method according to claim 1, characterized in that: In terms of weight, the soil treatment agent includes 1-3 parts of daylily exovesicles, 26-40 parts of vermiculite powder and 21-30 parts of weathered coal.

8. A leaf rust-resistant daylily, characterized in that: Planting is carried out according to the planting method according to any one of claims 1 to 7.

9. Use of the planting method according to any one of claims 1 to 7 in improving the resistance of daylily to leaf rust.

10. A combined planting system for leaf rust-resistant daylily, characterized in that: The combined planting system comprises a seed treatment agent, a seedling matrix and a soil treatment agent, wherein the seed treatment agent comprises daylily exovesicles, abscisic acid and gibberellin; the seedling matrix comprises daylily exovesicles, peat soil and perlite; and the soil treatment agent comprises daylily exovesicles, vermiculite powder and weathered coal.

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