CN107236689A - One fluorescent pseudomonads pf27 and its application in plant growth-promoting - Google Patents

Abstract

The invention discloses a Pseudomonas fluorescens pf27 and its application in plant growth promotion. The invention provides a strain of Pseudomonas fluorescens pf27, and prepares the microbial bacterial agent pf27. Experiments have proved that the plant height and root length of plants can be significantly improved after treatment with microbial agent pf27, and it has a certain growth-promoting effect on plants. Compared with the control group, the growth-promoting effect of the crops treated with pf27 exceeds 21.55%. It can reach up to 829.14%, and has a broad-spectrum and high-efficiency effect of promoting plant growth, especially to promote the growth and improve the quality of vegetable crops of the Solanaceae family. The invention solves the problems that other methods such as chemical fertilizers are ineffective or has residues, and helps to promote the sustainable development of agriculture, and has good application prospects.

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, 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 unlimited use of chemical pesticides and chemical fertilizers, they have polluted the human living environment and agricultural, forestry and animal husbandry products, endangered human and animal health and environmental resources such as water and soil, and restricted the sustainable development of agricultural production. It has become one of the serious social problems at present. For this reason, 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 focus. 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 between plants and microorganisms. In the plant-microbe system, microorganisms are connected to both the aboveground part of the plant (such as the leaf enclosure) and the underground part, thereby affecting the structure of the soil, the availability of nutrients in the soil, and producing some beneficial or harmful effects on the plant. metabolite.

Excessive application of several chemical fertilizers of a single nature will easily lead to nutritional imbalance of crops. Most of the chemical fertilizers contain various salts, among which chemical substances such as nitrogen, phosphorus, and potassium are easily consolidated by the soil and accumulate in the soil. The salinization of the soil causes the imbalance of soil nutrients, affects and hinders the transformation and absorption of the absorbed nutrients by crops, makes the growth characteristics of fruits and vegetables inferior, the taste and quality of crops deteriorate, and the quality declines. For example, vegetables taste unsavory and fruits taste bad It is not sweet, tastes poor, and is perishable, so it is not suitable for storage. A class of microorganisms in the soil, such as Pseudomonas fluorescens, Trichoderma, and Bacillus, can use their metabolic processes or metabolites to improve plant growth conditions, such as increasing nutrients, secreting hormones, stimulating plant root development, etc., and inducing plants to produce plant diseases. Such as late blight, defense response to root rot caused by Fusarium. The secondary metabolites produced by microorganisms contain substances that stimulate plant growth and development. 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 applying the effect of promoting plant growth obtained in greenhouse experiments to the field. Polymers produced by microorganisms have the ability to resist drought, reduce water stress, improve soil structure, supply plant organic nutrients and regulate ion activity. During their life activities, microorganisms can dissolve mineral elements in soil that are difficult for plants to use and transform them into It can be converted into a substance that promotes life, 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 the invalid state of soil minerals for plant growth and development. Microorganisms can promote the organic matter around the root system to form humic acid, improve the stress resistance of plants, degrade pollutants in the soil, reduce 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 alternatives. In recent years, microbial preparations have attracted much attention due to their characteristics of being environmentally friendly, promoting growth and increasing production, and preventing diseases. The use of beneficial microorganisms in the soil to develop microbial fertilizers is a research and development hotspot in recent years.

Contents of the invention

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

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

The Pseudomonas fluorescens pf27 of the present invention is classified as Pseudomonas fluorescens pf27, and the strain has been preserved in the General Microbiology Center of China Committee for Culture Collection of Microorganisms on May 8, 2017 (CGMCC for short, address : No. 3, No. 1 Yard, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, Zip Code 100101), the preservation number is CGMCC No.14105.

Another object of the present invention is to provide a new application of Pseudomonas fluorescens or its bacterial suspension or its culture liquid or its fermentation product or the bacterial agent containing it.

The invention provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture solution or its fermented product or the microbial agent containing the same in promoting plant growth.

The present invention also provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture liquid or its fermentation product or the microbial agent containing it in the preparation of products for promoting plant growth.

The present invention also provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture liquid or its fermentation product or the microbial agent containing the same in increasing the fresh weight and/or fresh weight biomass of plants.

The present invention also provides the application of Pseudomonas fluorescens or its bacterial suspension or its culture liquid or its fermentation product or the microbial agent containing it in the preparation of products for increasing plant fresh weight and/or fresh weight biomass.

The present invention also provides Pseudomonas fluorescens or its bacterium suspension or its culture liquid or its fermented product or the bacterium agent containing it to improve plant height and/or stem diameter and/or root number and/or blade Number and/or leaf area and/or maximum leaf growth height applied.

The present invention also provides Pseudomonas fluorescens or its bacterium suspension or its culture liquid or its fermented product or the bacterium agent containing it to improve plant height and/or stem diameter and/or root number and/or The number of leaves and/or the area of leaves and/or the height of the highest leaf growth applied in the product.

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

Yet another object of the 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 the bacterial agent containing it;

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

1) Promote plant growth;

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

3) Increase plant height and/or stem diameter 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 the growth of plants.

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

In the above method, the bacterial agent concentration for treating 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: the Pseudomonas fluorescens pf27 is cultivated in the KB culture medium to obtain the pf27 bacterial liquid, and the pf27 bacterial liquid is centrifuged to collect the precipitate; Dilute the precipitate with sterilized water to a concentration of 1×10 ⁹ -1×10 ¹⁰ CFU/mL to obtain the bacterial agent.

In the above-mentioned application or the above-mentioned product or the above-mentioned method, the plant is a Solanaceae plant, a Brassicaceae plant or a Poaceae plant. Specifically, the Solanaceae plants can be tomato and potato; the cruciferous plants can specifically be cabbage, cabbage and Chinese cabbage; and the Gramineae plants can specifically be wheat and corn.

The present invention screens Pseudomonas fluorescens pf27 through the redevelopment of the existing strains, and prepares the microbial bacterial agent pf27. Experiments have proved that the plant height and root length of plants can be significantly improved after treatment with microbial agent pf27, and it has a certain growth-promoting effect on plants. Compared with the control group, the growth-promoting effect of the crops treated with pf27 exceeds 21.55%. It can reach up to 829.14%, and has a broad-spectrum and high-efficiency effect of promoting plant growth, especially to promote the growth and improve the quality of vegetable crops of the Solanaceae family. The invention solves the problems that other methods such as chemical fertilizers are ineffective or has residues, and helps to promote the sustainable development of agriculture, and has good application prospects.

Description of drawings

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

Figure 2 shows the growth-promoting effect of the microbial agent pf27 on the Solanaceae crop tomato. A. The left picture shows the growth state of the Solanaceae crop tomato Zhongza No. 9 plant in the control group, and the right picture shows the growth state of the tomato plants under the pf27 bacterial agent treatment. The picture is taken 21 days after the plant transplantation; B. The tomato plant under the pf27 bacterial agent treatment Statistics of plant height and control group data; statistics of the total number of leaves of tomato plants under C.pf27 bacterial agent treatment and the total number of leaves of control group plants; statistics of fresh weight of tomato plants under D.pf27 bacterial agent treatment and fresh weight of control plants; E .pf27 bacterial agent treatment tomato plant diameter (stem diameter) and control group plant diameter (stem diameter) statistics; F.pf27 bacterial agent treatment the tomato plant top 2 new leaf area and control data statistics, all statistics plant 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 below.

Fig. 3 is the growth-promoting effect of the microbial agent pf27 on the Solanaceae crop potato. A. The state of growth of potato plants of Solanaceae crops in the control group on the left, and the growth state of potato plants under pf27 bacterial agent treatment in the right figure. The pictures were taken 4 weeks after transplanting; Control group plant data statistics; C.pf27 bacterial agent treatment under the total number of potato plant leaves and control data statistics; D.pf27 bacterial agent treatment under the potato plant rooting number and control group plant rooting number statistics; E.pf27 bacterial agent treatment The plant root length of potato and the control group plant root length data statistics; F.pf27 inoculum treatment potato and control group plant produce tuber situation comparison; G.pf27 process under potato and control group plant produce tuber total weight data statistics, n= 6, 3 repetitions.

Figure 4 shows the growth-promoting effect of the microbial agent pf27 on the cruciferous crop Brassica oleracea. A. The control group Brassicaceae cabbage plants in the left picture, and the growth state of the cabbage plants treated with pf27 inoculum in the right picture. The pictures were taken 33 days after plant transplantation; Statistics of the plant area of the control group, 2 new leaves at the top of each plant; statistics of the total number of leaves of cabbage under the treatment of C.pf27 and the total number of leaves of the control group; data of the fresh weight of cabbage plants under the treatment of D.pf27 and the fresh weight of the control group Statistics; the plant diameter (stem diameter) of cabbage treated with E.pf27 bacterial agent was compared with the plant diameter (stem diameter) of the control group, n=9, repeated 3 times.

Figure 5 shows the growth-promoting effect of the microbial agent pf27 on the cruciferous crop Four Seasons Green Vegetables. A. The left picture shows the growth state of the Sijiqing Express vegetables in the control group, and the right picture shows the growth status of the Four Seasons Green Express vegetables treated with the pf27 bacterial agent. The pictures were taken 22 days after the plant transplantation; B. The Sijiqing Express vegetables were treated with the pf27 bacterial agent Statistics on the total number of leaves of the plants in the control group; the fresh weight of the plants of Sijiqing Kuaicai under the treatment of C.pf27 and the fresh weight of the plants of the control group; For plant area, 2 top new leaves were counted for each plant, n=9, repeated 3 times.

Figure 6 shows the effect of the microbial agent pf27 on the growth-promoting effect of Chinese cabbage, a cruciferous crop. A. The left picture shows the growth status of Chinese cabbage Beijing Xin No. 3 plants in the control group, and the right picture shows the growth status of Chinese cabbage plants treated with pf27 bacterial agent. The pictures were taken 22 days after plant transplantation; B. Chinese cabbage treated with pf27 bacterial agent Statistics of the total number of leaves of the plants in the control group; the fresh weight of Chinese cabbage plants under the treatment of C.pf27 bacterial agent and the fresh weight of the plants of the control group; Count 2 top new leaves per plant, n=8, 3 repetitions.

Figure 7 shows the effect of the microbial agent pf27 on the growth-promoting effect of cruciferous crops. A. The total amount of cruciferous cabbage plants treated with pf27 bacterial agent on the right, and the total amount of cabbage plants in the control group on the left, n=9; Quantity, the total amount of cabbage plants in the control on the left, n=9; C. The total amount of plants of Brassicaceae Chinese cabbage Beijing Xin No. 3 treated with pf27 bacterial agent in the right figure, the total amount of plants in the control cabbage in the left figure, n=8; D. Cabbage , Statistics on biomass changes of Sijiqing Kuaicai and Chinese cabbage Beijing Xin No. 3.

Figure 8 shows the effect of the microbial agent pf27 on the growth-promoting effect of the grass crop wheat. A. Comparison of the growth status of Gramineae wheat JN17 plants in the control group on the left, and the growth status of wheat plants under pf27 bacterial agent treatment in the right graph, n=9; B. The minimum leaf height of wheat JN17 plants under the pf27 bacterial agent treatment and the control group Statistics of the difference between (Low) and highest height (High), n=9, the pictures were taken 27 days after sowing.

Figure 9 shows the effect of the microbial agent pf27 on the growth-promoting effect of the grass crop corn. A. The growth trend chart of gramineous corn Mo17 plants in the left picture of the control group, and the right picture of the gramineous corn Mo17 plants treated with pf27 inoculum. The pictures were taken 22 days after transplanting, n=9, and repeated 3 times; B.pf27 bacteria The comparison of stem diameter of Gramineae corn Mo17 under C.pf27 inoculum treatment and control group; the comparison of Gramineae corn Mo17 under C.pf27 inoculum treatment and the control group; Gramineae corn Mo17 and Comparison of plant height of corn plants in control group; comparison of stem diameter of corn plants in Gramineae plant Mo17 and control group treated with E.pf27 inoculum.

Preservation instructions

Species name: Pseudomonas fluorescens

Latin name: Pseudomonas fluorescens

Strain number: pf27

Preservation institution: General Microbiology Center of China Committee for the Collection of Microorganisms

Depository institution abbreviation: CGMCC

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

Deposit date: May 8, 2017

Registration number of the collection center: CGMCC No.14105

detailed description

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

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

The quantitative tests in the following examples were all set up to repeat the experiments three times, and the results were averaged.

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

MEA medium: Malt extract 30g, Mycological peptone 5g, agar powder 15g, pH5.4;

Beef extract peptone medium: peptone 10g, beef extract 3g, sodium chloride 5g, agar powder 12g, water 1000ml, pH7.2-7.4;

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 to 1L, pH 7.0; solid medium plus agar powder 12g.

The isolation and identification of embodiment 1, pf27 bacterial strain

1. Isolation of pf27 strain

pf27 was isolated from the rhizosphere soil of the wild rice field in Pu'er City, Yunnan Province ( ^22. 33'56", ^100. 35'12", 737 meters above sea level). The specific separation method is as follows: pick the rhizosphere soil collected from the verrucous wild rice area, pick the root system, scrape the rhizosphere soil, weigh 5g, put it into the prepared sterilized triangular flask under aseptic conditions, and use sterilized Water gradient dilution to 10 ^-6 times, set 3 replicates. Take 200 μl of the soil samples that were diluted in gradient and spread them on MEA medium, beef extract peptone medium, LB medium and KB medium plates respectively, culture them in 28°C and 37°C incubators, and observe the growth status of the colonies every day. The results showed that when the dilution was 10 ^-5 and 10 ^-6 times, there were basically no colonies growing on the plate, but when the dilution was 10 ^-4 times, a single colony could grow on the plate, and picked out to grow on the KB medium A single colony was named pf27 strain, and then expanded and cultured 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 being cultured on KB medium for 24h to 48h. The colony is round, with smooth surface and raised edges. It is sticky and easy to stir up.

2. Molecular identification of pf27 strain

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

Eubac27F: 5'-AGAGTTTGATCCTGGCTCAG-3';

Eubac1492R: 5'-GGTTACCTTGTTACGACTT-3'.

The PCR product was cloned by TA and connected to pEASY-T3 (purchased from Beijing Quanshijin Biological Co., Ltd.), and sequenced at Yingwei Jieji Company with universal primers.

Sequencing results show that: the nucleotide sequence of the PCR product is shown in sequence 1. After blasting the sequence obtained from the sequencing with the NCBI database, the phylogenetic analysis was performed on pf27 and other Pseudomonas fluorescent strains representing 22 different Pseudomonas species by MEGA5.1 software. The phylogenetic tree is shown in Figure 1 Show.

Based on the above identification results, the name of the pf27 strain was determined to be Pseudomonas fluorescens, and its classification was named Pseudomonas fluorescens. (CGMCC for short, address: No. 3, Courtyard No. 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, Zip code 100101), and the preservation number is CGMCC No.14105.

Embodiment 2, the preparation of microbial bacterial agent pf27

The Pseudomonas fluorescens pf27 obtained in Example 1 was shaken and cultured in KB medium, shaken and cultured at 28°C and 200rpm for 12-16h, then centrifuged at 4000rpm for 20min, discarded the supernatant, and collected the bacterial cell precipitate , and then dilute the bacterial precipitate with sterilized water to make microbial agent pf27 (bacteria agent pf27). The total concentration of pf27 viable bacteria in the finished product of microbial agent pf27 is 1×10 ⁹ -1×10 ¹⁰ CFU/mL.

Embodiment 3, the growth-promoting effect of microbial bacterial agent pf27 on tomato seedlings of Solanaceae crops

1. Experimental method

Zhongza No. 9 tomato seeds (produced by Zhongshu Seed Industry Technology (Beijing) Co., Ltd.) were sterilized with 3% NaClO solution for 10 minutes, and washed 6 times with ddH ₂ O to obtain sterilized seeds. Then spread the sterilized seeds evenly on the sterilized vermiculite peat soil matrix (mix the vermiculite and peat soil according to the ratio of 1:1, autoclave at 121°C, 20min), and germinate at 26°C, 12h:12h light: Cultivate the seeds to germinate under dark conditions, and when the seeds germinate and grow to two true leaves, they are transplanted into the evenly added bacterial agent pf27 (using a concentration of 50ml of bacterial solution with an OD value of 1 for each kg of vermiculite peat soil matrix mixture, The final concentration of the bacterial solution was 1×10 ⁵ CFU/mL) and the nutrient hole of the control, and the tomato seedlings were transplanted into the seedling trays (the diameter of the upper opening of the tray is 9 cm, the diameter of the lower opening is 6 cm, and the height is 8 cm) , placed in a greenhouse to grow (conditions: light time 12h, temperature 26°C, relative humidity 50%). Continue to place and cultivate under the above-mentioned conditions, transplant 1 seedling in each culture pot, and each process has 27 repetitions. No addition of any bacterial agent was used as the control (Control). After 33 days of transplanting, count the height of each plant, the number of leaves, the fresh weight of the tomato plant, the thickness of the stem of the tomato plant, the leaf area of 2 new leaves at the top of the tomato, and calculate the increase in biomass. Biomass increase (%)=(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 growth-promoting effect

The result is shown in Figure 2. Microbial agent pf27 can produce obvious growth-promoting effect on tomato seedlings. Compared with the control group, the average plant height of tomato plants after the treatment of microbial agent pf27 increased by 18%, the number of leaves increased by 23%, and the plant diameter (stem diameter) It was 2.5 times that of the control group, while the pf27 treatment increased the leaf area by as much as 5 times, and the biomass of tomato plants increased by 771.16%.

Embodiment 4, the growth-promoting effect of microbial bacterial agent pf27 on potato seedlings of Solanaceae crops

1. Experimental method

The potatoes purchased from Beijing Shouhang Supermarket were picked and placed in a humid and dark environment. After a week, healthy potato shoots with consistent sprouts were picked and cut off with 70% alcohol sterilized blades. Then the young shoots are transplanted into plastic flowerpots (specification upper opening diameter: 14 cm, lower opening diameter 9.5 cm, height 12.5 cm) evenly added bacterial agent pf27 (50ml/Kg, final concentration of bacterial solution at 10 ⁵ CFU/mL) ) and sterilized vermiculite matrix (mixed according to the ratio of 1:1, autoclaved at 121 ℃, 20min), the surface is covered with a layer of plastic wrap to keep moisture, after cotyledon grows, it is removed, and placed in the greenhouse for growth (Conditions: light time 12h, temperature 26°C, relative humidity 50%). No addition of any bacterial agent was used as the control (Control), and 16 seedlings were treated for each treatment, with 3 repetitions. After 28 days of transplanting, count the plant height, leaf number, root length, root number and potato tuber situation of potatoes, and calculate the biomass increase. Biomass increase (%)=(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 growth-promoting effect

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, compared with the control, the number of leaves and roots increased by 114% and 50%, respectively. In the absence of chemical fertilizers, the yield of potatoes treated with microbial agent pf27 increased significantly, and the statistical results showed that microbial agent pf27 increased the biomass of potatoes by 1115.15%.

Example 5, the growth-promoting effect of microbial agent pf27 on cruciferous crop cabbage

1. Experimental method

According to the experimental method in embodiment 3, the seeds of cabbage variety Jingfeng No. 1 (Vegetable and Flower Research Institute, Chinese Academy of Agricultural Sciences) are germinated until 2 true leaves are grown and the seedlings are transplanted in the seedling tray (on the tray specification). Mouth diameter 9 centimeters, lower mouth diameter 6 centimeters, height 8 centimeters), continue to place and cultivate under the above-mentioned conditions, transplant 1 seedling in each culture pot, each process 9 repetitions, repeat 3 times, with not adding any bacteria agent as a control. After 33 days of transplanting, the number of leaves of each plant, the fresh weight of the plant, the stem diameter of the cabbage plant, and the leaf area of the two new leaves at the top of the cabbage were counted, and the biomass increase was calculated. Biomass increase (%)=(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 growth-promoting effect

The results are shown in Figure 4. The microbial agent pf27 can significantly promote the growth of cabbage seedlings, mainly reflected in that the number of leaves, stem diameter and fresh weight of cabbage are significantly increased compared with the control, and the leaf area is significantly higher than that of the control. Significant increase. In the case of no chemical fertilizers, the statistical results of fresh weight biomass of cabbage treated with microbial agent pf27 showed that microbial agent pf27 increased the biomass of cabbage by 400.00%.

The growth-promoting effect of embodiment 6 microbial bacterial agent pf27 to cruciferous crop fast dish

1. Experimental method

According to the experimental method in embodiment 3, the seeds of fast vegetable variety Sijikuaicai No. 1 (National Vegetable Engineering Technology Research and Development Center) are germinated until 2 true leaves are grown and the seedlings are transplanted in the seedling tray (tray specification Upper mouth diameter 9 centimeters, lower mouth diameter 6 centimeters, height 8 centimeters), continue to place and cultivate under the above-mentioned conditions, transplant 1 seedling in each culture pot, each process 9 repetitions, repeat 3 times, to not add any Bacteria as a control. After 22 days of transplanting, count the number of leaves of each plant, the fresh weight of the plant, and the leaf area of 2 new leaves at the top of the fast vegetable, and calculate the increase in biomass. Biomass increase (%)=(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 growth-promoting effect

The results are shown in Figure 5. The microbial agent pf27 can significantly promote the growth of fast vegetable seedlings, mainly reflected in the number of leaves, fresh weight and leaf area of fast vegetable. Compared with the control group without any treatment, there is a significant difference. Increase. In the case of no chemical fertilizers, the statistical results of fresh weight biomass of Sijiqing fast vegetables treated with microbial agent pf27 showed that microbial agent pf27 increased the biomass of fast vegetables by 137.27%.

Example 7, the influence of microbial agent pf27 on the growth-promoting effect of cruciferous crop Chinese cabbage

1. Experimental method

According to the experimental method in embodiment 3, the seed of Chinese cabbage variety Beijing No. 3 (National Vegetable Engineering Technology Research and Development Center) is germinated until 2 true leaves are grown and the seedlings are transplanted in the seedling tray (on the tray specification) Mouth diameter 9 centimeters, lower mouth diameter 6 centimeters, height 8 centimeters), continue to place and cultivate under the above-mentioned conditions, transplant 1 seedling in each culture pot, each process 9 repetitions, repeat 3 times, with not adding any bacteria liquid as a control. After 22 days of transplanting, the number of leaves of each plant, the fresh weight of the plant, and the leaf area of the two new leaves at the top of Chinese cabbage were counted, and the increase in biomass was calculated. Biomass increase (%)=(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 growth-promoting effect

The results are shown in Figure 6. The microbial agent pf27 can promote the growth of Chinese cabbage seedlings, 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 temporarily decreased in a short period of time. No significant difference. In the absence of chemical fertilizers, the statistical results of fresh weight biomass of Chinese cabbage treated with microbial agent pf27 showed that the biomass of Chinese cabbage increased by microbial agent pf27 reached 9.72%.

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

Embodiment 8, the effect of microbial bacterial agent pf27 on the growth promotion of gramineous crop wheat

1. Experimental method

Firstly, the wheat seeds Jinan 17 (JN17) were sterilized with 3% NaClO solution for 10 minutes, washed with ddH ₂ O for 6 times to obtain sterilized seeds, and then evenly spread the sterilized seeds on a large plate with a sterile filter layer Above, keep the sterilized ddH ₂ O filter paper moist and place it in a 37°C incubator to accelerate germination overnight. After the embryos of wheat seeds germinate, they are transplanted into seedling trays according to the experimental method in Example 3 (plug trays) The diameter of the upper mouth of the specifications is 9 centimeters, the diameter of the lower mouth is 6 centimeters, and the height is 8 centimeters), continue to be placed under room temperature conditions, and several strains of seeds are evenly transplanted in each culture pot, and each treatment is repeated 9 times, and repeated 3 times. No bacterial solution was added as a control. After 27 days of transplanting, the wheat growth trend was observed, and the height trend changes of the lowest leaves and the highest leaves of the wheat seedlings were counted.

2. Statistics on growth-promoting effect

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 lowest growth height of wheat seedling leaves, but the height of the highest leaves The growth height was significantly higher than that of the control group.

Embodiment 9, the growth-promoting effect of microbial bacterial agent pf27 on grass crop corn

1. Experimental method

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

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

2. Statistics on growth-promoting effect

The results are shown in Figure 9, microbial agent pf27 can significantly promote the growth of corn seedlings, mainly reflected in the height and diameter (stem thickness) of corn plants, compared with the control group without any treatment, the microbial agent pf27 treated Stem thickness has a very significant difference. The stem diameter of the corn plants treated with microbial agent pf27 was 1.6 times that of the control group.

sequence listing

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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 (10)

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

2. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or its nutrient solution or its tunning contain There is application of its microbial inoculum in plant strain growth is promoted.

3. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or its nutrient solution or its tunning contain There is application of its microbial inoculum in the product for promoting plant strain growth is prepared.

4. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or its nutrient solution or its tunning contain There is application of its microbial inoculum in increase plant fresh weight and/or fresh biomass.

5. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or its nutrient solution or its tunning contain There is application of its microbial inoculum in the product of increase plant fresh weight and/or fresh biomass is prepared.

6. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or its nutrient solution or its tunning contain There is its microbial inoculum improving thick plant plant height and/or stem and/or radical amount and/or blade quantity and/or blade area and/or most Application in high leaf growth height.

7. Pseudomonas fluorescens Pseudomonas fluorescens or its bacteria suspension or its nutrient solution or its tunning contain Have its microbial inoculum prepare improve thick plant plant height and/or stem and/or radical amount and/or blade quantity and/or blade area and/ Or the application in the product of maximum blade growing height.

8. according to any described method in claim 2-7, it is characterised in that：The Pseudomonas fluorescens Pseudomonas Fluorescens is the Pseudomonas fluorescens Pseudomonas fluorescens pf27 described in claim 1.

9. a kind of product, its active component is the Pseudomonas fluorescens Pseudomonasfluorescens described in claim 1 Pf27 or its bacteria suspension or its nutrient solution or its tunning or the microbial inoculum containing it；

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

1) plant strain growth is promoted；

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

3) improve that plant plant height and/or stem be thick and/or radical amount and/or blade quantity and/or blade area and/or maximum blade Growing height.

10. a kind of method of promotion plant growth, comprises the following steps：With the Pseudomonas fluorescens described in claim 1 Pseudomonas fluorescens pf27 or its bacteria suspension processing plant seedlings.