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The Toxicity of Several Kinds of Insecticides and the Preparation of Micro-emulsion to Stomphastis Thraustica Meyrick

Stomphastis thraustica Meyrick is one of the most important pests of Jatropha curcas L. The larva of leaf miner live in and eat the mesophyll, the infested areas by the larva form insect spots which show the growth record of the larva on the leaves. As the larva grows, the spots become wider and left their excrements in the insect spots, which would affects the transportation of water and nutrition, then retard the growth of the trees.Stomphastis thraustica Meyrick have rapid reproduction and occurred many generations annually in field, the generations were seriously overlapped, which caused difficulties in pest control activities. The purposes of this study were to select some insecticides with different mechanisms which were effective to control Stomphastis thraustica Meyrick, and raw insecticides can be formulated to micro-emulsion(ME). Comparing with other formulations, the advantages of ME as follow:ultra-fine-grain emulsion, strong permeability, adopting water in place of a plurality of organic solvents which fit the need of water solution pesticide agent producing. Utilizing these advantages, ME avoid shortcomings of traditional dosage form and enhance its efficiency. The major procedures and results of this experiment are as below:1.Insecticides screening:In this experiment, five kinds of insecticides with different mechanisms(triazophos, cypermethrin, monosultap, diflubenzuron and emamectin benzoate) are screened. The susceptibility of the egg, early larvae and 2nd-instar larvae of Stomphastis thraustica Meyrick to different insecticides was conducted with the immersion method and leaf dipping method. The results showed that emamectin benzoate exhibited highest efficacy against 2nd-instar larvae of Stomphastis thraustica Meyrick with LC5o=1.67mg/L after 48h. Triazophos exhibited lower efficacy than emamectin benzoate, but it exhibited strongly inhibitory to eggs, resulting in a 48.98% hatching rate. In view of this, emamectin benzoate and triazophos were chose to screen compound proportion. Several ratios were evaluated by applying the co-toxicity coefficient method and mathematical model. The result of screening is that the proportion of emamectin benzoate and triazophos is 1:26.4, and this co-toxicity coefficient(CTC) reached the highest which was 278.58, showing a synergistic effect and this ratio was used in mixture product development.2.The preparation of ME:based on structure theories of ME, after solvent, emulsifiers as well as their ratio screening and product quality test, the optimal prescription of 13.7% Emamectin benzoate and Triazophos ME was reported as follows:emamectin benzoate(0.5%), triazophos(13.2%), solvent(5~8%), the proportion of the mixture of surfactant,500:600:E-1310=1:2:3,which totally occupied 24% weight of the formulation, n-butanol(12%), the other component is water.3. The quality inspection of ME:the general indicators including heat-storage stability, cold-storage stability, emulsion stability, pH value and so on were examined referring to related domestic standard. The test results conformed to the standard4. The field experiments of ME:the experiment results indicated that the efficacy of 13.7% Emamectin benzoate and Triazophos ME was much better than that of emulsifiable concentrate. The control efficacy of 13.7% Emamectin benzoate and Triazophos ME diluted 1000,1500 and 2000 times were 96.41%、94.55% and 87.05.% respectively.

Research and Preparation of the Combined Emulsifiable Concentrate of 7.1% Methoxyfenozide and Emamectin Benzoate

With the greater increasing investment risks in synthesize and production of novel pesticides, the longer market period and the more rapid development of pest resistance, the supply of efficient pesticides appear to be in great shorter. The rational combination among different pesticides play an important role in the following aspects: pest resistance control, improving control effect, decreasing the cost, a good harvest, prolonged application longevity of pesticides and lesser environment pollution.Methoxyfenozide belongs to the diacylhydrazine class of insect growth regulators, and it is effective for the control of most Lepidoptera pest, however it is safe for others orders pest such as Coleoptera, Homoptera, and so on. The test results of lab and field suggested: It is highly effective to Lepidoptera, and not harmful to insects of other orders such as bee, which is helpful to integrated pest management.Emamectin benzoate is synthesized from avermectin, which is derived from the antibiotic-producing actinomycetes Streptomyces avermictilis. It possesses many characteristics of biopesticide such as high efficiency, low toxicity, and low residue. At very low dosage, emamectin benzoate has high efficiency to Lepidoptera pest larvae and mites, and it is safe to beneficial insect, which is important to integrated pest management and has been considered as a substitute product for toxic and high residue pesticide.The two pesticides above have prominent advangtages. Meanwhile, methoxyfenozide is still in patent protection stage and there are no related combination products at home and abroad. So there is an excellent potential combination foreground of two pesticides. 7.1% methoxyfenozide~emamectin benzoate EC was selected through the optimum of various components with orthogonal design on the basis of optimal ratio of methoxyfenozide and emamectin benzoate, and these could supply some technical bases for further methoxyfenozide application. The main research methods and results could be summarized as follows:1 Screening of the optimal single pesticide

Processing and Mechanism Research of Emamectin Benzoate Micro-emulsion

Emamectin benzoate which was developed by the United States Merck was an efficient,broad-spectrum,non-pollution biological pesticide.Because of it’s high activity and low preparation,Emamectin benzoate was widely used today.But the main preparation on the current market was emamectin benzoate EC,it need to consume a large amount of organic solvents,such as xylene,which was likely to lead to environmental pollution,waste of resources,and increase costs.In order to reduce environmental pollution,improve the effect of preparation and save costs,In this study,it was produced as an environment-friendly form which achieve good environment and economic benefits.The research could be summaried as followed:1.By the study,the prescription of emamectin benzoate 1%ME was filtrated and appropriate solvent and emulsifier were selected.The best solvent was the mixture of cyclohexanone and N’N-dimethylformamide(1:2,m/m),which was 15%weight of total composition;the emulsifier was a certain ratio of alkylphenols polyoxyethylene ether,styrene polyoxyethylene-phenol ethers and 500#,occupied 15%weight;the content of co-surfactant(n-octanol)was 2%weight,the other conponent was water. The factors that influence cold and hot storage stability were studied.The results showed the qualified indicators of the sample quality and the perfect adaptability of formula.2.The pseudo-ternary phase diagrams of emamectin benzoate microemulsion with four different kinds of emulsifier were plotted based on the electric conductivity.The phase diagram could support the filtration of emamectin benzoate Microemulsion surfactant and improve efficiency.ME with hydrophilic surfactants have wide transparent temperature range in high temperature area,and ME with lipophilic surfactants have wide transparent temperature range in low temperature area and good low-temperature stability.Low-temperature stability of micro-emulsion,emulsion stability and transparent temperature range were greatly influenced by Surfactant structure and the amount.Adding surfactant could improve the performances of salt-dimensional micro-emulsion.3.Study on low-temperature stability,cloud point,emulsion stability,the impact of high temperature stability of pesticide Micro-emulsion it was showed that Choosing a suitable solvent,surfactant can improve the low-temperature stability of micro-emulsion;along with the increasing of the hydrophilic surfactant-(EO),the higher cloud point was.The increasing in higher-hydrophilic surfactant was conducive to raise Micro-emulsion emulsion stability.High surfactant/water(w/w) ratio was propitious to the formation “compactly” the boundary layer which was difficult for the hydrone to penetrate,or even if it could penetrate by “the fetter” form and be existent,but it couldn’t contact with the effective component of pesticide, which could assured hot storage stability.4.Study on the electrical conductivity of salt-dimensional micro-structural changes in the emulsion showed that with the addition of water,the micro-emulsion in the emulsion W/O structure,LCD,bicontinuous structure and O/W structural of salt-dimensional structure changed,which held a preliminary discussion on the mechanism.5.The qualitative and quantitative analysis method of emamectin benzoate micro-emulsion with HPLC was studied.The decomposition rate was less than 5%, which measured up to the national standards.Through determination of the indoor toxicity,the LC50 changed little after.This also showed that the preparation of hot storage stability was better

Study on Compound Biological Insecticides of Spodoptera Litura and Clone and Sequence Analysis of pif-2 Gene in SpltMNPV-JP-B

Spodoptera litura Fabricius is one of the most important pests of vegetables, plants and many crops. It is abound in the world recently and their damage are serious. Because of the large-scale use and irrationality application of chemical pesticides, the level of drug resistance of Spodoptera litura Fabricius increase obviously. It also gave great difficulties to pest control. Abusing chemical causes the environmental pollution, ecosystem destruction; it also hurt the Health of human and animals. So effort to reduce the use of chemical pesticides to promote biological control in the integrated pest management is the need for sustainable Agricultural development.Spodoptera litura multicapsid nucleopolyhedrovirus (SpltMNPV) is a biological pathogen, it can control the host population obviously and has already been commercial production. However, because the virus has high host specificity and do no effect to other insects except target organism. However, it can’t effect on pests control as quickly as possible. It has some shortages in practical application. For expanding the control species of the insects and improving the insecticidal effect, we use SpltMNPV and mix emamectin benzoate with them, then test the toxicity of the mixtures in the lab and in the field. At last, some obvious results are gotten. As the same time clone and sequence analysis of pif-2 gene that has some contact with per os infection of SpltMNPV is done at the level of molecule. Main results are as follows:1. In the laboratory in conditions of different mixtures, concentrations and temperatures, we mixed Chinese SpltMNPV(CN), three strains of Japanese SpltMNPV(A、B、C) with emamectin benzoate and then tested their toxicity to the larvae of Spodoptera litura. The result was that the mix of 106PIB/mL SpltMNPV Japanese strain (B) and 1% emamectin benzoate’s 1000 times dilution has strong and obvious biological activity. Its LT50 was 22.22% and 44.44% shorter than the single emamectin benzoate and nucleopolyhedrov- iruse separately. It had an obvious effect.2. Chose the compound biological insecticides to do experiments for controlling Spodoptera litura Fabricius, Plutelaxylo stelo, Diaphania iadiea in the field. The results showed that the compound biological insecticide had 76.67%~88.48% and 92.92%~ 96.30% revised mortality for Spodoptera litura Fabricius after using 4days and 7days, and a little higher than 71.63%~84.16% and 87.56%~92.77% of single emamectin benzoate and more higher than 21.95%~45.13% and 68.83%~86.11% of single virus. As the same time, the compound insecticide also can control Lepidoptera pests such as Plutelaxylo stelo and Diaphania iadiea and so on. It has greater applied value on production.3. Clone and analyzing nucleotide and amino acid sequence of gene pif-2 in SpltMNPV Japanese strain(B)was done at the molecular biological level. The second-structure of protein PIF-2 was predicted and homology between a series of pif-2 at the level of molecular system was analysed. It had contributed to the improvement and development of this virus insecticide, and further study of baculovirus.

Study on 34.5% Emamectin Benzoate-Chlorfenapyr Water Dispersible Granule

As people care their Health more and more,the pollution-flee production of vegetables was also cared more and more.So it was one of the important guarantee that using the water dispersible granule(WDG) of water-based pesticide new formulations to control the insects of vegetables.This paper aims to screen out the best ingredient percentage of Emamectin benzoate and Chlorfenapyr,and machining them into WDG,in order to control the important vegetable insects of Prodenia litura(Fabricius) effectively. Thus,this paper has been studied from the following aspects.The toxicity in the lab to Prodenia litura(Fabricius) larvae was tested with spot and leaf-dipping.Emamectin benzoate and Chlorfenapyr that had high toxicity to Prodenia litura(Fabricius) 3nd instar larvae were screened out from seven common pesticides. When tested with leaf-dipping 48 hours later,the LC(50) of Emamectin benzoate is 0.1182mg/L,and the LC50 of Chlorfenapyr is 0.8232mg/L.The best ingredient percentage was screened with Horsfall toxicity test design and leaf-dipping.The results showed that when the ingredient percentage of Emamectin benzoate and Chlorfenapyr was 1:16.25,the synergistic effect was the most obvious,and the co-toxicity coefficient was 316.52.Various auxiliary agents were screened with single factor experimentation,and the formulation was optimized with orthogonal trail design,finally the best formulation of 34.5%Emamectin benzoate- Chlorfenapyr WDG was screened out.The formulation was consisted of Emamectin benzoate and Chlorfenapyr as raw material 34.5% (Emamectin benzoate 2%,Chlorfenapyr 32.5%),BX as wetting agent 6%,NNO and Polyoxyethylene dodecyl alcohol ether mixed in the percentage of 1:1 as dispersing agents 6%,Ammonium sulfate as cracking agent 5%,PEG200 as adhesive 1%,China clay and Bentonite mixed in the percentage of 1:2 as carrier complementing to 100%. After the test of the all-around items of the sample,the indexes were as follow:the content of Emamectin benzoate was 2.1%,and the content of Chlorfenapyr was 32.7%,and the wetting time was 41s,and the suspending ratio was 88.2%,and the cracking time was 95s, and the content of water was 1.6%,and the pH was 6.8,and the decomposing ratio in hot store was 1.6%.The toxicity tested in the lab showed that when Prodenia litura(Fabricius) 3nd instar larvae treated with leaf-dipping 48 hours later,the LC50 of this formulation was 0.2813mg/L,and lower than the antitheses pesticides of 10%Chlorfenapyr SC and 4.5% Beta-Cypermethrin EC obviously.The field controlling trail was carried out with the formulation of 34.5%Emamectin benzoate- Chlorfenapyr WDG and the antitheses pesticides of 2.0%Emamectin benzoate ME and 10%Chlorfenapyr SC to Prodenia litura(Fabricius) and Plutella xylostella (Linnaeus).The results showed that when the dosage was 8g/667m2 in the field,the formulation of 34.5%Emamectin benzoate- Chlorfenapyr WDG had well controlling effect to Prodenia litura(Fabricius) and Plutella xylostella(Linnaeus),and the controlling effect was 97.50%and 98.23%respectively 7d later,and no harm appearing.Thus,the commendable dosage of 34.5%Emamectin benzoate- Chlorfenapyr WDG in the field was 8g/667m2.

The Residual Dynamics in Cabbage and Soil and Adsorption Study of Emamectin Benzoate

This dissertation was concerning with studies on the residue analysis of emamectin benzoate in cabbage and soil,and experment the determination and degradation of emamectin benzoate in cabbge and soil.The adsorption of emamectin benzoate by soil was also studied.The study provides theoretical reference for making the rules of MRL and using the pesticide properly.HPLC-Fluorescence was selected as the analysis method to determine the residue of emamectin benzoate.The cabbage sample were extracted with acetone and ethyl acetate mixture solution,oscillating two times,then the organic phase was collected and evaporated just to dryness,then to being derivatizate.The soil sample were extracted with acetone,and soak through the night,then oscillating three times.After the solution collected was evaporated to no acetone,the remaining phase(add sodium chloride solution) was cleaned up with dichloromathane.The dichloromethane collected was evaporated just to dryness,then to being derivatizate.The derivatization reagent was 1-mathylimidazole and trifluoroacetic anhydride.The method was simple.On the level of 0.005mg/kg、0.05 mg/kg、0.2 mg/kg,the average recovery of emamectin benzoate in cabbage were 78.86%、83.83%、93.67%,and in soil were 74.19%、78.73%、83.06%. The recovery of the method was simple and effective.The degradation of emamectin benzoate in cabbage and soil were studied by HPLC method in Anhui and Hebei province.The degradation procedure of emamectin benzoate was correspond to the mathematic pattern,CT= C0e-kt.In the plant of cabbage,the dynamic equation in Anhui was C=0.0112e-0.1094t and half-life was 6.33d,and the dynamic equation in Hebei was C=0.0121e-0.1211t and half-life was 5.72d.In soil,the dynamic equation in Anhui was C=0.2867e-0.0611t and half-life was 11.34d,and the dynamic equation in Hebei was C=0.208e-0.05724t and half-lifewas 12.11d.The adsorption of emamectin benzoate by soil was studied by the equilibrium method.Four different soil types were used in the study.Emamectin benzoate-calcium chloride solutions(20mL) of different density were added to soil(4g) and were shaken on a shaker at 25℃.A HPLC method was carried out to detect the emamectin benzoate amount in water after 12 hours.The result showed that the adsorption of emamectin benzoate was mainly influenced by organic carbon content and pH of soil.As pH and temperature increased,emamectin benzoate was more absorbed.

The Control Effect of Mixture of Osthol and Emamestin Benzoate on Plutella Xylostella L.

The diamondback moth(DBM),Plutella xylostella(L.),is one of the most destruetive insect pests of cruciferous crops.For the purpose of decreasing resisstance and cut down cost,this paper aims to screen out the best ingredient percentage of osthole and emamestin benzoate and machining them into formulation,in order to control the important vegetable insects of Plutella xylostella(L.) effectively and costly. Thus,this paper has been studied from the following aspects.The toxicity in the lab to Plutella xylostella(L.) larvae was tested with spot and leaf-dipping.When osthole and emamestin benzoate that had high toxicity to Plutella xylostella(L.) 3nd instar larvae were tested with spot 48 hours later,the LC50 of osthole is 41.2109mg/L,and the LC50 of emamectin benzoate is 0.4544mg/L.The LC50 of osthole is 0.3107mg/L,and the LC50 of emamectin benzoate is 0.2133mg/L with leaf-dipping after 24 hours.The best ingredient percentage was screened with Horsfall toxicity test design and leaf-dipping.The results showed that when the ingredient percentage of ostholeand emamectin benzoate was 60:1,the synergistic effect was the most obvious,and the co-toxicity coefficient was 136.The field controlling trail was carried out with the formulation of 0.3% osthole-emamectin benzoate EC and the antitheses pesticides of 2.0%emamectin benzoate ME and 0.4%osthole EC to Plutella xylostella(L.).The results showed that when the dosage was 500 times,1000 times,2000times in the field,the formulation of 0.3%osthole-emamectin benzoate EC had well controlling effect to Plutella xylostella(Linnaeus),and the controlling effect was 98.45%,96.80%and 91.62%after 10d.There are no harm appearing with persistent effect.Thus,the commendable dosage of 0.3%osthole-emamectin benzoate EC in the field was 2000 times.

Preparation of Emamectin Benzoate Emulsion in Water and Its Forming Mechanism of Physical Stable System

EW (Emulsion, Oil in Water) of Agrochemical’s formulation, which is also called as CE(concentrated emulsion), is a new pesticide formulation by using water as dispersing medium,and by the action of dispersant, or emulsifier or other additive agent to make the technical agrochemicals (solid or oil-liquid) suspended or dispersed in water.Applying of high-cutting for emulsion in the prescription filtration of emamectin benzoate 1% EW, the effect of different substances on the EW systematic stability were investigated from the macroscopical angle. The substances included emulsifier、co-emulsifier and thicker. The trial finally confirmed the excellent prescription of triazophos 1% EW. The main conclusion obtained were listed as follows. Emamectin benzoate :1%; xylene and toluene content of 9%; zds-3 1%;EL-20 4.2%; ZDS-1 1.8%; twelve Triacontanol 1%; ZDS-2 0.05%; Glycol 1%.This paper studies the relationship between the different factors and system stability water emulsion ,and explore the internal mechanism of the stability .Come to the conclusion: the choice of emulsifier is the key to the development of water-emulsion; emulsifier and co-emulsifying agent can reduce the interfacial tension, so that forming protective film between oil-water layer; thicker can increase the viscosity to prevent coalescence between the latex particle and enhance emulsion stability; At the research and development of EW, enough energy input is necessary; Median diameter in water research and development, is a very good reference target, The speed of filtration would be accelerated when the application of Median diameter.In the end of the paper, the analysis method of HPLC for the content of emamectin benzoate in the formulation was developed ,which could offer technical reference for the quality control in the industry production..

Effect of Bioactivities and Crop Safety of Emamectin Benzoate Substituted Plant Oil for Xylene

New requirements of green pesticide are proposed for better pesticide solvents recently. Plant oils, which are recycle resources that environmentally friendly, high biodegradation rate, compatible to target, are the first choice to replace organic solvents. Using three kinds of plant oils, including refining pine oil with palm, refining pine oil, and palm oil, we studied the effect of bioactivities and crop safety of 1% emamectin benzoate substituted different plant oils for xylene, such as bioactivities and enzymatic activities of Plutella xylostella L., and physiology and biochemistry of Brassica campestris L. The concrete results are as follows:Allied toxicity measurement showed that two kinds of plant oil solvents combinations increased the insecticidal activity of emamectin benzoate EC significantly. The toxicity index were 0.709 and 0.566 respectively, had synergism. However, as a solvent, palm oil decreased the insecticidal activity of emamectin benzoate EC, its toxicity index was 4.848, decreasing the effect of pesticide.The respiration rate of Plutella xylostella L. showed that the emamectin benzoate EC dissolved in plant oils inhibited the respiration rate, furthermore, the quantity of CO2 that treated with high concentration emamectin benzoate EC which dissolved in plant oils was less than that dissolved in xylene.After treatment with emamectin benzoate EC substituded plant oils for xylene, the activities of digestive enzymes of Plutella xylostella L. showed that the AMS increased, while the pepsin and LPS decreased. The activities of protective enzymes showed that the POD specific activity was lower than that dissolved in xylene, the SOD and CAT specific activities decreased at LC20 but increased at LC50. The activities of detoxifying enzymes showed that the GSTs specific activity increased at LC20 but decreased at LC50. And the AChE specific activity was inhibited significantly.Emamectin benzoate EC dissolved in xylene and palm oil leaded to phytotoxicity to brassica campestris L.but the others not. The new leaves that applied emamectin benzoate EC dissolved in xylene were malformed and not recovered. Another dissolved in palm oil caused the young leaves withering and wilting, but the symptoms disappeared with the leaves growth.After applied with emamectin benzoate EC dissolved in plant oils, nutrients of Brassica campestris L. showed that the protein content decreased, and the amino acid had a small increase, but no effect to chlorophyll. The height of Brassica campestris L. showed that there are no effects to its growth.The research results showed that two kinds of plant oil solvents combinations increased the insecticidal activity of 1% emamectin benzoate EC significantly,and safety to Brassica campestris L. They had great potential on the production.

Studies on Micro-emulsion of Emamection-benzoate and Spreading Analysis on Cabbage and Rice Leaves

Taking the original drug of emamectin-benzoate (hereinafter short for emamectin-benzoate) as research object, 0.5% emamectin-benzoate ME was researched by a systematic formulation experiment in this paper, actions of drops of emamectin-benzoate ME with different surface tension on cabbage and rice leaf were analyzed, and the insecticidal effects against (Plutella xylostella (L.), Chilo supperssalis (Walker) and Cnaphalocrocis medinalis Guenee) were definite. The main results were showed as followed.1. 29 kinds of different formulations of 0.5% emamectin-benzoate ME were prepared with inverse phase method, the kinds and dosages of cosolvents, surfactants, cosurfactants, excipients and antioxidants which were suitable for preparing the ME were screened out successfully after (54±2)℃thermal storage and (0±2)℃cold storage, the optimum formulation was determined. The specification of 0.5% emamectin-benzoate ME is as following: emamectin-benzoate: 0.5% (mass fraction, same as follows.); cosolvent: 6%; mixed-surfactants: 10%; cosurfactants: 2% n-pentanol; excipients: 2.5% PVA1788; antioxidants: 1% TBHQ; antifreeze: 2% ethylene glycol; tap water: add to 100%.2. Contents of emamectin-benzoate in 0.5% emamectin-benzoate ME were measured by HPLC which taking acetonitrile+water as mobile phase. According to FAO standard, the storage stability test of 0.5% emamectin-benzoate ME was carried on at 0℃, then it was shook lightly after 7 days, there were no obvious separation granule and oily things; fast heat storage was also carried on at (54±2)℃, the relative decomposition rate was 1.94% and all other index were eligible after 14 days.3. Surface tension and spreading characteristics of emamectin-benzoate ME drops on cabbage and rice leaf were studied at concentration of 0.78~12.50mg/L. Results showed that the surface tension of emamectin-benzoate ME at 1.56mg/L、3.12mg/L、 6.25mg/L and 12.50mg/L were smaller than the critical surface tension of cabbage and rice leaf; The contact angles of the drops of these solution were different when the drops were dropped onto cabbage and rice leaf, as time went on, the contact angle became smaller, and the higher the concentration was, the faster the contact angle became small,finally, the drops of that the surfactant reached the CMC (critical micelle concentration) in these solution at 3.12mg/L, 6.25mg/L and 12.50mg/L spread completely, while the drops of that the surfactant did not reach the CMC in these solution at 1.56mg/L could not spread completely. The surface tension of emamectin-benzoate ME were smaller than critical surface tension of cabbage and rice leaf at 1.56~100mg/L while the surface tension of emamectin-benzoate EC were greater than critical surface tension of cabbage and rice leaf, and the dynamic retention of the former on cabbage and rice leaf was obviously more than the latter’s at the same concentration.4. Toxicity of 0.5% emamectin-benzoate ME was measured to Plutella xylostella (L.), Spodoptera exigua (Hübner), Prodenia litura (Fabricius) and Helicoverpa armigera (Hübner) by using FAO and domestic standard determination methods, results showed the toxicity of 0.5% emamectin-benzoate ME was slightly higher than that of 1% emamectin-benzoate EC. Pot efficacy tests of 0.5% emamectin-benzoate ME to control Plutella xylostella (L.) and Chilo supperssalis (Walker) showed that the seedling protecting effect of 0.5% emamectin-benzoate ME were better than 1% emamectin-benzoate EC’s at the same concentration with a significant difference; the insecticidal effect of controlling Plutella xylostella (L.) reached 97.88% at 5.0mg/L of emamectin-benzoate ME at 10d after treatment, the seedling protecting effect reached 86.47% at 12.0mg/L of emamectin-benzoate ME at 15d after treatment, which were all higher than other treatments’efficacy.5. According to guidelines for field efficacy trials of pesticides made by Ministry of Agriculture, P.R. China, the field efficacy trials of 0.5% emamectin-benzoate ME to control Cnaphalocrocis medinalis Guenee were completed, results showed that the insecticidal effect and seedling protecting effect of 0.5% emamectin-benzoate ME were better than 1% emamectin-benzoate EC’s at the same concentration; the insecticidal effect and seedling protecting effect of 0.5% emamectin-benzoate ME with mist sprayer were better than 0.5% emamectin-benzoate ME and 1% emamectin-benzoate EC both with manual spray at the same concentration with a significant difference; the seedling protecting effect reached 92.12%, the insecticidal effect reached 92.67% after 10d’s treatment, while the manual spray did not reach such these effects.