Efficient propagation method of asexually cutting of wild tea trees in tropics

Abstract

The application discloses a kind of tropical wild tea tree asexual cutting efficient breeding method, belong to tea tree asexual seedling breeding technical field.The application takes Hainan wild tea tree as object, through multi-factor system cutting test combined with entropy weight TOPSIS comprehensive evaluation, filters out the optimal cutting parameter combination of winter and spring season and summer and autumn season respectively, improves cutting survival rate and rooting rate, effectively solves the technical problem of Hainan wild tea tree cutting rooting difficulty, low survival rate.The application also discloses the seasonal hormone adaptation law that IAA is optimal in winter and spring season and NAA is optimal in summer and autumn season, provides scientific basis for year-round breeding.The application is simple in operation, low in cost, suitable for wild tea tree germplasm resource protection, population recovery and excellent single rapid cloning breeding, with remarkable economic value and ecological protection significance.

Description

Technical Field

[0001] This invention relates to the field of asexual propagation technology of tea trees, and in particular to a highly efficient method for asexual propagation of tropical wild tea trees by cuttings. Background Technology

[0002] Tea trees are an important economic crop, and currently, asexual propagation is mainly carried out through short-cutting propagation. Cutting propagation can maintain the superior traits of the parent plant and is a key technical means for breeding superior tea varieties. However, the survival rate of tea cuttings is affected by multiple factors, including the degree of lignification of the cuttings, the cutting substrate, the type and concentration of exogenous hormones, and the soaking time.

[0003] Due to the long-term natural growth of wild tea trees, the rooting ability of their cuttings is often weaker than that of cultivated varieties. Difficulty in rooting and low survival rates are major challenges hindering the production of wild tea tree seedlings and the protection of germplasm resources in Hainan. Existing research on tea tree cuttings mainly focuses on cultivated varieties, with a lack of systematic research on the propagation of tropical wild tea trees by cuttings. Previous studies have shown that different hormone treatments have a significant impact on the rooting rate of tea tree cuttings, but how multiple factors such as hormone type (IAA, IBA, NAA, etc.), concentration, soaking time, substrate ratio, and the degree of lignification of the cuttings synergistically affect the cutting effect of tropical wild tea trees is currently lacking systematic experimental data. Furthermore, whether there are differences in the rooting performance of wild tea tree cuttings under different seasonal conditions has not been clearly reported. Summary of the Invention

[0004] The purpose of this invention is to provide an efficient method for the asexual propagation of tropical wild tea trees by cuttings. Based on the characteristics of tropical wild tea trees, a multi-factor, multi-level systematic cutting experiment was conducted to screen out suitable conditions for the asexual propagation of tropical wild tea trees by cuttings, providing technical support for the protection and development of wild tea tree germplasm resources.

[0005] To achieve the above objectives, this invention provides a highly efficient method for the asexual propagation of tropical wild tea trees by cuttings, comprising the following steps: S1. Cutting preparation: Cuttings are taken from tropical wild tea trees and divided into short cuttings and long cuttings according to their length; S2. Substrate preparation: Mix loess and river sand evenly in proportion to use as cutting substrate, and spray the substrate evenly with diluted carbendazim wettable powder for sterilization, and let it dry for one day. S3. Hormone treatment: The cuttings obtained in S1 are immersed in a hormone solution with a hormone concentration of 200 mg / L to 1000 mg / L and an immersion time of 60 s to 1800 s. S4. Cuttings: After being treated in S3, the cuttings are dipped in red mud slurry and then inserted into the substrate prepared in S2. S5. Post-cutting management: After cutting, cover with a film to retain moisture, and only water the furrows; remove the film every 15 days and alternate between dilute thiophanate-methyl wettable powder and dilute carbendazim wettable powder for sterilization, repeating 2-3 times.

[0006] Preferably, in S1, the cutting is a semi-lignified branch, the short cutting is 5cm long, and the long cutting is 15cm long.

[0007] Preferably, in S2, the volume ratio of loess to river sand is 2:1; the active ingredient content of the carbendazim wettable powder is 50%, and the dilution factor is 500 times.

[0008] Preferably, in S3, the hormone is any one of IAA, IBA, and NAA.

[0009] Preferably, the hormone is IAA, the hormone concentration is 500 mg / L, and the soaking time is 600 s.

[0010] Preferably, the hormone is NAA, the hormone concentration is 500 mg / L, and the soaking time is 600 s.

[0011] Preferably, the hormone is IBA, the hormone concentration is 500 mg / L or 1000 mg / L, and the soaking time is 1800 s.

[0012] The preferred process conditions for winter and spring cutting propagation are: substrate loess: river sand = 2:1, cuttings are 5cm semi-lignified short cuttings, hormone is IAA, concentration is 500mg / L, soaking time is 600s.

[0013] The preferred process conditions for summer and autumn cutting propagation are: substrate loess: river sand = 2:1, cuttings are 5cm semi-lignified short cuttings, hormone is NAA, concentration is 500mg / L, soaking time is 600s.

[0014] This invention employs a highly efficient asexual propagation method for tropical wild tea trees, using Hainan wild tea trees as the target. Through multi-factor systematic cutting experiments, it establishes the optimal parameter system for asexual cutting of Hainan wild tea trees, improving the survival rate and rooting rate of cuttings. Simultaneously, it reveals the hormone adaptation patterns of Hainan wild tea trees in different seasons, showing that IAA is optimal in winter and spring, while NAA is optimal in summer and autumn, providing a scientific basis for year-round propagation. This invention is simple to operate, low in cost, and suitable for the protection of Hainan wild tea tree germplasm resources, population restoration, and rapid cloning and propagation of superior individual plants, possessing significant economic value and ecological protection significance.

[0015] The technical solution of the present invention will be further described in detail below through embodiments. Detailed Implementation

[0016] The technical solutions of the present invention are further illustrated by the following embodiments. Unless otherwise defined, the technical or scientific terms used in this invention should be understood in their ordinary sense by those skilled in the art. Those skilled in the art should understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products. It should be particularly noted that all the following embodiments and comparative experiments use wild tea trees collected from Hainan Island as the test subjects, and all cuttings used are derived from wild tea tree mother plants in Hainan.

[0017] The following examples are based on a total of 432 single-factor cutting experiments conducted in winter and spring with different factors and levels (factors include season, substrate ratio, hormone type, hormone concentration, soaking time, lignification degree and cutting length), and a total of 360 summer and autumn experimental combinations. Each treatment was set up with 3 replicates, and each replicate had 30 branches. The optimal treatment was selected by combining the entropy weight TOPSIS comprehensive evaluation method.

[0018] Example 1: Optimal treatment scheme for winter and spring.

[0019] This embodiment provides a highly efficient method for the asexual propagation of tropical wild tea trees by cuttings, including the following steps: S1. Preparation of cuttings: In winter and spring (December to February of the following year), semi-lignified branches are cut from tropical wild tea trees in Hainan. The branches are cut into short cuttings, each 5cm long, with 30 branches per group.

[0020] S2. Substrate Preparation: Mix loess and river sand evenly at a volume ratio of 2:1 to serve as the cutting substrate. Dilute 50% carbendazim wettable powder (brand: Guoguang) with water 500 times, and spray the diluted fungicide evenly on the test ridges and test area for sterilization. Let it dry for one day.

[0021] S3. Hormone treatment: The cuttings obtained in S1 were immersed in an IAA (indoleacetic acid) hormone solution with a hormone concentration of 500 mg / L for 600 seconds.

[0022] S4. Cuttings: After being treated in S3, the cuttings are dipped in red mud slurry and then inserted into the substrate prepared in S2.

[0023] S5. Post-cutting management: After cutting, cover with a film to retain moisture. To ensure the stability of the growth environment inside the film, watering should only be done in the furrows. Remove the film every 15 days and alternately use 500 times diluted thiophanate-methyl wettable powder and 500 times diluted carbendazim wettable powder for sterilization, repeating 2-3 times.

[0024] One month after cutting, the time of callus formation and rooting was recorded. Five months after cutting, the number of callus and roots were counted, the root length was measured, and the rooting rate and survival rate of the cuttings were calculated.

[0025] Using the method described in this embodiment, the callus formation rate reached 30.39%, and the survival rate reached 86.73%. According to the entropy weight TOPSIS comprehensive evaluation, this embodiment ranked first among all 432 treatments, making it the optimal breeding scheme for winter and spring.

[0026] Example 2: Winter and Spring IBA Treatment Scheme.

[0027] This embodiment provides a highly efficient method for the asexual propagation of tropical wild tea trees by cuttings. The steps are the same as in Embodiment 1, except that: In S3, the hormone is IBA (indolebutyric acid), the hormone concentration is 500 mg / L or 1000 mg / L, and the soaking time is 1800 s.

[0028] Using the method described in this embodiment, when the IBA concentration was 500 mg / L and the soaking time was 1800 s, the callus formation rate was 18.29%, the survival rate was 92.78%, the rooting rate was 74.53%, and the number of roots was 9. Based on the entropy-weighted TOPSIS comprehensive evaluation, it ranked 3rd out of all 432 treatments.

[0029] When the IBA concentration was 1000 mg / L and the soaking time was 1800 s, it ranked second among all 432 treatments.

[0030] Example 3: NAA treatment scheme for winter and spring.

[0031] This embodiment provides a highly efficient method for the asexual propagation of tropical wild tea trees by cuttings. The steps are the same as in Embodiment 1, except that: In S3, the hormone is NAA (naphthaleneacetic acid), the hormone concentration is 500 mg / L, and the soaking time is 600 s.

[0032] Using the method described in this embodiment, the callus formation rate was 17.92%, the survival rate was 92.34%, the rooting rate was 74.41%, and the root length was 7.85 cm. Based on the entropy-weighted TOPSIS comprehensive evaluation, it ranked 6th out of all 432 treatments.

[0033] Example 4: Optimal solution for summer and autumn.

[0034] This embodiment provides a highly efficient method for the asexual propagation of tropical wild tea trees by cuttings, including the following steps: S1. Cutting preparation: In summer and autumn (June to August), semi-lignified branches are cut from tropical wild tea trees in Hainan. The branches are cut into short cuttings, each 5cm long, with 30 branches per group.

[0035] S2. Substrate Preparation: Mix loess and river sand evenly at a volume ratio of 2:1 to serve as the cutting substrate. Dilute 50% carbendazim wettable powder with water 500 times, and spray the diluted fungicide evenly on the test ridges and test area for sterilization. Let it dry for one day.

[0036] S3. Hormone treatment: The cuttings obtained in S1 were immersed in NAA hormone solution at a concentration of 500 mg / L for 600 seconds.

[0037] S4. Cuttings: After being treated in S3, the cuttings are dipped in red mud slurry and then inserted into the substrate prepared in S2.

[0038] S5. Post-cutting management: After cutting, cover with a thin film to retain moisture, and water only in the furrows; remove the film every 15 days, and alternate between 500 times diluted thiophanate-methyl wettable powder and 500 times diluted carbendazim wettable powder for sterilization, repeating 2-3 times.

[0039] Using the method described in this embodiment, the callus formation rate was 14.15%, the survival rate was 83.00%, and the rooting rate was 83.00%. Based on the TOPSIS comprehensive evaluation, it ranked first among all 360 treatments, making it the optimal propagation scheme for summer and autumn.

[0040] Example 5: Comparison test of different matrix ratios.

[0041] To verify the optimal effect of the substrate ratio of the present invention, the following comparative experiment was conducted. Except for the substrate ratio, all other factors were kept consistent for each treatment: the hormone was IAA, the concentration was 200 mg / L, the soaking time was 60 s, the cuttings were semi-lignified short cuttings (5 cm), and the cuttings were taken in winter or spring.

[0042] Experimental Group 1: The matrix was loess: river sand = 1:0 (volume ratio), and the other conditions were the same as above.

[0043] Experimental Group 2: The matrix was loess: river sand = 2:1 (volume ratio), and the other conditions were the same as above.

[0044] Experimental Group 3: The matrix was loess:river sand = 4:1 (volume ratio), and the other conditions were the same as above.

[0045] The experimental results are shown in Table 1.

[0046] Table 1. Effects of different substrate ratios on cutting propagation results

[0047] The results showed that when the matrix was loess:river sand = 2:1, the survival rate reached 82.16%, which was better than other ratios.

[0048] Example 6: Comparative experiment of different types of hormones.

[0049] To verify the optimal effect of hormone selection in this invention, the following comparative experiment was conducted. Except for the type of hormone, all other factors were kept consistent for each treatment: the substrate was loess:river sand = 1:0, the hormone concentration was 200 mg / L, the soaking time was 60 seconds, and the cuttings were lignified short cuttings (5 cm), taken in winter or spring.

[0050] Experimental group 1: The hormone was IAA, and all other conditions were the same as above.

[0051] Experimental group 2: The hormone was IBA, and all other conditions were the same as above.

[0052] Experimental group 3: The hormone was NAA, and all other conditions were the same as above.

[0053] Control group: Water (CK) was used instead of hormone solution, and all other conditions were the same as above.

[0054] The experimental results are shown in Table 2.

[0055] Table 2. Effects of different hormone types on cutting propagation results

[0056] The results showed that the survival rate and rooting rate of the patients treated with IAA, IBA and NAA hormones were significantly higher than those of the water control. Among them, the survival rate and number of roots were the highest after IBA treatment, and the root length was the longest after NAA treatment.

[0057] Example 7: Comparison test of different hormone concentrations.

[0058] To verify the optimal effect of the hormone concentration of the present invention, the following comparative experiment was conducted. Except for the hormone concentration, all other factors were kept consistent for each treatment: the substrate was loess:river sand = 1:0, the hormone was IAA, the soaking time was 60s, and the cuttings were lignified short cuttings (5cm), which were planted in winter or spring.

[0059] Experimental group 1: hormone concentration was 200 mg / L, and other conditions were the same as above.

[0060] Experimental group 2: hormone concentration was 500 mg / L, and other conditions were the same as above.

[0061] Experimental group 3: hormone concentration was 1000 mg / L, and other conditions were the same as above.

[0062] The experimental results are shown in Table 3.

[0063] Table 3. Effects of different hormone concentrations on cutting propagation results

[0064] The results showed that the survival rate and rooting rate at concentrations of 500 mg / L and 1000 mg / L were significantly higher than those at 200 mg / L. Based on the comprehensive TOPSIS evaluation, 500 mg / L was the optimal concentration.

[0065] Example 8: Comparison test of different soaking times.

[0066] To verify the optimal soaking time of this invention, the following comparative experiment was conducted. Except for the soaking time, all other factors were kept consistent for each treatment: the substrate was loess:river sand = 1:0; the hormone was IAA at a concentration of 200 mg / L; the cuttings were semi-lignified short cuttings (5 cm), and the cuttings were taken in winter or spring.

[0067] Experimental group 1: Soaking time was 60 seconds, and all other conditions were the same as above.

[0068] Experimental group 2: Soaking time was 600s, and other conditions were the same as above.

[0069] Experimental group 3: Soaking time was 1800s, and other conditions were the same as above.

[0070] The experimental results are shown in Table 4.

[0071] Table 4. Effects of different soaking times on cutting propagation results

[0072] The results showed that there was no significant difference in survival rate under the three soaking times, but the rooting rate was highest under the 1800s treatment. The TOPSIS evaluation showed that 600s was the optimal result.

[0073] Example 9: Comparative test of different degrees of lignification.

[0074] To verify the optimal effect of the lignification degree of the cuttings in this invention, the following comparative experiment was conducted. Except for the lignification degree, all other factors were kept consistent for each treatment: the substrate was loess:river sand = 1:0, the hormone was IAA at a concentration of 200 mg / L, the soaking time was 60 s, and the cuttings were short (5 cm), and the cuttings were taken in winter or spring.

[0075] Experimental group: Semi-lignified branches were used, and all other conditions were the same as above.

[0076] Control group: lignified branches were used, and all other conditions were the same as above.

[0077] The experimental results are shown in Table 5.

[0078] Table 5. Effects of cuttings with different degrees of lignification on propagation results

[0079] The results showed that the callus formation rate, survival rate and root length of semi-lignified branches were higher than those of lignified branches, indicating that semi-lignified branches had a significant advantage in growth capacity.

[0080] Example 10: Comparison test of different spikelet lengths.

[0081] To verify the optimal effect of the cutting length in this invention, the following comparative experiment was conducted. Except for the cutting length, all other factors were kept consistent for each treatment: the substrate was loess:river sand = 1:0, the hormone was IAA at a concentration of 200 mg / L, the soaking time was 60 s, and the cuttings were semi-lignified branches, which were planted in winter or spring.

[0082] Experimental group: Short spikelets (5cm) were used, and the other conditions were the same as above.

[0083] Control group: Long spikes (15cm) were used, and all other conditions were the same as above.

[0084] The experimental results are shown in Table 6.

[0085] Table 6. Effects of different cutting lengths on propagation results

[0086] The results showed that the callus formation and survival rate of short spikelets were slightly higher than those of long spikelets, and short spikelets were more conducive to callus formation and scion survival.

[0087] Therefore, this invention adopts the above-mentioned efficient propagation method of asexual cutting of tropical wild tea trees and conducts a multi-factor, multi-level systematic cutting experiment on tropical wild tea trees in Hainan. Through single-factor experimental design, the effects of factors such as season, substrate ratio, hormone type, hormone concentration, soaking time, lignification degree and cutting length on callus occurrence rate, survival rate, rooting rate, number of roots and root length were systematically investigated. The optimal treatment combination was screened by combining the entropy weight TOPSIS comprehensive evaluation method.

[0088] The experimental results showed that the optimal treatment in winter and spring was a substrate of loess:river sand = 2:1, hormone IAA concentration of 500 mg / L, soaking time of 600 s, cutting length of 5 cm, and semi-lignification, ranking first in TOPSIS among 432 treatments. The optimal treatment in summer and autumn was also a substrate of loess:river sand = 2:1, hormone NAA concentration of 500 mg / L, soaking time of 600 s, cutting length of 5 cm, and semi-lignification, ranking first in TOPSIS among 360 treatments. All treatments exhibited three rooting types: callus rooting, bark rooting, and mixed rooting. Callus rooting was the most prevalent, followed by mixed rooting, and then bark rooting.

[0089] Using the method of this invention, the survival rate of cuttings taken in winter and spring reaches 92.78%, and the rooting rate reaches 74.53%; the survival rate of cuttings taken in summer and autumn can reach over 83.00%, and the rooting rate can reach 83.00%, which is significantly better than the water control group (survival rate of only 32.96%). This invention effectively solves the technical problems of difficult rooting and low survival rate of cuttings of tropical wild tea trees, and provides reliable technical support for the protection and development of wild tea tree germplasm resources.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A highly efficient method for asexual propagation of tropical wild tea trees by cuttings, characterized in that, Includes the following steps: S1. Cutting preparation: Cuttings are taken from tropical wild tea trees and divided into short cuttings and long cuttings according to their length; S2. Substrate preparation: Mix loess and river sand evenly in proportion to use as cutting substrate, and spray the substrate evenly with diluted carbendazim wettable powder for sterilization, and let it dry for one day. S3. Hormone treatment: The cuttings obtained in S1 are immersed in a hormone solution with a hormone concentration of 200 mg / L to 1000 mg / L and an immersion time of 60 s to 1800 s. S4. Cuttings: After being treated in S3, the cuttings are dipped in red mud slurry and then inserted into the substrate prepared in S2. S5. Post-cutting management: After cutting, cover with a film to retain moisture, and only water the furrows; remove the film every 15 days and alternate between dilute thiophanate-methyl wettable powder and dilute carbendazim wettable powder for sterilization, repeating 2-3 times.

2. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 1, characterized in that, In S1, the cuttings are semi-lignified branches, the short cuttings are 5cm long, and the long cuttings are 15cm long.

3. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 1, characterized in that, In S2, the volume ratio of loess to river sand is 2:1; the active ingredient content of the carbendazim wettable powder is 50%, and the dilution factor is 500 times.

4. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 1, characterized in that, In S3, the hormone is any one of IAA, IBA, and NAA.

5. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 4, characterized in that, The hormone used was IAA, with a concentration of 500 mg / L, and the soaking time was 600 seconds.

6. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 4, characterized in that, The hormone used was NAA, with a concentration of 500 mg / L, and the soaking time was 600 seconds.

7. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 4, characterized in that, The hormone is IBA, with a concentration of 500 mg / L or 1000 mg / L, and the soaking time is 1800 s.

8. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 1, characterized in that, The technical conditions for winter and spring cutting propagation are as follows: substrate: loess: river sand = 2:1, cuttings are 5cm semi-lignified short cuttings, hormone is IAA, concentration is 500mg / L, soaking time is 600s.

9. The method for efficient asexual propagation of tropical wild tea trees by cuttings according to claim 1, characterized in that, The technical conditions for propagation by cuttings in summer and autumn are as follows: the substrate ratio of loess to river sand is 2:1, the cuttings are 5cm semi-lignified short cuttings, the hormone is NAA at a concentration of 500mg / L, and the soaking time is 600s.

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