37 results about "Zoospore" patented technology

The invention belongs to the technical field of modern agriculture, and particularly relates to application of demethylzeylasteral (DZL) to preparation of a product for preventing and treating phytophthora. The invention determines the effect of pentacyclic triterpenoid demethylzeylasteral on activity inhibition of phytophthora capsici and other crop phytophthora, and demethylzeylasteral can inhibit phytophthora, sporangium release, zoospore germination and pathogenicity, which indicates that demethylzeylasteral (DZL) has the effect of resisting phytophthora capsici. Therefore, the compound provided by the invention can be used for preparing a small-molecule inhibitor for growth, development and pathopoiesis of phytophthora of crops, is expected to become a potential drug for resisting phytophthora of crops, and has good development and application values.

The invention discloses a method for cultivating kelp seedlings through diploid female gametophyte parthenogenesis, and belongs to the field of aquatic product engineering genetic breeding. And hybridizing the female and male single cell cloning lines of the induced protonema to obtain the tetraploid sporophyte. And the tetraploid sporophyte is mature and releases zoospores, diploid gametophytes are germinated and formed, and then male and female separation is performed to obtain diploid female gametophyte clone lines in batches. Under the culture condition provided by the invention, parthenogenesis of a diploid female gametophyte clone line is utilized for seedling culture. The diploid female gametophyte begins to ovulate after 6-7 days, and the ovulation time of the diploid female gametophyte is obviously earlier than that of haploid gametophyte in the same period and under the same condition. The 12-day ovulation rate reaches 86.5%, the 24-day sporophyte conversion rate reaches 98.3%, and most sporophyte forms are normal. In the seedling raising period, parthenogenesis seedling raising of the diploid female gametophyte is completed. The diploid female gametophyte can be used as a brand-new kelp germplasm material to be applied to kelp seedling cultivation.

The invention provides a streptomyces flavogriseus C-21 strain, which is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the registration number of the streptomyces flavogriseus C-21 strain is CGMCC No. 36050. The preparation method of the sterile fermentation filtrate of the streptomyces fulvus C-21 comprises the following steps: inoculating a strain C-21 to an oat culture medium plate in a streak manner, culturing for 7 days at 28 DEG C, scraping spores on the surface of the culture medium, adding sterile water to prepare a spore suspension with the concentration of 108 / mL, inoculating the spore suspension into a millet immersion culture solution according to the inoculum size of 2%, and culturing for 7 days at the temperature of 28 DEG C to obtain the sterile fermentation filtrate of the streptomyces fulvus C-21. Performing shaking culture for 7 days in a constant-temperature shaking table at the temperature of 28 DEG C and the speed of 180 r / min, centrifuging for 30 minutes at the speed of 12000 r / min, and filtering supernate by using a 0.22 mu m microporous filter membrane to obtain sterile fermentation filtrate. The streptomyces fulvus C-21 can generate extracellular enzymes such as cellulase, protease and amylase, sterile fermentation filtrate of the streptomyces fulvus C-21 can destroy mycelial morphology and cell membrane integrity of the tomato late blight bacteria, mycelial growth, sporangium germination and zoospore release of the tomato late blight bacteria are remarkably inhibited, and the streptomyces fulvus C-21 has a good control effect on the tomato late blight.

The application provides a kelp breeding performance evaluation method based on sporangium spore dissemination parameters and application, and belongs to the technical field of seaweed cultivation. The method comprises the following steps: S1, taking mature kelp samples, washing, and air-drying treatment to obtain pretreated kelp; S2, taking kelp tissue blocks from the pretreated kelp obtained in step S1, loading the kelp tissue blocks into a mesh bag, immersing the kelp tissue blocks in seawater, promoting the kelp tissue blocks to disseminate, and collecting zoospore liquid; S3, measuring sporangium spore dissemination parameters in step S2; S4, calculating dissemination capacity according to the sporangium spore dissemination parameters obtained in step S3, and evaluating the breeding performance of the kelp according to the dissemination capacity. The above method can quantify the sporangium spore dissemination characteristics of kelp, systematically evaluate the breeding potential of kelp, and improve the breeding efficiency and yield of kelp.

The invention relates to a strain of biocontrol and growth-promoting brevibacillus brevis LJQJ21 and an application of the strain of biocontrol and growth-promoting brevibacillus brevis LJQJ21 in prevention and treatment of plant oomycetes diseases, and belongs to the field of research and development of microbial pesticides. The Brevibacillus formis LJQJ21 has the capabilities of promoting growth and preventing diseases, has a relatively strong inhibition effect on mycelial growth of various pathogenic oomycetes (phytophthora capsici, phytophthora infestans, peronophythora litchii and pythium aphanidermatum) causing crop diseases, and can secrete pentapeptide antibacterial substances Edeine A and B, and the Edeine can remarkably inhibit germination of zoospores of the phytophthora capsici. In addition, the microbial agent taking the LJQJ21 spore fermentation bacterial liquid as a main active component has a relatively good prevention and treatment effect on fruit rot caused by phytophthora capsici. The Brevibacillus forts LJQJ21 has obvious growth promoting and disease preventing effects, is safe to human and livestock and environment-friendly, and has potential field application value and development prospect.

The invention discloses an agrobacterium tumefaciens-mediated genetic transformation method of Archeustochytrium cidebbufense, which comprises the following steps: firstly, inducing and collecting zoospore of Archeustochytrium cidebbufense; secondly, preparing agrobacterium tumefaciens containing a hygromycin resistance gene and a target gene plasmid; then, activating and inducing agrobacterium tumefaciens; creating a groove area on an induction culture medium plate, and co-culturing the zoospore and the induced agrobacterium tumefaciens in a groove; and finally, screening the Arteustochytrium limacinum transformant on a selective culture medium containing 25 mg / L of hygromycin, 200 mg / L of tiaculosporin and 300 mg / L of ampicillin. According to the invention, the efficient genetic transformation method of the Arteustochytrids cidebbuki is established for the first time, the method has the advantages of high transformation rate, stable inheritance and the like, an important technical means is provided for deeply researching the pathogenesis of the Arteustochytrids cidebbuki, and meanwhile, a foundation is laid for developing a new strategy for preventing and controlling microalgae diseases.

The invention provides application of rhizopus microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus It is found for the first time that the rhizopus microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Microsporus var. Moreover, the strain has the capabilities of producing cellulase, fixing nitrogen, decomposing inorganic phosphorus and producing siderophores, and pot experiments show that the strain can promote the growth of peppers. The invention provides a new way for biological prevention and control of pepper phytophthora blight, and has positive significance for reducing the use of pesticides and improving the yield and quality of pepper.

This invention discloses an oligosaccharide syltransferase STT3 subunit from *Phytophthora sojae*, its encoding gene, and its applications. The protein sequence of the oligosaccharide syltransferase STT3 subunit provided by this invention is shown in Sequence 2; its encoding gene is shown in Sequence 1. Experiments have demonstrated that the protein provided by this invention plays an important role in the growth and development of *Phytophthora sojae*, specifically manifested in the slowed mycelial growth, reduced number of sporangia and zoospores, and decreased pathogenicity of *Phytophthora sojae* after its deletion. These conclusions provide a technical basis for exploring the molecular mechanisms of *Phytophthora sojae* development and pathogenicity, and provide molecular targets for the future development of novel fungicides.

The invention discloses a pseudomonas strain JQ36 and a preparation method and application of a peptide compound produced by the pseudomonas strain JQ36. The pseudomonas JQ36 is separated from rhizosphere soil of wheat in Gansu province, and peptide substances with novel structures can be generated through liquid fermentation. The substances can be separated and purified by combining a solid-phase extraction technology with a high performance liquid chromatography technology to obtain monomeric compounds. Under in-vitro experiment conditions, the peptide substance can inhibit the zoospore germination of phytophthora capsici and split the zoospore of phytophthora capsici; in a pepper living body, the compound with the concentration of 50 mu M can well prevent and control phytophthora capsici diseases, and compared with a control group, the compound with the concentration can achieve the phytophthora capsici prevention and control effect of 83% or above. Therefore, the compound with the novel structure has a good phytophthora capsici prevention and control effect, can be used for preparing biological medicines for preventing and controlling phytophthora capsici, and has an important potential application value in the fields of agricultural production and the like.

The present invention discloses a strain of Pseudomonas and a preparation method and application of the non-ribosomal peptide produced thereby. The Pseudomonas HN8-3 of the present invention is isolated from the rhizosphere soil of Lens culinaris in Gansu Province and can produce pseudophomins A-D through liquid fermentation. These substances can be separated and purified into monomeric compounds by solid-phase extraction technology combined with high-performance liquid chromatography technology. Under in vitro experimental conditions, pseudophomins A-D at a concentration of 1 μM can well lyse the zoospores of Phytophthora capsici ( Phytophthora capsici ). On the living body of plants (cucumber leaves), the compounds at a concentration of 10 μM can well prevent and control the occurrence of diseases caused by Phytophthora capsici. Compared with the control group, this concentration can achieve a 100% effect in preventing and controlling Phytophthora capsici. Thus, it can be seen that pseudophomins A-D have a good effect in preventing and controlling Phytophthora capsici. Such lead compounds have the potential to be used as biological agents and biological drugs and can be used as the parent compounds of Pseudomonas-derived biological pesticides, having important potential application values in the fields of agricultural production and the like.

The invention discloses a glucosidase protein (GLS1) from phytophthora plant pathogenic oomycetes as well as a coding gene and application thereof. The PsGLS1 protein provided by the invention is a protein of which the sequence is as shown in SEQ ID No. 1 in Phytophthora sojae, and the PsGLS1 protein is a protein of which the sequence is as shown in SEQ ID No. 2 in Phytophthora sojae; the coding gene of the gene is shown as SEQ ID No.2. Experiments prove that the protein provided by the invention plays an important role in the growth and development process of phytophthora sojae, and after the PsGLS1 gene is knocked out, the mycelial growth rate, the sporangium number, the zoospore yield and the resting spore germination rate of the phytophthora sojae are obviously reduced, and the pathogenicity of pathogenic bacteria is obviously influenced. Glucosidase inhibitor mispermine has an inhibition effect on the growth of phytophthora sojae hyphae. In conclusion, the PsGLS1 gene has very high application value in control of epidemic disease occurrence and epidemic caused by phytophthora, and a molecular target is provided for research and development of novel bactericides in the future.

The invention provides an epiphytic system and an epiphytic method. The epiphytic device comprises a water tank with a bottom; an implantation member on which zoospore released from the mother algae can be attached; and a vertical light source capable of irradiating light toward the zoospore from below. The epiphytic device includes: a plurality of brightness detectors disposed above the bottomed water tank and capable of detecting a brightness distribution of the vertical light source; a distribution calculation means for calculating the three-dimensional distribution of zoospore on the basis of the brightness detection results of the plurality of brightness detectors; and a swimming control means that, on the basis of the three-dimensional distribution of the zoospores, controls the swimming of the zoospores so that the zoospores swim toward the bed.

This invention discloses a glucosidase protein (GLS1) from *Phytophthora*, a plant pathogenic oomycete, its encoding gene, and its applications. The PsGLS1 protein provided by this invention is effective against *Phytophthora soybean* (…). Phytophthora sojae The protein in this invention is shown in SEQ ID No. 1; its encoding gene is shown in SEQ ID No. 2. Experiments have demonstrated that the protein provided by this invention plays an important role in the growth and development of *Phytophthora soybeani*. PsGLS1 Gene knockout significantly reduced the mycelial growth rate, sporangium number, zoospore yield, and resting spore germination rate of *Phytophthora soybeani*, and also significantly affected the pathogenicity of the fungus. The glucosidase inhibitor sericite also inhibited the mycelial growth of *Phytophthora soybeani*. In summary, this invention… PsGLS1 Genes have high application value in controlling the occurrence and spread of diseases caused by Phytophthora, and provide molecular targets for the development of new fungicides in the future.

The invention relates to genetic breeding, in particular to a method for cultivating undaria pinnatifida triploid sporophytes by inducing homozygous diploid gametophytes. The method comprises the following steps: inducing homozygous 2n undaria pinnatifida sporophores to produce homozygous 2n gametophytes through spore-free propagation, and hybridizing the homozygous 2n gametophytes with common haploid (n) gametophytes to obtain undaria pinnatifida triploid (3n) sporophores; and determining the relative content of DNA in the nucleus of the hybrid sporophyte by using a flow cytometer, thereby identifying the ploidy of the chromosome as 3n. The 3n sporophytes are transplanted to the sea for cultivation, and the 3n sporophytes are identified to be incapable of releasing zoospores in the undaria pinnatifida seedling raising (breeding) season, namely infertile. The method can be used for cultivating a new variety of high-yield and high-quality undaria pinnatifida, and has important significance in developing genetic breeding and new variety creation research in undaria pinnatifida and even kelp brown algae.

The application discloses an oligosaccharyltransferase STT3A (staurosporine and temperature-sensitive A) subunit from Phytophthora capsici and a coding gene and application thereof. The oligosaccharyltransferase STT3A subunit provided by the application is shown as sequence 2; and the coding gene is shown as sequence 1. Experiments prove that the protein provided by the application plays an important role in the growth and development of Phytophthora capsici, and the specific performance is that after the protein is deleted, the mycelium growth rate of Phytophthora capsici is slowed down, the zoospore quantity is reduced, and the pathogenicity is reduced, etc. The above conclusion provides a technical basis for exploring the development and pathogenic molecular mechanism of Phytophthora capsici, and provides a potential molecular target for the research and development of a new type of bactericide in the future.

The invention discloses six kinds of microRNAs (microRNA, miRNA), namely miR2, miR3, miR8, miR53, miR117 and miR157 capable of regulating and controlling the development and pathopoiesis of Phytophthora capsici, and application of the six kinds of microRNAs, namely miR2, miR3, miR8, miR53, miR117 and miR157. The miRNAs have a ribonucleic acid sequence as shown in any of SEQ ID NO.1-6. The invention also discloses a preparation method of the miRNAs. The miRNAs involved in the invention can participate in the development and pathopoiesis of the phytophthora capsici, after the expression of the miRNAs is influenced, the capability of producing sporangium and zoospore of the phytophthora capsici is greatly reduced, the pathopoiesis capability is almost lost, and the miRNAs conservatively exist in different phytophthora capsici. The gene provided by the invention has a very high application value in preventing and treating crop epidemic diseases caused by phytophthora pathogenic bacteria such as phytophthora capsici, and the miRNAs are taken as targets to develop nucleic acid pesticides, so that the miRNAs have important significance in controlling the occurrence and prevalence of the crop epidemic diseases.

The invention discloses a gene PlP5CS1 and application of the gene PlP5CS1 in preventing and treating peronophythora litchii. According to the invention, a PlP5CS1 knockout vector is constructed, PEG-mediated protoplast transformation is carried out, and the gene PlP5CS1 is knocked out and back-supplemented from peronophythora litchii by using a homologous recombination method, so that a knockout mutant and a back-supplemented transformant are obtained. Compared with a wild type, the mutant has the advantages that the oospore yield is obviously reduced, and the pathogenicity of zoospore and hyphae is obviously reduced. The invention proves that PlP5CS1 is necessary for the growth and development and infection pathopoiesis of peronophythora litchii, is helpful for deeply illuminating the pathogenic molecular mechanism of peronophythora litchii, and provides a target gene for developing effective bactericides.

This invention discloses a multi-layer vertical seedling device and method for kelp. The seedling device includes a seedling frame and several layers of seedling trays. The height of the seedling trays is adjustable. A dynamic shading curtain is installed at the top of the seedling frame. A supplemental lighting unit, a flow control unit, and an environmental monitoring unit are installed on each seedling tray. Normal seedling cultivation is performed on the first layer of seedling trays. In the early stage of seedling attachment on the second layer of seedling trays, white light is emitted by the supplemental lighting unit of the second layer to promote the attachment and germination of zoospores to form gametophytes. Subsequently, the supplemental lighting unit of the second layer of seedling trays emits red and blue light, with the proportion of red light being greater than that of blue light. During the extended cultivation stage on the second layer of seedling trays, moderate light intensity red light is used as the main source and blue light as a supplement to slow growth while ensuring the accumulation of photosynthetic products, increasing the chlorophyll content of seedlings, enhancing adhesion, reducing diseases and seedling rot, and improving the stability and yield of seedlings.

The application provides application of chitin in early infection of plasmodiophora brassicae in prevention and control of brassica root tumour disease, and is based on the technology and application of blocking chitin synthesis of zoosporangium in early infection of plasmodiophora brassicae to prevent and control brassica root tumour disease. It is proved by experiments that the zoosporangium in early infection of plasmodiophora brassicae contains chitin, and the chitin is synthesized by plasmodiophora brassicae chitin synthase genes PbCHS3 and PbCHS7, thereby providing a new target for prevention and control of brassica root tumour disease. Through expression of PbCHS3 and PbCHS7 silencing vectors, exogenous small RNA treatment or application of polyoxin, which can block chitin synthesis, in arabidopsis and rape, brassica root tumour disease can be prevented and controlled efficiently, and key technology and method for prevention and control of brassica root tumour disease are provided.

The present invention provides the application of daidzin in preventing and controlling Phytophthora capsici. Daidzin can effectively inhibit the vegetative growth of Phytophthora capsici, and is expected to be used for preparing a new type of fungicide against Phytophthora capsici, reducing pesticide resistance and improving the control effect on Phytophthora capsici. In the application of daidzin in preventing and controlling Phytophthora capsici provided by the present invention, it has a certain inhibitory effect on three types of spores produced by Phytophthora capsici. Daidzin at a concentration of 1 μM - 5 μM can induce apoptotic-like death of the spores of Phytophthora capsici, and daidzin at a concentration of 7 μM - 15 μM can inhibit the release of sporangia of Phytophthora capsici and effectively inhibit the germination of zoospores of Phytophthora capsici. Using daidzin also helps to improve the disease resistance of susceptible varieties to Phytophthora capsici, which is simple, effective, green and environmentally friendly.

This invention belongs to the field of modern agricultural technology and specifically relates to the use of demethylzeylasteral (DZL) in the preparation of products for controlling Phytophthora spp. This invention demonstrates the inhibitory effect of pentacyclic triterpenoid demethylzeylasteral on the activity of Phytophthora capsici and other crop fungi. Demethylzeylasteral can inhibit the fungus, sporangium release, zoospore germination, and pathogenicity, demonstrating its anti-Phytophthora spp. activity. Therefore, the compounds provided by this invention can be used to prepare small molecule inhibitors of the growth, development, and pathogenicity of Phytophthora spp., demonstrating their potential as potential anti-Phytophthora spp. drugs and possessing promising development and application value.

The application discloses a gene PlCaMK1 and application thereof in prevention and treatment of litchi downy mildew, and belongs to the technical field of green prevention and control of crop diseases.The application applies a protoplast transformation technology based on polyethylene glycol and a CRISPR / Cas9 knockout strategy, constructs a PlCaMK1 knockout vector, and uses PEG-mediated protoplast transformation and a homologous recombination method to knockout the gene PlCaMK1 from litchi downy mildew, so as to obtain a knockout mutant.Compared with a wild type, the mutant has basically consistent growth rate, obviously weakened motility of zoospores, and significantly improved germination rate of chlamydospores.The application proves that PlCaMK1 is necessary for growth and development and pathogenic infection of litchi downy mildew.The research is helpful to further clarify the pathogenic molecular mechanism of litchi downy mildew, and provides a target gene for development of an effective fungicide.

The invention provides a seedling collecting method for improving the full-artificial seedling raising effect of undaria pinnatifida, and belongs to the field of economic seaweed seedling raising. According to the method, the blank undaria pinnatifida seedling curtain is placed in the seedling culture pond first, then the undaria pinnatifida sporophyll is placed for undaria pinnatifida seedling collection, the problems that in actual production, high-quality zoospores are lost, the seedling collection density is small, and the difference between seedlings attached to the seedling curtain placed first and the seedling curtain placed later is large are solved, more high-quality zoospores are collected on the seedling curtain, the seedling density is improved, and the survival rate of the seedlings is increased. Sporophytes of the undaria pinnatifida are uniformly distributed on different seedling curtains, so that the seedling quality is improved. The seedling collecting method provided by the invention can bring practical application value to the seedling raising work of the undaria pinnatifida, and the seedling raising effect of the undaria pinnatifida is improved.

The invention relates to germplasm preservation, propagation and seedling cultivation of undaria pinnatifida, in particular to a method for large-scale updating and rapid propagation of undaria pinnatifida gametophyte germplasm. Specifically, obtained mature homozygous double (DH) sporophytes are dried in shade and stimulated to diffuse a large number of zoospores, and the spores germinate to form gametophytes consistent with parent genotypes, so that large-scale updating and rapid propagation of gametophyte germplasm are realized. The method disclosed by the invention effectively solves the technical bottleneck that a large number of gametophyte clones are difficult to obtain in a short time due to slow cell division of gametophytes from single cells, and has important significance on creation of new undaria pinnatifida hybrid varieties and large-scale seed production.

This invention discloses an arginine methyltransferase protein from *Phytophthora* plant pathogenic oomycetes, its encoding gene, and its applications. The arginine methyltransferase protein provided by this invention is shown in sequences 6-8; its encoding gene is shown in sequences 1-3. Experiments have demonstrated that the protein of this invention plays an important role in the growth, development, and pathogenicity of *Phytophthora capsici*, a typical plant pathogenic oomycete. The absence or reduced expression level of this protein leads to slower mycelial growth rate, reduced sporangium production, decreased zoospore numbers, and reduced pathogenicity of *Phytophthora capsici*. Corresponding arginine methyltransferase inhibitors exhibit varying degrees of activity against typical plant pathogenic oomycetes such as *Phytophthora capsici*, *Phytophthora soybeani*, and *Phytophthora pathogenica*. The gene provided by this invention has significant application potential in the prevention and control of crop blight caused by *Phytophthora* plant pathogenic oomycetes. Novel fungicides developed based on this protein as a target have important practical significance for controlling the occurrence and spread of crop blight caused by *Phytophthora*.

To allow zoospores to efficiently settle to a settlement tool.SOLUTION: A settlement device 1 includes a bottomed tank 2, a settlement tool 3 on which zoospores Q released from a mother algae P can settle, and a vertical light source 5 capable of irradiating light from below toward the zoospores Q. The settlement device 1 includes: a plurality of brightness detectors 7 arranged above the bottomed tank 2 and capable of detecting the brightness distribution of the vertical light source 5; a distribution calculation unit 21 that calculates the three-dimensional distribution of the zoospores Q based on the brightness detection results of the plurality of brightness detectors 7; and a swimming control unit 22 that controls the swimming of the zoospores Q so that the zoospores Q swim toward the settlement tool 3 based on the three-dimensional distribution of the zoospores Q.SELECTED DRAWING: Figure 1

The invention discloses an FHA1 protein from Phytophthora spp. And an application of the FHA1 protein in screening of a protein-protein interaction (PPI) inhibitor. The amino acid sequence of the FHA1 protein is shown as a sequence 3. The protein can interact with phytophthora sojae 14-3-3 protein, and plays a key role in the production process of pathogenic bacteria sporangium and zoospore. By targeting the interaction between the FHA1 protein and phytophthora 14-3-3 protein, the interaction between the FHA1 protein and phytophthora 14-3-3 protein is inhibited so as to influence the normal life activity of phytophthora sojae, and the FHA1 protein can be used as a bacteriostatic or bactericide target for screening phytophthora bacteriostat or bactericide.

The present invention discloses a method for cultivating kelp seedlings using parthenogenesis of diploid female gametophytes, belonging to the field of genetic breeding in aquatic engineering. Female and male single-cell clones of induced conchoderma are hybridized to obtain tetraploid sporophytes. The tetraploid sporophytes mature and release zoospores, which germinate to form diploid gametophytes. Male and female gametophytes are then separated and batches of diploid female gametophyte clones are obtained. Under the culture conditions provided by the present invention, seedlings are cultivated using parthenogenesis of the diploid female gametophyte clones. These diploid female gametophytes begin to ovulate within 6 to 7 days, significantly earlier than the ovulation time of haploid gametophytes under the same conditions during the same period. The ovulation rate reaches 86.5% on day 12, and the sporophyte conversion rate reaches 98.3% on day 24. Most of the sporophytes have normal morphology. During the seedling cultivation period, the diploid female gametophytes complete parthenogenesis. The diploid female gametophytes can be used as a new kelp germplasm material for kelp seedling cultivation.

The present invention discloses CaKnot1-U5 protein and its application. The present invention discovered for the first time that the pepper phytophthora effector NLP779 induces pepper to produce antimicrobial peptides. The domain enrichment analysis of the up-regulated proteins in the TMT omics results was performed, and it was found that a class of Knot1 antimicrobial peptides were all up-regulated. When the exogenously purified Knot1 (i.e., CaKnot1-U5 protein) was added to the zoospores of pepper phytophthora, it was possible to inhibit zoospore activity, germ tube elongation, and appressorium formation. Spraying the pepper phytophthora effector NLP779 on pepper plants can induce an immune response in peppers and inhibit the infection of pepper phytophthora. The combination of NLP779 and CaKnot1-U5 can better prevent and control pepper phytophthora.