Method for regulating the germination and growth of platycodon grandiflorum by allelopathy between medicinal materials and application thereof

Abstract

The application discloses a method for regulating the germination and growth of platycodon grandiflorum by allelopathy between medicinal materials and application thereof, and uses water extraction of traditional Chinese medicinal materials to carry out allelopathy treatment on platycodon grandiflorum seeds to regulate the germination and growth of the platycodon grandiflorum, wherein the traditional Chinese medicinal materials are any one of radix cyathulae, radix saposhnikoviae and radix adnati; the water extraction of traditional Chinese medicinal materials is any one of water extraction of radix cyathulae, water extraction of radix saposhnikoviae and water extraction of radix adnati; the concentration of the water extraction of radix cyathulae is 10-20 mg / ml; the concentration of the water extraction of radix saposhnikoviae is 10-30 mg / ml; and the concentration of the water extraction of radix adnati is 20-30 mg / ml; the application takes radix adnati, radix cyathulae and radix saposhnikoviae as research objects, studies the allelopathy of the water extraction of the three kinds of traditional Chinese medicinal materials on the germination and seedling growth of the platycodon grandiflorum, and selects the most suitable traditional Chinese medicinal material for intercropping with the platycodon grandiflorum and a treatment method before intercropping, thereby laying a foundation for the selection of the platycodon grandiflorum and other intercropped medicinal materials in the future.

Description

Technical Field

[0001] This invention relates to the field of Platycodon grandiflorus propagation technology, specifically to a method and its application of regulating the germination and growth of Platycodon grandiflorus using allelopathic effects among medicinal materials. Background Technology

[0002] Kalaqin Banner in Chifeng City, Inner Mongolia, is one of the major producing areas of medicinal herbs in China. Currently, the main medicinal herbs cultivated are Platycodon grandiflorus, Adenophora stricta, Saposhnikovia divaricata, and Achyranthes bidentata. However, due to long-term unregulated cultivation of medicinal herbs, continuous cropping obstacles have frequently occurred in recent years, resulting in a continuous decline in the yield of medicinal herbs and farmers' economic income. At present, the main planting methods are intercropping or crop rotation of the four medicinal herbs, but these have not been able to effectively solve the above problems. Therefore, finding a sustainable planting method is one of the important ways to solve this problem.

[0003] Intercropping is a widely used farming method in traditional Chinese agriculture. Reasonable intercropping not only improves land utilization, increases and stabilizes yields, and controls pests, diseases, and weeds, but also improves soil structure and fertility. It is an important measure commonly used in agricultural cultivation to increase crop yield and economic benefits. Whether intercropping between crops is appropriate depends first on the allelopathic effects between them. Allelopathy is a way for plants to exchange information; almost all plants produce substances containing allelopathic components, which can affect other species to varying degrees. Therefore, there is an urgent need for a method and its application that utilizes the allelopathic effects between medicinal herbs to regulate the germination and growth of Platycodon grandiflorus. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention focuses on three other medicinal herbs, besides Platycodon grandiflorus, that are mainly cultivated in Kalaqin Banner, Chifeng City: Adenophora stricta, Achyranthes bidentata, and Saposhnikovia divaricata. The allelopathic effects of water extracts from these three herbs on Platycodon grandiflorus seed germination and seedling growth were studied. The most suitable herbs for intercropping with Platycodon grandiflorus were selected, laying the foundation for future selection of other intercropping herbs for Platycodon grandiflorus. This has significant implications for adjusting the future medicinal herb planting structure and the sustainable development of the Platycodon grandiflorus medicinal herb industry, as detailed below:

[0005] A method for regulating the germination and growth of Platycodon grandiflorus using allelopathic effects among medicinal herbs involves treating Platycodon grandiflorus seeds with aqueous extracts of medicinal herbs to regulate their germination and growth. The medicinal herbs are any one of Achyranthes bidentata, Saposhnikovia divaricata, and Adenophora stricta. The aqueous extracts are any one of Achyranthes bidentata, Saposhnikovia divaricata, and Adenophora stricta. The concentration of the Achyranthes bidentata extract is 10-20 mg / ml; the concentration of the Saposhnikovia divaricata extract is 10-30 mg / ml; and the concentration of the Adenophora stricta extract is 20-30 mg / ml.

[0006] Preferably, the method for preparing the Achyranthes bidentata aqueous extract is as follows:

[0007] The roots of Achyranthes bidentata are cut into 1.5-2.5 cm long sections, crushed, and passed through a 50-70 mesh sieve. Water is added to prepare an Achyranthes bidentata aqueous extract with a concentration of 90-110 mg / ml. The extract is then ultrasonically treated for 2.5-3.5 h and allowed to stand at low temperature for 40-55 h. After filtration, the extract is diluted with distilled water to the required concentration to prepare the Achyranthes bidentata aqueous extract. The ultrasonic treatment intensity is 150-250 W and the frequency is 30-50 kHz.

[0008] Preferably, the method for preparing the water extract of Saposhnikovia divaricata is as follows:

[0009] Cut the roots of Saposhnikovia divaricata into 1.5-2.5cm long sections, crush them, pass them through a 50-70 mesh sieve, add water to make a Saposhnikovia divaricata aqueous extract with a concentration of 90-110mg / ml, then sonicate them on an ultrasonic treatment instrument for 2.5-3.5h, let them stand at low temperature for 40-55h, then filter them, and finally dilute them with distilled water to the required concentration to prepare the Saposhnikovia divaricata aqueous extract; the intensity of the ultrasonic treatment is 150-250W and the frequency is 30-50kHz.

[0010] Preferably, the method for preparing the aqueous extract of *Adenophora stricta* is as follows:

[0011] The roots of *Adenophora stricta* are cut into 1.5-2.5 cm long segments, crushed, and passed through a 50-70 mesh sieve. Water is added to prepare a *Adenophora stricta* aqueous extract with a concentration of 90-110 mg / ml. The extract is then ultrasonically treated for 2.5-3.5 h and allowed to stand at low temperature for 40-55 h. After filtration, the extract is diluted with distilled water to the required concentration to prepare the *Adenophora stricta* aqueous extract. The ultrasonic treatment intensity is 150-250 W and the frequency is 30-50 kHz.

[0012] Preferably, a method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effects among medicinal materials includes the following steps:

[0013] S1. Pretreatment of Platycodon grandiflorus seeds: Select plump, healthy, and disease-free Platycodon grandiflorus seeds, disinfect them with 0.1% potassium permanganate for 4-6 minutes, and then rinse them with distilled water 3-4 times.

[0014] S2. Add the Chinese medicinal herb water extract to the Platycodon grandiflorus seeds treated in step S1, ensuring that the liquid level of the Chinese medicinal herb water extract completely covers the Platycodon grandiflorus seeds, and then add an equal volume of distilled water. Soak for 20-28 hours.

[0015] On the other hand, the present invention provides an application of a method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effect between medicinal materials, wherein Platycodon grandiflorus seeds treated with liquefaction of Achyranthes bidentata water extract are intercropped with Achyranthes bidentata seeds.

[0016] Alternatively, intercropping can be carried out between Platycodon grandiflorus seeds treated with allelopathic extract of Adenophora stricta and Adenophora stricta seeds.

[0017] Alternatively, intercropping can be carried out between Platycodon grandiflorus seeds treated with allelopathic extract of Saposhnikovia divaricata and Saposhnikovia divaricata seeds.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. This invention focuses on three other medicinal herbs, besides Platycodon grandiflorus, that are mainly grown in Kalaqin Banner, Chifeng City: Adenophora stricta, Achyranthes bidentata, and Saposhnikovia divaricata. Through the study of the allelopathic effects of water extracts of these three herbs on the seed germination and seedling growth of Platycodon grandiflorus, the most suitable herbs for intercropping with Platycodon grandiflorus and the pre-intercropping treatment methods were selected. This lays the foundation for the future selection of Platycodon grandiflorus and other intercropping herbs, and is of great significance for the adjustment of future medicinal herb planting structures and the sustainable development of the Platycodon grandiflorus medicinal herb industry.

[0020] 2. This invention provides a method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic interaction between medicinal materials. Specifically, it involves using water extracts of traditional Chinese medicinal materials to perform allelopathic treatment on Platycodon grandiflorus seeds to regulate their germination and growth. The selected water extracts are Achyranthes bidentata water extract, Saposhnikovia divaricata water extract, and Adenophora stricta water extract. The concentration of Achyranthes bidentata water extract is 10-20 mg / ml; the concentration of Saposhnikovia divaricata water extract is 10-30 mg / ml; and the concentration of Adenophora stricta water extract is 20-30 mg / ml. Attached Figure Description

[0021] Figure 1 The effect of different concentrations of aqueous extracts of traditional Chinese medicinal materials on the germination rate of Platycodon grandiflorus;

[0022] Figure 2 The effect of different concentrations of aqueous extracts of Chinese medicinal herbs on the germination potential of Platycodon grandiflorus;

[0023] Figure 3 The effect of different concentrations of aqueous extracts of traditional Chinese medicinal materials on the germination index of Platycodon grandiflorus;

[0024] Figure 4 The effect of different concentrations of medicinal extracts on the root length of Platycodon grandiflorus seedlings;

[0025] Figure 5 The effect of different concentrations of herbal extracts on the seedling height of Platycodon grandiflorus seedlings;

[0026] Figure 6 The effect of different concentrations of medicinal herb extracts on SOD enzyme activity in Platycodon grandiflorus seedlings;

[0027] Figure 7 The effect of different concentrations of medicinal herb extracts on POD enzyme activity in Platycodon grandiflorus seedlings;

[0028] Figure 8 The effect of different concentrations of herbal extracts on the CAT enzyme activity of Platycodon grandiflorus seedlings. Detailed Implementation

[0029] Examples 1-3

[0030] A method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effect between medicinal materials involves treating Platycodon grandiflorus seeds with an aqueous extract of a traditional Chinese medicine to regulate its germination and growth. The medicinal material is Achyranthes bidentata; the aqueous extract of the medicinal material is Achyranthes bidentata aqueous extract; the concentration of the Achyranthes bidentata aqueous extract is shown in Table 1.

[0031] Furthermore, the method for preparing the Achyranthes bidentata aqueous extract is as follows:

[0032] After the roots of Achyranthes bidentata were cut into small sections and crushed, sieved, and then water was added to make an Achyranthes bidentata water extract. The extract was then subjected to ultrasonic treatment on an ultrasonic processor, allowed to stand at low temperature, filtered, and finally diluted with distilled water to the required concentration to prepare an Achyranthes bidentata water extract. The intensity frequency of the ultrasonic treatment is shown in Table 1.

[0033] The length of the cut sections of Achyranthes bidentata root, the mesh size of the sieve, the concentration of the Achyranthes bidentata water extract, and the low-temperature standing time are shown in Table 1.

[0034] Furthermore, a method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effects between medicinal materials includes the following steps:

[0035] S1. Pretreatment of Platycodon grandiflorus seeds: Select plump, healthy, and disease-free Platycodon grandiflorus seeds, disinfect them with 0.1% potassium permanganate, and then rinse them with distilled water; the potassium permanganate disinfection time and the number of times to rinse with distilled water are shown in Table 1.

[0036] S2. Add the Chinese herbal medicine water extract to the Platycodon grandiflorus seeds treated in step S1, so that the liquid level of the Chinese herbal medicine water extract covers the Platycodon grandiflorus seeds, and then add an equal volume of distilled water. Soak for 24 hours.

[0037] Table 1 Parameters of Examples 1-3

[0038]

[0039] Examples 4-6

[0040] A method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effect between medicinal materials involves treating Platycodon grandiflorus seeds with an aqueous extract of a traditional Chinese medicine to regulate its germination and growth. The medicinal material is Saposhnikovia divaricata; the aqueous extract of the medicinal material is Saposhnikovia divaricata aqueous extract; the concentration of the Saposhnikovia divaricata aqueous extract is shown in Table 2.

[0041] Furthermore, the preparation method of the water extract of *Saposhnikovia divaricata* is as follows:

[0042] The roots of Saposhnikovia divaricata were cut into small sections, crushed, sieved, and then water was added to make Saposhnikovia divaricata water extract. The extract was then ultrasonically treated on an ultrasonic processor, allowed to stand at low temperature, filtered, and finally diluted with distilled water to the required concentration to prepare Saposhnikovia divaricata water extract. The intensity frequency of the ultrasonic treatment is shown in Table 2.

[0043] Table 2 shows the length of the root cuttings, the mesh size of the sieve, the concentration of the water immersion solution for the root of Saposhnikovia divaricata, and the low-temperature standing time.

[0044] Furthermore, a method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effects between medicinal materials includes the following steps:

[0045] S1. Pretreatment of Platycodon grandiflorus seeds: Select plump, healthy, and disease-free Platycodon grandiflorus seeds, disinfect them with 0.1% potassium permanganate, and then rinse them with distilled water; the potassium permanganate disinfection time and the number of rinsing times with distilled water are shown in Table 2.

[0046] S2. Add the Chinese herbal medicine water extract to the treated Platycodon grandiflorus seeds in step S1, ensuring that the water extract completely covers the seed surface. Then add an equal volume of distilled water and soak for 24 hours.

[0047] Table 2 Parameters of Examples 4-6

[0048]

[0049] Examples 7-9

[0050] A method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effect between medicinal materials involves treating Platycodon grandiflorus seeds with an aqueous extract of a traditional Chinese medicine to regulate its germination and growth. The medicinal material is Adenophora stricta; the aqueous extract is Adenophora stricta aqueous extract; and the concentration of the Adenophora stricta aqueous extract is shown in Table 3.

[0051] Furthermore, the preparation method of the North American ginseng water extract is as follows:

[0052] The roots of *Adenophora stricta* were cut into small sections, crushed, sieved, and then water was added to prepare *Adenophora stricta* aqueous extract. The extract was then subjected to ultrasonic treatment on an ultrasonic processor, allowed to stand at low temperature, filtered, and finally diluted with distilled water to the required concentration to prepare *Adenophora stricta* aqueous extract. The intensity and frequency of the ultrasonic treatment are shown in Table 3.

[0053] Table 3 shows the length of the small sections of North American ginseng root, the mesh size of the sieve, the concentration of the North American ginseng water extract, and the low-temperature standing time.

[0054] Furthermore, a method for regulating the germination and growth of Platycodon grandiflorus by utilizing the allelopathic effects between medicinal materials includes the following steps:

[0055] S1. Pretreatment of Platycodon grandiflorus seeds: Select plump, healthy, and disease-free Platycodon grandiflorus seeds, disinfect them with 0.1% potassium permanganate, and then rinse them with distilled water; the potassium permanganate disinfection time and the number of rinsing times with distilled water are shown in Table 3.

[0056] S2. Add the Chinese herbal medicine water extract to the treated Platycodon grandiflorus seeds in step S1, ensuring that the liquid level of the Chinese herbal medicine water extract completely covers the Platycodon grandiflorus seeds, and then add an equal volume of distilled water. Soak for 24 hours.

[0057] Table 3 Parameters of Examples 7-9

[0058]

[0059] Experimental Section

[0060] Experiment 1

[0061] (1) Preparation of aqueous extracts from different Chinese medicinal materials:

[0062] The roots of the Chinese medicinal herbs Achyranthes bidentata, Saposhnikovia divaricata, Adenophora stricta, and Platycodon grandiflorus were cut into small sections about 2 cm long and then crushed. After passing through a 60-mesh sieve, 30 g of each herb powder was weighed out and 300 ml of distilled water was added to prepare an aqueous extract with a concentration of 100 mg / ml. The extract was ultrasonically treated for 3 hours, then allowed to stand at low temperature for 48 hours, and then filtered. Finally, the aqueous extract was diluted with distilled water to concentrations of 5, 10, 20, 30, and 50 mg / ml, respectively, for later use. A distilled water control group was also set up.

[0063] (2) Pretreatment of Platycodon grandiflorus seeds:

[0064] Fifty plump, healthy, and disease-free Platycodon grandiflorus seeds were selected, disinfected with 0.1% potassium permanganate for 5 minutes, and then rinsed with distilled water 3-4 times. The 50 disinfected seeds were neatly arranged on a paper germination bed in a petri dish with a diameter of 9 cm. Then, 2 ml of the corresponding water extract of the medicinal material was added to each dish. The control group was treated with an equal volume of distilled water. The experiment was repeated 3 times.

[0065] (3) Culture of Platycodon grandiflorus seeds:

[0066] Place the prepared petri dishes in a constant temperature incubator at 25℃ with 12 hours of darkness and 12 hours of light for germination. Observe and record the number of germinated Platycodon grandiflorus seeds daily, with the emergence of white seeds as the germination marker. Keep the seeds moist with the appropriate aqueous extract of traditional Chinese medicine, ensuring no water film forms around the seeds. The culture period is 14 days. After the culture period, calculate the germination rate, germination potential, and germination index of the Platycodon grandiflorus seeds. The germination rate is as follows: Figure 1 As shown, the germination rate is as follows Figure 2 As shown, the germination index is as follows Figure 3 As shown.

[0067] Germination rate (%) = (Number of seeds that germinated normally within 14 days / Total number of seeds tested) × 100%;

[0068] Germination potential (%) = (Number of germinated seeds on day 9 / Total number of seeds tested) × 100%;

[0069] Germination index = ∑Gt / Dt (where: Gt is the number of seeds that germinate each day during the germination test period; Dt is the corresponding number of days of seed germination)

[0070] from Figure 1 It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the germination rate of Platycodon grandiflorus. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the germination rate of Platycodon grandiflorus at 20 mg / ml and 30 mg / ml, both of which promote it by 9.58%. The aqueous extracts of Glehnia littoralis at 5 mg / ml and 10 mg / ml have a slight promoting effect, but the effect is not very obvious. The aqueous extract of Glehnia littoralis at 50 mg / ml shows an inhibitory effect.

[0071] The most significant promoting effects of Saposhnikovia divaricata aqueous extract on the germination rate of Platycodon grandiflorus were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, with increases of 2.58%, 6.24%, and 7.36%, respectively. The 5 mg / ml and 40 mg / ml aqueous extracts of Saposhnikovia divaricata showed slight promoting effects, but the effects were not significant, while the 50 mg / ml aqueous extract of Saposhnikovia divaricata showed an inhibitory effect.

[0072] The most significant promoting effects of Achyranthes bidentata aqueous extract on the germination rate of Platycodon grandiflorus were observed at concentrations of 10 mg / ml and 20 mg / ml, increasing it by 4.58% and 6.24%, respectively. Achyranthes bidentata aqueous extracts at concentrations of 5 mg / ml, 30 mg / ml, and 40 mg / ml showed some inhibitory effects, while the aqueous extract at 50 mg / ml exhibited a significant inhibitory effect.

[0073] from Figure 2 It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the germination potential of Platycodon grandiflorus. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the germination potential of Platycodon grandiflorus at 20 mg / ml and 30 mg / ml, promoting it by 12.42% and 10.12% respectively. The aqueous extracts of Glehnia littoralis at 40 mg / ml, 10 mg / ml and 5 mg / ml have a slight promoting effect, but the effect is not very obvious, while the aqueous extract of Glehnia littoralis at 50 mg / ml shows an inhibitory effect.

[0074] The most significant promoting effects of the aqueous extracts of Saposhnikovia divaricata on the germination potential of Platycodon grandiflorus were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, with increases of 11.01%, 11.11%, and 8.11%, respectively. The aqueous extract of Adenophora stricta at 5 mg / ml showed a slight promoting effect, but the effect was not significant, while the concentrations of 40 mg / ml and 50 mg / ml showed an inhibitory effect.

[0075] The most significant promoting effects of Achyranthes bidentata aqueous extract on the germination potential of Platycodon grandiflorus were observed at concentrations of 10 mg / ml and 20 mg / ml, with increases of 7% and 10.09%, respectively. Achyranthes bidentata aqueous extract at 5 mg / ml showed a slight promoting effect, while extracts at concentrations of 30 mg / ml, 40 mg / ml, and 50 mg / ml exhibited inhibitory effects.

[0076] from Figure 3 It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the germination index of Platycodon grandiflorus. The aqueous extract of Glehnia littoralis showed the most significant promotion on the germination index of Platycodon grandiflorus at 20 mg / ml and 30 mg / ml, promoting it by 4.06% and 3.48%, respectively. The aqueous extracts of Glehnia littoralis at 5 mg / ml and 10 mg / ml showed some promotion, but the effect was not very obvious. The aqueous extracts of Glehnia littoralis at 40 mg / ml and 50 mg / ml showed an inhibitory effect, with the inhibitory effect at 50 mg / ml being more obvious.

[0077] The most significant promoting effects of Saposhnikovia divaricata aqueous extract on the germination index of Platycodon grandiflorus were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, with increases of 1.26%, 2.11%, and 1.18%, respectively. The 40 mg / ml extract showed a slight promoting effect, but the effect was not significant. The 50 mg / ml and 5 mg / ml extracts exhibited inhibitory effects, with the 50 mg / ml extract showing the most pronounced inhibitory effect.

[0078] The most significant promoting effects of Achyranthes bidentata aqueous extract on the germination index of Platycodon grandiflorus were observed at concentrations of 10 mg / ml and 20 mg / ml, with increases of 7% and 10.09%, respectively; while Achyranthes bidentata aqueous extracts at concentrations of 5 mg / ml, 30 mg / ml, 40 mg / ml, and 50 mg / ml showed inhibitory effects.

[0079] Experiment 2

[0080] After the Platycodon grandiflorus seedlings that had sprouted in Experiment 1 were cultured hydroponically for another 72 hours, the root length, seedling height, and antioxidant enzyme activity (superoxide dismutase SOD, peroxidase POD, and catalase CAT) were measured. SOD activity was determined using the nitroblue tetrazolium (NBT) method, CAT activity using the UV absorption method, and POD activity using the guaiacol method. Root length was as follows... Figure 4 As shown, the seedling height is as Figure 5 As shown, superoxide dismutase (SOD) is... Figure 6 As shown, peroxidase POD Figure 7 As shown, catalase CAT is as follows Figure 8 As shown.

[0081] from Figure 4It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the root growth of Platycodon grandiflorus seedlings. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the root growth of Platycodon grandiflorus seedlings at 20 mg / ml and 30 mg / ml, promoting the root growth by 2.22 cm and 2.28 cm, respectively. The aqueous extracts of Glehnia littoralis at 5 mg / ml, 10 mg / ml and 40 mg / ml have a slight promoting effect, but the effect is not very obvious, while the aqueous extract of Glehnia littoralis at 50 mg / ml shows an inhibitory effect.

[0082] The most significant promoting effects of Saposhnikovia divaricata aqueous extract on root growth of Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, resulting in growth rates of 0.05 cm, 0.08 cm, and 0.06 cm, respectively. The 5 mg / ml and 10 mg / ml concentrations of Saposhnikovia divaricata aqueous extract showed slight promoting effects, but the effects were not significant. The 50 mg / ml concentration of Saposhnikovia divaricata aqueous extract exhibited an inhibitory effect.

[0083] The most significant promoting effects of Achyranthes bidentata aqueous extract on root growth of Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml and 20 mg / ml, promoting root growth by 0.33 cm and 0.42 cm, respectively. The 5 mg / ml Achyranthes bidentata aqueous extract showed some promoting effect, but the effect was not significant. The 30 mg / ml, 40 mg / ml, and 50 mg / ml Achyranthes bidentata aqueous extracts showed inhibitory effects.

[0084] from Figure 5 It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the height of Platycodon grandiflorus seedlings. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the height of Platycodon grandiflorus seedlings at 20 mg / ml and 30 mg / ml, promoting the height by 1.53 cm and 2.39 cm, respectively. The aqueous extracts of Glehnia littoralis at 5 mg / ml, 10 mg / ml and 40 mg / ml have a slight promoting effect, but the effect is not very obvious, while the aqueous extract of Glehnia littoralis at 50 mg / ml shows an inhibitory effect.

[0085] The most significant promoting effects of Saposhnikovia divaricata aqueous extract on the height of Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, resulting in height increases of 0.31 cm, 0.41 cm, and 0.27 cm, respectively. The 5 mg / ml Saposhnikovia divaricata aqueous extract showed some promotion, but the effect was not significant. The 40 mg / ml and 50 mg / ml Saposhnikovia divaricata aqueous extracts exhibited inhibitory effects.

[0086] The most significant promoting effects of Achyranthes bidentata aqueous extract on the height of Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml and 20 mg / ml, promoting height by 0.33 cm and 0.42 cm, respectively. The 5 mg / ml Achyranthes bidentata aqueous extract showed a slight promoting effect, but the effect was not significant. The 30 mg / ml, 40 mg / ml, and 50 mg / ml Achyranthes bidentata aqueous extracts showed inhibitory effects, with the 50 mg / ml Achyranthes bidentata aqueous extract showing the most significant inhibitory effect.

[0087] from Figure 6 It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the SOD enzyme activity of Platycodon grandiflorus seedlings. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the SOD enzyme activity of Platycodon grandiflorus seedlings at 20 mg / ml, 30 mg / ml, and 40 mg / ml, with the highest being 79.49 U / g / min. 5 mg / ml and 10 mg / ml are the next most effective. The aqueous extract of Glehnia littoralis at 50 mg / ml shows an inhibitory effect.

[0088] The most significant promoting effects of the aqueous extract of Saposhnikovia divaricata on the SOD enzyme activity of Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, with the highest concentration at 30 mg / ml, resulting in a promotion of 5.56 U / g / min. The concentrations of 5 mg / ml and 40 mg / ml were the next most significant, while the aqueous extract of Saposhnikovia divaricata at 50 mg / ml showed an inhibitory effect.

[0089] The most significant promoting effects of Achyranthes bidentata aqueous extract on SOD enzyme activity in Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, with the highest concentration at 30 mg / ml, resulting in a promotion of 4.47 U / g / min. The effects were followed by 5 mg / ml and 40 mg / ml, while 50 mg / ml of Achyranthes bidentata aqueous extract showed an inhibitory effect.

[0090] from Figure 7 It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the POD enzyme activity of Platycodon grandiflorus seedlings. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the POD enzyme activity of Platycodon grandiflorus seedlings at 20 mg / ml and 30 mg / ml, which are 58.01 U / g / min and 72.93 U / g / min, respectively. The following are 5 mg / ml and 10 mg / ml. The aqueous extract of Glehnia littoralis at 50 mg / ml shows an inhibitory effect.

[0091] The aqueous extracts of Saposhnikovia divaricata showed the most significant promoting effect on POD enzyme activity in Platycodon grandiflorus seedlings at concentrations of 10 mg / ml, 20 mg / ml, and 30 mg / ml, with a maximum promotion of 16.97 U / g / min; the aqueous extracts of Saposhnikovia divaricata at concentrations of 5 mg / ml, 40 mg / ml, and 50 mg / ml showed an inhibitory effect.

[0092] The most significant promoting effects of Achyranthes bidentata aqueous extract on POD enzyme activity in Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml and 20 mg / ml, promoting activity by 18.03 U / g / min and 17.28 U / g / min, respectively. Achyranthes bidentata aqueous extracts at concentrations of 5 mg / ml, 30 mg / ml, 40 mg / ml, and 50 mg / ml showed inhibitory effects, with the 50 mg / ml extract exhibiting the most significant inhibitory effect.

[0093] from Figure 8It can be seen that, compared with the control group, the aqueous extract of Platycodon grandiflorus has a certain inhibitory effect on the CAT enzyme activity of Platycodon grandiflorus seedlings. The aqueous extract of Glehnia littoralis has the most significant promoting effect on the CAT enzyme activity of Platycodon grandiflorus seedlings at 20 mg / ml and 30 mg / ml, with the highest being 30 mg / ml, promoting it by 54.49 U / g / min; the aqueous extracts of Glehnia littoralis at 5 mg / ml, 10 mg / ml, 40 mg / ml and 50 mg / ml show an inhibitory effect.

[0094] The effects of 5 mg / ml, 10 mg / ml, 20 mg / ml and 30 mg / ml aqueous extracts of Saposhnikovia divaricata on the CAT enzyme activity of Platycodon grandiflorus seedlings were not significant, while the 40 mg / ml and 50 mg / ml aqueous extracts of Saposhnikovia divaricata showed an inhibitory effect.

[0095] The most significant promoting effects of Achyranthes bidentata aqueous extract on CAT enzyme activity in Platycodon grandiflorus seedlings were observed at concentrations of 10 mg / ml and 20 mg / ml, which increased activity by 119.02 U / g / min and 132.68 U / g / min, respectively. Achyranthes bidentata aqueous extracts at concentrations of 5 mg / ml, 30 mg / ml, 40 mg / ml, and 50 mg / ml showed inhibitory effects.

[0096] In summary, after allelopathic treatment, North American ginseng, Achyranthes bidentata, and Saposhnikovia divaricata all promote the germination and growth of Platycodon grandiflorus and are all suitable for intercropping with Platycodon grandiflorus. Among them, North American ginseng has the most obvious effect, followed by Achyranthes bidentata and Saposhnikovia divaricata. During the allelopathic treatment, the optimal concentration of Achyranthes bidentata water extract is 10-20 mg / ml; the optimal concentration of Saposhnikovia divaricata water extract is 10-30 mg / ml; and the optimal concentration of North American ginseng water extract is 20-30 mg / ml. When the concentration of the water extracts of the above Chinese medicinal materials reaches 50 mg / ml, they all uniformly show an inhibitory effect on the germination and growth of Platycodon grandiflorus.

Claims

1. An application of a method for regulating the germination and growth of Platycodon grandiflorus using allelopathic effects among medicinal herbs, characterized in that, Platycodon grandiflorus seeds treated with an aqueous extract of Adenophora stricta were intercropped with Adenophora stricta seeds; the concentration of the aqueous extract of Adenophora stricta was 20-30 mg / ml. The method for treating Platycodon grandiflorus seeds with water extract of Glehnia littoralis includes the following steps: S1. Pretreatment of Platycodon grandiflorus seeds: Select plump, healthy, and disease-free Platycodon grandiflorus seeds, disinfect them with 0.1% potassium permanganate for 4-6 minutes, and then rinse them with distilled water 3-4 times. S2. Add the North American ginseng water extract to the Platycodon grandiflorus seeds treated in step S1, ensuring that the liquid level of the North American ginseng water extract completely covers the Platycodon grandiflorus seeds. Then add an equal volume of distilled water and soak for 20-28 hours.

2. The application as described in claim 1, characterized in that, The preparation method of the North American ginseng water extract is as follows: the root of North American ginseng is cut into small sections of 1.5-2.5 cm in length, crushed, passed through a 50-70 mesh sieve, and water is added to prepare a North American ginseng water extract with a concentration of 90-110 mg / ml. Then, it is ultrasonically treated on an ultrasonic processor for 2.5-3.5 h, and then allowed to stand at low temperature for 40-55 h. After filtration, it is diluted with distilled water to the required concentration to prepare the North American ginseng water extract. The intensity of the ultrasonic treatment is 150-250 W and the frequency is 30-50 kHz.

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