This study compared the control effect of 110 g/L etoxazole SC,15%abamectin·etoxazole SC,30%cyetpyrafen SC,43%bifenazate SC and 1.8%abamectin EC five acaricides sprayed by unmanned aerial vehicle(UAV)on Panonychu...This study compared the control effect of 110 g/L etoxazole SC,15%abamectin·etoxazole SC,30%cyetpyrafen SC,43%bifenazate SC and 1.8%abamectin EC five acaricides sprayed by unmanned aerial vehicle(UAV)on Panonychus citri,aiming to screen out the appropriate acaricide for the control of this pest by UAV spraying.The results showed that 15%abamectin·etoxazole SC and 30%cyetpyrafen SC had the highest control efficacy,which remained above 90%14 d after application.Secondary performance was observed in 43%bifenazate SC and 110 g/L etoxazole SC,which demonstrated enhancing control effect.However,1.8%abamectin EC showed slower effect.Considering the control effect and population reduction rate of P.citri,15%abamectin·etoxazole SC and 30%cyetpyrafen SC were suggested as the effective acaricides for the control of this pest.展开更多
[Objective] This study aimed to compare the effects of sublimed sulfur and acaricide on controlling bee mites.[Method] Three independent experiments were carried out in the same apiary during 2007-2009.[Results] The r...[Objective] This study aimed to compare the effects of sublimed sulfur and acaricide on controlling bee mites.[Method] Three independent experiments were carried out in the same apiary during 2007-2009.[Results] The results showed that this method is effective in eliminating mites settled on combs or hidden during pupae phase,but not in controlling the mites parasitized on adult bees.The control effect on killing Varroa destructor after treated appeared optimal in the first day and then decreased,and that on killing Tvopilaelaps clareae happened in the second day.The results indicated that the effect would be much better if the bees can be treated 1 time to 2 times again in the following 2-5 days after the first treatment.Back to data pool,we found that the treatment of sublimed sulfur paired with acaricide is effective in controlling V.destructor and T.clareae.[Conclusion] This technique could facilitate the apicultural production in the regions suffered from V.destructor and T.clareae.展开更多
The effects of retarding resistance evolution of mixing and sequencing acaricides were studied based on the resistance selection of three acaricides to Tetranychus cinnabarinus in the laboratory. Tetrany-chus cinnabar...The effects of retarding resistance evolution of mixing and sequencing acaricides were studied based on the resistance selection of three acaricides to Tetranychus cinnabarinus in the laboratory. Tetrany-chus cinnabarinus was continuously selected with fenpropathrin, abamectin and pyridaban for 28, 30 and 31 generations, respectively, and resistance factor increased to 65.6, 7.2 and 1.2 time, accordingly. Results of cross-resistance determination suggested that there were no cross-resistance existed among the three acaricides. Analysis of resistance selection and estimation of realized heritability (h2) of resistance to three single and two mixed acaricides showed that a mixture of fenpropathrin+abamectin would slow resistance development compared with a sequence of fenpropathrin followed by abamectin while the mixture of pyridaben+abamectin and the sequence of pyridaben followed by abamectin would effectively retard resistance evolution.展开更多
A series of new compounds as highly potential acaricides was synthesized based on the structure of spiro-diclofen. Their structures were identified by 1H NMR spectroscopy and element analysis. The bioassay indicated t...A series of new compounds as highly potential acaricides was synthesized based on the structure of spiro-diclofen. Their structures were identified by 1H NMR spectroscopy and element analysis. The bioassay indicated that most of the compounds exhibited excellent acaricidal activities, what’s more, the bioactivities of some new compounds were better than that of the commercial spirodiclofen at a concentration of 20 μg/mL. The relationship between structure and biological activity was also discussed.展开更多
Threshold trait analysis was used to estimate realized heritability (h 2) of re sistance to five acaricides (three single acaricide and two mixtures) and resistance risk in Tetranychus cinnabarinus (Boiduval). Tetran...Threshold trait analysis was used to estimate realized heritability (h 2) of re sistance to five acaricides (three single acaricide and two mixtures) and resistance risk in Tetranychus cinnabarinus (Boiduval). Tetranychus cinnabarinus collected from the field of Beibei, Chongqing reared more than 60 generations under pesticide free conditions and considered s usceptible. Successively selected for about 30 generations, the strain had a 65.55-, 5.82 - , 1.23-, 5.20- and 1.42-fold increase in resistance to fenpropathrin, abam ectin, pyridaben, pyridab en-abamectin (pyridaben: abamectin=7.4:0.1, m/m) and fenpropathrin-abamectin (fenpropathri n: abamectin=8.9:0.1, m/m), respectively. The realized heritability of resista nce t o fenpropathrin, abamectin, pyridaben, pyridaben-abamectin (pyridaben: abamectin=7.4:0.1, m/m) and fenpropathrin-abamectin (fenpropathrin: abamectin=8.9:0.1, m/m) is 0.2167, 0 .0967, 0.0130, 0.0800 and 0.0172, respectively. Under the selected condition, a 10-fold incr ease in resistance would be expected 15 generations for fenpropathrin, 34 generations for abamectin , 333 generations for pyridaben, 42 generations for pyridaben-abamectin (pyridaben: a bamectin=7.4:0.1, m/m) and 200 generations for fenpropathrin-abametcin (fenpropathrin: abamectin= 8.9:0.1, m/m). The highest resistance risk of the five acaricides in Tetranychus cinnabarinus was fenpropathrin, then abamection, pyridaben-abamectin (pyridaben: abamectin=7.4:0.1, m/m), fen propathrin- abamectin (fenpropathrin: abamectin=8.9:0.1, m/m) and that to py ridaben was the lowest. The mixture of pyridaben and abamectin is not useful in delaying development of resistance in the pest to the two single acaricide while the mixture of fenpropathrin and abamectin could do it.展开更多
The carmine spider mite, Tetranychus cinnabarinus （Boisduval） and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests ha...The carmine spider mite, Tetranychus cinnabarinus （Boisduval） and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year-round inten- sive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respec- tive highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region.展开更多
The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different tim...The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LCso values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.展开更多
Fourteen avermectin B2 a aglycon derivatives were designed and synthesized after removing the oleandrose disaccharide of avermectin B2 a.Their structures were characterized by’H NMR,13 C NMR,HMRS.Preliminary bioassay...Fourteen avermectin B2 a aglycon derivatives were designed and synthesized after removing the oleandrose disaccharide of avermectin B2 a.Their structures were characterized by’H NMR,13 C NMR,HMRS.Preliminary bioassays indicated that these compounds exhibited good insecticidal activity against diamondback moth at 200 mg/L,with mortality no less than 90%.Compounds 10 b,12 a,12 c,17 demonstrated good acaricidal activity against the adult mites,larvae,and good inhibition rate of hatching to mite eggs of Tetranychus cinnabarinus.Compounds 5,10 b,10 c exhibited excellent fungicidal activity against fourteen fungal pathogens in vitro.3 D-QSAR analysis showed that the fungicidal activity of avermectin B2 a aglycon derivatives would be increased when a negatively charged and bulky group was introduced at 13-position,which will be instructive for the further modification of avermectin B2 aaglycon.展开更多
Sensitive spectrophotometric method for determination of kelthane in sub parts per million level is described, which is based on Fujiwara reaction. Kelthane on alkaline hydrolysis gives chloroform, which can be reacte...Sensitive spectrophotometric method for determination of kelthane in sub parts per million level is described, which is based on Fujiwara reaction. Kelthane on alkaline hydrolysis gives chloroform, which can be reacted with pyridine to produce red colour. The colour is discharged by addition of glacial acetic acid. Then Benzidine (4,4’-Bianiline) reagent is added due to which a yellowish-red colour is formed which has an absorption maximum at 490nm. Beer’s law is obeyed in the range of 3.3 - 26.0 μg (0.13 - 1.04 ppm) of Kelthane per 25ml of final solution. The molar absorptivity and Sandell’s sensitivity were found to be 4.32 × 105 L?mol–1?cm–1 and 0.022 μg?cm–2 respectively. The method is found to be free from interferences of other organochlorine pesticides and various co-pollutants and can be successfully applied for the determination of kelthane in environmental samples.展开更多
A series of new pyrazole oximes bearing substituted thiazole ring were designed and prepared. The structures of the title compounds were identified by spectral analyses, The results of primary bioassay indicated that ...A series of new pyrazole oximes bearing substituted thiazole ring were designed and prepared. The structures of the title compounds were identified by spectral analyses, The results of primary bioassay indicated that some targeted compounds exhibited promising insecticidal activity besides acaricidal activity, particularly; compounds 8c and 8d were more potent against Tetranychus cinnabarinus and Plutella xylostella than other analogues.展开更多
Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.f...Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.farinae)and Dermalophagoides pteronyssinus(D.pteronyssinus).Methods:Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations(50.00%,25.00%,12.50%,6.25%and 3.13%)and exposure times(24hrs,48hrs,72hrs and 96 hrs).All treatments were replicated 7 times,and the experiment repeated once.The topical and contact activities of the two herbs were investigated.Results:Mortalities from lemongrass extract were higher than neem for both topical and contact activities.At 50%concentration,both 24 hrs topical and contact exposures to lemongrass resulted in more than 91%mortalities for both species of inites.At the same concentration and exposure time,neem resulted in topical mortalities of 40.3%and 15.7%against D.pteronyssinus and D.farinae respectively;contact mortalities were 8.0%and 8.9%against the 2 mites,respectively.There was no difference in topical mortalities of D.pteronyssinus from exposure to concentrations oflemongrass and neem up to 12.50%;lemongrass was more effective than neem at the higher concentrations.Conclusions:Generally,topical mortalities of D.farinae due to lemongrass are higher than that due to neem.Contact mortalities of lemongrass are always higher that neem against both species of mites.展开更多
Objective: To evaluate the acaricidal activity of the essential oil obtained from roots of Derris floribunda(D. floribunda)(Miq.) Benth, and its main constituent nerolidol against the Mexican mite Tetranychus mexicanu...Objective: To evaluate the acaricidal activity of the essential oil obtained from roots of Derris floribunda(D. floribunda)(Miq.) Benth, and its main constituent nerolidol against the Mexican mite Tetranychus mexicanus(T. mexicanus)(Mc Gregor).Methods: The essential oil from the roots of D. floribunda collected in the Amazon region(Brazil) was obtained by hydrodistillation. Its chemical composition was determined by GC–MS analysis. The acaricidal activities of this essential oil and nerolidol,were evaluated by recording the number of dead females(mortality) and eggs(fertility).Results: The essential oil showed sesquiterpenes as major volatile components. Nerolidol, the main component, represented 68.5% of the total composition of the essential oil. D. floribunda essential oil and nerolidol showed acaricidal activity, with LC_(50) of9.61 mg/m L air and 9.2 mg/m L air, respectively, over a 72 h period. In addition, both the essential oil and nerolidol significantly reduced the fecundity of T. mexicanus.Conclusions: Due to the economic importance of T. mexicanus and the lack of new pesticides, our data are very promising in the search for efficient and safer acaricidal products. Furthermore, this is the first report about the chemical composition and bioactivity of the essential oil of the Amazon plant species D. floribunda.展开更多
Acaricidal activity of Boenninghausenia sessilicarpa against Panonychus cirri was tested in the laboratory. Four solvents were used to prepare crude extracts, petroleum ether, chloroform, ethyl acetate, and ethanol, a...Acaricidal activity of Boenninghausenia sessilicarpa against Panonychus cirri was tested in the laboratory. Four solvents were used to prepare crude extracts, petroleum ether, chloroform, ethyl acetate, and ethanol, among which ethanol was the most effective one. The results suggested that ethanol extracts of B. sessilicarpa had eminent acaricidal and ovicidal activities. Concentrated extracts were prepared using petroleum ether, chloroform, ethyl acetate, or distilled water as solvent. Mite mortality rates in the concentrated extracts by petroleum ether, chloroform, or distilled water were significantly lower than those by ethyl acetate. The LC50 values of eggs and female mites were 0.7639 and 1.1033 mg mL^-1, respectively. After liquid chromatography and thin layer chromatography, the concentrated extracts were separated into 14 groups of fractions and further tests for their acaricidal and ovicidal activities were conducted. Fraction 2 was found to possess higher acaricidal and ovicidal activities. The mortality of eggs and adult mites were 85.83 and 63.07%, respectively. Moreover, fraction 2 showed moderate oviposition inhibition effect （0.8795） against P. citri when the used dose was higher than 2.5 mg mL^-1展开更多
A series of novel pyrazole oxime derivatives containing oxazole ring were designed and synthesized. The title compounds were structurally confirmed by 1H NMR, 13C NMR spectra and elemental analyses. Preliminary bioass...A series of novel pyrazole oxime derivatives containing oxazole ring were designed and synthesized. The title compounds were structurally confirmed by 1H NMR, 13C NMR spectra and elemental analyses. Preliminary bioassay results showed that some of the title compounds displayed promising fungicidal activity besides insecticidal and acaricidal activity. Particularly, compound 8c exhibited potent fungicidal activity against cucumber Pseudoperonospora cubensis beyond good insecticidal activity against Aphis craccivora and Nilaparvata lugens.展开更多
Pyriminostrobin, a new acaricide, was discovered in our previous studies. Because introducing fluorine into organic compounds can increase bioactivity, pyriminostrobin was modified as a series of strobilurin-pyrimidin...Pyriminostrobin, a new acaricide, was discovered in our previous studies. Because introducing fluorine into organic compounds can increase bioactivity, pyriminostrobin was modified as a series of strobilurin-pyrimidine derivatives for biological screening. The compounds were characterized by 1H NMR, MS and elemental analysis. Preliminary bioassays demonstrated that compounds 7e and 7i exhibited significant control against Tetranychus cinnabarinus （Boisd.） at 0.625 mg L^-1, and their acaricidal potencies were higher than pyriminostrobin in a greenhouse. The relationship between structure and acaricidal activity was also studied.展开更多
Sixteen new derivatives of spiromesifen were synthesized from 3-（2,4,6-trimethylphenyl）-4-hydroxy-△^3-dihydrofuran-2-one. Their bioactivities against diamondbackmoth （Plutella xylostella） and spider mites （Tetra...Sixteen new derivatives of spiromesifen were synthesized from 3-（2,4,6-trimethylphenyl）-4-hydroxy-△^3-dihydrofuran-2-one. Their bioactivities against diamondbackmoth （Plutella xylostella） and spider mites （Tetranychus cinnabarinus） were also evaluated. The structures of these derivatives were confirmed by ^1H NMR, MS.展开更多
A novel synthesis of 2,3-dihydroimidazo[1,2-a]pyridin-5 (1H)-one 4 and its derivatives were described.Preliminary bioassays showed that some of the target compounds exhibited excellent insecticidal activities against ...A novel synthesis of 2,3-dihydroimidazo[1,2-a]pyridin-5 (1H)-one 4 and its derivatives were described.Preliminary bioassays showed that some of the target compounds exhibited excellent insecticidal activities against brown planthopper (Nilaparvata lugens), cowpea aphids (Aphis craccivora) (4,5 a, 5 c, 5 g,5 h, 5 j, 5 r, 6 b, 6 e) and carmine spider mite (Tetranychus cinnabarinus (5 f, 5 s, 6 a) at 500 mg/L. Among them,compound 4 was still active against brown planthopper and cowpea aphids at 4 mg/L. The insecticidal activities were influenced by the types and position of the substituents, which provided guidance for the structure modifications.展开更多
Six new 13-O-acylavermectin Bl aglycones(3-8) were synthesized from avermectin B1 aglycone and their bioactivities were evaluated against Spodoptera exigua, Spodoptera eridania, Tetranychus urticae and Aphis fabae.
Groundwater in Egypt plays an important role in the country＇s water budget. South Western desert represent an arid of desert biome within world＇s net-work of the biosphere reserves. In this study, the plant wild veg...Groundwater in Egypt plays an important role in the country＇s water budget. South Western desert represent an arid of desert biome within world＇s net-work of the biosphere reserves. In this study, the plant wild vegetation were surveyed in Abu Tartur mining area located in the Southern part of Western depending essentially on the seepage from water line tubes which supplies water demands at Abu Tartur. The vegetation-environment relationships in Abu Tartur are described. Data sets （42 species in 38 plots） beside the pip-line enriched from 13 wells were analyzed, using multivariate procedures, i.e., two-way indicator species analysis （TW1NSPAN）, detrended correspondence analysis （DCA） and detrended canonical correspondence analysis （CCA）, to produce a classification of plant communities in the studied areas and to examine the relationships of that plant communities to certain edaphic factors. Five plant communities were identified. Astragalus vogelii, Chenopodium murale, Citrullus colocynthis, Fagonia arabica, Farsetia aegyptia, Hyoscyamus muticus, Morettia philaeana, Cynodon dactylon, Trichodesma africana, Tarnarix nilotica, Senna italica, Schouwia purpurea, Salsola volkensii and Phragmites australis were common in the study area. Phytochemical survey for nitroprpionic compounds in some taxa belonging to Fabaceae family showed the absence of these toxic compounds by using GC/MS analysis. Also some phytochemical components ofAstragalus vogalii were extracted and identified by GC/MS spectra. A biological activity, in this regard was the screening of methanol extracts for some wild taxa of Abu Tartur against natural Tetranychus urticae as acricidal activity and the methanol extracts of some taxa give high mortality results, like Farsetia aegyptia （86.6%） and Fagonia arabica Burm. f. （70.0%）.展开更多
This study reports the extraction of <i>Jatropha curcas</i> leaves using supercritical CO<sub>2</sub>. Experiments were performed varying the pressure (13 and 20 MPa) and the temperature (50...This study reports the extraction of <i>Jatropha curcas</i> leaves using supercritical CO<sub>2</sub>. Experiments were performed varying the pressure (13 and 20 MPa) and the temperature (50°C and 60°C). The model of Sovová for supercritical fluid extraction was fitted to the experimental kinetic extraction curves. Two cell sizes were used and scale up equations compared. GC analysis showed phytol, carvacrol, and hexahydrofarnesyl acetone as major compounds in all the experiments. A maximum yield of 0.95% dry-weight basis was obtained. It was observed a maximum yield (0.95% dry-weight basis) extract obtained at 20 MPa and 50°C. The results indicated that the mass yield increased with the increase of pressure. The bioassays showed that the extract of <i>J. curcas</i> possessed toxicity against <i>Hyalomma lusitanicum</i>.展开更多
文摘This study compared the control effect of 110 g/L etoxazole SC,15%abamectin·etoxazole SC,30%cyetpyrafen SC,43%bifenazate SC and 1.8%abamectin EC five acaricides sprayed by unmanned aerial vehicle(UAV)on Panonychus citri,aiming to screen out the appropriate acaricide for the control of this pest by UAV spraying.The results showed that 15%abamectin·etoxazole SC and 30%cyetpyrafen SC had the highest control efficacy,which remained above 90%14 d after application.Secondary performance was observed in 43%bifenazate SC and 110 g/L etoxazole SC,which demonstrated enhancing control effect.However,1.8%abamectin EC showed slower effect.Considering the control effect and population reduction rate of P.citri,15%abamectin·etoxazole SC and 30%cyetpyrafen SC were suggested as the effective acaricides for the control of this pest.
基金Supported by Special Fund for the Construction of Modern Agricultural Technology System(NYCYTX-43-syz3)~~
文摘[Objective] This study aimed to compare the effects of sublimed sulfur and acaricide on controlling bee mites.[Method] Three independent experiments were carried out in the same apiary during 2007-2009.[Results] The results showed that this method is effective in eliminating mites settled on combs or hidden during pupae phase,but not in controlling the mites parasitized on adult bees.The control effect on killing Varroa destructor after treated appeared optimal in the first day and then decreased,and that on killing Tvopilaelaps clareae happened in the second day.The results indicated that the effect would be much better if the bees can be treated 1 time to 2 times again in the following 2-5 days after the first treatment.Back to data pool,we found that the treatment of sublimed sulfur paired with acaricide is effective in controlling V.destructor and T.clareae.[Conclusion] This technique could facilitate the apicultural production in the regions suffered from V.destructor and T.clareae.
文摘The effects of retarding resistance evolution of mixing and sequencing acaricides were studied based on the resistance selection of three acaricides to Tetranychus cinnabarinus in the laboratory. Tetrany-chus cinnabarinus was continuously selected with fenpropathrin, abamectin and pyridaban for 28, 30 and 31 generations, respectively, and resistance factor increased to 65.6, 7.2 and 1.2 time, accordingly. Results of cross-resistance determination suggested that there were no cross-resistance existed among the three acaricides. Analysis of resistance selection and estimation of realized heritability (h2) of resistance to three single and two mixed acaricides showed that a mixture of fenpropathrin+abamectin would slow resistance development compared with a sequence of fenpropathrin followed by abamectin while the mixture of pyridaben+abamectin and the sequence of pyridaben followed by abamectin would effectively retard resistance evolution.
文摘A series of new compounds as highly potential acaricides was synthesized based on the structure of spiro-diclofen. Their structures were identified by 1H NMR spectroscopy and element analysis. The bioassay indicated that most of the compounds exhibited excellent acaricidal activities, what’s more, the bioactivities of some new compounds were better than that of the commercial spirodiclofen at a concentration of 20 μg/mL. The relationship between structure and biological activity was also discussed.
文摘Threshold trait analysis was used to estimate realized heritability (h 2) of re sistance to five acaricides (three single acaricide and two mixtures) and resistance risk in Tetranychus cinnabarinus (Boiduval). Tetranychus cinnabarinus collected from the field of Beibei, Chongqing reared more than 60 generations under pesticide free conditions and considered s usceptible. Successively selected for about 30 generations, the strain had a 65.55-, 5.82 - , 1.23-, 5.20- and 1.42-fold increase in resistance to fenpropathrin, abam ectin, pyridaben, pyridab en-abamectin (pyridaben: abamectin=7.4:0.1, m/m) and fenpropathrin-abamectin (fenpropathri n: abamectin=8.9:0.1, m/m), respectively. The realized heritability of resista nce t o fenpropathrin, abamectin, pyridaben, pyridaben-abamectin (pyridaben: abamectin=7.4:0.1, m/m) and fenpropathrin-abamectin (fenpropathrin: abamectin=8.9:0.1, m/m) is 0.2167, 0 .0967, 0.0130, 0.0800 and 0.0172, respectively. Under the selected condition, a 10-fold incr ease in resistance would be expected 15 generations for fenpropathrin, 34 generations for abamectin , 333 generations for pyridaben, 42 generations for pyridaben-abamectin (pyridaben: a bamectin=7.4:0.1, m/m) and 200 generations for fenpropathrin-abametcin (fenpropathrin: abamectin= 8.9:0.1, m/m). The highest resistance risk of the five acaricides in Tetranychus cinnabarinus was fenpropathrin, then abamection, pyridaben-abamectin (pyridaben: abamectin=7.4:0.1, m/m), fen propathrin- abamectin (fenpropathrin: abamectin=8.9:0.1, m/m) and that to py ridaben was the lowest. The mixture of pyridaben and abamectin is not useful in delaying development of resistance in the pest to the two single acaricide while the mixture of fenpropathrin and abamectin could do it.
文摘The carmine spider mite, Tetranychus cinnabarinus （Boisduval） and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year-round inten- sive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respec- tive highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region.
文摘The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LCso values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.
基金supported by the National Key R&D Program of China (No.2018YFD0200100)
文摘Fourteen avermectin B2 a aglycon derivatives were designed and synthesized after removing the oleandrose disaccharide of avermectin B2 a.Their structures were characterized by’H NMR,13 C NMR,HMRS.Preliminary bioassays indicated that these compounds exhibited good insecticidal activity against diamondback moth at 200 mg/L,with mortality no less than 90%.Compounds 10 b,12 a,12 c,17 demonstrated good acaricidal activity against the adult mites,larvae,and good inhibition rate of hatching to mite eggs of Tetranychus cinnabarinus.Compounds 5,10 b,10 c exhibited excellent fungicidal activity against fourteen fungal pathogens in vitro.3 D-QSAR analysis showed that the fungicidal activity of avermectin B2 a aglycon derivatives would be increased when a negatively charged and bulky group was introduced at 13-position,which will be instructive for the further modification of avermectin B2 aaglycon.
文摘Sensitive spectrophotometric method for determination of kelthane in sub parts per million level is described, which is based on Fujiwara reaction. Kelthane on alkaline hydrolysis gives chloroform, which can be reacted with pyridine to produce red colour. The colour is discharged by addition of glacial acetic acid. Then Benzidine (4,4’-Bianiline) reagent is added due to which a yellowish-red colour is formed which has an absorption maximum at 490nm. Beer’s law is obeyed in the range of 3.3 - 26.0 μg (0.13 - 1.04 ppm) of Kelthane per 25ml of final solution. The molar absorptivity and Sandell’s sensitivity were found to be 4.32 × 105 L?mol–1?cm–1 and 0.022 μg?cm–2 respectively. The method is found to be free from interferences of other organochlorine pesticides and various co-pollutants and can be successfully applied for the determination of kelthane in environmental samples.
基金financial supported by the National Natural Science Foundation of China(No.21202089)China Postdoctoral Science Foundation(No.2013M531145)the Research Foundation of the Six People Peak of Jiangsu Province(No.2013-SWYY-013)
文摘A series of new pyrazole oximes bearing substituted thiazole ring were designed and prepared. The structures of the title compounds were identified by spectral analyses, The results of primary bioassay indicated that some targeted compounds exhibited promising insecticidal activity besides acaricidal activity, particularly; compounds 8c and 8d were more potent against Tetranychus cinnabarinus and Plutella xylostella than other analogues.
文摘Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.farinae)and Dermalophagoides pteronyssinus(D.pteronyssinus).Methods:Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations(50.00%,25.00%,12.50%,6.25%and 3.13%)and exposure times(24hrs,48hrs,72hrs and 96 hrs).All treatments were replicated 7 times,and the experiment repeated once.The topical and contact activities of the two herbs were investigated.Results:Mortalities from lemongrass extract were higher than neem for both topical and contact activities.At 50%concentration,both 24 hrs topical and contact exposures to lemongrass resulted in more than 91%mortalities for both species of inites.At the same concentration and exposure time,neem resulted in topical mortalities of 40.3%and 15.7%against D.pteronyssinus and D.farinae respectively;contact mortalities were 8.0%and 8.9%against the 2 mites,respectively.There was no difference in topical mortalities of D.pteronyssinus from exposure to concentrations oflemongrass and neem up to 12.50%;lemongrass was more effective than neem at the higher concentrations.Conclusions:Generally,topical mortalities of D.farinae due to lemongrass are higher than that due to neem.Contact mortalities of lemongrass are always higher that neem against both species of mites.
基金financially supported by Fundacao de Amparo a Pesquisa do Estado do Amazonas (FAPEAM – PAPAC program EDITAL N. 015/2014)
文摘Objective: To evaluate the acaricidal activity of the essential oil obtained from roots of Derris floribunda(D. floribunda)(Miq.) Benth, and its main constituent nerolidol against the Mexican mite Tetranychus mexicanus(T. mexicanus)(Mc Gregor).Methods: The essential oil from the roots of D. floribunda collected in the Amazon region(Brazil) was obtained by hydrodistillation. Its chemical composition was determined by GC–MS analysis. The acaricidal activities of this essential oil and nerolidol,were evaluated by recording the number of dead females(mortality) and eggs(fertility).Results: The essential oil showed sesquiterpenes as major volatile components. Nerolidol, the main component, represented 68.5% of the total composition of the essential oil. D. floribunda essential oil and nerolidol showed acaricidal activity, with LC_(50) of9.61 mg/m L air and 9.2 mg/m L air, respectively, over a 72 h period. In addition, both the essential oil and nerolidol significantly reduced the fecundity of T. mexicanus.Conclusions: Due to the economic importance of T. mexicanus and the lack of new pesticides, our data are very promising in the search for efficient and safer acaricidal products. Furthermore, this is the first report about the chemical composition and bioactivity of the essential oil of the Amazon plant species D. floribunda.
基金supported by the Special Public Sector Research of China (nyhyzx07-057)the National Key Technology R&D Program of China(2007BAD47B04, 2008BAD92B08)
文摘Acaricidal activity of Boenninghausenia sessilicarpa against Panonychus cirri was tested in the laboratory. Four solvents were used to prepare crude extracts, petroleum ether, chloroform, ethyl acetate, and ethanol, among which ethanol was the most effective one. The results suggested that ethanol extracts of B. sessilicarpa had eminent acaricidal and ovicidal activities. Concentrated extracts were prepared using petroleum ether, chloroform, ethyl acetate, or distilled water as solvent. Mite mortality rates in the concentrated extracts by petroleum ether, chloroform, or distilled water were significantly lower than those by ethyl acetate. The LC50 values of eggs and female mites were 0.7639 and 1.1033 mg mL^-1, respectively. After liquid chromatography and thin layer chromatography, the concentrated extracts were separated into 14 groups of fractions and further tests for their acaricidal and ovicidal activities were conducted. Fraction 2 was found to possess higher acaricidal and ovicidal activities. The mortality of eggs and adult mites were 85.83 and 63.07%, respectively. Moreover, fraction 2 showed moderate oviposition inhibition effect （0.8795） against P. citri when the used dose was higher than 2.5 mg mL^-1
基金funded by the National Natural Science Foundation of China (No.21202089)the Research Foundation of the Six People Peak of Jiangsu Province (Nos.2011-SWYY-009,2013-SWYY-013)the Technology Project Fund of Nantong City (Nos.AS2013004,CP12013002)
文摘A series of novel pyrazole oxime derivatives containing oxazole ring were designed and synthesized. The title compounds were structurally confirmed by 1H NMR, 13C NMR spectra and elemental analyses. Preliminary bioassay results showed that some of the title compounds displayed promising fungicidal activity besides insecticidal and acaricidal activity. Particularly, compound 8c exhibited potent fungicidal activity against cucumber Pseudoperonospora cubensis beyond good insecticidal activity against Aphis craccivora and Nilaparvata lugens.
基金the Outstanding Young Scholarship from the National Natural Science Foundation of China(No.30825043)NSFC(No.21172202)+2 种基金the Outstanding Scholar Foundation of Henan Province(No.094100510019)for financial supportsupported by the National Key Basic Research Program of China(973 Program)(Nos.2010CB126105 and 2012CB724501)the National Key Technology Support Program during the 12th Five-Year Plan Period(Nos.2011BAE06B00,2011BAE06B01,2011BAE06B02,2011BAE06B03 and 2011BAE06B05)
文摘Pyriminostrobin, a new acaricide, was discovered in our previous studies. Because introducing fluorine into organic compounds can increase bioactivity, pyriminostrobin was modified as a series of strobilurin-pyrimidine derivatives for biological screening. The compounds were characterized by 1H NMR, MS and elemental analysis. Preliminary bioassays demonstrated that compounds 7e and 7i exhibited significant control against Tetranychus cinnabarinus （Boisd.） at 0.625 mg L^-1, and their acaricidal potencies were higher than pyriminostrobin in a greenhouse. The relationship between structure and acaricidal activity was also studied.
基金supported by National Natural Science Foundation of China(No.30700532)the Science and Technology Project of Zhejiang province(Nos.2008C02007-3 and 2008C21029)
文摘Sixteen new derivatives of spiromesifen were synthesized from 3-（2,4,6-trimethylphenyl）-4-hydroxy-△^3-dihydrofuran-2-one. Their bioactivities against diamondbackmoth （Plutella xylostella） and spider mites （Tetranychus cinnabarinus） were also evaluated. The structures of these derivatives were confirmed by ^1H NMR, MS.
基金financial supported by the National Key Research Program of China(No. 2017YFD0200500)National Natural Science Foundation of China(No.21672061)supported by the Fundamental Research Funds for the Central Universities(No. 222201718004)
文摘A novel synthesis of 2,3-dihydroimidazo[1,2-a]pyridin-5 (1H)-one 4 and its derivatives were described.Preliminary bioassays showed that some of the target compounds exhibited excellent insecticidal activities against brown planthopper (Nilaparvata lugens), cowpea aphids (Aphis craccivora) (4,5 a, 5 c, 5 g,5 h, 5 j, 5 r, 6 b, 6 e) and carmine spider mite (Tetranychus cinnabarinus (5 f, 5 s, 6 a) at 500 mg/L. Among them,compound 4 was still active against brown planthopper and cowpea aphids at 4 mg/L. The insecticidal activities were influenced by the types and position of the substituents, which provided guidance for the structure modifications.
文摘Six new 13-O-acylavermectin Bl aglycones(3-8) were synthesized from avermectin B1 aglycone and their bioactivities were evaluated against Spodoptera exigua, Spodoptera eridania, Tetranychus urticae and Aphis fabae.
文摘Groundwater in Egypt plays an important role in the country＇s water budget. South Western desert represent an arid of desert biome within world＇s net-work of the biosphere reserves. In this study, the plant wild vegetation were surveyed in Abu Tartur mining area located in the Southern part of Western depending essentially on the seepage from water line tubes which supplies water demands at Abu Tartur. The vegetation-environment relationships in Abu Tartur are described. Data sets （42 species in 38 plots） beside the pip-line enriched from 13 wells were analyzed, using multivariate procedures, i.e., two-way indicator species analysis （TW1NSPAN）, detrended correspondence analysis （DCA） and detrended canonical correspondence analysis （CCA）, to produce a classification of plant communities in the studied areas and to examine the relationships of that plant communities to certain edaphic factors. Five plant communities were identified. Astragalus vogelii, Chenopodium murale, Citrullus colocynthis, Fagonia arabica, Farsetia aegyptia, Hyoscyamus muticus, Morettia philaeana, Cynodon dactylon, Trichodesma africana, Tarnarix nilotica, Senna italica, Schouwia purpurea, Salsola volkensii and Phragmites australis were common in the study area. Phytochemical survey for nitroprpionic compounds in some taxa belonging to Fabaceae family showed the absence of these toxic compounds by using GC/MS analysis. Also some phytochemical components ofAstragalus vogalii were extracted and identified by GC/MS spectra. A biological activity, in this regard was the screening of methanol extracts for some wild taxa of Abu Tartur against natural Tetranychus urticae as acricidal activity and the methanol extracts of some taxa give high mortality results, like Farsetia aegyptia （86.6%） and Fagonia arabica Burm. f. （70.0%）.
文摘This study reports the extraction of <i>Jatropha curcas</i> leaves using supercritical CO<sub>2</sub>. Experiments were performed varying the pressure (13 and 20 MPa) and the temperature (50°C and 60°C). The model of Sovová for supercritical fluid extraction was fitted to the experimental kinetic extraction curves. Two cell sizes were used and scale up equations compared. GC analysis showed phytol, carvacrol, and hexahydrofarnesyl acetone as major compounds in all the experiments. A maximum yield of 0.95% dry-weight basis was obtained. It was observed a maximum yield (0.95% dry-weight basis) extract obtained at 20 MPa and 50°C. The results indicated that the mass yield increased with the increase of pressure. The bioassays showed that the extract of <i>J. curcas</i> possessed toxicity against <i>Hyalomma lusitanicum</i>.
