A kind of Penicillium galactifolium GF3 and its application
By isolating and screening the P. ash GF3 from the rhizosphere soil of tea root rot infection, and conducting relevant research, the problem of preventing and treating tea root rot is solved, and effective inhibition of tea root rot pathogens and promoting tea tree growth is achieved.
Patent Information
- Application Number
- CN202410011834.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-04
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2044-01-04
AI Technical Summary
Tea tree root rot is widely present in tea gardens, causing the root system of tea tree and the withering of the crown. In severe cases, it causes large-scale death in tea gardens, causing economic losses to tea production and hindering the development of the tea industry.
Penicillium cremeogriseum GF3 (Penicilliumcremeogriseum GF3) was isolated and screened from the rhizosphere soil of tea root rot infection, and the growth characteristics, antibiotic effects, antibacterial spectrum determination, bioavailability and hydrolase activity determination were carried out to clarify its biodefense potential.
P. milk ash GF3 has a significant inhibitory effect on the pathogens of tea tree root rot, with a bacteriostatic rate of 75.23%. It has the ability to decompose organophosphorus and inorganic phosphorus, decompose potassium, iron-producing carriers, nitrogen fixation, ammonia and IAA. It can promote the growth of tea trees and provide new biological control methods.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of harmful microorganism prevention and control, and more specifically to Penicillium foetidum GF3 and its application. Background Art
[0002] There are many types of root diseases of tea trees, mainly tea seedling white rot, tea seedling root knot nematode disease, tea purple feather disease, tea red root rot, tea brown root rot, etc. In previous studies, we reported a pathogen Fusarium cugenangense that causes tea tree root rot, which belongs to a specific strain of Fusarium oxysporum species complex (FOS C). The pathogen parasitizes in the rhizosphere soil of tea trees and accumulates in the soil of tea gardens for a long time. It is highly infectious and can cause root or crown rot and vascular wilt of tea trees. In severe cases, it can cause large-scale death of tea trees in patches or the entire tea garden, causing serious economic losses to tea production and seriously hindering the development of the tea industry.
[0003] Microbial agents have been listed as key products for the development of the national bio-industry. At the national macro level, national demands such as "reducing weight and medicine consumption", "zero growth in fertilizers", "sustainable agricultural development" and "ecological agriculture" are inseparable from the development of microbial agents. "Using bacteria to inhibit bacteria" is considered an ideal way to prevent and control plant diseases, but the basis for the development of microbial agents is the resources of microbial strains with good antagonistic effects. Therefore, it is of great practical significance to explore, screen and expand new functional strains, and to select strains with good tea tree affinity, regionality, pertinence, adaptability and productivity for the prevention and control of tea tree root rot pathogens.
[0004] Therefore, how to screen a biocontrol strain for tea tree root rot is a problem that technicians in this field need to solve urgently. Summary of the invention
[0005] One of the purposes of the present invention is Penicillium cremeogriseum GF3, which was deposited in the China Center for Type Culture Collection on September 26, 2023, with a deposit number of CCTCC NO: M20231796, a deposit address of China. Wuhan. University, and a classification name of Penicillium cremeogriseum GF3.
[0006] Another object of the present invention is to provide the use of the fermentation stock solution, bacterial suspension, and low-volatile metabolites of Penicillium galactifolia GF3 in inhibiting tea tree root rot pathogens.
[0007] Another object of the present invention is to provide the use of the described Penicillium GF3 in inhibiting other plant pathogens, which include: tobacco root rot pathogens, eggplant brown streak pathogens, potato early blight pathogens, wild rice root rot pathogens, corn leaf blight pathogens, citrus bark disease pathogens, pepper wilt pathogens, Polygonatum anthracnose pathogens, wild rice root rot pathogens and strawberry blight pathogens.
[0008] Another object of the present invention is to provide the application of Penicillium galactifolia GF3 in promoting plant growth.
[0009] In the above applications, Penicillium galactifolia GF3 has the ability to decompose organic phosphorus and inorganic phosphorus, release potassium, produce iron carriers, fix nitrogen, produce ammonia and produce IAA.
[0010] It can be seen from the above technical scheme that compared with the prior art, the present invention takes the tea tree root rot pathogen as the target bacteria, isolates and screens a Penicillium cremeogriseum strain GF3 from the rhizosphere soil infected with tea tree root rot, and conducts research on its growth characteristics, antibiotic effects, antibacterial spectrum, growth-promoting ability and hydrolase activity, aiming to clarify its biocontrol potential in order to provide new bacterial species resources for the biological control of tea tree root rot. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.
[0012] Figure 1 The attached figure shows the plate inhibition effect of strain GF3 on tea tree root rot pathogens; A. treatment group B. control;
[0013] Figure 2 The attached figures are the colonies and microscopic features of strain GF3; A. morphology of the front and back of PDA medium; C, D. morphology of the front and back of CYA medium; EF. morphology of hyphae and spores;
[0014] Figure 3 The accompanying figure is a phylogenetic tree diagram of strain GF3 constructed based on BenA sequence;
[0015] Figure 4 The attached figure shows the effect of strain GF3 on the mycelial growth of tea root rot pathogens; A. control; B, C: treatment;
[0016] Figure 5 The accompanying drawing is a study on the growth characteristics of strain GF3;
[0017] Figure 6 The attached figure is a growth-promoting ability test diagram of strain GF3; A. β-1, 3 glucanase; B. ability to degrade inorganic phosphorus; C. ability to degrade organic phosphorus; D. ability to degrade potassium; E. ability to produce iron carriers; F. ability to fix nitrogen; G. ability to produce IAA; H. ability to produce ammonia. DETAILED DESCRIPTION
[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0019] Test materials in the examples: tea root rot pathogen Fusarium cugenangense, a specific strain belonging to the Fusarium oxysporum species complex (FOSC), was isolated and preserved by our laboratory. Test soil was collected from the rhizosphere soil of tea trees infected with root rot pathogens at the Chang'an Tea Science Teaching Base of Hunan Agricultural University.
[0020] Example 1 Isolation and screening of antagonistic strains
[0021] Antagonistic fungi were screened using the gradient dilution plate spreading method. 1 g of soil sample was placed in a 25 mL Erlenmeyer flask filled with 9 mL of sterile water to prepare a soil suspension stock solution. The stock solution was placed in a shaker at 28°C and 180 r / min for 30 min, and then the soil stock solution was diluted to 10 -1 ~10 -7 100 μL of each gradient was spread on a PDA medium plate, and each dilution gradient was repeated 3 times. The plate was inverted and cultured in a 25°C incubator for 7 days. After colonies grew on the plate, individual fungal colonies were picked for purification and preservation.
[0022] Antagonistic bacteria were screened for isolated fungi by plate confrontation method. Tea root rot pathogens were used as target bacteria, and isolated fungi were screened by plate confrontation method. Use a hole puncher to punch holes at the edges of the purified rhizosphere fungi and pathogens to obtain a 5mm diameter fungus cake. The pathogen cake was inoculated into the center of a 75mm diameter PDA culture dish, and the rhizosphere fungus cake was inoculated at two symmetrical points 20mm away from the pathogen cake. Only the pathogen was inoculated as the control, and 3 replicates were set for each treatment. Inverted culture was placed at 25℃ in the dark for 7 days, and the antibacterial rate of each strain was calculated.
[0023] Inhibition rate (%) = [(control colony diameter - treated colony diameter) / control colony diameter] × 100%
[0024] A total of 38 fungal strains were isolated by the dilution coating method. The isolated fungi were subjected to a plate confrontation test with the tea root rot pathogens, and 5 antagonistic fungi with antibacterial effects on the tea root rot pathogens were screened out. This patent selected a strain of antagonistic fungi GF3 ( Figure 1 ), the diameter of the pathogen colony after strain GF3 antagonized tea root rot pathogens was 17.33 mm, and the inhibition rate reached 75.23% (Table 1), indicating that the antagonistic bacteria GF3 had a good antagonistic effect on tea root rot pathogens. Therefore, this patent selected strain GF3 for subsequent research.
[0025] Table 1 Inhibitory effect of strain GF3 on mycelium of tea root rot pathogens
[0026]
[0027] Example 2 Identification of strain GF3
[0028] Morphological identification
[0029] After 7 days of culture on PDA, the colony diameter of the strain was 46.80 mm, and the morphology was a regular circle with neat edges. The aerial hyphae were not well developed. The front of the colony was white at first, and then turned gray-green. The gray-green color in the center of the colony gradually expanded to the edge, showing a ribbed pattern. The back of the colony was light yellowish brown ( Figure 2 A); After 7 days of culture on CYA medium, the strain had deep radial grooves, an umbilical protrusion in the center, complete edges, velvety texture, and the entire colony was white ( Figure 2 B). Microscopic observation showed that the vegetative mycelium was transparent and had transverse septa; the spore-producing structure consisted of stipes, twigs, and peduncle bases; the conidiophores grew vertically from the mycelium, were tight and smooth, and the spore-producing structure was broom-shaped and arranged in two or more whorls. The spores were small oval particles connected in chains. Based on the above colony culture growth morphological characteristics and the comparison with the "Handbook of Fungal Identification", it was preliminarily identified as Penicillium cremeogriseum ( Figure 2 CE)
[0030] Physiological and biochemical characteristics
[0031] The results of physiological and biochemical tests showed that the strain GF3 was positive for VP test, Gelatin liquefaction test, Hydrogenperoxidase test, Arginine decarboxylase test, and methyl red test MR, hydrogen sulfide production H 2Sproduction was negative; the strain was able to decompose glucose, lactose, maltose, fructose, sucrose, and mannitol (Table 2).
[0032] Molecular Biology Identification
[0033] The BenA sequence of strain GF3 is 530 bp long. The sequence was uploaded to the GenBank database for homology comparison, and it was found that the similarity between strain GF3 and Penicillium cremeogriseum was 99%. The strain BenA sequences with higher similarity were selected to construct a phylogenetic tree ( Figure 3 ). Combining the morphological characteristics and molecular biological identification results, the strain GF3 was finally determined to be Penicillium cremeogriseum, which was deposited in the China Center for Type Culture Collection on September 26, 2023, with the deposit number CCTCC NO: M20231796, and the deposit address is Wuhan University, China, and the classification name is Penicillium cremeogriseum GF3.
[0034] Table 2 Physiological and biochemical characteristics of strain GF3
[0035] Measurement items result Measurement items result Methyl red test - glucose + Acetyl methyl test + lactose + Gelatin liquefaction + maltose + Catalase + fructose + Arginine decarboxylase + sucrose + Hydrogen sulfide production - Mannitol +
[0036] Note: +: positive; -: negative.
[0037] Example 3 Effect of strain GF3 on mycelium
[0038] The mycelium morphology of the tea tree root rot pathogen was observed under an optical microscope. The mycelium of the control group had a complete structure, uniform thickness, smoothness, neat growth, and was slender without swelling or breakage ( Figure 4 A); however, the mycelium of the tea root rot pathogen in the treatment group grew abnormally, with the mycelium of strain GF3 entangled with the mycelium of the pathogen and the mycelium of the pathogen entangled with each other ( Figure 4 B, C), indicating that strain GF3 can achieve the antibacterial effect by affecting the hyphae growth of tea root rot pathogens.
[0039] Example 4 Study on the growth characteristics of strain GF3
[0040] Effect of different carbon sources on mycelial growth: The mycelial growth rates of strain GF3 in medium containing fructose, sucrose, maltose, lactose and glucose were 5.34 mm / d, 5.17 mm / d, 5.24 mm / d, 4.80 mm / d and 3.73 mm / d, respectively. Compared with the five carbon sources, it grew fastest on the medium containing fructose and slowest on the medium containing glucose ( Figure 5 A);
[0041] Effects of different nitrogen sources on mycelial growth: The mycelial growth rates of strain GF3 in the culture medium containing potassium nitrate, yeast extract, ammonium sulfate, peptone and sodium nitrate were 2.74 mm / d, 5.13 mm / d, 2.44 mm / d, 3.73 mm / d and 2.21 mm / d, respectively. Compared with the five nitrogen sources, its growth rate in the culture medium containing yeast extract was significantly higher than that in the culture medium containing other nitrogen sources ( Figure 5 B);
[0042] Effect of different carbon-nitrogen ratios on mycelial growth: The growth rates of the strain in the basic medium with carbon-nitrogen ratios of 20:1, 40 / 1, 60 / 1 and 80 / 1 were 4.91 mm / d, 4.28 mm / d, 4.18 mm / d and 4.16 mm / d, respectively. There was no significant difference in the carbon-nitrogen ratio on the mycelial growth rate of strain GF3 ( Figure 5 C);
[0043] Effects of different metal ions on mycelial growth: strains in the presence of Na + , Mn 2+ , K + , Fe + and Mg + The growth rates in the metal ion medium were 4.58 mm / d, 6.46 mm / d, 4.52 mm / d, 4.22 mm / d and 3.73 mm / d, respectively. 2+ The fastest growth was in sulfate medium ( Figure 5 D).
[0044] Effect of different pH on mycelial growth of strain GF3: The effect of pH on mycelial growth rate of strain GF3 was not very different. Its growth rate was 11.67-14.69 mm / d at pH 5.0-12. It grew fastest at pH 8.0, which was 14.69 mm / d, and slowest at pH 5.0, which was 11.67 mm / d. Figure 5 E).
[0045] Effect of different NaCl concentrations on mycelial growth of strain GF3: NaCl has a significant effect on the mycelial growth rate of strain GF3. When the NaCl concentration is 0%, the mycelial growth is the fastest, with a growth rate of 13.21 mm / d. As the NaCl concentration increases, the mycelial growth rate is significantly inhibited. When the NaCl concentration is 11%, the growth rate is 1.40 mm / d. When the NaCl concentration is 12%, the strain does not grow at all, indicating that the strain has a certain salt tolerance ( Figure 5 F).
[0046] Example 4 Study on the antagonistic effect of strain GF3
[0047] Inhibitory effect of fermentation products on tea root rot pathogens: refer to the method of Zhang Yongzhi et al. and make some improvements. Take ten bacterial cakes and put them into 200mL PDB medium, culture at 180r / min and 28℃ for 7d to obtain fermentation liquid. Centrifuge the fermentation liquid at 12000r / min and filter with 0.22um sterile microporous filter membrane to obtain sterile fermentation filtrate. Wash the precipitate after centrifugation three times with sterile water, and then mix the washed precipitate with an equal amount of sterile water to obtain bacterial suspension. The fermentation liquid and bacterial suspension are prepared by filter paper method, and the sterile fermentation filtrate is prepared by mixed plate method. A 5mm pathogenic bacteria cake is inoculated in the center of a PDA plate, and a 5mm antagonistic bacteria cake is inoculated in the center of another PDA plate. The two plates are buckled and sealed, and cultured in a 25℃ incubator for 7d. The fermentation liquid, bacterial suspension and sterile fermentation filtrate of strain GF3 are measured.
[18] Inhibitory effect on pathogens.
[0048] Inhibitory effect of volatile metabolites on tea root rot pathogens: Use a hole puncher to take a 5 mm diameter antagonistic bacteria cake and inoculate it in the center of a PDA plate. Take a tea root rot pathogen cake of the same size and inoculate it in the center of another PDA plate. Put the two inoculated plates together and culture them in the dark at 25℃ for 7 days. Put the PDA plate inoculated with pathogens on top of the pure PDA plate not inoculated with pathogens as a control. Each treatment was repeated 3 times to observe the growth of pathogen hyphae. The colony diameter of the pathogen was measured by the cross method and the inhibition rate was calculated.
[0049] Inhibitory effect of non-volatile metabolites on tea root rot pathogens: Sterilized double-layer glass paper was spread in the center of the poured PDA, and a 5mm diameter antagonistic bacterial cake was taken with a hole puncher and inserted into the center of the filter membrane. After culturing at 25℃ in the dark for 7 days, the filter membrane and the antagonistic bacterial hyphae were gently removed with tweezers, and a 5mm diameter pathogenic bacterial block was inoculated in the original position, and cultured at 25℃ in the dark for 7 days. Only the pathogenic bacterial block was inoculated on the new PDA plate as a control. Three replicates were set for each treatment to observe the colony growth, and the colony diameter of the pathogen was measured by the cross method to calculate the inhibition rate.
[0050] The inhibitory effect of fermentation products on tea root rot pathogens: After 7 days of confrontation culture, the inhibition rate of the fermentation solution of strain GF3 on tea root rot pathogens was 70.52%; the inhibition rate of the bacterial suspension on tea root rot pathogens was 68.66%; the inhibition rate of the sterile fermentation filtrate on tea root rot pathogens was 28.61%; the inhibition rate of the fermentation solution group on the growth of pathogens was significantly higher than that of other components. It can be seen that the fermentation solution of strain GF3 has the strongest antibacterial activity, the bacterial body has a strong inhibition rate on pathogens, and the antibacterial activity of the sterile fermentation filtrate on pathogens is relatively weak;
[0051] Inhibitory effect of volatile metabolites on tea root rot pathogens: After 5 days of flat plate culture, the inhibition rate of volatile metabolites of strain GF3 on pathogens was 26.85%.
[0052] Inhibitory effect of the hardly volatile metabolites on tea root rot pathogens: The inhibition rate of the hardly volatile metabolites of strain GF3 on pathogens was 63.92% (Table 3).
[0053] Table 3 Inhibitory effects of different metabolites of strain GF3 on tea root rot pathogens
[0054] Antibacterial substance type Colony diameter (cm) Antibacterial rate (%) Fermentation liquid 2.06±0.07b 70.52±1.12a bacterial suspension 2.19±0.08b 68.66±1.14a Sterile fermentation filtrate 4.99±0.10a 28.61±1.45b Low volatile metabolites 2.31±0.09b 63.92±1.49b Volatile metabolites 5.12±0.17a 26.85±2.51b
[0055] Example 5 Determination of the antibacterial spectrum of strain GF3
[0056] The plate confrontation method was used to determine the antibacterial spectrum of the antagonistic strain. The activated cakes of 9 plant pathogens, including tobacco root rot pathogen F.oxysporum, brown streak pathogen P.vexans, potato early blight pathogen A.alternate, wild rice root rot pathogen F.oxysporum, corn leaf blight pathogen E.turcicum, citrus sand bark pathogen D.citri, pepper wilt pathogen F.oxysporum, polygonatum anthracnose pathogen C.circinans, wild rice root rot pathogen F.oxysporum, strawberry blight pathogen P.fragariae, were inoculated into the center of the PDA plate. The activated antagonistic bacteria cakes were inoculated at two symmetrical points 20 mm away from the pathogens for plate confrontation. The inhibitory effect of strain GF3 on the above 9 pathogens was determined. The inoculation of each pathogen alone was used as the control. Each treatment was repeated 3 times. After culturing in a constant temperature box at 25℃ for 7 days, the diameter of the inhibition zone was measured and the inhibition rate was calculated.
[0057] The results of the antimicrobial spectrum determination test showed that strain GF3 had obvious inhibitory effects on nine plant pathogens, including tobacco root rot F.oxysporum, eggplant brown streak pathogen P.vexans, potato early blight pathogen A.alternate, wild rice root rot pathogen F.ox ysporum, corn leaf blight pathogen E.turcicum, citrus sand bark pathogen D.citri, pepper wilt pathogen F.oxysporum, polygonatum anthracnose pathogen C.circinans, wild rice root rot pathogen F.oxysporum, and strawberry blight pathogen P.fragariae, with inhibition rates of 80.14%, 81.23%, 74.33%, 76.99%, 71.38%, 71.66%, 75.95%, 76.76%, and 80.56%, respectively, indicating that the antagonistic strain has good antagonistic effect and has a broad-spectrum antibacterial activity (Table 4).
[0058] Table 4 Inhibitory effect of strain GF3 on 9 plant pathogens
[0059] Pathogens Colony diameter (cm) Antibacterial rate (%) Tobacco root rot pathogen 1.39±0.02d 80.14±0.29a Eggplant brown streak pathogen 1.31±0.03d 81.23±0.37a Potato early blight pathogen 1.80±0.03c 74.33±0.46c Zizania root rot pathogen 1.61±0.06c 76.99±0.86b Corn leaf blight pathogen 2.00±0.01a 71.38±0.19d Citrus scurf disease 1.98±0.12a 71.66±1.67d Fusarium wilt 1.68±0.07bc 75.95±0.98bc Polygonatum anthracnose pathogen 1.63±0.07bc 76.76±0.95bc Strawberry blight pathogen 1.36±0.09d 80.56±1.28a
[0060] Note: The data in the table are mean ± standard error, and different lowercase letters indicate significant differences (P<0.05).
[0061] Example 6 Determination of the disease prevention and growth-promoting ability of strain GF3
[0062] The strain GF3 was subjected to partial cell wall degrading enzyme activity detection and partial qualitative detection of growth-promoting ability, including cellulase activity, β-1,3 glucanase activity, protease activity, amylase activity, organic phosphorus decomposition ability, chitinase activity, inorganic phosphorus decomposition ability, potassium decomposition ability, nitrogen fixation ability, siderophore production ability, IAA production ability and ammonia production ability detection.
[0063] The strain GF3 produced a transparent circle on the β-1,3 glucanase test plate, indicating that the strain had the ability to decompose β-1,3 glucanase, while there was no transparent circle on the cellulase, amylase, protease and chitinase test plates, indicating that the strain had insufficient cellulase, amylase, protease and chitinase abilities ( Figure 6 A); the strain produced transparent circles when grown on the organic phosphorus and inorganic phosphorus detection plates and the potassium dissolving detection plates, indicating that the strain has the ability to decompose organic phosphorus and inorganic phosphorus and the ability to dissolve potassium ( Figure 6 BD); the strain produced a red-purple halo when grown on the CAS double-layer medium, indicating that the strain has the ability to produce siderophores ( Figure 6 E); the strain can still grow after being transferred to nitrogen-free medium for 5 times, indicating that the strain has the ability to fix nitrogen ( Figure 6 F); Using IAA standard solution as positive control, sterile water as blank control, and no tryptophan as negative control, after the Salkowski colorimetric test, the color of the treated liquid turned red, indicating that the strain has the ability to produce IAA ( Figure 6 G); using the uninoculated culture medium as the control, Nessler's reagent was added to the control and bacterial supernatant, and the supernatant turned orange-yellow, indicating that strain GF3 has the ability to produce ammonia ( Figure 6 H, Table 5).
[0064] Table 5 Growth-promoting ability test of strain GF3
[0065] Growth-promoting ability test result Growth-promoting ability test result Cellulase - Ability to decompose organic phosphorus + β-1,3-Glucanase + Potassium-dissolving capacity + Amylase - Siderophore production capacity + Protease - Nitrogen fixation capacity + Chitinase - Ammonia production capacity + Ability to decompose inorganic phosphorus + IAA production capacity +
[0066] Example 7 Potted Plant Protection Test Evaluation
[0067] A two-year-old susceptible tea variety Quercus chinensis was selected as the test material, and a surfactant was added to the antagonistic bacteria fermentation liquid and mixed for later use. Healthy tea potted plants with the same growth were selected and divided into 4 groups, namely the pathogen fermentation liquid treatment group, the strain GF3 fermentation liquid treatment group, the 10-fold strain GF3 fermentation liquid treatment group, and the 50-fold strain GF3 fermentation liquid treatment group. The specific operations were as follows: 20 mL of pathogen fermentation liquid was used to irrigate the roots of all 4 groups of tea seedlings; after 1 day of pathogen fermentation liquid treatment, 20 mL of strain GF3 fermentation liquid, 10-fold strain GF3 fermentation liquid, and 50-fold strain GF3 fermentation liquid were used to irrigate the roots of 3 groups of tea seedlings. The above operation was repeated once on the 14th day, and each treatment was repeated for 4 groups, with 4 potted plants in each group, a total of 64 potted plants, which were cultured under natural conditions to observe their disease status. After 28 days, the incidence rate survey and prevention and control effect evaluation were carried out. The incidence rate and control effect were calculated according to the following formulas:
[0068] Incidence rate (%) = (number of diseased plants / total number of plants) × 100%
[0069] Control effect (%) = (control incidence - treatment incidence) / control incidence × 100%
[0070] Table 6 Evaluation of potted plant protection effect test
[0071] deal with Incidence (%) Control effect (%) Pathogen fermentation broth 93.75％ — Strain GF3 fermentation stock solution 25.00％ 73.33％ 10 times strain GF3 fermentation broth 50.00％ 46.67％ 50 times strain GF3 fermentation broth 56.25％ 40.00％
[0072] The results of the potted plant prevention test showed (Table 6) that 28 days after the inoculation of the pathogen, the incidence rate of the pathogen fermentation liquid group was 93.75%, the incidence rate of tea seedling root rot in the groups treated with strain GF3 fermentation liquid, 10 times strain GF3 fermentation liquid and 50 times strain GF3 fermentation liquid were 25.00%, 50.00% and 56.25%, respectively, and the prevention and control effects of tea seedling root rot were 73.33%, 46.67% and 40.00%, respectively. The fermentation liquid had the best prevention and control effect. Strain GF3 has great application potential in the prevention and control of tea tree root rot.
[0073] Evaluation of growth promotion effect
[0074] A two-year-old susceptible tea variety, Quercus chinensis, was selected as the test material, and a surfactant was added to the antagonistic bacteria fermentation liquid and mixed for use. Healthy tea potted plants with the same growth were selected and divided into 4 groups, namely, a control group treated with clean water, a group treated with the original fermentation liquid of strain GF3, a group treated with 10 times the fermentation liquid of strain GF3, and a group treated with 50 times the fermentation liquid of strain GF3. The specific operation was as follows: 20 mL of clean water, the original fermentation liquid of strain GF3, 10 times the fermentation liquid of strain GF3, and 50 times the fermentation liquid of strain GF3 were used to irrigate the tea seedlings with roots, and the treatment was repeated once on the 14th day. Each treatment was repeated in 4 groups, with 4 potted plants in each group, for a total of 64 potted plants, which were cultured under natural conditions, and the plant height was measured at 0d and 28d to analyze the changes in plant height. See Table 7.
[0075] Table 7 Evaluation of growth promotion effect
[0076]
[0077]
[0078] The results showed that compared with the control group, the average plant height increases of tea seedlings treated with fermentation solution of strain GF3, 10 times fermentation solution of strain GF3, and 50 times fermentation solution of strain GF3 were 0.28cm, 1.51cm, 1.11cm and 0.93cm respectively. The fermentation solution had the best growth-promoting effect, indicating that strain GF3 can promote the growth of tea trees.
[0079] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0080] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one 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. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A Penicillium galactifolium GF3, characterized in that: Penicillium cremeogriseum GF3 was deposited in the China Center for Type Culture Collection on September 26, 2023, with the deposit number CCTCC NO: M20231796.
2. Use of the fermentation stock solution and bacterial suspension of Penicillium galactorum GF3 according to claim 1 in inhibiting tea tree root rot pathogens.
3. Use of the Penicillium galactifolium GF3 according to claim 1 in inhibiting plant pathogens, wherein the plant pathogens include: Tobacco root rot pathogens, eggplant brown streak pathogens, potato early blight pathogens, wild rice root rot pathogens, corn leaf blight pathogens, citrus bark disease pathogens, pepper wilt pathogens, Polygonatum anthracnose pathogens and strawberry blight pathogens.
4. Use of Penicillium galactifolium GF3 according to claim 1 in plant growth promotion.