Indoor Toxicity of Emamectin Benzoate and Chlorantraniliprole Against Spodoptera litura and Their Residues on Lotus Plants

Spodoptera litura is the most threatening pest in lotus production,seriously affecting the lotus yield and quality.Emamectin benzoate and chlorantraniliprole,the main insecticides for controlling S.litura on vegetables,are widely used by farmers to control S.litura on lotus plants.To determine the application concentrations,control effects,and safety of the two insecticides in lotus fields,indoor experiments were conducted to determine the control effects of 200 g/L chlorantraniliprole(SC)and 5%emamectin benzoate(WDG),and the residues of the two insecticides in the water,lotus leaves,and lotus seeds after field application were determined by HPLC-MS/MS.The indoor experiment results showed that chlorantraniliprole and emamectin benzoate both had good control effects on S.litura,with the median lethal concentrations(LC50)of 17.700 and 1.694 mg/L,respectively.After unmanned aerial vehicle spraying of emamectin benzoate at 20 g/667m^(2),there was no residue of emamectin benzoate in the water or lotus leaves after 5 d.After spraying of chlorantraniliprole at 20 mL/667m^(2),the residual amounts in the water and lotus leaves after 9 d were 0.005 and 0.007 mg/L,respectively.No residue of the two insecticides was detected in lotus seeds(dry and fresh)2 h after spraying.Therefore,it was recommended that chlorantraniliprole and emamectin benzoate can be used to control S.litura in lotus fields during the growth period,while attention should be paid to the application interval for safety.Considering the safe harvesting of lotus seeds and leaves,it was recommended that the preharvest intervals of chlorantraniliprole and 5%emamectin benzoate should be 9 d.

Biochemical Mechanism of Chlorantraniliprole Resistance in the Diamondback Moth, Plutella xylostella Linnaeus

The insecticide chlorantraniliprole exhibits good efifcacy and plays an important role in controlling the diamondback moth, Plutella xylostella Linnaeus. However, resistance to chlorantraniliprole has been observed recently in some ifeld populations. At present study, diamondback moths with resistance to chlorantraniliprole （resistant ratio （RR） was 82.18） for biochemical assays were selected. The assays were performed to determine potential resistance mechanisms. The results showed that the selected resistant moths （GDLZ-R） and susceptible moth could be synergized by known metabolic inhibitors such as piperonyl butoxide （PBO）, triphenyl phosphate （TPP） and diethyl-maleate （DEM） at different levels （1.68-5.50-fold and 2.20-2.89-fold, respectively）, and DEM showed the maximum synergism in both strains. In enzymes assays, a high level of glutathione-S-transferase （GST） was observed in the resistant moth, in contrast, moths that are susceptible to the insecticide had only 1/3 the GST activity of the resistant moths. The analysis of short-term exposure of chlorantraniliprole on biochemical response in the resistant strain also showed that GST activity was signiifcantly elevated after exposure to a sub-lethal concentration of chlorantraniliprole （about 1/3 LC50, 12 mg L-1） 12 and 24 h, respectively. The results show that there is a strong correlation between the enzyme activity and resistance, and GST is likely the main detoxiifcation mechanism responsible for resistance to chlorantraniliprole in P. xylostella L., cytochrome P450 monooxygenase （P450） and carboxy-lesterase （CarE） are involved in to some extent.

The Sublethal Effects of Chlorantraniliprole on Helicoverpa armigera (Lepidoptera: Noctuidae)

Sublethal effects of chlorantraniliprole to Helicoverpa armigera （Hiibner） larvae were evaluated through exposure of third instar larvae to the insecticide incorporated into an artificial diet. When larvae were fed on the insecticide-containing diet for 7 d, the LC10, LC20, LC40, and LC50values were 3.790, 7.977, 21.577, and 33.121 μg active ingredient L^-1, respectively. Chlorantraniliprole at sublethal concentrations significantly reduced the larval body mass, emergence ratio, adult longevity and egg hatching rate in both the parental and offspring generations. The pupation and copulation rate in the parental generation and the pupal mass in the offspring also strongly decreased. Reproduction was seriously disturbed in both the parental and offspring groups even when only one of the partners was exposed to chlorantraniliprole at larval stages. However, at the lowest concentration of exposure （LC^0）, offspring fecundity was strongly reduced only when both partners were exposed. The net reproductive rate （R0）, intrinsic rate of increase （rm）, and gross reproduction rate （GRR） at LC20, LC40 concentrations were significantly lower than that of the control. Post-exposure effects also included an extended larval developmental time and increased male proportion in both generations. The doubling time （Dt） at LC20, LC40 concentrations as well as gross reproduction rate （GRR） at LC10 concentration were also significantly increased. Chlorantraniliprole might have significant effects on H. armigera population dynamics even at sublethal concentrations on both parental and offspring generations.

Evaluation of Lethal Effects of Chlorantraniliprole on Chilo suppressalis and Its Larval Parasitoid, Cotesia chilonis

Chlorantraniliprole was introduced into China from 2008 as a novel insecticide to control the rice stem borer, Chilo suppressalis （Walker）. Cotesia chilonis （Matsumura） is the major parasitoid of C. suppressalis. We collected seven populations of C. suppressalis and two populations of C. chilonis in different locations in China in 2009 to investigate the lethal effects of chlorantraniliprole on them. The populations of C. suppressalis from different regions showed various LD50 values ranging from 2.00 to 18.70 ng per larva. Chlorantraniliprole has negligible acute contact toxicity （LC50500 mg L-1） to C. chilonis and its oral toxicity is also much lower than that of fipronil （2 800-fold difference in LC50）. The results indicated that chlorantraniliprole is a good alterative in rice integrated pest management （IPM） programs. The susceptibility data of C. suppressalis will be useful for monitoring resistance levels in future.

Synthesis and Insecticidal Activities of Novel Analogues of Chlorantraniliprole Containing Nitro Group

Twelve novel analogues of chlorantraniliprole containing nitro group were synthesized,and their structures were characterized by 1H NMR and high-resolution mass spectrometry（HRMS）.Their evaluated insecticidal activities against oriental armyworm（Mythimna separata） indicate that the nitro-containing analogues showed favorable insecticidal activities,while the activity of compounds 5g at 0.25mg/L was 40%,but still lower than chlorantraniliprole.

Development and validation of an analytical method for detecting chlorantraniliprole residues in fresh tea leaves

An efficient method using multiwalled carbon nanotubes(MWCNTs)as dispersive solid-phase extraction sorbent was established for determining chlorantraniliprole residues in fresh tea leaves,which are known to be a troublesome matrix containing abundant pigments,via gas chromatography with an electron capture detector.Acetonitrile was used as the extraction solvent,with sodium chloride enhancing the analyte partition in the organic phase.The optimal mixture of MWCNTs and primary secondary amine(PSA)was based on the distribution of the target analyte recovery and on the clean-up efficiency;while matrix-matched calibration was recommended to combat the matrix effect.Mean recoveries of 95.2%–108.8%were obtained with intraday and interday precisions of less than 7.9%and 10.3%,respectively.Good linearity was observed for concentrations of 0.02–1.0 mg/kg with a correlation coefficient of 0.9984.The limits of detection and quantification were 0.005 mg/kg and 0.02 mg/kg,respectively.The method was employed to investigate the dissipation dynamics of chlorantraniliprole in fresh tea leaves with real field samples.Consequently,the dissipation rates of chlorantraniliprole in fresh tea leaves followed pseudo-first-order kinetics with a half-life of 1.9 d,and the average chlorantraniliprole residue content was below 0.02 mg/kg with a harvest withholding period of 14 d.

杀虫剂chlorantraniliprole合成新方法

改进杀虫剂chlorantraniliprole合成方法,以3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-羧酸、2-氨基-5-氯-3-甲基苯甲酸为原料,使用光气/3-甲基吡啶体系催化进行合环反应,最后与一甲胺反应生成目标化合物chlorantraniliprole,其结构经过1H NMR确证。在最佳的光气用量、合环反应温度条件下的总收率为81.4%,高效液相纯度为96.4%。改进后的合成方法反应条件温和,反应时间短,后处理简单,三废较少;原料廉价易得,经济可行性高。

Molecular characterization of the ryanodine receptor from Adoxophyes orana and its response to lethal and sublethal doses of chlorantraniliprole

The insect ryanodine receptor(RyR)is a novel target of the anthranilic and phthalic insecticides,which have high activity against lepidopteran insects.Several diamide insecticides have been used to control pests in orchards in China.To enhance our understanding of the effects of diamides on RyRs,full-length cDNAs were isolated and characterized from the summer fruit tortrix moth,Adoxophyes orana,which is the most severe pest of stone and pome trees worldwide.In addition,the modulation of AoRyRmRNA expression by diamide insecticides was investigated.The AoRyRmRNA obtained had an open reading frame(ORF)of 15402 bp nucleotides encoding 5113 amino acids,and shared high and low identity with its orthologs in other insects and mammals of 77–92 and 45–47%identity,respectively.One alternative splice site with two exclusive exons was revealed in AoRyR(a/b).The usage of exon was more frequent in eggs and larvae than in pupae and adults.Quantitative real-time reverse transcription PCR(qRT-PCR)showed that AoRyRmRNA was expressed at all developmental stages,especially in eggs,male pupae and male adults.The expression levels of AoRyRmRNA in the whole body were up-regulated markedly after 3 rd instar larvae were treated with chlorantraniliprole at LC_(10),LC_(20)and LC_(50)dosages.The results could provide the basis for further functional studies of Ao Ry R and for the development of new chemicals with selective activity against insects.

The Effect and Benefit of Rice Chilo suppressalis Walker Chemical Control Test of Chlorantraniliprole etc.

In this paper, the first generation and second generation of Chilo suppressalis Walker were conducted as the test objects to investigate control of a new pesticide(chlorantraniliprole) with preparation of chlorantraniliprole 20% SC,abamectin 1.8% EC and chlorpyrifos 40% EC to Chilo suppressalis Walker. The results showed that chlorantraniliprole 20% SC, abamectin 1.8% EC and chlorpyrifos40% EC had effective control to Chilo suppressalis Walker for its excellent control efficacy and long persistence period. Seedling protection efficacies were between84.2%-100%, 90.1% and 92.1%, and insecticidal efficacies were between 84.6%-100%,90.7% and 93.8% 36 days after application of chlorantraniliprole 20% SC in treatments with abamectin 1.8% EC and chlorpyrifos 40% EC for first generation Chilo suppressalis Walker control. The dead panicles were between 0.2%-1.4%, 0.8%and 0.7%, pest plant rate control in 0.4%-2.2%, 1.1% and 0.9%, and the rates of damaged rice plants were between 82.4%-97.6%, 90.2%-91.2% and 91.4%-92.8%,30 days after application of chlorantraniliprole 20% SC, abamectin 1.8% EC and chlorpyrifos 40% EC for the second generation Chilo suppressalis Walker control. It can effectively protect seedlings, protect spike, increase grain number and grain weight, which promoting the increase production income effect. The real estate increased by 9.7%-12.3%, 10.9% and 11.2% than water treatment(CK) with a very significant level, while the incomes were higher than 1 719.19-1 998.22, 1 956.52 and 2 057.83 yuan.

Evaluation of the toxic effect of insecticide chlorantraniliprole on the silkworm Bombyx mori(Lepidoptera:Bombycidae)

The silkworm Bombyx mori feeds exclusively on mulberry leaves and is highly sensitive to pesticides in general. Although mulberry plantations are free of agrochemicals, pesticide drift can occur. Chlorantraniliprole, a novel insecticide of the anthranilic diamides class, has been used to control pests in field crops. In this study, we investigated the biological effects of different concentrations of chlorantraniliprole on B. mori silkworm commercial Brazilian hybrids. To evaluate the toxicity of chlorantraniliprole, bioassays were carried out and data on the lethal concentrations, symptomatology, morphology and variables of silk production were collected. Results indicated that B. mori is extremely sensitive to chlorantraniliprole, even in low concentrations. The highest silkworm mortality rates were observed in the two highest chlorantraniliprole concentrations, 0.2 and 0.1 ppm. Although lower chlorantraniliprole concentrations did not cause death of all the silkworm larvae, various symptoms of toxicity were observed: feeding cessation, regurgitation, late development and incomplete ecdysis. Such symptoms reflect the morphological changes we observed in the midgut epithelium, which affected nutrient uptake and metabolism, and even the production of cocoons. Exposed larvae also produced?thin-shelled cocoons, which constitutes a serious economic problem because this type of cocoon is not useful for the silk industry. The results provided herein confirm the toxicity of chlorantraniliprole in silkworm larvae. Therefore, we strongly suggest that, competent authorities of the National Health Surveillance Agency, in pesticide management should take measures to reduce or eliminate the use of chlorantraniliprole in areas nearest to silkworm cultivation.

Control Effect of 35% Thiamethoxam-prochloraz FS to Plant Diseases and Insect Pests at Rice Seedling Stage and Safety Evaluation

The prevention and control effect of 35% thiamethoxam-prochloraz FS to rice thrips and rice bakanae disease and its influence on the quality of rice seedlings were studied. The results show that when 100 kg of rice seeds were coated with 200 g of 35% thiamethoxam-prochloraz FS,the control effects to rice thrips were 93.0% and 84.7% 15 and 20 days after sowing, and the control effect to rice bakanae disease was 90.8% 30 days after sowing. As 100 kg of rice seeds were coated with 250 g of 35% thiamethoxam-prochloraz FS, the control effects to rice thrips were 98.2% and 94.9% 15 and 20 days after sowing, and the control ef- fect to rice bakanae disease was 94.6% 30 days after sowing. 35% thiamethoxam- prochloraz FS is safe to rice seedlings and can effectively promote the growth of rice seedlings.

25%阿克泰(Thiamethoxam)可分散性粒剂防治烟粉虱试验初报

采用25％阿克泰（Thiamethoxam）可分散性粒剂4000～8000倍液进行移栽后喷雾和采用阿克泰WG2000～4000倍液进行移栽前苗期灌根处理，对番茄烟粉虱的防治效果均明显好于对照药剂，表明阿克泰WG对烟粉虱具有较高活性。试验结果表明，阿克泰WG对烟粉虱的若虫也具有较好的杀伤效果。施用阿克泰WG对番茄植株安全。

Effects of imidacloprid and thiamethoxam as seed treatments on the early seedling characteristics and aphid-resistance of oilseed rape

Seed treatments with the neonicotinoid insecticides imidacloprid and thiamethoxam were evaluated to determine whether the chemicals at effective concentrations for aphid control would influence the germination and early growth of oilseed rape,Brassica napus.Treatment with imidacloprid or thiamethoxam did not affect the cumulative germination rate,but significantly inhibited establishment potential by suppressing root system development in the cotyledon stage.However,these alterations in seedling development in the thiamethoxam-treated seeds appeared not to be detrimental as leaves developed;in contrast,for the seedlings with imidacloprid as seed treatment agent,a significantly decreased shoot/root ratio was still evident at the late two-leaf stage.After two leaves developed,chlorophyll content per leaf in the thiamethoxam treatment was significantly higher than that of the control,while chlorophyll content per leaf in the imidacloprid treatment remained close to that in the control.Most other parameters,i.e.,height,leaf area,weight of stem,leaf or root,and other growth indexes,between the treatments and the control showed no significant difference.Additionally,it was found that storage time of the treated seeds had a significant effect on cumulative germination rate.Treatment 30 d before planting significantly reduced germination relative to that of the control.All of the plants treated with neonicotinoids were shown to have significant anti-aphid characteristics that persisted until the end of the trial.

Control Effect Evaluation of 70% Thiamethoxam ZF against Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus on Sugarcane

[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [ Result ] 70% Thiamethoxam ZF had good con-rol effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm^2 （effective ingredients 315 g）. 70% Thiamethoxam ZF （ dosage per hm^2 ） mixed with the regular fertilizer （ dosage per hm^2 ） should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm^2 and 6.8% respectively compared to blank control. [ Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustained- release, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area.

Field Efficacy Trials of 1%Bifenthrin·thiamethoxam GR against Sweet Potato Weevil

[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A total of 4 field trials were conducted in Guangdong Province,including 1%bifenthrin·thiamethoxam GR applied at the doses of 3,4 and 5 kg/667 m^(2),and 3%phoxim GR applied at the dose of 4 kg/667 m^(2).[Results]1%Bifenthrin·thiamethoxam GR applied at the dose of 5 kg/667 m^(2)had excellent control effects on sweet potato weevil,with an average control effect of 77.60%,which was significantly higher than that of 3%phoxim GR applied at the dose of 4 kg/667 m^(2)(48.52%).And the average yield increase rate of sweet potato treated with 1%bifenthrin·thiamethoxam GR reached 24.79%,significantly higher than 12.37%in the control group.[Conclusions]1%Bifenthrin·thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5-7 d after planting,and the recommended dosage is 5 kg/667 m^(2),which will have good control effect on sweet potato weevil and increase the yield of sweet potato.

氯虫苯甲酰胺与杀虫单复配处理水稻种子对稻纵卷叶螟的防效及持效机理

稻纵卷叶螟Cnaphalocrocis medinalis是水稻生产上重要的迁飞性害虫,为开发出适用于种子处理且可长效防控稻纵卷叶螟的复配药剂,通过室内内吸活性测定、田间防效验证及植株中药剂含量检测,研究了氯虫苯甲酰胺和杀虫单复配的最适比例及对稻纵卷叶螟的田间防治效果,初步明确了复配剂的持效机理。内吸活性测定结果表明,氯虫苯甲酰胺和杀虫单质量浓度比为2:3时,共毒系数最高,内吸能力最强。按照该配比制备的25%氯虫·杀虫单种子处理悬浮剂(FS,分别含10%氯虫苯甲酰胺和15%杀虫单)在7.5~15 g/kg (种子,以下同)剂量范围内进行拌种处理,对水稻发芽和出苗安全。田间试验表明,采用25%氯虫·杀虫单FS按7.5~15 g/kg剂量拌种处理,对田间稻纵卷叶螟具有较好的控制作用,且持效期长,播种后94 d仍有70%左右的保叶效果。植株中药剂含量检测结果表明,25%氯虫·杀虫单FS对稻纵卷叶螟的持效控害能力主要与叶片中氯虫苯甲酰胺的残留含量有关,复配剂中的杀虫单虽然降解较快,但其在苗期可提高水稻根部对氯虫苯甲酰胺的吸收率。本研究结果可为开发防治稻纵卷叶螟的种子处理药剂提供理论依据及技术参考。

The study of pesticide-fertilizer combination prepared with biochar and chlorantraniliprole and its effectiveness in controlling fall armyworms

In this research,a pesticide-fertilizer combination(PFC)was fabricated using chlorantraniliprole and biochar.The PFC had a spherical shape,smooth surface,uniform particles,relatively dense structure and good compression resistance.The adsorption propertie of biochar to chlorantraniliprole was investigated.During the preparation of pelleted granules,the types and concentrations of corefillers and adhesives were screened and optimized.Besides,the safety to maize and effectiveness against fall armyworms of PFC had been investigated.Meanwhile,The PFC could promoted growth of maize significantly and control fall armyworm effectively.This work provides a promising approach to slow the release of chlorantraniliprole,which has a potential application to enhance the pesticides efficiency.

Quantification of Thiamethoxam in Rhizomes and Leaves of the Hedychium coronarium and Water and Soil by High-Pressure Liquid Chromatography

The linearity, stability, accuracy and inter-day precisions of the assay method were evaluated in water, soil and rhizomes and leaves of Hedychium coronarium of the Zingiberaceae family. Mato Grosso do Sul is a predominantly agricultural state in Brazil and has many rivers and permanent and seasonal lakes, in which the Hedychium coronarium, an aquatic plant, is found the swampy environments. The prepared samples were analyzed quantitatively by High Performance Liquid Chromatography with PDA and UV detection for the presence of thiamethoxam. The thiamethoxam was recovered from these samples at rates ranging from 81.16% - 99.93%. The coefficient of variation in the quantitative analysis of the thiamethoxam was under 5%. The linearity of the method was determined by linear regression. The analysis of the samples spiked with known amounts of analyte demonstrated that the response was proportional to the concentrations of the samples with determination coefficients of r2 = 0.9992 (water and soil) and r2 = 0.9990 (leaves and rhizomes) for the linear range of the analytical calibration curves of the samples. The detection limit was 0.36 μg.L-1 and quantification limit was 1.2 μg.L-1 for thiamethoxam. The method was considered sensitive for quantification of the thiamethoxam in water, soil and rhizomes and leaves of Hedychium coronarium.

红螯螯虾幼虾对4种水稻农药耐受性研究

为了解稻田常用的生物农药或杀虫剂对红螯螯虾大规格幼虾的毒性效应,测定了中生菌素、氯虫·噻虫嗪、噻唑锌和井冈霉素A对其的急性毒性反应。结果表明:4种农药对红螯螯虾大规格幼虾96 h半致死浓度分别为19.66、1.65、1132.83、2092.07 mg/L。安全浓度分别为5.65、1.27、260.40、248.11 mg/L,根据耐受性和行为特征观察发现,4种药物对于4 cm左右的红螯螯虾幼虾的毒性大小依次为氯虫·噻虫嗪>中生菌素>噻唑锌>井冈霉素A,根据国家标准(GB/T16310.5—1996),噻唑锌和井冈霉素A对于4 cm红螯螯虾幼苗属于无毒农药,中生菌素属于微毒农药,而氯虫·噻虫嗪为中毒农药。本试验明确了红螯螯虾幼虾对水稻常用农药的耐受性,为红螯螯虾-水稻综合种养过程中的病害防治工作提供参考。

70%噻虫嗪种子处理可分散粉剂拌种对大麦蚜虫的防治效果及增产作用

为了探索防治大麦蚜虫的科学有效措施,选用保山市大面积推广的二棱品种“保啤麦28号”,每10 kg种子分别用20、30、40 g 70%噻虫嗪种子处理可分散粉剂拌种防治蚜虫。结果表明:不同用量的70%噻虫嗪种子处理可分散粉剂拌种能有效抑制蚜虫对大麦的危害。大麦拔节期前,防效均达100%;大麦孕穗期至抽穗扬花期,防效为72.30%~95.70%;大麦灌浆期,防效为33.60%~80.04%;大麦乳熟期,防效为14.20%~49.44%,防效随着用量的增加而增加,且持效期更长;每10 kg种子用药30、40 g防效最佳,与每10 kg种子用30 mL的30%噻虫嗪悬浮种衣剂拌种防效相近。药剂拌种对大麦还具有增产作用,增产率为8.6%~16.9%。建议在大麦生产中,根据当地蚜虫发生规律选择不同用量、不同剂型的杀虫剂拌种防治大麦蚜虫,综合考虑防效、成本和用量,达到节本、增效的目的。