85 results about "Dauer larva" patented technology

The invention provides a spiropolyspora roseus strain for preventing and treating root knot nematode disease, and the preservation number of the spiropolyspora roseus strain is CGMCC No.41822. The invention also provides a microbial inoculum containing the spiropolyspora pink strain, and the microbial inoculum is prepared by the following steps: inoculating a culture medium with the spiropolyspora pink HLF-14-11, and culturing until spores are produced; spores are eluted to prepare a spore suspension, or a bacterial block is cut to serve as a liquid fermentation inoculant; inoculating the inoculant into a liquid culture medium, and carrying out shake culture; and taking the fermentation liquor to prepare liquid, powder and granules. The spiropolyspora pink strain provided by the invention is separated from root-knot nematode oocysts of diseased tomatoes, can parasitize eggs of root-knot nematodes and inhibit incubation of the eggs, fermentation filtrate of the spiropolyspora pink strain has a relatively strong poisoning effect on second-stage larvae of the root-knot nematodes, and the fatality rate of the second-stage larvae reaches 89.1%. Meanwhile, the strain can produce auxin substances such as indoleacetic acid and the like, and plant growth and root development are promoted.

The invention discloses interference engineering bacteria for blocking early infection of animal parasitic nematodes and application, and belongs to the field of animal parasitic disease prevention and treatment. According to the interference engineering bacteria disclosed by the invention, the HCON00038080 (cyp-22a1) gene of haemonchus contortus is specifically silenced by expressing double-stranded RNA (dsRNA), so that the biosynthesis of endogenous bile acid-like steroid hormone of the haemonchus contortus is inhibited, the activation of infectious larvae is influenced, and the infection establishment process of the infectious larvae is blocked. The invention can be used for preventing early infection of haemonchus disease of ruminants such as cattle, sheep, camels and the like and the phenomenon of spring / perinatal high tide, has higher application value for prevention and control of haemonchus disease, and has reference value for prevention and control of parasitic nematode disease of other animals.

The present invention provides a strain of Priestia aryabhattai HN02 and an application thereof, which is named as Priestia aryabhattai HN02 and has a deposit number of CGMCC NO. 28379. The strain has a good toxic effect on second-instar larvae and eggs of root-knot nematodes, is a biocontrol strain with high toxicity to plant parasitic nematodes, not only enriches the biocontrol bacteria resources of plant parasitic nematodes, but more importantly, has a very important significance for the development of green pesticides or fertilizers for killing nematodes.

The invention provides an arthrobotrys nematophila NPS044 strain, a biocontrol agent and application of the arthrobotrys nematophila NPS044 strain and the biocontrol agent, the arthrobotrys nematophila NPS044 strain is preserved in the China Center for Type Culture Collection on June 29, 2023, the preservation number is CCTCC M 20231144, the classification name is Arthrobotrys flagra NPS044, and the preservation address is Wuhan University, Wuhan, China. The strain is induced by nematode larvae to generate a three-dimensional viscous net to capture nematodes as nutrition of fungi so as to kill the plant nematode larvae, and also can generate some secondary metabolites in the growth process to partially inhibit egg incubation and kill nematodes, so that a certain stage of the nematode life history is blocked, and the nematode disease prevention and treatment effect is achieved. The chlamydospores of the arthrobotrys nematophila can be used for preparing wettable powder or liquid fermentation preparations and other preparations to prevent and control root-knot nematodes, and the preparation has a good shelf life.

The invention discloses nematode-killing streptomyces JXSY860 and application thereof, and belongs to the technical field of microbial pesticides. According to the invention, a new strain of Streptomyces turiscabs JXSY860 is found, the new strain of Streptomyces turiscabs JXSY860 has been preserved in Guangdong Microbial Culture Collection Center on August 8, 2024, and the preservation number is GDMCC No: 64998. The invention also discloses a preparation method of the Streptomyces turiscabs JXSY860. Through verification, the JXSY860 strain provided by the invention has stronger lethal activity on second-stage larvae of root-knot nematode, has stronger inhibition effect on incubation of root-knot nematode eggs, has important application value on prevention and control of root-knot nematode diseases of crops, and can be widely applied to preparation of biological agents for preventing and controlling the root-knot nematode diseases.

The invention relates to the technical field of prevention and control of microorganisms and nematodes, in particular to arthrobacter pastoris and application thereof. The arthrobacter pastoris disclosed by the invention is classified and named as Arthrobacter pascens, the strain number of the arthrobacter pastoris is YCH-T2, the arthrobacter pastoris is preserved in the China General Microbiological Culture Collection Center on March 19, 2024, and the preservation number of the arthrobacter pastoris is CGMCC No.30072. The strain has strong lethal activity on second-stage larvae of the root-knot nematode, has strong inhibition effect on incubation of eggs of the root-knot nematode, and has important application value in prevention and treatment of root-knot nematode diseases of crops.

The invention provides a method for preventing and controlling avocado bark beetle, and belongs to the technical field of avocado pest control, and the method comprises the following steps: removing damaged branches, arranging traps, and arranging pest sticking plates: arranging one bark beetle sticking plate on each plant which is freshly damaged by bark beetle, in the eclosion flying period of the adult trophy beetles in May to October every year, pesticide is mixed with water to conduct branch spraying, spraying is mainly conducted on newly-invaded plant branches, it is guaranteed that bark of the whole trunk is wet, spraying is conducted once every 15-20 days according to the harm situation, pesticide is continuously sprayed for 2-3 times, and punching and pesticide injection are conducted on the trunk; the method comprises the following steps of: after invasion of the small round chest bark beetles and in an active period of offspring larvae, injecting a pesticide into holes in trunks, injecting the pesticide once every 20-25 days, and continuously injecting for 2-3 times. Physical prevention and control are combined with chemical prevention and control measures, the number of beetle insects can be effectively reduced, and therefore the situation that beetle insects damage avocado fruit trees is reduced.

The invention provides dsRNA for preventing and controlling liriomyza sativae and a pesticide compound thereof, the pesticide compound is formed by mixing dsRNA and an SPc star-type cation nano-carrier according to the mass ratio of 1: 1, and a nano-platform is formed through self-assembly and is used for targeted delivery of double-stranded RNA (dsRNA). The compound provided by the invention can significantly reduce the degradation rate of dsRNA in a plant leaf surface environment, can penetrate through a plant leaf cuticle and enter mesophyll tissue, so that larvae latent in the leaf can intake the compound, and the dsRNA targeted to LtCht2 is designed to specifically cut LtCht2 mRNA through the RNA interference pathway effect in the larva body, so that chitin metabolism disorder is caused, and the expression of the LtCht2 in the larva body is inhibited. Therefore, normal pupation and eclosion of the larvae are blocked, and finally the purpose of controlling the population of the liriomyza clover is achieved.

The invention discloses application of an epidermal protein gene SlituCP26 in prevention and treatment of prodenia litura, and relates to the technical field of biology. The nucleotide sequence of the SlituCP26 gene is shown as SEQ ID NO: 1, the SlituCP26 gene is highly expressed in an indoxacarb resistant strain, dsRNA of the gene is prepared, the dsRNA is micro-injected into prodenia litura larvae, after injection, the expression level of the SlituCP26 gene is obviously reduced, the body type of the larvae is obviously reduced, the epidermis thickness is obviously reduced, and the sensitivity to indoxacarb is obviously improved. The invention also provides a SlituCP26 gene promoter, and the drug resistance of the prodenia litura can be detected through the difference in sequence after the promoter is amplified. According to the invention, the fact that the epidermal protein SlituCP26 gene participates in the effect of the prodenia litura on resisting insecticides and the formation process of a resistance mechanism is clear, and the epidermal protein SlituCP26 gene has theoretical significance on the development of new insecticides.

The invention discloses an application of a Brazilian strongylus FAR-1 protein as an anti-nematode drug target. A fluorescent ligand competitive binding experiment shows that the Japanese strongylus Brazil FAR-1 protein has the capability of binding various fatty acids and retinol; the Nbfar-1 gene is in high expression in the whole development stage of the Brazilian strongylus; nbfar-1 gene expression is inhibited through RNAi, the lipid content of larvae can be reduced, the adult egg laying rate, the egg hatching rate, larva development and adult epidermis formation are affected, and therefore growth and development of Brazilian strongylus are remarkably affected. Therefore, the Brazilian circular nematode FAR-1 protein can be used as a drug target for screening or identifying anti-parasitic nematode drugs, a method is provided for development of the anti-parasitic nematode drugs, and the Brazilian circular nematode FAR-1 protein has important significance on prevention and treatment of infection of parasitic nematodes.

The invention discloses a brevundimonas sp. Fermentation medium and application thereof in prevention and treatment of plant root-knot nematodes. Each liter of the brevundimonas chinensis fermentation medium comprises the following components by mass or volume: 6-10 g / L of yeast powder, 16-18 g / L of peptone, 31-45 ml / L of nematode lysis buffer, 0.8-2.5 g / L of chitin and 5.6-6 g / L of yeast extract, and the pH value of the brevundimonas chinensis fermentation medium is 6.5-6.8. The application of the fermentation broth culture medium refers to the application of the obtained fermentation broth in prevention and treatment of plant root-knot nematodes. According to the present invention, with the fermentation medium, the fatality rate of the obtained fermentation broth on the plant root-knot nematode exceeds 95%, the action time does not exceed 12 h, the nematode can be rapidly killed before the larva enters the plant, and the good application prospect is provided in the plant root-knot nematode prevention and control.

The application provides a Bacillus thuringiensis strain, and the preservation number of the Bacillus thuringiensis strain is GDMCC No. 67284. The lethal rate of the Bacillus thuringiensis strain provided by the application to second instar larvae of root-knot nematode reaches 98%, the control effect in a pot experiment reaches 60.07%, and the control effects on root rot and wilt are 66.79% and 63.23% respectively. The Bacillus thuringiensis strain is a bacillus isolated from rhizosphere soil, is safe to crops, and has control effects on root rot, wilt and root-knot nematode, and has the safety characteristics in agricultural application.

The present invention discloses a method for judging the influence of the environment on the development degree of chironomid larvae, including: setting a standard value for the area of the imaginal disc of chironomid larvae; calculating the experimental value of the area of the imaginal disc of at least one chironomid larva sample; and characterizing the development of the larvae based on the comparison between the experimental value of the area of the imaginal disc and the standard value of the area of the imaginal disc. The present invention characterizes the development of larvae based on the maximum area of the imaginal disc sections of chironomid larvae, and has the advantages of simple operation and short time consumption, and can further improve the indexes of ecological toxicology experiments with chironomids as model organisms.

The invention provides a screening method of entomopathogenic nematodes for preventing and controlling plagiospermus giganteus larvae in pine soil, and relates to the technical field of biology. The method comprises the following steps: collecting a plurality of entomopathogenic nematodes, and digging the larvae and peripheral soil of the platystigma obtusifolium as test materials; screening entomopathogenic nematode types by calculating the death rate and the corrected death rate of the larvae of the platystigma oblasioides; screening out two high-virulence pathogenic nematode strains, and testing the lethal effect of different doses of the high-virulence pathogenic nematodes on the larvae of the plagiospermus giganteus; testing the lethal effect of the screened high-toxicity pathogenic nematodes on the larvae of the plagiospermus giganteus in different soil layer thicknesses; the test data is analyzed, a conclusion is given, and an important basis is provided for preventing and controlling the larvae of the flat leaf bees by utilizing the entomopathogenic nematodes.

The application relates to the field of microbial technology and discloses a Pseudomonas asiatica HNHMPs-260 and application thereof. The strain is preserved in the Guangdong Microbial Culture Collection Center, and the preservation number is GDMCC No: 66854. Fermentation supernatant of the strain can prevent and treat root-knot nematode disease of Hami melon caused by Meloidogyne javanica. Experiments show that the fermentation supernatant has strong toxic effects on second instar larvae of root-knot nematodes and can significantly inhibit the hatching of egg masses and egg grains. In addition, the fermentation supernatant has good thermal stability and storage stability, and still maintains more than 80% nematocidal activity after high-temperature treatment at 121 DEG C and long-term storage at 4 DEG C. Meanwhile, the fermentation supernatant of the strain can promote the growth of Hami melon plants, improve physiological indexes such as root length, stem length, fresh weight and dry weight, and has the application potential of being developed into efficient, environment-friendly and multifunctional biological pesticides.

The invention relates to the technical field of gene engineering, in particular to a method for rapidly and economically carrying out gene function analysis on lepidoptera insects and application. The method comprises the following steps: designing four different sgRNAs by aiming at an exon region of a target gene, and constructing a sgRNAs synthetic primer mixing pool; 4 different sgRNA-DNA templates are synthesized at the same time, 4 different sgRNAs are further synthesized at the same time, and a sgRNAs mixed pool is formed; the sgRNAs-Cas9 protein and Cas9 protein are prepared into an sgRNAs-Cas9 compound, and the sgRNAs-Cas9 compound is microinjected into newly laid eggs; after the injected eggs develop into larvae, genome DNA is extracted, sgRNAs targeted areas are amplified, the mutation rate of target genes is determined through T7E1 enzyme digestion, and phenotype analysis is conducted on the larvae. According to the method, the mutation rate of the target gene is increased through redundant targeting of the four sgRNAs, so that functional analysis of the target gene is quickly realized in the G0 generation, and the research period of the gene function of the lepidoptera insects is greatly shortened. Besides, four different sgRNAs are synthesized at the same time by constructing a primer mixing pool of a plurality of sgRNAs, so that the economic cost for synthesizing the sgRNAs is greatly reduced.

The invention is suitable for the technical field of insect genetic engineering, and provides an HparGR22 gene and application thereof in establishing a phlorizin recognition in-vitro model. The DNA sequence of the HparGR22 gene is as shown in SEQ ID No: 1, and the coded amino acid sequence is as shown in SEQ ID No: 2. The gene has the highest expression quantity in the lower labial tassel of a holotrichia parallela larva, an oocyte injected with cRNA of the gene has obvious response to stimulation of phlorizin with different concentrations, it is clear that a product expressed by the HparGR22 gene can recognize phlorizin, and the function of the HparGR22 gene as the phlorizin receptor gene of the holotrichia parallela is determined. In view of the fact that the phlorizin recognition function of the gene is clear for the first time, a basis is provided for application of the gene in establishment of a phlorizin recognition in-vitro model, a foundation is laid for exploring the potential value of the gene in the field of gene engineering for preventing and controlling holotrichia parallela, and meanwhile a new direction is opened up for further research and application of the gene.

The invention relates to the field of insect prevention and control, in particular to a spodoptera frugiperda ABCC4 gene, application thereof and a method for preventing and controlling spodoptera frugiperda. The effect of the ABCC4 gene in the growth and development process of the spodoptera frugiperda is found for the first time, the death rate of larvae of the spodoptera frugiperda can be remarkably increased by inhibiting expression of the ABCC4, population development declines finally, a new thought is provided for controlling development of the population of the spodoptera frugiperda, and the application has a wide application prospect. And a basis is provided for realizing green prevention and control of spodoptera frugiperda and other lepidoptera insects. By applying an RNA interference technology, it is found that the death rate of larvae of spodoptera frugiperda is remarkably increased by inhibiting expression of the ABCC4 gene of the spodoptera In addition, the death rate of the larvae of the spodoptera frugiperda is obviously increased by spraying dsRNA of an interference sequence of the ABCC4 gene of the spodoptera frugiperda encapsulated by a nano material.

The invention relates to the technical field of molecular biological detection, in particular to a rapid detection primer group for bark beetle larvae and insect body fragments and application of the rapid detection primer group. According to the LAMP detection primer disclosed by the invention, the COI gene segment of the euphorbia leucopoda is used as a target gene for LAMP detection to design the LAMP detection primer, and the LAMP primer is high in specificity and high in sensitivity. On the basis, the invention provides the method for detecting the pachytous salicina, the rapid and accurate detection of the pachytous salicina in non-laboratory places such as ports and fields is realized by utilizing an LAMP technology, and the detection method has a wide application prospect.

The invention belongs to the field of identification of small gold moth, and particularly relates to a method for rapidly identifying ecotype of small gold moth. The method comprises the following steps: detecting the genotype of a Chr04.g05558 gene segment in a small gold moth genome, and determining the ecotype of the small gold moth according to the genotype; the Chr04. G05558 gene segment is located among Chr04: 51, 430, 521-51, 430 and 805 of the small gold moth, the Chr04. G05558 gene segment as shown in SEQ ID NO: 2 is a high mountain type small gold moth, and the Chr04. G05558 gene segment as shown in SEQ ID NO: 3 is a low mountain type small gold moth. The method disclosed by the invention can be used for identifying the ecotype of the small gold moth larva, is suitable for trace sample analysis, can directly interpret the result through conventional agarose gel electrophoresis, and can further judge the genotyping result through sequencing.

The present application relates to a kind of compound moxidectin pour-on and its preparation method and application, specifically to a kind of compound moxidectin pour-on, component mass mass fraction ratio includes: 0.1-5 portion moxidectin, 5-30 portion benzimidazole anthelmintic, 30-70 portion solvent, 5-20 portion solubilizer, 0.1-2 portion antioxidant, 10-30 portion transdermal enhancer.The present application not only covers gastrointestinal nematode, tapeworm, fluke and other various parasites, but also has killing or inhibiting effect on larva, worm egg, solve the problem of single component anthelmintic spectrum narrow, specific parasite effect is not good.

The invention discloses application of RNA (Ribonucleic Acid) interference on a hepialus armoricanus larva CYP18A1 gene in promoting transformation of cordyceps sinensis from bud spores to hyphae. In order to solve the problems of long artificial tending period, high cost and the like of cordyceps sinensis caused by slow rigidification process of hepialus armoricanus larvae infected by cordyceps sinensis, the siRNA synthesized by related genes (flash, larva of larvae of hepialus armoricanus LCP-30, 26-hydroxylase, isoform B and probe citase 3) acts on the hepialus armoricanus larvae, so that the cordyceps sinensis in hemolymph of the hepialus armoricanus is promoted to be converted into hyphae from blastospores, and the cordyceps sinensis in the hemolymph of the hepialus armoricanus is promoted to grow into the cordyceps sinensis in the hemolymph of the hemolymph of the hemolymph of the hemolymph of the hemolymph of the hemolymph. The result shows that the related gene of the hepialus armoricanus larva can significantly promote the two-form transformation of the cordyceps sinensis, so that the bombyx batryticatus rate of the bacterium-carrying hepialus armoricanus larva is improved.

The invention discloses Mortierella elongata and application of the Mortierella elongata, the strain number of the Mortierella elongata is JSAFC 247, the Mortierella elongata is preserved in the China General Microbiological Culture Collection Center on December 9, 2024, and the preservation number is CGMCC No.41703. The Mortierella elongata has the advantages that the Mortierella elongata can be used for preparing the Mortierella elongata and the application of the Mortierella elongata; the mortierella elongata strain provided by the invention is strong in pathogenicity to larvae of the larvae of the corpulenta aeruginosa, is environment-friendly and pollution-free, is not easy to generate drug resistance, can be used as a living body biopesticide, and has very strong application potential in biological prevention and control of the corpulenta aeruginosa.

The application discloses a kind of raw soil combined with fermentation liquor of aspergillus niger, and is the fermentation liquor obtained by fermenting aspergillus niger XO-2 on raw soil, specifically, aspergillus niger XO-2 is inoculated on raw soil to carry out fermentation, after fermentation, filtration, and the filtrate is the fermentation liquor of raw soil combined with aspergillus niger.The application separates and screens a strain of aspergillus niger from soil, and the fermentation liquor obtained by combining the aspergillus niger XO-2 with raw soil has a good toxic effect on second instar larvae of meloidogyne hapla chitwood, and can inhibit the hatching of eggs, which is of great significance for enriching plant parasitic nematode biocontrol bacteria resources and developing nematicidal plant and microbial source pesticides or pesticide fertilizers.

The invention discloses application of an RAD9A gene as a target spot in preparation of a preparation for preventing and treating insects. The RAD9A gene of the plutella xylostella is knocked out by utilizing a CRISPR-Cas9 technology, and four kinds of homozygous mutants are obtained through screening. Wherein most of homozygous mutant embryos are lethal, and cavities of surviving homozygous mutant larva testis are increased and fused, and structural deformity such as whole atrophy of the testis occurs. Development of progenies of the surviving homozygous mutants is delayed, and the progenies finally die According to the invention, a UAS-GAL4 system is utilized to construct a fruit fly strain of specific RNAi RAD9A in a testis. Reduction of RAD9A expression can obviously cause apoptosis of drosophila larva testis cells, which indicates that RAD9 has a conservative function in insect testis development. Based on the ORF sequence conservative property of the insect RAD9A, the mutation of the region can be used as a control target of various pests. Based on the CRISPR-Cas9 technology, the RAD9A knockout target spot designed in the invention can play a similar effect on the lepidoptera insects.

The application discloses a bacillus licheniformis-derived nematocidal peptide Peptide-1 and application of the nematocidal peptide Peptide-1 in the prevention and control of root-knot nematode diseases, wherein the amino acid sequence of the nematocidal peptide Peptide-1 is shown as SEQ ID NO. 1. The application further provides a medicament for preventing and controlling root-knot nematodes and a prevention and control method thereof. The activity verification result shows that under the condition of 1.00 mmol / L, the corrected mortality of the nematocidal peptide Peptide-1 to the second instar larvae of root-knot nematodes reaches 90.7% after 24 hours, and the nematocidal peptide Peptide-1 has a clear and efficient lethal effect and concentration dependence. The nematocidal peptide Peptide-1 can be used for the green prevention and control of root-knot nematodes and the creation of new germplasm resources of root-knot nematode-resistant crops, meets the requirements of green agricultural development, and can effectively solve the problems of pesticide residues, drug resistance and ecological pollution caused by traditional chemical nematocidal agents.

The invention provides a device for repelling longhorn beetle larvae in a trunk by using a high-voltage electric shock principle, which comprises a power supply connected with a high-voltage generator through a connecting wire; a frequency adjusting knob is mounted on the high-voltage generator, the high-voltage generator is respectively connected with the electrode probe and the loop electrode through connecting wires, a control switch is mounted on the connecting wire of the high-voltage generator and the electrode probe, and the electrode probe and the loop electrode are inserted into a tree trunk during use. High-voltage electric shock directly acts on insect channels in trunks, current penetrates through xylem, accurate electric shock killing of longhorn beetle larvae is achieved, the defects that chemical pesticides are difficult to permeate the trunks and do not act directly are overcome, the prevention and treatment efficiency is remarkably improved, and the prevention and treatment cost is reduced. And the problems of insufficient ultrasonic penetrating power, inapplicable power grid structure and the like in the prior art are solved.

The invention discloses application of RNA (Ribonucleic Acid) interference on a hepialus armoricanus larva LCP-30 gene in promoting conversion of cordyceps sinensis from bud spores to hyphae. In order to solve the problems of long artificial tending period, high cost and the like of cordyceps sinensis caused by slow rigidification process of hepialus armoricanus larvae infected by cordyceps sinensis, the siRNA synthesized by related genes (flash, larva of larvae of hepialus armoricanus LCP-30, 26-hydroxylase, isoform B and probe citase 3) acts on the hepialus armoricanus larvae, so that the cordyceps sinensis in hemolymph of the hepialus armoricanus is promoted to be converted into hyphae from blastospores, and the cordyceps sinensis in the hemolymph of the hepialus armoricanus is promoted to grow into the cordyceps sinensis in the hemolymph of the hemolymph of the hemolymph of the hemolymph of the hemolymph of the hemolymph. The result shows that the related gene of the hepialus armoricanus larva can significantly promote the two-form transformation of the cordyceps sinensis, so that the bombyx batryticatus rate of the bacterium-carrying hepialus armoricanus larva is improved.

The application discloses an application of a nuclear receptor target gene in preparation of a biological preparation for blocking activation of diapause larvae, and relates to the field of biotechnology and parasite prevention and control. According to two nuclear receptor targets of Haemonchus contortus HCON_00101910 (regulating activity of worms) and HCON_00023750 (regulating development of larvae), the two nuclear receptor targets are combined with host progesterone and estradiol and are activated, constitute a key signal path in the spring activation process of diapause larvae, and have no homologous genes in mammals, and the safety is excellent. By constructing specific shRNA lentivirus vectors (the silencing efficiency is all greater than or equal to 60%) targeting the two genes, single target or double target synergistic intervention is realized, and the activity-development double key links of worms in the host body can be specifically blocked. The application provides a new paradigm of preventive prevention and control with high specificity and green safety, and provides core technical support for solving the seasonal epidemic problem of blood fluke disease.

A method for screening tobacco resistance against root-knot nematode based on intensive seedling production is provided. The method has two biological properties: inducing and stimulating the hatching of nematode eggs by host root exudates, and easily infecting the root cap elongation zone by hatched second-instar larvae. The second-instar larvae hatched by the root-knot nematode eggs are continuously inoculated. After that, under cultivating the infected tobacco seedlings in shallow water infiltrating and humidifying substrate, the created temperature, humidity and air permeability conditions are suitable for disease induction. After disease investigation, disease index is calculated, and the resistance of tested cultivars is evaluated according to the disease index. The method features simple operation, high selection efficiency, and high accuracy and reproducibility.