215 results about "Stripe rust" patented technology

The invention belongs to the technical field of molecular breeding, and provides an SNP molecular marker linked with a wheat stripe rust resistance gene QYr.sicau-1B.1 and application thereof. The SNPmolecular marker is KASP-Yr, which can be obtained by amplifying a primer having a nucleotide sequence as shown in SEQ ID NO.1-3. Detection analysis indicates that the molecular marker can be used for accurately tracking wheat stripe rust resistant QTL QYr.sicau-1B.1 and predicting the stripe rust resistance characteristics of wheat, so that molecular designed breeding can be performance conveniently. The invention further discloses a method for identifying the molecular marker linked with wheat stripe rust resistance QTL QYr.sicau-1B.1. By utilizing the method, the stripe rust resistance prediction accuracy can be reinforced to quickly screen wheat variety or strain with stripe rust resistance for breeding, the breeding process for high-yield variety of wheat can be greatly accelerated.

The invention provides a breeding method for the germ plasm of a new translocation line wheat-rye T2BL.1RS, which is characterized in that, distant hybridization is performed by taking common wheat variety Xiaoyan 6 as female parent and relative plant rye variety German White as male parent; seeds are acquired after immature embryo salvation culture, colchicine half root soaking method and chromosome doubling; backcross seeds are acquired after disease resistance identification, cytological identification and backcrossing utilizing the original parent Xiaoyan 6 as male parent; then after disease resistance identification and cytological identification, individual plants with excellent comprehensive characters are selected in direction for self crossing, and after continuous self cross selective breeding for six generations, the finally acquired individual plant is confirmed to be wheat-rye T2BL.1RS translocation line after identified by continuous total genome in situ hybridization and three-probe multicolor fluorescence in situ hybridization. The breeding method for the germ plasm of a new translocation line wheat-rye T2BL.1RS has the advantages that, the wheat-rye T2BL.1RS translocation line has high resistance to stripe rust, current prevalent fungus strain, powdery mildew and other important virus strains; the invention has excellent high yield character; the method lays an excellent germplasm base for the cultivation of breakthrough new wheat variety with disease resistance and high yield.

Disclosed herein is a method for increasing the production of crops, particularly wheat and soybean, using herbicide resistant cultivars. In one aspect of this method, the method increases crop yield by diminishing the impact of the root diseases caused by Gaeumannomyces and Rhizoctonia species by treating the crop with an herbicide, in particular glyphosate. In another aspect the method for treating crops reduces the effects foliar pathogens and diseases, particularly fungal pathogens, such as rusts, including soybean rust, stem rust, stripe rust and leaf rust.

The invention discloses a wheat stripe rust predicting method based on a particle swarm and a support vector machine. The method comprises the steps that a stepwise regression method is used for carrying out effective dimension reduction on a high-dimensional sample firstly to eliminate redundancy and reduce the influence of incoherent factors on a forecast object; then the advantages that a PSO algorithm is not likely to fall into local minima, simple in algorithm and small in calculation amount are utilized for optimizing the kernel function parameter g and the penalty factor C of the support vector machine, and an optimal prediction model is obtained fast and efficiently. The method is based on a stepwise regression, PSO and SVM mixed algorithm, wheat stripe rust is accurately and stably predicted and forecast, and a scientific basis is provided for earlier prevention and treatment of wheat stripe rust.

The invention discloses an auxiliary screening method for rust-disease-resistance wheat and its special primers. The invention provides a PCR reagent for the auxiliary screening of rust-disease-resistance plants, comprising a primer pair composed of primers with nucleotide sequences of SEQ ID No:1 and SEQ ID No:2 in the sequence table and a PCR amplification buffer. The invention provides a novelmajor effect gene site QYr.caas-2BL and SSR primer Xgwm501 of the auxiliary screened rust-disease-resistance wheat of the site, the mark can accurately identify the rust-disease-resistance gene QYr.caas-2BL. The special primers and molecular markers provided by the invention can play an important role in breeding of wheat for disease resistance.

The invention discloses a design method of an SSR label primer. In order to overcome the defect of insufficient polymorphism of the conventional SSR label primer, the invention provides a method for designing a novel SSR label primer based on a draft sequence of a genome. The design method comprises the following steps: firstly selecting an SSR label primer with a known site as a starting SSR label primer; secondly, comparing the starting SSR label primer with the draft sequence of a chromosome to which the starting SSR label primer belongs, and finding a contig in a comparison result; thirdly, searching an SSR sequence in the contig as a finishing SSR sequence; finally, designing the SSR label primer based on the finishing SSR sequence. The invention provides 14 pairs of novel SSR label primers related to wheat stripe rust resistance, and a method for establishing a wheat genetic map with L693*L661 and L661*L693F2 single plants as a mapping population, wherein five pairs of the SSR label primers generate genetic polymorphism in a genetic test group. According to the design method, the number of the SSR label primers with known sites can be quickly increased and the polymorphism of the SSR label is increased; the genetic map can be quickly encrypted through combination with initial gene localization.

The invention relates to a regional scale wheat stripe rust monitoring method based on a remote sensing image red-side waveband. Compared with the prior art, the regional scale wheat stripe rust monitoring method solves the defect of poor wheat stripe rust remote sensing monitoring precision. The method comprises the following steps: acquiring and preprocessing a remote sensing image; screening primarily selected characteristic factors; constructing a wheat stripe rust severity monitoring model; training a wheat stripe rust severity monitoring model; and judging the severity of the regional scale wheat stripe rust. According to the invention, Sentine-2 is used tocarry out inversion on the remote sensing image to obtain a broadband vegetation index feature and a red-edge vegetation index feature related to the disease, and the Relief FF and K-means algorithm to screen a broadband vegetation index feature set which is relatively high in disease correlation and relatively low in redundancy and a feature set with added red-edge vegetation indexes, and a wheat stripe rust severity monitoring model is established with a BPNN algorithm, so as to realize monitoring of the wheat stripe rustseverity on a regional scale.

The invention relates to a single tube nested PCR (polymerase chain reaction) detection method for wheat stripe rust bacteria and a primer thereof. The method comprises the following steps: in a single PCR reaction tube, finishing the nested PCR amplification once by an inner pair and an outer pair of wheat stripe rust bacteria specific primers; and judging that wheats or unknown pathogen spores to be detected are wheats infected by the wheat stripe rust bacteria or the wheat stripe rust bacteria by a target segment, wherein the sequences of the nucleotide residues of the inner pair and the outer pair of wheat stripe rust bacteria specific primers are disclosed in SEQ ID No.1, 2, 3 and 4. The method disclosed by the invention has good specificity, is simple and easy to realize, and can beused for early detection for field wheat stripe rust and used for monitoring diseases, and the detection sensitivity is 20fg.

Secale cereale L is one of the important kindred plants of wheat and has the characteristics of floweriness, multi-powder, eurytopicity, and the like. The 1RS segment of secale cereale L carries resistance genes Lr26, Sr31, Yr9 and Pro8 for resisting leaf rust, stem rust, stripe rust and powdery mildew as well as plant hopper resistant gene Gb2 and a great amount of anti-retrieval genes. The content of soluble fiber of 1BL / 1RS translocation wheat flour is higher than that of ordinary wheat and is beneficial to human body. Related genes of a plurality of excellent traits for increasing the QTL loci, improving the yield traits and increasing the protein content exists on the 1RS. Me1z, Schlegel and Thiele find that partial isogeny relationship exists between 1RS, 1RL, 2RL, 3RS and 5RS and corresponding wheat chromosome arms via ph16 line analysis of addition line, telomere line and the wheat, thereby being capable of producing abnormal addition line, replacement line and translocation line of wheat-secale cereale L. As 1RS can favorably compensate negative effect caused by 1BS defect on the heredity, the wheat 1B / 1R translocation line can be directly applied to wheat breeding. The researched is carried out based thereon.

The invention discloses a filtration assisting method of yellow rust resistant wheat varieties and a specific primer. A filtration assisting primer pair of yellow rust resistant wheat varieties that is provided by the invention consists of a DNA that is shown in sequence 1 of the sequence table and a DNA that is shown in sequence 2 of the sequence table. The filtration assisting method of yellow rust resistant wheat varieties that is provided by the invention comprises the following steps: a genomic DNA of a wheat variety to be detected is used as a template, the primer pair is used for PCR augmentation, an augmented product is detected, and the wheat variety to be detected with a 343bp strip in the augmented product is yellow rust resistant wheat candidate. The invention further provides a molecular marker of a yellow rust resistance gene YrZH8 that is a DNA shown in sequence 3 of the sequence table. The molecular marker has closer linkage with YrZH84 and consequently has high efficiency in the breeding of yellow rust resistant wheat molecules and the cloning of the yellow rust resistance gene YrZH84. The primer pair and the molecular marker of the invention have important actions in the breeding of yellow rust resistant wheat varieties.

The invention discloses a method for screening a wheat variety with stripe rust resistance assisted by molecular markers and special primers used therein. Sequences of the primer pairs provided in the invention for assisted selection of a wheat variety with stripe rust resistance are described in a primer sequence table (Table 1). The method for assisted selection of a wheat variety with stripe rust resistance provided in the invention is carried out on the basis of conventional breeding and causes no interruption to the breeding process of a breeder except that in the generations of F2 and F6, after the selection of the breeder, candidate individual plants are subjected to molecular marker detection and only those individual plants containing two stripe rust resistant genes are reserved,thereby helping the breeder to more effectively select excellent strains containing a plurality of stripe rust resistant genes and enhancing endurance of stripe rust resistance of the strains. According to the invention, a novel stripe rust resistant gene Yrcaas and its special primers are discovered in the wheat variety Zhou 8425B; the gene is on wheat 1B chromosome and is located between SSR mark Xbarc8 and SSR mark Xgwm582, wherein the two marks can be used for assisted breeding of stripe rust resistant plants. The special primers of the stripe rust resistance genes in the invention are important to the breeding of stripe rust resistant wheat.

A wheat stripe rust germina molecule testing method, that is: the differential probe (the upsteam primers: 5'-TCTGTAAGATGTTAGATGC and the downsteam primers 5' -ATGCTGGCAGTGTGGTTG), expands by PCR (the expending parameter 94 centigrade pre-denaturalization 3min; then 94 centigrade denaturalization 50sec, 54 centigrade annealing 90sec 72 centigrade extends 2min, altogether 35 circulations; 72 centigrade extends 10min), the gelose gelatin electrophoresis, tests the disease-carrying situation of the wheat by the expanding production. The invention is used for forepart inspection of wheat stripe rust disease situation during winter and spring, provides the reliable technical support and the theory basis for the wheat stripe rust disease preventing and controlling decision-making.

The invention discloses application of an Ae.tauschii ssp.strangulata Yr4DS gene to stripe rust resistant breeding of wheat plants. A novel wheat stripe rust resistant gene Yr4DS is cloned from Ae.tauschii ssp.strangulata for the first time, and the sequence of the gene is shown as SEQ ID NO.1, SEQ ID NO.3, SEQ ID NO.5, SEQ ID NO.7, SEQ ID NO.9 or SEQ ID NO.10. The gene can effectively regulate and control the stripe rust resistance of wheat, and enriches the gene resources of wheat stripe rust resistance. The expression of the Yr4DS is found to be capable of providing a high-level stripe rustresisting function, indicating that the man-made manipulation of the Yr4DS gene can endow wheat and other wheat plants with resistance to stripe rust. By means of Yr4DS gene-based molecular mark assistant breeding, genetic transformation and gene editing, the resistance level of wheat and other wheat plants to stripe rust can be improved, and intermediate materials and production varieties capable of resisting stripe rust can be cultured and created.

The invention discloses a Bacillus sp. E1R-j, which is preserved in China General Microbiological Culture Center of Microbial Culture Collection Management Committee on August 16th, 2007 with the preservation number of CGMCC No.2134; the invention further discloses a strain separating and identifying method, a thallus preparation method and a preparation method of an antimicrobial active substance, as well as applications of the E1R-j strain, the thallus and the antimicrobial active substance of the strain in controlling diseases including wheat take-all, Blumeria graminis and wheat yellow stripe rust as well as promoting seed germination and growth of wheat. The E1R-j strain is obtained from wheat root, has simple screening method, convenient operation, stable product quality, environmental protection and remarkable effects on controlling wheat take-all, Blumeria graminis and wheat yellow stripe rust, and does not have toxic side effect.

The invention discloses molecular marker for wheat stripe rust disease-resistant new gene Yr50 assisted selection and a using method thereof, belongs to the technical field of plant molecular genetics and wheat germplasm innovation and relates to a molecular marker for a wheat stripe rust disease-resistant new gene and a positioning method of the molecular marker. The molecular marker for wheat stripe rust disease-resistant new gene Yr50 assisted selection consists of a marker Xbarc1096 and a marker Xwmc310, wherein the genetic distance between the marker Xbarc1096 and a wheat stripe rust resistance gene Yr50 is 6.9cM and the genetic distance between the marker Xwmc310 and the wheat stripe rust resistance gene Yr50 is 7.2cM. The wheat stripe rust disease-resistant new gene Yr50 which is originated from Thinopyrum is discovered for the first time in the world and the molecular marker which is linked with the wheat stripe rust disease-resistant new gene Yr50 is obtained. By using the wheat stripe rust molecular marker assisted breeding method provided by the invention, the selected targets are clear and the cost can be saved. Not only can a new resistant resource be provided for wheat stripe rust disease-resistant breeding, but also material and technical foundations are laid for map-based cloning of the gene.

The invention discloses a composition of clorine-nalidixic-methyl and azole bactericides, the medical ingredients of which consist of the clorine-nalidixic-methyl and the azole bactericides. The composition has good and obvious bactericidal effect in preventing and treating crop diseases such as powdery mildew, banded sclerotial blight, stripe rust, root rot, rice blast, large and small leaf spot of corns, downy mildew, gray mold and sclerotinia, etc.

The present invention discloses method of screening out stripe rust resisting wheat and its special primer. The primer for screening out stripe rust resisting wheat includes the first primer pair comprising the nucleotide sequences of the sequence No. 1 and the sequence No. 2 and the second primer pair comprising the nucleotide sequences of the sequence No. 3 and the sequence No. 4 in the sequence list. The method of screening out stripe rust resisting wheat includes adopting the genome DNA of the tested wheat as template, performing PCR amplification under the guidance of the first primer pair and screening out amplified product with band of 265 bp size, performing PCR amplification under the guidance of the second primer pair and screening out amplified product with band of 238 bp size as the stripe rust resisting wheat variety. The SSR marks Xcfa2040 and Xbarc32 have the linkage distances of 1.4 cm and 4.8 cm separately. The present invention is significant in screening disease resisting wheat variety.

The invention discloses a wheat stripe rust resistance gene yrZ15-1370 as well as a molecular marker and application thereof. The wheat stripe rust resistance gene yrZ15-1370 is located on a long armof a 6A chromosome of wheat, and the physical position of the wheat stripe rust resistance gene yrZ15-1370 in a RefSeqv1.0 genome version is 601.47 Mb and 603.30 Mb. The SNP site of the molecular marker is located in the interval of yrZ15-1370, the polymorphism is A / G, and the molecular marker can accurately track the wheat stripe rust resistance gene yrZ15-1370. The invention further discloses aprimer group for identifying the wheat stripe rust resistance gene yrZ15-1370, the primer group provided by the invention can be used for rapidly screening out a wheat variety or strain with the wheatstripe rust resistance gene yrZ15-1370 for breeding, and the breeding process of a wheat disease-resistant variety can be greatly accelerated.

The invention relates to the fields of agricultural biotechnical engineering and wheat disease resistance genetic breeding, and in particular relates to a molecular marker interlocking with a wheat stripe rust resistant gene, an acquisition method and application thereof. The marker interlocking with the wheat stripe rust resistant gene is obtained through amplification by degenerate primers: an upstream primer 5-'AAGTGGAACAAGGTTACG-3', and a downstream primer 5'-GGIGGIGTIGGIAAIACIAC-3'. The marker can be used to assist selective breeding of wheat stripe rust resistance, and overcome the shortcomings in wheat stripe rust resistance identification in conventional breeding, such as vulnerability to environment impact, poor stability and repeatability, heavy workload, time and labor consumption and long breeding cycle, so as to speed up the breeding process of a wheat stripe rust resistance variety.

The invention discloses a primer combination assisting in screening stripe-rust-resistant wheat and an application of the primer combination. The primer combination comprises an Xwmc382 primer pair and an Xgwm636 primer pair, wherein the Xwmc382 primer pair comprises single-chain DNA (deoxyribose nucleic acid) molecules shown in a sequence 1 in a sequence table and single-chain DNA molecules shown in a sequence 2 in the sequence table; the Xgwm636 primer pair comprises single-chain DNA molecules shown in a sequence 3 in the sequence table and single-chain DNA molecules se shown in a quence 4 in the sequence table. The primer pair and molecular marks can be used for breeding of stripe-rust-resistant wheat molecules and cloning of stripe-rust-resistant genes. The special primers and the molecular marks play an important role in breeding of disease-resistant wheat.

The invention relates to a pesticide composition containing prothioconazole and triazoles, which comprises active ingredient A and active ingredient B, wherein active ingredient A is selected from prothioconazole, and active ingredient B is selected from diniconazole, One of myclobutanil, wherein the weight ratio of active ingredient A to active ingredient B is 80:1 to 1:80, made into wettable powder, water dispersible granule, suspension, suspoemulsion, water emulsion, microemulsion , used to control powdery mildew, sheath blight, fusarium wilt, leaf spot, rust, sclerotinia, net spot, gray mold, black spot, brown spot, scab, white rot, leaf rust , stripe rust, glume blight, leaf mold and other diseases, it has the characteristics of small dosage, resistance to rain erosion, and obvious synergy.

The invention discloses a wheat stripe rust resistance related protein TaNAC3 and coding gene and application thereof. The wheat stripe rust resistance related protein is A1) or A2): A1 is the proteinwith an amino acid sequence of sequence 2; A2) substitutes and / or removes and / or adds one or more amino acid residues to the amino acid shown in the sequence 2 in a sequence table and has the proteinwith the same functions of the protein shown the sequence 2. Experiments prove that the disease resistance on stripe rust of plants can be reduced after the coding genes of the stripe rust resistancerelated protein are interfered so that a transgenic plant with reduced stripe rust resistance can be obtained to be taken as a model plant for screening plant stripe rust resistance medicines. The stripe rust related protein and the genes thereof have significant meaning on culturing stripe rust resistance plants and are suitable for popularization and use.

The invention belongs to the technical field of wheat gene detection, and particularly relates to chain KASP molecular markers, primers and application of a wheat anti-yellow-rust main-effect site gene QYr.nwafu-6BL.2. The molecular markers include the molecular marker KASP-630 and the molecular marker KASP-162. By using the two molecular markers in cooperation, the prediction accuracy of the yellow rust main-effect site QYr.nwafu-6BL.2 is up to 98%.

The invention relates to the development and application of a bacteria and pest killing compound agent for wheat. The compound agent mainly consists of tebuconazole, triazolone and imidacloprid and can be prepared into missible oil, missible oil, wettable powder and the like. Demonstrated by biological test, the compound agent has obvious synergistic function for wheat stripe rust and erysiphe graminis and can also prevent and kill aphid. According to field experiments, the compound agent can achieve 90 percent of effect in preventing wheat leaf diseases, more than 90 percent of effect in preventing the erysiphe graminis, no less than 98 percent of effect in preventing and controlling wheat sitobion avenae. The compound agent has the functions of killing bacteria and pests, is conveniently used, saves work time, reduces cost and environment pollution, and actively responds to the national policy of energy conservation and emission reduction. Meanwhile, the compound agent has simple process, is easy to produce, can be directly transformed into a production capability and can obtain economic and social benefits as soon as possible.

The invention relates to the fields of plant genetics and wheat breeding, in particular relates to a molecular marker for a wheat anti-stripe rust character, namely a wheat anti-strip rust gene Yr69 as well as a linked SSR molecular marker and an application method thereof, and aims at solving the problems that genetic distance between an existing molecular marker and the anti-strip rust gene Yr69 is long and marking is not accurate enough. The application method comprises the following steps: 1) amplifying by taking wheat DNA as a template and 2SA33 as a primer; 2) sequentially carrying out pre-degeneration, degeneration, annealing, extending, cycling, extending, and storing for later use; 3) carrying out electrophoresis, then mixing electrophoresis products with a loading buffer solution, then carrying out sample application, carrying out electrophoresis, and then dyeing and photographing; and 4) determining that Yr69 exists if a specific stripe is amplified. The invention has the advantages that firstly, the 2AS33 is obtained; and secondly, a dominant marker is adopted, the genetic distance is 1.9cm, the Yr69 gene is rapidly and accurately identified, powdery mildew resistance is predicted, and utilization of Yr69 is promoted.

The present invention provides wheat cultivars that are resistant to leaf rust and / or stripe rust disease caused by strains of the fungus Puccinia and to means and methods for producing same. Particularly, the present invention provides wheat cultivars comprising a chromosome segment of Ae. sharonensis, the chromosome segment confers, enhances, or otherwise facilitates resistance of the wheat plants to leaf rust and / or stripe rust disease.

The invention discloses a quick molecular detection method of a novel mycelium T4 injecting wheat stripe rust with AABBDDXX. The method comprises the following steps: screening to obtain two specific RAPD (Random Amplified Polymorphic DNA) marks S1311 and S1363 of T4 by use of 189 RAPD random primers among the novel mycelium T4, epidemic strains of wheat stripe rust CYR29, CYR31, CYR32, CYR33 and Su11-4 and a novel mycelium V26 injecting an anti-stripe rust gene Yr26; recovering, purifying, cloning and sequencing the specific stripes, designing an SCAR (Sequence Characterized Amplified Regions) primer according to the sequencing result, and successfully converting the RAPD marks to stable SCAR marks T4SP8-1 / T4SP8-2 (the sequence is 5'GGGCGTGGATGAAGAG-3' / 5'-GGAGCAGAAGCAGGTTT3'); stably amplifying the specific stripe of the novel mycelium T4 at 700bp by the marks. The specific SCAR marks T4SP8-1 / T4SP8-2 of the novel mycelium T4 provided by the invention can be used for realizing quick molecular detection of the novel mycelium T4 in an early stage in a large field so as to understand the variation dynamic condition of the pathogenic bacteria, thereby providing a reliable technical support and a theoretical foundation for prophylaxis and treatment policy of the mycelium and the wheat stripe rust.

The invention relates to a detection and identification kit of a composite PCR of wheat stripe rust fungus and leaf rust fungus, which belongs to the technical fields of biotechnology, crop disease control and plant quarantine. The kit detects the specific genome DNA sequences of the wheat stripe rust fungus 171 bp and the leaf rust fungus 226 bp simultaneously in a primary PCR reaction by three primers from a fungal beta-tubulin gene conserved sequence and wheat stripe rust fungus and leaf rust fungus specific sequences. The invention provides supplement and improvement on the wheat stripe rust fungus and leaf rust fungus specific primer detecting method, and is suitable for the diagnostic detection of the stripe rust fungus and the leaf rust fungus in an infected wheat leaf before disease symptoms appear. Composite PCR technology is adopted in the kit, and in a PCR-SMART reaction solution, the three primers are amplified simultaneously, so the detection accuracy is increased, the detection time is saved, the operation is simple, and the kit can be applied and popularized at plant protection and plant quarantine departments in China.

The present invention discloses a method for breeding multigene polymerized wheat germplasm capable of resisting powdery mildew, stripe rust and verticillium wilt. Said method includes the following steps: utilizing STS marker of Pm4 to detect that the wheat to be detected has the gene Pm4a for resisting powdery mildew or not; utilizing SCAR marker of Pm13 to detect that the wheat to be detected has the gene Pm13 capable of resisting powdery mildew or not; utilizing SCAR marker of Pm21 to detect that the wheat to be detected has the gene PmV capable of resisting powdery mildew or not; utilizing SCAR marker of Bdv2 to detect that the wheat to be detected has the gene Bdv2 for resisting verticillium wilt or not; and utilizing SSR marker of YrX to detect that the wheat to be detected has the gene YrX for resisting stripe rust or not. Said invention provides a new method for breeding new wheat variety capable of resisting powdery mildew, stripe rust and verticillium wilt.

The invention relates to a pesticide composition containing prothioconazole and triazoles, which comprises active ingredient A and active ingredient B, wherein active ingredient A is selected from prothioconazole, and active ingredient B is selected from cyproconazole , flusilazole, triconazole, wherein the weight ratio of active ingredient A to active ingredient B is 80:1 to 1:80, made into wettable powder, water dispersible granule, suspending agent, suspoemulsion, Water emulsion, microemulsion, used to control powdery mildew, sheath blight, fusarium wilt, leaf spot, rust, sclerotinia, net spot, sclerotinia, gray mold, black spot, brown spot, rust , scab, white rot, leaf rust, stripe rust, glume blight, leaf mold and other diseases, it has the characteristics of small dosage, resistance to rain erosion, and obvious synergy.