CN105754900B

CN105754900B - Novel Erwinia strain for promoting crop drought resistance and application thereof

Info

Publication number: CN105754900B
Application number: CN201610228010.XA
Authority: CN
Inventors: 张磊; 陈超琼; 辛凯芸; 沈锡辉
Original assignee: Northwest A&F University
Current assignee: Northwest A&F University
Priority date: 2016-04-13
Filing date: 2016-04-13
Publication date: 2020-04-17
Anticipated expiration: 2036-04-13
Also published as: CN105754900A

Abstract

The invention discloses a new species of Erwinia alhagi for promoting crop drought resistance and application thereof, the species is obtained by separating leaf tissues of Alhagi sparsifolia collected in Xinjiang desert area in China, the code is LTYR-11Z, the species is preserved in China center for type culture collection in 2016, 1 month and 18 days, the preservation number is CCTCC M2016052, and the species is named as Erwinia alhagi. The Erwinia ahagi LTYR-11Z new species of Erwinia has plant growth promotion effects of generating plant growth hormone indoleacetic acid, secreting siderophores, dissolving insoluble inorganic phosphate and the like, and has a certain inhibition effect on plant pathogenic fungi wheat root rot fungi. The live bacterial preparation prepared from the novel Erwinia can be used as an inoculant to be applied to agricultural production in a drought habitat, so that the growth of crops is promoted, and the drought resistance of the crops is improved.

Description

Novel Erwinia strain for promoting crop drought resistance and application thereof

Technical Field

The invention belongs to the technical field of microorganisms, and relates to a new species of Erwinia capable of promoting crop drought resistance and application thereof.

Background

It is well known that water resource shortage and soil salinization are major problems facing agricultural production worldwide. With global climate deterioration, extreme weather such as high temperature, drought, flood, low temperature freeze injury frequently appears all over the world, and also poses great threat to global grain production. According to statistics, the land suitable for cultivation is less than 10% in the world, and most of the land is in adverse environments such as drought, salinization, swamp, cold soil and the like. Adverse conditions such as drought, saline-alkali, high temperature, low temperature and the like are abiotic stress factors for inhibiting the growth and development of plants, and cause a series of morphological, physiological and biochemical changes, and even death of the whole plant in severe cases. Moreover, the growing population has more and more pressure on the demand of food, and economic crops adapting to various adversity stresses are urgently needed to be cultivated. Therefore, how to improve crop stress resistance is always a concern of agricultural ecology in all countries of the world.

In addition to the genetic nature of the plant itself, recent studies have shown that the presence of endogenous microorganisms in some plant tissues plays an important role in the host plant's resistance to adverse environmental stresses. The endophyte can regulate the active oxygen toxicity and osmotic balance of plant tissues under drought stress from the aspects of osmotic regulating substances, an antioxidant system, drought-related genes, physiological indexes, hormone balance and the like of the plants, thereby relieving the damage of the drought stress to the plants and enabling the plants to grow in a water-deficient environment. Therefore, the plant endophyte resource can be developed and utilized as an advantageous tool for relieving drought stress of the crops in the drought region. Some research results also show that the plant endophyte has one-to-one correspondence to the host plant in the stress resistance capacity. For example, endophytes isolated from coastal, drought, and high temperature habitats confer resistance to salt, drought, and high temperature, respectively, to host plants. Therefore, endophyte resources are searched from plant tissues which live in drought stress environment for a long time in the nature to develop a novel microbial agent capable of assisting crops in resisting drought stress, the microbial agent is applied to agricultural production in drought and water-deficient areas, and the novel approach is a new approach for improving stress resistance of crops in the future drought areas.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a new Erwinia strain with the function of promoting crop drought resistance and application thereof.

The technical scheme is as follows:

a new species of Erwinia species for promoting crop drought resistance is obtained by separating leaf tissues of Alhagi sparsifolia collected in Xinjiang desert area in China, the code is LTYR-11Z, the strain is preserved in China center for type culture collection (GmbH university in Wuhan, China) at 18 months 1, the preservation address is CCTCC M2016052, and the Erwinia alhagi (Erwinia alhagi) is classified and named.

Preferably, the new species form and culture characteristics of erwinia are specifically: after culturing for 1d at 30 ℃ on an LB culture medium, the bacterial colony is yellow and semi-wet and convex; the strain cell is rod-shaped and has flagellum structure as observed by transmission electron microscope.

Preferably, the 16S rRNA gene sequence of the novel Erwinia species is shown in SEQ ID NO. 1.

Preferably, the sequence of the recA gene fragment of the new Erwinia species is shown in SEQ ID NO. 2.

Preferably, the sequence of the gpd gene fragment of the novel Erwinia species is shown in SEQ ID NO. 3.

Preferably, the new species of erwinia has the effect of dissolving inorganic phosphorus which is poorly soluble.

Preferably, the new species of erwinia are capable of producing Indole Acetic Acid (IAA).

Preferably, the new species of erwinia are capable of producing a siderophore.

The new Erwinia species is applied to the process of improving the drought resistance of crops.

Preferably, the crops are wheat and Chinese cabbage.

The application of the novel Erwinia species in the process of promoting the growth of crops is disclosed.

The invention has the beneficial effects that:

the novel Erwinia species can generate a plant growth hormone indoleacetic acid and promote the growth and development of plant tissues. The strain can also secrete siderophore, dissolve insoluble inorganic phosphate, promote symbiotic host plants to absorb and utilize inorganic nutrient elements such as iron and phosphorus, and promote their growth.

The novel Erwinia strain has a certain antagonistic action on plant pathogenic fungi wheat root rot fungi, and is beneficial to improving the capability of crops for resisting pathogenic fungi diseases.

The erwinia new species is obtained by separating leaf tissues of a drought-tolerant plant alhagi growing in extremely arid desert areas in Xinjiang, can be colonized in crops such as wheat, Chinese cabbage and the like, and improves the resistance of host plants to drought stress.

Drawings

FIG. 1 is a photograph of Erwinia ahagi LTYR-11Z colonies on LB medium and R2A medium;

FIG. 2 is a photograph of a colony of fructan-producing Erwinia ahagi LTYR-11Z on LB + 5% sucrose medium;

FIG. 3 is a phylogenetic tree constructed from Erwinia ahagi LTYR-11Z and related model strains according to the 16S rRNA gene sequence;

FIG. 4 is a photograph of Erwinia ahagi LTYR-11Z on inorganic phosphorus solid medium for solubilizing phosphorus;

FIG. 5 is a photograph of Erwinia ahagi LTYR-11Z producing siderophores on CAS medium;

FIG. 6 is a photograph showing the plate confrontation experiment of Erwinia ahagi LTYR-11Z and wheat root rot fungi;

FIG. 7 is a comparison of growth status of non-inoculated wheat seedlings (second pot) and Erwinia ahagi LTYR-11Z-inoculated wheat seedlings (third pot) under drought stress conditions and two sets of no-drought controls (first and fourth pots);

FIG. 8 is a comparison of root length and stem length of non-inoculated wheat seedlings under drought stress conditions with Erwinia ahagi LTYR-11Z-inoculated wheat seedlings;

FIG. 9 is a comparison of fresh weights of non-inoculated wheat seedlings under drought stress conditions with Erwinia ahagi LTYR-11Z-inoculated wheat seedlings;

FIG. 10 is a comparison of growth status of non-inoculated plantlets of Brassica rapa (first pot) and plantlets of Erwinia ahagiLTYR-11Z inoculated plantlets (second pot) under drought stress conditions;

FIG. 11 is a comparison of fresh weights of non-inoculated plantlets of Brassica rapa vs. plantlets of Erwinia ahagi LTYR-11Z under drought stress conditions.

Detailed Description

The method of the present invention is described in further detail below with reference to the figures and specific examples.

The Erwinia new species related to the invention is obtained by separating the leaf tissue of Alhagi sparsifolia collected in Xinjiang desert area in China, the code is LTYR-11Z, the strain is preserved in China center for type culture collection in 2016, 1 month and 18 days, the preservation number is CCTCC M2016052, and the Erwinia alhagi (Erwinia alhagi) is classified and named.

1. Isolation of the novel species of Erwinia

Collecting alhagi sparsifolia plant samples from Xinjiang desert areas, disinfecting the surfaces of leaf plant tissues, cutting the alhagi sparsifolia plant samples into fragments by using disinfected scissors, placing the fragments on an R2A solid culture medium containing 50 mu g/mL cycloheximide, culturing for 1 week at 28 ℃, selecting off-white lawn growing around the leaves, streaking and purifying to obtain a strain LTYR-11Z, carrying out classification and identification on phenotype and genetic characteristics to determine the strain to be a new species of Erwinia, namely the Erwinia sparsifolia (Erwinia ahagi)

2. Morphological characteristics of the novel Erwinia species of the present invention

As shown in FIG. 1, Erwinia camelina (Erwinia alhagi LTYR-11Z) was streaked on LB plate and cultured for 24 hours to form a circular, opaque, semi-moist, convex yellow colony (left) with a diameter of 2-5 mm; the strain is streaked on an R2A plate and cultured for 24h to form a round, opaque, semi-moist and raised off-white colony with the diameter of 2-4mm (right). The microscopic observation result of a transmission electron microscope shows that the cells of the strain are rod-shaped, have flagella and can move.

3. Physiological and biochemical characteristics of the novel Erwinia species

The Erwinia ahagiLTYR-11Z new species can grow on various solid culture media such as TSA, R2A, Marine Agar 2216, Nutrient Agar, MacConkey Agar, LB and the like, can tolerate 0-7% NaCl within the growth temperature range of 7-48 ℃ and the growth pH range of 5.0-9.0; belongs to facultative anaerobes and grows well under aerobic and anaerobic conditions; can produce catalase and cytochrome oxidase, can grow by using various saccharides such as glucose, arabinose, mannose, maltose, etc. as a unique carbon source, and can hydrolyze casein. As shown in FIG. 2, the strain was streaked on LB plates containing 5% sucrose to form a large white, viscous, dome-shaped colony, indicating that the strain is capable of degrading sucrose to convert to fructan.

4.16S rRNA Gene, recA Gene and gpd Gene sequence analysis

Extracting genome DNA of strain LTYR-11Z, amplifying 16S rRNA gene fragment by using 16S rRNA gene universal primers 27f (5'-AGAGTTTGATCCTGGCTCAG-3') and 1492r (5'-CGGTTACCTTGTTACGACTT-3'), amplifying recA gene fragment by using recA gene universal primers RECA1 (5'-GGTAAAGGGTCTATCATGCG-3') and RECA2c (5'-CCTTCACCATACATAATTTGGA-3'), amplifying gpd gene fragment by using gpd gene universal primers GAP11 (5'-ACGGCACTGTAGAAGTC-3') and GAP12c (5'-CCAGTCTTTGTGAGACG-3'), respectively connecting into pMD19-T vector, transferring into escherichia coli competent cell, selecting positive clone, sequencing, and respectively obtaining 16S rRNA gene, recA gene and gpd gene sequences.

The 16S rRNA gene sequence of Erwinia ahagi LTYR-11Z of the new Erwinia is shown as SEQ ID NO. 1. The 16S rRNA gene sequence is submitted to GenBank database for multiple sequence comparison, and is subjected to sequence similarity analysis with a model strain with an effective table, and the sequence similarity analysis is found to be similar to the model strain Erwinia uzeensis YPPS 951 of Erwinia^T，Erwinia piriflorinigrans CFBP 5888^TAnd Erwinia pyrifoliae DSM 12163^TThe sequence similarity of (A) was the highest, 97.5%, 97.4% and 97.4%, respectively. According to the theory of the famous bacteria classmate Stackebrandt et al, bacteria with 16SrRNA gene sequence similarity less than 98.7% are due to different species. The sequence similarity of the strain LTYR-11Z and the 16S rRNA of the existing model strain of the Erwinia is below 97.5 percent, which shows that the strain has larger difference with the known species of the Erwinia and is a new species of the Erwinia. The 16S rRNA gene sequence of the strain LTYR-11Z and related Erwinia strains is usedThe ClustalX 1.81 software is compared,then, a phylogenetic tree is constructed by using an adjacency method, and the result is shown in fig. 3. It can be seen from the phylogenetic tree (FIG. 3) that the strain LTYR-11Z is located in a separate branch within the taxonomic cluster of all the model strains of Erwinia, indicating that this strain has a large difference in taxonomic status from the model strains of other species of Erwinia.

The sequence of a partial recA gene fragment of Erwinia ahagi LTYR-11Z of the new Erwinia is shown as SEQ ID NO. 2. The model strain Erwinia uzenensis YPPS 951 with the recA gene sequence closest to the genetic relationship^T，Erwinia piriflorinigrans CFBP 5888^TAnd Erwinia pyrifoliae DSM 12163^TThe similarity of (a) was only 84.9%, 85.1% and 85.1%.

The sequence of a partial gpd gene fragment of Erwinia ahagi LTYR-11Z of the new Erwinia is shown as SEQ ID NO. 3. The gpd gene sequence and the model strain Erwinia uzenensis YPPS 951^TAnd Erwiniapiririferinigorirans CFBP 5888^TThe similarity of (a) was only 81.1% and 82.2%.

In summary, the results of sequence similarity comparison and phylogenetic analysis of the 16S rRNA gene sequence and two conserved genes recA and gpd show that the strain LTYR-11Z has larger genetic difference with related model strains of Erwinia, and is a new species of Erwinia, and is named as Erwinia alhagi (Erwinia alhagi).

5. The determination of the capability of producing indoleacetic acid (IAA) of the novel Erwinia

Erwinia ahagi LTYR-11Z, a new species of Erwinia ahagi, was inoculated into SMS broth [ sucrose 10g, (NH) containing 0.5mg/ml L-tryptophan₄)₂SO₄1g、K₂HPO₄2g、MgSO₄0.5g、Yeast extract 0.5g、CaCO₃0.5g, NaCl 30g, 1000mL of distilled water, pH 7.2]Shaking at 30 deg.C and 180rpm for 3 d. Spectrophotometric determination of OD of bacterial suspension₆₀₀Then the bacterial suspension is centrifuged at 10000rpm for 10min, and the supernatant is added with an equal volume of Salkowski colorimetric solution (50mL of 35% HClO)₄+1mL 0.5M FeCl₃) Standing in dark for 30min, and determining OD₅₃₀The value is obtained. Calculating the bacterial concentration OD₆₀₀At a value of 1, the IAA content per volume of fermentation broth (the IAA content is calculated from a standard curve of a gradient dilution of the IAA). Through determination, the IAA yield of the new Erwinia species can reach 17.73 mu g/(mL. OD)₆₀₀)。

6. Experiment for dissolving inorganic phosphorus by using novel Erwinia

Erwinia ahagi LTYR-11Z is inoculated in a refractory inorganic phosphorus solid culture medium [10g of glucose and 5.0g of Ca₃(PO4)₂、0.5g(NH₄)₂SO₄、0.2g NaCl、0.2g KCl、0.03g MgSO₄·7H2O、0.03gMnSO₄、0.003g FeSO₄0.5g of yeast extract, 20g of agar and 1000mL of distilled water, and the pH value is 6.8-7.0]Culturing at 30 deg.C, and observing whether degradation ring appears. As shown in FIG. 4, after 3 days of culture on inorganic phosphorus solid medium, a transparent circle appeared around the lawn of the new species of Erwinia, indicating that the species can dissolve the insoluble inorganic phosphorus.

7. Detection of siderophore production ability of novel Erwinia species

60.5mg of CAS (chromium azure) was dissolved in 50mL of ddH₂In O, with 10mL of an iron solution (1mmol/L FeCl)₃And 10mmol/L HCl) solution to obtain solution A; 72.9mg of HDTMA (hexadecyltrimethylammonium bromide) were dissolved in 40mL of ddH₂O, obtaining a solution B; and slowly adding the solution A into the solution B, and fully and uniformly mixing to obtain the CAS dyeing liquid. Preparation of CAS detection plate: each 100mL of the solution containing 20% of sucrose and 3mL of 10% acid-hydrolyzed casein, 1mmol/L of CaCl₂100μL，1mmol/LMgSO₄2mL of agar, 1.8g, and slowly adding 10 XMM 9 salt solution (Na) at about 60 deg.C₂HPO₄·12H₂O 2.427g，NaH₂PO₄·2H₂O 0.5905g，KH₂PO₄0.075g，NH₄Cl 0.250g，NaCl0.125g，100mL ddH₂O, adjusting pH to 6.8) and CAS stain 5mL each, shaking well (but without bubbles) to obtain blue detection medium. The Erwinia ahagi LTYR-11Z new Erwinia ahagi strain is inoculated in the center of a detection culture medium, the culture medium is placed at 30 ℃ for culture, and whether a color change circle appears is observed. As shown in FIG. 5, after 3 days of culture on CAS detection medium, a clear yellow halo appeared around the lawn of this new species of Erwinia, indicating that it is able to produce siderophores.

8. The new Erwinia species of the invention has the inhibiting effect on wheat root rot fungi

Inoculating plant pathogenic fungi wheat root rot fungi on a PDA culture medium (200 g of potatoes, 20g of glucose, 15-20 g of agar and 1000mL of tap water), culturing at 30 ℃ for 2-3d, punching 1 fungus cake on the culture plate by using a puncher, transferring the fungus cake to the center of a fresh 1/4PDA culture plate, inoculating an activated Erwinia ahagiLTYR-11Z new strain to the edge of the same 1/4PDA culture plate, culturing at 30 ℃ for 2-3d, and observing the antagonistic effect of the strain LTYR-11Z on the wheat root rot fungi. As shown in figure 6, the new Erwinia species has a certain inhibitory effect on the plant pathogenic fungus, Rhizopus tritici.

9. The new Erwinia strains are inoculated to improve the resistance of wheat and Chinese cabbage seedlings to drought stress

Inoculating a single colony on an Erwinia ahagi LTYR-11Z plate of a new Erwinia ahagi strain into 5mL of TSB liquid culture medium, shaking the culture medium at 30 ℃ and 200rpm for 12h, transferring the culture medium into a triangular flask containing 200mL of TSB liquid culture medium, carrying out shake culture on the shaking table at 30 ℃ and 200rpm, achieving a logarithmic growth phase of the thalli after 24h, and centrifuging at 6000rpm to collect the thalli. The cells were washed twice with sterilized tap water and diluted to 10 deg.C⁸～10⁹CFU/mL is used as the biological agent.

Mixing vermiculite and soil according to a volume ratio of 1:3 to obtain a planting matrix, filling the planting matrix into strain bags, wherein each strain bag is 450g, sterilizing the strain bags at 121 ℃ for 25min after sealing, and then filling the sterilized mixed soil into a plastic flowerpot.

Selecting seeds of Jinmai No. 47 wheat with full and consistent seeds and Chinese cabbage seeds of four-season yellow seedling, soaking in 75% ethanol for 30s, pouring off liquid, and adding 0.1% HgCl₂Soaking wheat seeds for 7min (Chinese cabbage seeds for 3min), and then washing with sterile water for 5-6 times. Placing wheat seeds on sterilized wet double-layer filter paper, placing at 25 ℃, accelerating germination in the dark for 2d, transplanting full wheat sprouts with the same growth vigor into sterilized soil, wherein 3 seedlings are planted in each pot, and 40mL of sterilized tap water is poured; after the surfaces of the pakchoi seeds are disinfected, the seeds are directly planted in the sterilized mixed soil, one seed is planted in each pot, the three pots are repeated, and 20mL of sterilized tap water is poured.

Placing the prepared wheat pot plant in a greenhouse at 25 ℃, illuminating for 14h every day, pouring 30mL of sterilized tap water every other day, and after one week, pouring 40mL of the prepared Erwinia ahagi LTYR-11Z viable bacteria preparation (according to 10 per gram of soil)⁷～10⁸Inoculation of viable bacteria) is poured to the root position of wheat, and simultaneously a control group without inoculation is arranged for watering and killing40mL of post-sterilized tap water was repeated for each 3 pots of treatment. And (3) after about one week, waiting until the wheat grows to the period of two leaves and one heart, simultaneously carrying out drought treatment on the inoculation treated group and the non-inoculation control group, stopping watering for 12 days, recording the health state of wheat seedlings and taking pictures after the irrigation is recovered for 2 days, then harvesting plants, and measuring and counting growth indexes such as average root length, plant height, fresh weight, dry weight and the like of each treatment. Four sets of treatments for the wheat potting experiment are shown in FIG. 7, with the first pot from left to right being a wheat seedling that was neither inoculated nor drought-stressed, the second pot being an unaged but drought-stressed wheat seedling, the third pot being an Erwinia ahagi LTYR-11Z-inoculated and drought-stressed wheat seedling, and the fourth pot being an Erwinia ahagi LTYR-11Z-inoculated but not drought-stressed wheat seedling. As can be seen from FIG. 7, the wheat seedlings inoculated with the new species of Erwinia under the same drought treatment conditions (the third pot) keep fresh green and normal growth, while the wheat seedlings not inoculated with the Erwinia (the second pot) have withered and dwarf phenomena, i.e., the growth development and health status of the wheat seedlings inoculated with the new species of Erwinia under the drought treatment conditions are obviously better than those of the control not inoculated with the Erwinia. In FIGS. 8 and 9, CK and LTYR-11Z represent the drought treatment of wheat seedlings without inoculation and wheat seedlings inoculated with Erwinia ahagi LTYR-11Z, a new species of Erwinia ahagi, respectively. As shown in FIG. 8, the wheat seedlings inoculated with the new Erwinia species during drought treatment had an average increase in root length of 16.2% and an average increase in stem length of 20.2% as compared to the control inoculated with a different species of Erwinia. As shown in FIG. 9, the fresh weight of wheat seedlings inoculated with the new Erwinia species was increased by 86.1% compared to the non-inoculated control during drought treatment. The results of FIGS. 7, 8 and 9 show that under drought stress conditions, the biomass of wheat seedlings to which the Erwinia ahagi LTYR-11Z new species of Erwinia is applied is significantly increased, and the resistance to drought stress is significantly improved.

Placing the prepared plantula Brassicae chinensis in a greenhouse at 25 deg.C, illuminating for 14h every day, pouring 20mL of sterilized tap water every other day, and after three weeks, adding 20mL of Erwinia ahagi LTYR-11Z viable bacteria preparation (10 per gram of soil)⁷～10⁸Inoculating the number of viable bacteria) to the root of the Chinese cabbage, and keeping the number of viable bacteria in the Chinese cabbageThe inoculated control group was poured with 20mL of sterilized tap water, which was repeated for 3 pots of treatment. After about three weeks, the inoculated and non-inoculated control groups of the pakchoi are subjected to drought treatment at the same time, watering is stopped for 11 days, after 2 days of irrigation recovery, the health state of pakchoi seedlings is recorded and photographed, then the whole seedlings are harvested, and the average root length, the plant height, the fresh weight, the dry weight and other growth indexes of each treatment are measured and counted. As shown in FIG. 10, two drought treatments were performed in the Chinese cabbage potting experiment, wherein the first pot from left to right was a drought treatment of a Chinese cabbage seedling without inoculation of the microorganism, and the second pot was a drought treatment of a Chinese cabbage seedling inoculated with the Erwinia ahagi LTYR-11Z new Erwinia ahagi strain. As can be seen from FIG. 10, the seedlings of pakchoi inoculated with the new species of Erwinia (second pot) under the same drought treatment condition were kept fresh green and normally grown, while the seedlings of pakchoi not inoculated with the bacteria (first pot) were withered and dwarfed, i.e., the growth and health status of the seedlings of pakchoi inoculated with the new species of Erwinia under the drought treatment condition were significantly better than the control of the non-inoculated bacteria. In FIG. 11, CK and LTYR-11Z represent drought treatments of plantlets of Brassica napobrassica not inoculated with bacteria and plantlets of Brassica napobrassica inoculated with Erwinia new species Erwiniaahagi LTYR-11Z, respectively. As shown in FIG. 11, the fresh weight of the young pakchoi seedlings to which the live Erwinia new species preparation was applied was increased by 86.8% after drought stress treatment compared to the non-inoculated control.

The above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and any simple modifications or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the technical scope of the present invention are within the scope of the present invention.

Claims

1. An Erwinia strain for promoting crop drought resistance, which is characterized in that: the strain belongs to Erwinia, has a code of LTYR-11Z, is preserved in China center for type culture collection (CCTCCM 2016052) at 1 month and 18 days in 2016, and is classified and named as Erwinia alhagi of Alhagi;

the form and the culture characteristics are as follows: after culturing for 1d at 30 ℃ on an LB culture medium, the bacterial colony is yellow and semi-wet and convex; observing the strain cell by a transmission electron microscope to be rod-shaped and have a flagellum structure;

the 16S rRNA gene sequence of the strain is shown as SEQ ID NO. 1;

the sequence of the recA gene of the strain is shown as SEQ ID NO. 2;

the gpd gene sequence of the strain is shown as SEQ ID NO. 3;

the strain has the function of dissolving the insoluble inorganic phosphorus;

the strain is capable of producing indoleacetic acid;

the strain is capable of producing siderophores.

2. Use of an erwinia species according to claim 1 for increasing drought resistance in crops.

3. The use of an erwinia species for increasing drought resistance in crops according to claim 2, wherein said crops are wheat and cabbage.

4. Use of an erwinia species according to claim 1 for promoting the growth of a crop.