A method for vegetative propagation by dividing live plants of non viviparous tropical water lilies

Abstract

The present invention provides a method for vegetative propagation of non viviparous tropical water lilies by dividing the living plants. From August to September every year, the selected non viviparous tropical water lilies are evenly divided into 2 - 4 pieces starting from the roots. Each divided plant ensures that it contains at least one healthy leaf bud point and several mature leaves. Then, after division, they are planted in a submerged potted manner, with one divided plant planted in each pot, keeping the leaf bud point level with the soil surface of the planting. In the early stage, the water level above the leaf bud point is maintained at 5 - 10 cm, and the water level is gradually increased by 15 - 40 cm in the later stage. After vegetative propagation by dividing the living plants according to the present invention, the non viviparous tropical water lily plants can quickly resume growth and can grow and bloom normally 1 - 2 months later. The divided plants retain the flower color and traits of the original plants, having high economic value and ornamental value. And the divided non viviparous tropical water lilies can be divided and propagated again under permitted environmental conditions, further improving the propagation rate and reducing the cost of seedling breeding.

Description

Technical Field

[0001] The present invention belongs to the technical field of seedling breeding in ornamental horticulture, and relates to a method for vegetative propagation of non-viviparous tropical water lilies by dividing living plants. Background Art

[0002] Water lilies are the general name of plants in the genus Nymphaea L. of the family Nymphaeaceae, and are perennial aquatic herbaceous flowers. According to ecological characteristics, they can be divided into hardy water lilies and tropical water lilies. Tropical water lilies have straight and tall flowers that rise above the water surface, with a strong and fragrant aroma. They are excellent fresh cut flower materials. The flowers can be used to make tea, and the petioles and flower stalks are edible, having extremely high ornamental tourism and water scenery landscaping values.

[0003] Tropical water lilies are significantly superior to hardy water lilies in terms of flower color, leaf color, flowering ability, and uses. However, the prices of their seedlings are generally high, often hundreds or even thousands of yuan, seriously hindering the home gardening consumption of tropical water lilies. The main reason for the high price of tropical water lily seedlings is the difficulty in seedling breeding: (1) Most tropical water lilies cannot be propagated by seeds. Although the number of seeds in a single fruit of most tropical water lilies is huge, except for a very few original species that can be propagated by seeds, most of the currently cultivated varieties are hybrid first-generation or second-generation selected varieties, with serious and unstable trait segregation in the offspring and unable to be propagated by seeds; (2) Most tropical water lilies do not have the viviparous function. Some tropical water lilies have the reproductive function of viviparity in their mature leaves, that is, new complete plants grow from their leaf umbilici (i.e., the slightly concave or smooth nasal structure where the leaf and petiole meet). However, the number of tropical water lily varieties with the viviparous function is limited, and most of their flowers are single-petaled or semi-double-petaled, with relatively single flower colors and leaf colors; (3) The tissue culture and rapid propagation technology of water lilies is not yet mature, and there are no reports on the large-scale tissue culture and rapid propagation technology or related achievements of water lilies; (4) The rhizomes of rhizomatous plants such as Hedychium coronarium and Lilium can grow new lateral buds, which can be regarded as a complete individual and can develop into complete plants. Therefore, directly dividing and planting the rhizomes with lateral buds can be done; while tropical water lilies have only one main tuber, and no additional lateral buds can be formed around the tuber. Using the usual rhizome division method for tropical water lilies will lead to a significant increase in the mortality rate of the divided tropical water lilies.

[0004] However, a large number of excellent nonviviparous tropical water lilies with bright and colorful flowers, highly double-petaled or variegated flowers, and the Australian water lilies that have been very popular in recent years do not have the viviparous function, and the number of plants propagated is extremely slow. For the above-mentioned nonviviparous tropical water lilies that cannot be viviparously propagated, the commonly used method at present is to force them to form "dormant bulbs" through low temperature, and to preserve and propagate them in the form of bulbs formed after dormancy. That is, nonviviparous tropical water lilies usually form irregular spherical bulbs under low temperature conditions. When the temperature warms up and the water temperature rises in the coming year, the dormant bulbs germinate. Usually, 1 dormant bulb produces 1 bud point, and a few varieties can produce several bud points. After the bud points grow into leaves, they can be planted in the soil. The most suitable growth temperature for nonviviparous tropical water lilies is 30°C to 35°C. Therefore, the biggest drawback of propagating through the formation of dormant bulbs is that the temperature and low-temperature treatment time required for each variety of nonviviparous tropical water lilies to form dormant bulbs are different and are not easy to control. If the temperature is too high or too low, it is extremely easy to cause the necrosis of dormant bulbs, the success rate is low, and some nonviviparous tropical water lilies are directly frozen to death at low temperature and do not form dormant bulbs.

[0005] Therefore, there is an urgent need for a method for propagating nonviviparous tropical water lilies that is easy to operate, has a high survival rate, retains the traits of the original plant, and does not require the formation of dormant bulbs to accelerate the propagation speed of nonviviparous tropical water lilies, improve the quality of propagated plants, and reduce the price of seedlings. Summary of the Invention

[0006] In order to solve the above problems, the present invention provides a method for vegetative propagation of nonviviparous tropical water lilies by live division, which realizes the rapid propagation of nonviviparous tropical water lilies and solves the problems existing in the prior art.

[0007] The technical solution adopted by the present invention is a method for vegetative propagation of nonviviparous tropical water lilies by live division, including the following steps:

[0008] Step S1, the time for live division of nonviviparous tropical water lilies: from August to September every year, when the temperature is stable at 30°C, live division is carried out;

[0009] Step S2, selection and treatment of nonviviparous tropical water lilies: select nonviviparous tropical water lily varieties with strong growth, lush flower leaves, strong growth potential, and a crown width reaching a certain standard; dig out the selected nonviviparous tropical water lilies and wash them with clean water for treatment;

[0010] Step S3, disinfection and live division of nonviviparous tropical water lilies: sterilize the whole plant of nonviviparous tropical water lilies treated in Step S2, and then use a sharp knife to evenly divide the whole plant of nonviviparous tropical water lilies into 2 to 4 pieces starting from the root. During the division process, avoid damaging the small leaves and leaf bud points. Each divided plant ensures that it contains at least 1 healthy leaf bud point and several mature leaves to obtain the divided plants of nonviviparous tropical water lilies;

[0011] Step S4, Selection and treatment of planting soil: Select garden soil or pond soil rich in humus and with good structure as the planting soil. After fully drying in the sun, crush it and filter out obvious gravel and debris;

[0012] Step S5, Selection of planting site: The requirements for site selection are an open area with a drainage device, a water depth maintained at 50 cm to 70 cm, still water or a slow water flow rate, no obstruction around, sufficient sunlight, and a wind force below level 4;

[0013] Step S6, Planting: In the planting site selected in Step S5, adopt the method of potted submerged planting. Fill the potted plant with the planting soil from Step S4. When it is 80% full, add water to make it into a thin mud shape; then plant the divided non - viviparous tropical water lily obtained in Step S3 in the center of the pot, plant 1 divided plant in each pot, keep the leaf bud point level with the planting soil surface, maintain the water level 5 cm to 10 cm higher than the leaf bud point in the early stage, and gradually increase the water level by 15 cm to 40 cm in the later stage.

[0014] Step S7, Daily maintenance and management: Regularly remove old leaves and yellow leaves, and change the water in time if the water quality turns black or stinks.

[0015] Furthermore, in Step S1, the average temperature is not lower than 28 °C for at least 1 month after viviparous division.

[0016] Furthermore, in Step S2, the crown width reaches a certain standard, specifically: for large - sized varieties, the crown width is at least 1.5 m × 1.5 m; for medium - sized varieties, the crown width is at least 0.8 m × 0.8 m; for small - sized varieties, it is at least 0.4 m × 0.4 m.

[0017] Furthermore, in Step S2, the flushing treatment is specifically: Remove visible duckweed, spirogyra, snails and mud on the non - viviparous tropical water lily with the naked eye, and remove the old leaves, rotten leaves and diseased leaves on the non - viviparous tropical water lily, and protect the young leaves, tender leaves and bud points of the non - viviparous tropical water lily from being damaged during the treatment process.

[0018] Furthermore, in Step S3, the sterilization treatment is specifically: Soak in a 800 - to 1000 - fold solution of 50% carbendazim wettable powder for 1 h to 1.5 h, or spray with a 1000 - fold solution of 70% thiophanate - methyl wettable powder and then cover with a film for 24 h for sterilization treatment.

[0019] Furthermore, in Step S3, sharp tools need to be disinfected in advance.

[0020] Furthermore, in Step S4, the pH value of the planting soil is 5.6 to 7.5.

[0021] Furthermore, in Step S6, the water level maintained 10 cm higher than the leaf bud point in the early stage.

[0022] The beneficial effects of the present invention are:

[0023] (1) The method for vegetative propagation by dividing live plants of non viviparous tropical water lilies of the present invention does not require low temperature treatment to form dormant bulbs. Vegetative division of live plants can be carried out when they are growing most vigorously. The operation is simple and time-consuming is short, which improves work efficiency. Since low temperature treatment is not required, the survival rate is greatly improved.

[0024] (2) When additional lateral buds cannot be formed around the tubers of non viviparous tropical water lilies of the present invention, the roots are equally divided into 2 - 4 pieces according to the growth condition. Each plant ensures that it contains at least one healthy leaf bud point and several mature leaves, realizing vegetative division of live plants, overcoming the technical prejudice that each divided tuber of tuberous plants must have at least one lateral bud, and greatly improving the propagation rate of non viviparous tropical water lilies.

[0025] (3) After vegetative division of live plants of the present invention, the plants of non viviparous tropical water lilies resume growth rapidly and can grow and bloom normally 1 - 2 months later. And due to the mode of asexual reproduction, the plants after division retain the flower color and traits of the original plants, having high economic value and ornamental value; moreover, after the divided non viviparous tropical water lilies resume growth and bloom, when they grow strong, vegetative division can be carried out again under the condition that environmental conditions permit, further improving the propagation rate and reducing the cost of seedling breeding.

[0026] (4) The method for vegetative propagation by dividing live plants of the present invention is also applicable to viviparous tropical water lilies. Detailed implementation mode

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all 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.

[0028] 1. Time for vegetative division of live plants: To ensure the survival rate of vegetative division of live plants of non viviparous tropical water lilies, vegetative division of live plants needs to be carried out during the period when non viviparous tropical water lilies are growing most vigorously, generally in the midsummer season from August to September every year (in South China, it can be in July), when the temperature is stable at 30 °C for vegetative division of live plants. And to ensure that the non viviparous tropical water lilies after vegetative division of live plants can resume growth as soon as possible under a sufficiently suitable temperature, the average temperature is not lower than 28 °C for at least 1 month after division.

[0029] If the living ramets occur in the north, when the temperature drops below 15°C, transplant the non viviparous tropical water lilies of the ramets into a greenhouse. Ensure that the temperature in the greenhouse is not lower than 15°C and there is sufficient light, so that they can successfully survive the cold winter in the north. If placed outdoors, they will freeze to death. When the temperature rises above 15°C in the coming spring, move the non viviparous tropical water lilies of the ramets out of the greenhouse, and they can germinate, grow and bloom smoothly.

[0030] 2. Selection and treatment of non viviparous tropical water lilies:

[0031] Select non viviparous tropical water lily varieties with strong growth, lush leaves and flowers, strong growth potential and a crown width reaching a certain standard. For large varieties, the crown width generally reaches 1.5m×1.5m; for medium varieties, the crown width generally reaches 0.8m×0.8m; for small varieties, it generally reaches 0.4m×0.4m to be able to ramet.

[0032] Dig out the selected non viviparous tropical water lilies, rinse them with clean water to remove visible duckweed, spirogyra, snails and soil on the plants, and remove the old leaves, rotten leaves and diseased leaves on the plants. Pay attention to protecting the young leaves, tender leaves and bud points of the plants during the treatment process.

[0033] 3. Disinfection and living ramet of non viviparous tropical water lilies: Immerse the whole plant of the non viviparous tropical water lily treated in step 2 in a 800 - 1000 - fold solution of 50% carbendazim wettable powder for 1 - 1.5 hours, or spray with a 1000 - fold solution of 70% thiophanate methyl wettable powder and cover with a film for 24 - hour disinfection treatment. After disinfection treatment, use a sharp knife (pre - disinfected), and equally divide the non viviparous tropical water lily into 2 - 4 pieces according to the growth situation starting from the root. Avoid damaging the small leaves and leaf bud points during the division process, and ensure that each plant contains at least one healthy leaf bud point and several mature leaves.

[0034] In the method for living ramet propagation of non viviparous tropical water lilies of the present invention, in the case where no additional lateral buds can be formed around the tubers of non viviparous tropical water lilies, the roots are equally divided into 2 - 4 pieces according to the growth situation, and each plant is ensured to contain at least one healthy leaf bud point and several mature leaves, realizing living ramet, overcoming the technical prejudice that each ramet of tuberous plants must have at least one lateral bud on the tuber, and greatly improving the propagation rate of non viviparous tropical water lilies.

[0035] 50% carbendazim wettable powder is one of the main formulations of carbendazim. 50% represents the content of the active ingredient. 50% carbendazim wettable powder is a commercial pesticide formulation that can be bought on the market, and its ingredients and preparation methods have certain commercial standards. It is sufficient that the 50% carbendazim wettable powder used in the present invention can be bought on the market.

[0036] The 70% thiophanate-methyl wettable powder is one of the main formulations of thiophanate-methyl. The 70% represents the content of the active ingredient. The 70% carbendazim wettable powder is a commercial pesticide formulation that can be purchased on the market. Its composition and preparation method have certain commercial standards. The 70% thiophanate-methyl wettable powder used in this invention can be purchased on the market.

[0037] 4. Selection and treatment of planting soil: The planting soil is required to have a pH value of 5.6 - 7.5. Select garden soil or pond soil rich in humus and with good structure. After fully drying in the sun, crush it and filter out obvious gravel and debris to prevent the soil from hardening and affecting the planting of non-viviparous tropical water lilies and the growth of their roots.

[0038] 5. Selection of planting site: Water lilies like light and heat. The selected site is preferably an open area with a drainage device, where the water depth can be maintained at 50 cm - 70 cm, with still water or slow water flow, no obstruction around, sufficient sunlight, and wind force below level 4.

[0039] 6. Planting: Generally, the potted submerged planting method is adopted (which is convenient for controlling the water level). Select a planting pot of appropriate size according to different varieties of non-viviparous tropical water lilies. After filling the planting pot with planting soil to 80% full, add water to make it into a thin mud state. Plant the divided non-viviparous tropical water lily in the center of the pot, with 1 plant in each pot, and keep the leaf bud point level with the planting soil surface. In the early stage, the water level above the leaf bud point is maintained at 5 cm - 10 cm, and then the water level is gradually increased by 15 cm - 40 cm according to the characteristics and growth status of different varieties. Generally, after 1 - 2 months of planting, the divided non-viviparous tropical water lily will gradually resume growth and flowering.

[0040] The reason for filling the planting pot with planting soil to 80% full is as follows: Within a certain range, the thicker the soil layer, the more beneficial it is for the roots of non-viviparous tropical water lilies to stretch and absorb various nutrients required for growth. However, if the planting pot is completely filled with too much soil, when the planting pot is immersed in water, it is very easy for the soil in the pot to scatter into the water, polluting the water body. In addition, during the growth peak period of non-viviparous tropical water lilies, fertilizers need to be continuously topdressed. The newspaper or tea bag containing fertilizers needs to be sifted into the soil layer about 15 cm deep. If the soil layer is too full, it is also easy for the soil in the pot to overflow and pollute the water body.

[0041] Non-viviparous tropical water lilies have a long growth period and can bloom continuously throughout the year under suitable conditions, consuming a huge amount of nutrients. To ensure that the non-viviparous tropical water lilies that are forcibly divided live have better nutrients to recover quickly, generally 1 plant is planted in one planting bucket. In addition, non-viviparous tropical water lilies like light and heat. Planting multiple plants in the same pot may cause the leaves to cover each other, affecting photosynthesis.

[0042] All non viviparous tropical water lilies have "pineapple-shaped tubers". During their growth process, the pineapple-shaped tubers gradually grow upwards. Therefore, when planting, place them in the center of the planting pot with the tuber facing upwards and the bud point level with the soil layer. In the early stage, the water level 5 cm - 10 cm higher than the leaf bud point is mainly to enable the water temperature to rise rapidly, allowing the divided and transplanted non viviparous tropical water lilies to recover growth quickly and improve their survival rate. If the water layer is too low, the water temperature may rise sharply in midsummer, and the non viviparous tropical water lilies may be scorched by heat and die from heatstroke. Generally, it is best to keep the water layer 10 cm higher than the leaf bud point in the early stage. In the later stage, as the non viviparous tropical water lilies recover growth and the petioles gradually stretch, the water level is gradually increased according to different variety characteristics (such as large, medium or small, etc.) to allow them to grow under the most suitable water depth conditions. "Increase the water level by 15 cm - 40 cm". Generally, exceeding this range of the water level will not affect their survival, but it will affect flowering. For some varieties, if the water level rises rapidly and submerges the plants for a period of time (such as 10 days), they will die.

[0043] 7. Daily maintenance and management: Non viviparous tropical water lilies planted in garden soil or pond soil rich in humus and with good structure do not need to be fertilized. Excessive fertilizer will instead burn the roots of non viviparous tropical water lilies. Regularly remove old and yellow leaves to promote the germination of new leaves. If the water quality turns black or emits an odor, change the water in a timely manner.

[0044] The Flower Research Institute of Guangxi Academy of Agricultural Sciences preserves more than 100 varieties of tropical water lilies, covering different types of non viviparous tropical water lily varieties such as small, small and medium, medium and large, large, and giant. Since 2017, the non viviparous tropical water lilies have been bred using the non viviparous tropical water lily in vivo division propagation method of the present invention, and the breeding situation is shown in Table 1.

[0045] Table 1 List of breeding situations of non viviparous tropical water lilies using the in vivo division propagation method of the present invention

[0046]

[0047] As can be seen from Table 1, the survival rate of the plants using the non viviparous tropical water lily in vivo division propagation method of the present invention is relatively high, achieving a relatively high propagation rate, reducing the breeding difficulty and cost. Moreover, this breeding method is not restricted by breeding conditions such as geographical location, and can maximize the preservation of the flower color traits of non tropical water lilies, which is conducive to promoting the rapid development of the field of non viviparous tropical water lilies.

[0048] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for vegetative propagation by dividing living plants of non viviparous tropical water lilies, characterized in that, it includes the following steps: Step S1, time for dividing living plants of non viviparous tropical water lilies: From August to September every year, when the temperature is stable at 30 °C, divide the living plants, and the average temperature is not lower than 28 °C for at least 1 month after the division; Step S2, selection and treatment of non viviparous tropical water lilies: Select non viviparous tropical water lily varieties with strong growth, lush flowers and leaves, strong growth potential, and a crown width reaching a certain standard. Dig out the selected non viviparous tropical water lilies and rinse them with clean water. For large varieties, the crown width should be at least 1.5m×1.5m, for medium varieties, the crown width should be at least 0.8m×0.8m, and for small varieties, it should be at least 0.4m×0.4m; Step S3, disinfection and division of living plants of non viviparous tropical water lilies: Sterilize the whole plant of non viviparous tropical water lilies treated in Step S2, and then use a sharp knife to equally divide the whole plant of non viviparous tropical water lilies into 2 to 4 pieces starting from the root. Avoid damaging the small leaves and leaf bud points during the division process. Each divided plant should contain at least 1 healthy leaf bud point and several mature leaves to obtain the divided plants of non viviparous tropical water lilies; Step S4, selection and treatment of planting soil: Select garden soil or pond soil rich in humus and with good structure as the planting soil. Dry it thoroughly in the sun and then crush it, filtering out obvious gravel and sundries. The pH value of the planting soil is 5.6 - 7.5; Step S5, selection of planting site: The requirements for selecting the site are an open area with a drainage device, a water depth maintained at 50cm - 70cm, still water or slow water flow speed, no obstruction around, sufficient sunlight, and wind force below level 4; Step S6, planting: In the planting site selected in Step S5, adopt the method of potted submerged planting. Fill the potted plant with the planting soil in Step S4. When it is 80% full, add water to make it into a thin mud shape. Then plant the divided plants of non viviparous tropical water lilies obtained in Step S3 in the center of the pot. Plant 1 divided plant in each pot, keeping the leaf bud point level with the planting soil surface. The water level is maintained at 5cm - 10cm above the leaf bud point in the early stage, and gradually increased to 15cm - 40cm in the later stage; Step S7, daily maintenance and management: Regularly remove the old leaves and yellow leaves. If the water quality turns black or stinks, change the water in time.

2. A method for vegetative propagation by dividing living plants of non viviparous tropical water lilies according to claim 1, characterized in that, in Step S2, the rinsing treatment is specifically: Remove the visible duckweed, spirogyra, snails and soil on the non viviparous tropical water lilies, and remove the old leaves, rotten leaves and diseased leaves on the non viviparous tropical water lilies, and protect the young leaves, tender leaves and bud points of the non viviparous tropical water lilies from being damaged during the treatment process.

3. A method for vegetative propagation by dividing living plants of non viviparous tropical water lilies according to claim 1, characterized in that, in Step S3, the sterilization treatment is specifically: Immerse it in a 800 - 1000 - fold solution of 50% carbendazim wettable powder for 1 - 1.5 hours, or spray it with a 1000 - fold solution of 70% thiophanate methyl wettable powder and then cover it with a film for 24 - hour sterilization treatment.

4. A method for vegetative propagation by dividing living plants of non viviparous tropical water lilies according to claim 1, characterized in that, In step S3, the sharp tool needs to be disinfected in advance.

5. A method for vegetative propagation of non viviparous tropical water lilies according to claim 1, characterized in that, In step S6, the water level above the leaf bud point in the early stage is maintained at 10 cm.

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