CN107236689B - A strain of Pseudomonas fluorescens pf27 and its application in plant growth promotion - Google Patents

Abstract

The invention discloses a strain of Pseudomonas fluorescens pf27 and its application in plant growth promotion. The invention provides a strain of Pseudomonas fluorescens pf27, and prepares a microbial agent pf27. Experiments have shown that the plant height and root length of plants are significantly improved after the microbial agent pf27 treatment, and it has a certain growth-promoting effect on the plants. Up to 829.14%, it has a broad-spectrum and high-efficiency role in promoting plant growth, especially can promote the growth of Solanaceae vegetable crops and improve their quality. The invention solves the problems of poor effect or residues of other methods such as chemical fertilizers, and helps to promote the sustainable development of agriculture, and has a good application prospect.

Description

A strain of Pseudomonas fluorescens pf27 and its application in plant growth promotion

technical field

The invention belongs to the field of biotechnology, and in particular relates to a strain of Pseudomonas fluorescens pf27 and its application in plant growth promotion.

Background technique

The continuous cropping obstacles brought about by intensive production have seriously affected a series of problems such as crop yield and quality, plant physiological characteristics and soil microbial community structure, and rampant plant diseases and insect pests, seriously affecting the planting efficiency and healthy development of agriculture. The large-scale excessive application of chemical fertilizers has caused great harm to the environment and human health, and has become an important factor affecting the environment, human health and social development. In recent years, due to the large-scale production and unrestricted use of chemical pesticides and chemical fertilizers, they have caused pollution to human living environment and agricultural, forestry and animal husbandry products, endangered human and animal health, water and soil and other environmental resources, and restricted the sustainable development of agricultural production. It has become one of the serious social problems at present. Therefore, the use of beneficial microorganisms in the agricultural ecosystem to prevent and control plant pests and diseases, improve crop growth and increase crop yield has increasingly become a research hotspot. The growth and development of plants are closely related to the microorganisms in the surrounding environment, and the growth potential of plants often depends on the interaction results between plants and microorganisms. In the plant-microbe system, microorganisms are associated with both the above-ground parts of plants (such as leaf circumference) and the underground parts, thereby affecting the soil structure, the availability of nutrients in the soil and the production of some beneficial or harmful plants. metabolite.

Excessive application of several chemical fertilizers of a single nature can easily lead to nutritional imbalance of crops. Most of the chemical fertilizers contain various salts. Among them, nitrogen, phosphorus, potassium and other chemical substances are easily consolidated by the soil and accumulate in the soil. Soil salinization causes soil nutrient imbalance, which affects and hinders the transformation and absorption of absorbed nutrients by crops, resulting in poor growth of fruits and vegetables, poor taste and quality of crops, and reduced quality. Not sweet, bad taste, and perishable, not suitable for storage. A class of microorganisms in the soil, such as Pseudomonas fluorescens, Trichoderma, Bacillus, etc., can improve plant growth conditions by means of their metabolic processes or metabolites, such as increasing nutrients, secreting hormones, stimulating plant root development, etc., inducing plants to produce plant diseases. Defensive response to root rot diseases such as late blight and Fusarium. The secondary metabolites produced by microorganisms contain substances that stimulate the growth and development of plants. The community dynamics of Pseudomonas fluorescens in the potato rhizosphere and the number of dominant strains and their effects on potato growth provide the basis and basis for the application of the effect of promoting plant growth obtained in greenhouse experiments to the field. The polymers produced by microorganisms have the ability to resist drought, reduce water stress, improve soil structure, supply plant organic nutrients and regulate ionic activity. During their life activities, microorganisms can dissolve mineral elements in the soil that are difficult for plants to use and convert them into It becomes a substance that promotes activity, thereby helping plants absorb various mineral elements. There are many potassium bacteria and phosphorus bacteria in the soil, which can release potassium and phosphorus in invalid state of soil minerals for plant growth and development. Microorganisms can promote the formation of humic acid in the organic matter around the root system, provide plants with stress resistance, degrade pollutants in the soil, reduce the toxicity to plants, increase the content of humic acid in the soil, and promote plant growth and development. Therefore, there is an urgent need for safer and more effective alternative products. In recent years, microbial preparations have attracted much attention due to their environmental friendliness, production promotion, and disease prevention. The use of beneficial microorganisms in soil to develop microbial fertilizers has become a research hotspot in recent years.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a strain of Pseudomonas fluorescens pf27.

The deposit number of Pseudomonas fluorescens pf27 provided by the present invention is CGMCC No. 14105.

The classification name of Pseudomonas fluorescens pf27 of the present invention is Pseudomonas fluorescens, and the strain has been deposited in the General Microorganism Center of the China Microorganism Culture Collection Management Committee (abbreviated as CGMCC, address) on May 8, 2017. : No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, zip code 100101), the deposit number is CGMCC No.14105.

Another object of the present invention is to provide a new use of Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or a bacterial agent containing the same.

The present invention provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or a fungicide containing the same in promoting plant growth.

The present invention also provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or its inoculum in preparing a product for promoting plant growth.

The present invention also provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or its inoculum in increasing plant fresh weight and/or fresh weight biomass.

The present invention also provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or its inoculum in preparing a product for increasing plant fresh weight and/or fresh weight biomass.

The present invention also provides Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or its inoculum in improving plant height and/or stem thickness and/or root number and/or leaves Application in number and/or leaf area and/or maximum leaf growth height.

The present invention also provides Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermentation product or its inoculum in preparation for improving plant height and/or stem thickness and/or root number and/or Application in products of number of leaves and/or leaf area and/or maximum leaf growth height.

In the above application, the Pseudomonas fluorescens may specifically be Pseudomonas fluorescens pf27.

Yet another object of the present invention is to provide a product.

The active ingredient of the product provided by the present invention is the above-mentioned Pseudomonas fluorescenspf27 or its bacterial suspension or its culture solution or its fermentation product or its inoculum;

Described product has following 1)-3) in any function:

1) Promote plant growth;

2) increasing plant fresh weight and/or fresh weight biomass;

3) Increase plant height and/or stem thickness and/or root number and/or leaf number and/or leaf area and/or maximum leaf growth height.

A final object of the present invention is to provide a method for promoting plant growth.

The method for promoting plant growth provided by the present invention comprises the following steps: treating plant seedlings with the above-mentioned Pseudomonas fluorescens pf27 or its inoculum.

In the above method, the concentration of the inoculant for the treatment of plant seedlings is 1×10 ⁵ CFU/mL.

In the above-mentioned application or the above-mentioned product or the above-mentioned method, the specific preparation method of the bacterial agent is as follows: culturing Pseudomonas fluorescens pf27 in a KB medium to obtain a pf27 bacterial liquid, centrifuging the pf27 bacterial liquid, and collecting the precipitate; The precipitation was diluted with sterilized water to a concentration of 1×10 ⁹ -1×10 ¹⁰ CFU/mL to obtain the inoculum.

In the above application or the above product or the above method, the plant is a Solanaceae plant or a Cruciferous plant or a Poaceae plant. The Solanaceae plant can be specifically tomato and potato; the Cruciferous plant can be specifically cabbage, fast vegetables and Chinese cabbage; the Poaceae plant can be specifically wheat and corn.

The present invention screened out Pseudomonas fluorescens pf27 by re-development of existing strains, and prepared the microbial inoculum pf27. Experiments have shown that the plant height and root length of plants are significantly improved after the microbial agent pf27 treatment, and it has a certain growth-promoting effect on the plants. Up to 829.14%, it has a broad-spectrum and high-efficiency role in promoting plant growth, especially can promote the growth of Solanaceae vegetable crops and improve their quality. The invention solves the problems of poor effect or residues of other methods such as chemical fertilizers, and helps to promote the sustainable development of agriculture, and has a good application prospect.

Description of drawings

Figure 1 shows the pf27 phylogenetic tree constructed based on the 16s rDNA sequence.

Figure 2 shows the growth-promoting effect of microbial inoculant pf27 on Solanaceae crop tomato. A. The growth state of the Solanaceae crop Tomato Zhongza No. 9 in the control group on the left, the growth state of the tomato plants treated with pf27 inoculant in the right picture, the picture was taken 21 days after the plant was transplanted; Statistics of plant height and control group data; statistics of total number of leaves of tomato plants treated with C.pf27 inoculum and total number of leaves of control group; statistics of fresh weight of tomato plants under D.pf27 inoculum treatment and fresh weight of control plants; E .Data statistics of tomato plant diameter (stem diameter) and control group plant diameter (stem diameter) under the treatment of pf27 inoculum; statistics of the area of 2 new leaves at the top of the tomato plant under F.pf27 inoculum treatment and data statistics of the control group, all data statistics of plants 33 days after transplanting, n=9, 3 repetitions, Note: * means significant difference at 0.05 level, ** means significant difference at 0.01 level, *** means significant difference at 0.001 level, same as below.

Figure 3 shows the growth-promoting effect of the microbial inoculant pf27 on the Solanaceae crop potato. A. The growth state of the Solanaceae crops in the control group on the left, the growth state of the potato plants under the treatment of pf27 inoculant in the right picture, the pictures were taken 4 weeks after transplanting; Statistics of plant data in the control group; statistics of the total number of leaves of potato plants under the treatment of C.pf27 inoculum and data of the control group; statistics of the number of roots of potato plants under the treatment of D.pf27 inoculum and the number of roots of plants in the control group; under the treatment of E.pf27 inoculum Statistics of root length of potato and control group; comparison of potato production under F.pf27 inoculum treatment and control group; statistics of total weight of potato and control group under G.pf27 treatment, n= 6, 3 repetitions.

Figure 4 shows the growth-promoting effect of microbial inoculant pf27 on cruciferous cabbage. A. The cruciferous cabbage plants in the control group in the left picture, the growth state of the cabbage plants treated with pf27 inoculant in the right picture, the pictures were taken 33 days after plant transplantation; B. The area of the two new leaves at the top of the cabbage plants treated with pf27 inoculation Statistics of plant area in control group, 2 new top leaves per plant; statistics of total number of leaves of cabbage under C.pf27 treatment and control group; fresh weight of cabbage under D.pf27 treatment and fresh weight of control group Statistics; Comparison of the diameter of cabbage plants (stem diameter) under E.pf27 inoculum treatment with that of the control group (stem diameter), n=9, repeated 3 times.

Figure 5 shows the growth-promoting effect of the microbial inoculant pf27 on the cruciferous crop four season green fast food. A. The left picture shows the growth status of the four-season green fast food in the control group, and the right picture shows the growth state of the four-season green fast food under the treatment of pf27 inoculum. The picture was taken 22 days after the plant was transplanted; B. The pf27 inoculant treated four green fast food The statistics of the total number of leaves of the plants in the control group; the fresh weight of the plants under the C.pf27 inoculum treatment and the fresh weight of the plants in the control group; the area of 2 new leaves at the top of the plants under the D.pf27 treatment and the control group Plant area, 2 new apical leaves were counted per plant, n=9, repeated 3 times.

Figure 6 shows the effect of microbial inoculant pf27 on the growth-promoting effect of the cruciferous crop Chinese cabbage. A. The left picture is the growth state of Chinese cabbage Beijing Xin 3 in the control group, the right picture is the growth state of Chinese cabbage plants treated with pf27 inoculant, the picture was taken 22 days after plant transplantation; B. Chinese cabbage treated with pf27 inoculant Statistics with the total number of leaves of the control group; the fresh weight of Chinese cabbage plants treated with C.pf27 inoculum and the fresh weight of the control group; the area of 2 new leaves at the top of Chinese cabbage plants treated with D.pf27 inoculum and the area of the control group, 2 new apical leaves were counted for each plant, n=8, repeated 3 times.

Figure 7 shows the effect of microbial inoculant pf27 on the growth-promoting effect of cruciferous crops. A. The total amount of cabbage plants of cruciferous crops under the treatment of pf27 inoculant in the right picture, the total amount of cabbage plants in the control group in the left picture, n=9; The total amount of control cabbage plants in the left picture, n=9; C. The total amount of cruciferous Chinese cabbage Beijing Xin 3 plants under the treatment of pf27 inoculant in the right picture, the total amount of control cabbage plants in the left picture, n=8; D. Cabbage , Sijiqing fast food and Chinese cabbage Beijing New No. 3 biomass change statistics.

Figure 8 shows the effect of microbial inoculant pf27 on the growth-promoting effect of the grass crop wheat. A. The comparison of the growth status of grass JN17 plants in the control group in the left picture, the growth status of wheat plants under the treatment of pf27 inoculum in the right picture, n=9; Statistics of differences in (Low) and highest height (High), n=9, pictures were taken 27 days after sowing.

Figure 9 shows the effect of the microbial inoculant pf27 on the growth-promoting effect of the grass crop maize. A. The graph on the left is the growth trend of the control group, the Mo17 plant of the Poaceae maize, and the picture on the right is the Mo17 plant of the gramineous maize under the treatment of pf27 inoculant. The pictures were taken 22 days after transplanting, n=9, with 3 repetitions; B. pf27 bacteria Comparison of stem diameters of maize Mo17 plants under C.pf27 inoculum treatment and control group; comparison of stem diameters of maize Mo17 plants under C.pf27 inoculum treatment and control group; Comparison of plant height of maize plants in control group; comparison of stem diameter of maize plants of Poaceae under E.pf27 inoculum treatment and control group.

Preservation Instructions

Species name: Pseudomonas fluorescens

Latin name: Pseudomonas fluorescens

Strain number: pf27

Preservation institution: General Microbiology Center of China Microorganism Culture Collection Management Committee

Abbreviation of depositary institution: CGMCC

Address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing

Deposit date: May 8, 2017

The registration number of the deposit center: CGMCC No.14105

Detailed ways

The experimental methods used in the following examples are conventional methods unless otherwise specified.

The materials, reagents, etc. used in the following examples can be obtained from commercial sources unless otherwise specified.

Quantitative experiments in the following examples are all set up to repeat the experiments three times, and the results are averaged.

The bacterial isolation medium used in the following examples is as follows:

MEA medium: Malt extract 30g, Mycological peptone 5g, agar powder 15g, pH 5.4;

Beef extract peptone medium: peptone 10g, beef extract 3g, sodium chloride 5g, agar powder 12g, water 1000ml, pH 7.2-7.4;

LB medium: sodium chloride 10g, peptone 10g, yeast extract 5g, agar powder 12g, water 1000ml, pH 7.0;

KB medium: peptone 20g, K ₂ HPO ₄ 1.5g, glycerol 8ml, MgSO ₄ 0.74g, H ₂ O supplemented to 1L, pH 7.0; solid medium plus agar powder 12g.

Example 1. Isolation and identification of pf27 strain

1. Isolation of pf27 strain

pf27 was isolated from the rhizosphere soil of the wild rice verruca in Pu'er City, Yunnan Province (latitude 22.33'56" ^, 100.35'12", 737 m above sea level) ^. The specific separation method is as follows: the rhizosphere soil collected from the wild rice area of wart grains, pick the root system, scrape the rhizosphere soil, weigh 5g, put it into the prepared sterilized triangular flask under aseptic conditions, and use sterilized The water gradient was diluted to ^10-6 times, and 3 replicates were set. Take 200 μl of the soil samples from the gradient dilution and spread them on the plates of MEA medium, beef extract peptone medium, LB medium and KB medium, respectively, and cultivate them in incubators at 28°C and 37°C, respectively. Observe the growth state of the colonies every day. The results show that when the dilution is 10 ^-5 and 10 ^-6 times, no colonies grow on the plate, but when the dilution is 10 ^-4 times, a single colony can grow on the plate, and pick and grow on the KB medium. A single colony, named as pf27 strain, was then expanded in KB liquid medium for further strain identification.

2. Identification of pf27 strain

1. Morphological identification of pf27 strain

The pf27 strain can form orange colonies after culturing on KB medium for 24h to 48h. The colonies are round, with smooth surface and raised edges and neat, sticky and easy to pick up.

2. Molecular identification of pf27 strain

The DNA of the pf27 strain was extracted, and PCR amplification was carried out using the universal primers Eubac27F/Eubac1492R to obtain a PCR product containing the conserved region of the 16S rDNA of the pf27 strain. The primer sequences are as follows:

Eubac27F: 5'-AGAGTTTGATCCTGGCTCAG-3';

Eubac1492R: 5'-GGTTACCTTGTTACGACTT-3'.

The PCR product was ligated to pEASY-T3 (purchased from Beijing Quanshijin Biological Co., Ltd.) by TA cloning, and sequenced in Invitrogen with universal primers.

The sequencing results showed that the nucleotide sequence of the PCR product was shown in sequence 1. After blast alignment of the sequenced sequences with the NCBI database, the phylogenetic analysis of pf27 and other Pseudomonas fluorescens strains representing 22 different Pseudomonas species was performed by MEGA5.1 software. The phylogenetic tree is shown in Figure 1. Show.

Based on the above identification results, it is determined that the name of the pf27 strain is Pseudomonas fluorescens, and its classification name is Pseudomonas fluorescens. (CGMCC for short, address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, zip code 100101), and the deposit number is CGMCC No.14105.

Embodiment 2, the preparation of microbial inoculum pf27

The Pseudomonas fluorescens pf27 obtained in Example 1 was shaken cultured in KB medium, shaken at 28°C and cultured at 200rpm for 12-16h, then centrifuged at 4000rpm for 20min, the supernatant was discarded, and the bacterial cell pellet was collected , and then diluted the bacterial cell precipitation with sterilized water to prepare a microbial inoculum ^pf27 (bacterial agent ^pf27 ).

Example 3. The growth-promoting effect of microbial inoculum pf27 on tomato seedlings of Solanaceae crops

1. Experimental method

Tomato seeds of Zhongza No. 9 (produced by Zhongve Seed Industry Technology (Beijing) Co., Ltd.) were sterilized with 3% NaClO solution for 10 minutes, and washed with ddH ₂ O for 6 times to obtain sterilized seeds. Then, the sterilized seeds are spread evenly on the sterilized vermiculite peat soil matrix (vermiculite and peat soil are mixed in a ratio of 1:1, autoclaved at 121°C for 20min) to grow seedlings, and lighted at 26°C for 12h:12h: Cultivate seed germination under dark conditions, when seed germination grows to two true leaves, be transplanted into uniformly adding bacterial agent pf27 (use concentration is that every kg vermiculite peat soil matrix mixture is to add 50ml OD value is the bacterial liquid of 1, The bacterial solution was used in the nutrient hole with a final concentration of 1 × 10 ⁵ CFU/mL) and the control, and the tomato seedlings were transplanted into seedling trays (the diameter of the upper opening of the plug tray was 9 cm, the diameter of the lower opening was 6 cm, and the height was 8 cm). , placed in a greenhouse for growth (conditions: illumination time 12h, temperature 26°C, relative humidity 50%). Continue to cultivate under the above conditions, and transplant 1 seedling in each culture pot, with 27 replicates for each treatment. No inoculum was added as a control (Control). 33 days after transplanting, the plant height, number of leaves, fresh weight of tomato plant, stem thickness of tomato plant, and the area of two new leaves at the top of tomato were counted for each plant, and the biomass increase was calculated. Increase in biomass (%)=(fresh weight of plants in treatment group – fresh weight of plants in control group)/fresh weight of plants in control group×100%.

2. Statistics on the effect of growth promotion

The results are shown in Figure 2. The microbial inoculum pf27 can significantly promote the growth of tomato seedlings. Compared with the control group, the average plant height of tomato plants increased by 18%, the number of leaves increased by 23%, and the plant diameter (stem diameter) after treatment with microbial inoculum pf27. It was 2.5 times that of the control group, while the leaf area increased by as much as 5 times in the pf27 treatment, and the biomass of tomato plants increased by 771.16%.

Embodiment 4. The growth-promoting effect of microbial inoculum pf27 on potato seedlings of Solanaceae crops

1. Experimental method

The potatoes purchased from Beijing Souhang Supermarket were selected and placed in a damp and dark environment. After a week, healthy potato buds with consistent buds were picked and cut off with 70% alcohol sterilized blades. Then the buds were transplanted into plastic flower pots (specification upper opening diameter: 14 cm, lower opening diameter 9.5 cm, height 12.5 cm) uniformly added with bacterial agent pf27 (50ml/Kg, final concentration of bacterial solution at 10 ⁵ CFU/mL) ) and sterilized vermiculite matrix (mixed at a ratio of 1:1, autoclaved at 121°C for 20 minutes), covered with a layer of plastic wrap to keep the surface moisturizing, remove the cotyledons after they grow, and place them in a greenhouse for growth. (Conditions: illumination time 12h, temperature 26°C, relative humidity 50%). Taking no inoculum added as a control (Control), 16 seedlings were treated for each treatment and repeated 3 times. 28 days after transplanting, the plant height, leaf number, root length, root number and potato setting were counted, and the biomass increase was calculated. Increase in biomass (%)=(fresh weight of plants in treatment group – fresh weight of plants in control group)/fresh weight of plants in control group×100%.

2. Statistics on the effect of growth promotion

The results are shown in Figure 3. The microbial agent pf27 can significantly promote the growth of potato seedlings, as shown in the increase of potato plant height by up to 4 times, and the increase of leaf number and root number by 114% and 50%, respectively, compared with the control. In the absence of chemical fertilizers, the potato yield of microbial inoculum pf27 was significantly increased. The statistical results showed that the biomass of microbial inoculum pf27 increased by 1115.15%.

Example 5. Growth-promoting effect of microbial inoculum pf27 on cruciferous crop cabbage

1. Experimental method

According to the experimental method in Example 3, the seeds of the cabbage variety Jingfeng No. 1 (Vegetable and Flower Research Institute, Chinese Academy of Agricultural Sciences) were germinated until 2 true leaves were grown, and the seedlings were transplanted into the nursery plug trays (on the plug tray specifications). The diameter of the mouth is 9 cm, the diameter of the lower mouth is 6 cm, and the height is 8 cm), continue to cultivate under the above conditions, transplant 1 seedling in each culture pot, and repeat 9 times for each treatment, so as not to add any bacteria. agent as a control (Control). 33 days after transplanting, the number of leaves, fresh weight of each plant, stem thickness of cabbage, and the area of 2 new leaves at the top of cabbage were counted, and the increase in biomass was calculated. Increase in biomass (%)=(fresh weight of plants in treatment group – fresh weight of plants in control group)/fresh weight of plants in control group×100%.

2. Statistics on the effect of growth promotion

The results are shown in Figure 4. The microbial inoculum pf27 can significantly promote the growth of cabbage seedlings, mainly reflected in that the number of leaves, stem diameter and fresh weight of cabbage increased significantly compared with the control, and the leaf area was extremely high compared with the control. significant increase. Without the use of chemical fertilizers, the statistical results of the fresh weight biomass of cabbage treated with microbial inoculum pf27 showed that the biomass of microbial inoculum pf27 on cabbage increased by 400.00%.

Example 6 Growth-promoting effect of microbial inoculant pf27 on cruciferous crops

1. Experimental method

According to the experimental method in Example 3, the seeds of Kuai Cai variety Siji Kuai Cai No. 1 (National Vegetable Engineering Technology Research and Development Center) were germinated until 2 true leaves grew, and the seedlings were transplanted into seedling trays (plug tray specifications). The diameter of the upper mouth is 9 cm, the diameter of the lower mouth is 6 cm, and the height is 8 cm), continue to cultivate under the above conditions, transplant 1 seedling in each culture pot, and repeat 9 times for each treatment, repeat 3 times without adding any Bacterial fluid served as a control. 22 days after transplanting, the number of leaves, fresh weight of each plant, and the area of 2 new leaves at the top of the fast food were counted, and the biomass increase was calculated. Increase in biomass (%)=(fresh weight of plants in treatment group – fresh weight of plants in control group)/fresh weight of plants in control group×100%.

2. Statistics on the effect of growth promotion

The results are shown in Figure 5. The microbial inoculant pf27 can significantly promote the growth of fast food seedlings, mainly reflected in the number of leaves, fresh weight and leaf area of fast food. Compared with the control group without any treatment, there are significant differences. Increase. Without the use of chemical fertilizers, the statistical results of the fresh weight biomass of four-season greens treated with microbial inoculant pf27 showed that the biomass of microbial inoculum pf27 increased by 137.27%.

Example 7. Effect of microbial inoculant pf27 on the growth-promoting effect of cruciferous crop Chinese cabbage

1. Experimental method

According to the experimental method in Example 3, the seeds of Chinese cabbage variety Beijing Xin No. 3 (National Vegetable Engineering Technology Research and Development Center) were germinated until 2 true leaves grew, and the seedlings were transplanted into seedling-raising plug trays (on the plug tray specifications). The diameter of the mouth is 9 cm, the diameter of the lower mouth is 6 cm, and the height is 8 cm), continue to cultivate under the above conditions, transplant 1 seedling in each culture pot, and repeat 9 times for each treatment, and repeat 3 times without adding any bacteria. liquid as a control. 22 days after transplanting, the number of leaves, fresh weight of each plant, and the area of two new leaves at the top of Chinese cabbage were counted, and the increase in biomass was calculated. Increase in biomass (%)=(fresh weight of plants in treatment group – fresh weight of plants in control group)/fresh weight of plants in control group×100%.

2. Statistics on the effect of growth promotion

The results are shown in Figure 6. The microbial inoculant pf27 can promote the growth of Chinese cabbage seedlings, which is mainly reflected in the significant increase in the number of leaves of Chinese cabbage compared with the control group without any treatment, and the fresh weight and leaf area are temporarily in a short period of time. No significant difference. Without the use of chemical fertilizers, the statistical results of the fresh weight biomass of Chinese cabbage treated with microbial inoculant pf27 showed that the biomass of Chinese cabbage increased by 9.72% with microbial inoculant pf27.

The comparison results of the growth-promoting effects of cruciferous cabbage, four-season green fast vegetables and Chinese cabbage are shown in Figure 7. The microbial agent pf27 has a significant growth-promoting effect on cruciferous cabbage and four-season green fast vegetables. The growth-promoting effect of Chinese cabbage Beijing Xin No. 3 is indeed not obvious, indicating that this pf27 inoculum is only suitable for some cruciferous crops.

Embodiment 8, the effect of microbial inoculum pf27 on the growth promotion of grass crop wheat

1. Experimental method

First, the wheat seeds Jinan 17 (JN17) were sterilized with 3% NaClO solution for 10 minutes, and washed with ddH ₂ O for 6 times to obtain the sterilized seeds. Then the sterilized seeds were evenly spread on a large flat plate with a layer of sterile filter layer. On the top, the sterilized ddH ₂ O filter paper was kept moist, and placed in a 37° C. incubator to promote germination overnight. After the embryos of the wheat seeds were germinated, according to the experimental method in Example 3, they were transplanted into seedling-raising plug trays (plug trays). The diameter of the upper mouth is 9 cm, the diameter of the lower mouth is 6 cm, and the height is 8 cm), and continue to be cultivated at room temperature. Several seeds are evenly transplanted in each culture pot, and each treatment is repeated 9 times, repeated 3 times, to No bacterial solution was added as a control. The growth trend of wheat was observed 27 days after transplanting, and the height trend changes of the lowest leaf and the highest leaf of the wheat seedlings were counted.

2. Statistics on the effect of growth promotion

The results are shown in Figure 8. The microbial agent pf27 can promote the early growth of wheat seedlings, which is mainly reflected in the fact that compared with the control group without any treatment, there is no significant difference in the minimum growth height of wheat seedling leaves, but the height of the highest leaves is not significantly different. The growth height was significantly higher than that of the control group.

Embodiment 9. The growth-promoting effect of microbial inoculum pf27 on the grass crop maize

1. Experimental method

First, the corn seed Mo17 (inbred corn line, gifted by researcher Zhang Xiaoming, Institute of Zoology, Chinese Academy of Sciences) was sterilized with 3% NaClO solution for 10 minutes, and washed with ddH ₂ O for 6 times to obtain the sterilized seeds, and then the sterilized seeds were evenly spread. On a large plate with a layer of sterile filter layer, keep the sterilized ddH ₂ O filter paper moist, and place it in a 37°C incubator overnight for germination. After the embryos and roots of the corn seeds germinate, follow the experimental method in Example 3 , transplant it into the seedling tray (the diameter of the upper opening of the plug tray is 9 cm, the diameter of the lower opening is 6 cm, and the height is 8 cm), and continue to be cultivated at room temperature. For corn seeds with no difference, 9 replicates for each treatment were repeated 3 times, and no bacterial solution was added as a control.

The stem diameter and plant height of each maize plant were counted 22 days after transplanting.

2. Statistics on the effect of growth promotion

The results are shown in Figure 9, the microbial inoculum pf27 can significantly promote the growth of maize seedlings, mainly reflected in the height and diameter (stem diameter) of the maize plant. Compared with the control group without any treatment, the microbial inoculant pf27 treated There is a very significant difference in stem thickness. The stem diameter of maize plants treated with microbial inoculant pf27 was 1.6 times that of the control group.

sequence listing

<110> Institute of Microbiology, Chinese Academy of Sciences

<120> A strain of Pseudomonas fluorescens pf27 and its application in plant growth promotion

<160>1

<210>1

<211>1508bp

<212> DNA

<213> Artificial sequences

<220>

<223>

<400>1

agagtttgat cctggctcag attgaacgct ggcggcaggc ctaacacatg caagtcgagc 60

ggtagagaga agcttgcttc tcttgagagc ggcggacggg tgagtaatgc ctaggaatct 120

gcctggtagt gggggataac gttcggaaac gaacgctaat accgcatacg tcctacggga 180

gaaagcaggg gaccttcggg ccttgcgcta tcagatgagc ctaggtcgga ttagctagtt 240

ggtgaggtaa tggctcacca aggcgacgat ccgtaactgg tctgagagga tgatcagtca 300

cactggaact gagacacggt ccagactcct acgggaggca gcagtgggga aaattggaca 360

atgggcgaaa gcctgatcca gccatgccgc gtgtgtgaag aaggtcttcg gattgtaaag 420

cactttaagt tgggaggaag ggcagttacc taatacgtga ttgttttgac gttaccgaca 480

gaataagcac cggctaactc tgtgccagca gccgcggtaa tacagagggt gcaagcgtta 540

atcggaatta ctgggcgtaa agcgcgcgta ggtggtttgt taagtaggat gtgaaatccc 600

cgggctcaac ctgggaactg cattcaaaac tgactgacta gagtatggta gagggtggtg 660

gaatttcctg tgtagcggtg aaatgcgtag atataggaag gaacaccagt ggcgaaggcg 720

accacctgga ctaatactga cactgaggtg cgaaagcgtg gggagcaaac aggattgata 780

ccctggtagt ccacgccgta aacgatgtca actagccgtt ggaagccttg agcttttagt 840

ggcgcagcta acgcattaag ttgaccgcct ggggagtacg gccgcaaggt taaaactcaa 900

atgaattgac gggggcccgc acaagcggtg gagcatgtgg tttaattcga agcaacgcga 960

agaaccttac caggccttga catccaatga actttctaga gatagattgg tgccttcggg 1020

aacattgaga caggtgctgc atggctgtcg tcagctcgtg tcgtgagatg ttgggttaag 1080

tcccgtaacg agcgcaaccc ttgtccttag ttaccagcac gtaatggtgg gcatctaagg 1140

agactgccgg tgacaaaccg gaggaaggtg gggatgacgt caagtcatca tggcccttac 1200

ggcctgggct acacacgtgc tacaatggtc ggtacagagg gttgccaagc cgcgaggtgg 1260

agctaatccc ataaaaccga tcgtagtccg gatcgcagtc tgcaactcga ctgcgtgaag 1320

tcggaatcgc tagtaatcgc gaatcagaat gtcgcggtga atacgttccc gggccttgta 1380

cacaccgccc gtcacaccat gggagtgggt tgcaccagaa gtagctagtc taaccttcgg 1440

gaggacggtt accacggtgt gattcatgac tggggtgaag tcgtaacaag gtaaccaagg 1500

gcgatccc 1508

Claims (9)

1. a fluorescent pseudomonads Pseudomonas fluorescens pf27, deposit number is CGMCC No. 14105。

2. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or the microbial inoculum containing it are promoting plant raw Application in length；

The Pseudomonas fluorescens Pseudomonas fluorescens is Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27。

3. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or the microbial inoculum containing it promote to plant in preparation Application in the product of strain growth；

The Pseudomonas fluorescens Pseudomonas fluorescens is Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27。

4. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or containing its microbial inoculum increase plant it is fresh Application in weight and/or fresh biomass；

The Pseudomonas fluorescens Pseudomonas fluorescens is Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27。

It is planted 5. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or the microbial inoculum containing it increase in preparation Application in the product of object fresh weight and/or fresh biomass；

The Pseudomonas fluorescens Pseudomonas fluorescens is Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27。

6. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or the microbial inoculum containing it are improving plant strain Answering in high and/or stem thickness and/or radical amount and/or blade quantity and/or blade area and/or maximum blade growing height With；

The Pseudomonas fluorescens Pseudomonas fluorescens is Pseudomonas fluorescens Pseudomonas Fluorescens pf27, deposit number are CGMCC No. 14105.

7. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or the microbial inoculum containing it are improved in preparation and are planted The production of object plant height and/or stem thickness and/or radical amount and/or blade quantity and/or blade area and/or maximum blade growing height Application in product；

The Pseudomonas fluorescens Pseudomonas fluorescens is Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27。

8. a kind of product, active constituent is Pseudomonas fluorescens Pseudomonas fluorescens described in claim 1 Pf27 or its bacteria suspension or the microbial inoculum containing it；

The product has following 1) -3) in any function:

1) promote plant strain growth；

2) increase plant fresh weight and/or fresh biomass；

3) plant plant height and/or stem thickness and/or radical amount and/or blade quantity and/or blade area and/or maximum blade are improved Growing height.

9. a kind of method for promoting plant growth, includes the following steps: with Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27 or its bacteria suspension handle plant seedlings.