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1.
Tissues of higher plants contain novel natural substances that can be used to develop environmental safe methods for insect control. In this study, ethanol extract from flowers of Verbascum cheiranthifolium Boiss. (Scrophulariaceae) was examined for their effect on mortality and progeny production against adults of Rhyzopertha dominica (F.) on two commodities, wheat and barley. The botanical extract was applied at five dose rates, which 0.25, 0.5, 1.0, 2.0 and 3% (w/v). Adults of R. dominica were exposed to the treated wheat and peeled barley at 25 degrees C and 65% RH and mortality was assessed after 24 h, 48 h, 7 day, 14 day and 21 day of exposure. Then all adults were removed and the treated substrate remained at the same conditions for an additional 45 day after this interval, the commodities were checked for progeny production. In two commodities mortality increased with the increase of dose and exposure interval. Results indicated that on wheat, mortality was 100% after 14 days of exposure at the highest dose rate. Whereas, in the same conditions mortality of adults on barley was 63%. Thus plant extract was more effective against adults of R. dominica on wheat than application of barley. Interestingly in two diets, complete suppression (100%) of the progeny production was observed in the treated wheat and barley than in control even in the lowest dose rate.  相似文献   

2.
The insecticidal efficacy of the diatomaceous earth formulation SilicoSec® (Agrinova GmbH, Germany) against the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) was evaluated on peeled rice, paddy rice, maize and barley in laboratory tests. SilicoSec was applied at five dose rates: 0.125, 0.25, 0.5, 1 and 1.5 g/kg of grain. The treated grains were infested with S. oryzae adults, and the weevil mortality was estimated after 24, 48 h, 7 and 14 d of exposure on treated grain. After the 14 d counts, all the exposed adults were removed and progeny production on treated grains was assessed 45 and 90 d later. Insecticidal efficacy of SilicoSec against the rice weevil was highly affected by grain type, exposure interval and dose rate. In all grains tested, longer exposure intervals increased weevil mortality. The efficacy of SilicoSec on maize was not satisfactory, given that after a 14 d exposure at the highest dose rate the mortality did not exceed 65%. Moreover, progeny production on treated maize was high, regardless of the dose rate. On the other hand, 100% of weevils were dead on barley treated with the two highest dose rates of SilicoSec, after a 7 d exposure. However, a complete suppression of progeny production on treated barley was not achieved, even at the highest dose rate. A satisfactory level of protection was recorded on paddy rice treated with 1 and 1.5 g of SilicoSec/kg. At these two rates, all adults were dead after a 7 d exposure, and no progeny were produced during the 90 d incubation period. In contrast, the mortality on peeled rice treated with 1.5 g of SilicoSec/kg did not reach 100%, even after 14 d of exposure, and a high number of progeny were recorded.  相似文献   

3.
Laboratory bioassays were conducted to evaluate the insecticidal effect of two pirimiphos-methyl formulations, an emulsifiable concentrate (EC) and a capsule suspension (CS) against adults of Sitophilus oryzae, Rhyzopertha dominica and Tribolium confusum in wheat, maize and rice. Pirimiphos-methyl was applied at two dose rates, 2 and 4 ppm, and adult mortality was measured after 2, 7, 14 and 21 days of exposure in the treated commodity. Progeny production was assessed 65 d after the removal of the parental adults. S. oryzae adult survival was significantly higher in rice than in wheat and maize, whereas T. confusum mortality was significantly higher in maize than in the other grains. From the species tested, the most susceptible species was S. oryzae, for which mortality reached 100% after 7 days of exposure in treated wheat and maize, followed by T. confusum and R. dominica. Progeny production was significantly suppressed by pirimiphos-methyl in the case of S. oryzae, but not in the case of R. dominica. In general, only few differences in performance between the EC and the CS formulation were detected. We conclude that the type of grain commodity significantly affects mortality after the application of the two pirimiphos-methyl formulations tested, but this effect is species-dependent.  相似文献   

4.
We investigated the application of phosphine at low pressure for various exposure durations against major stored-product insects in a commercial dried fig processing facility in Central Greece. Trials were carried out inside a chamber, in which phosphine, in the form of aluminium phosphide pellets, was introduced with the use of a phosphine generator. The generator unit was also equipped with a vacuum pump to achieve low pressure inside the chamber. The chamber was filled with pallets with boxes containing figs. The insects tested were Tribolium confusum (all life stages), Ephestia elutella (eggs and larvae), Sitophilus oryzae (adults), Sitophilus granarius (adults), Rhyzopertha dominica (adults), Oryzaephilus surinamensis (adults) and Prostephanus truncatus (adults). Moreover, wheat grains containing immature stages of S. oryzae were also used. All insect-life stage combinations were exposed to phosphine at low pressure for 18, 48 and 72 h. In most cases, significant differences in mortality of insects treated with phosphine at low pressure compared to the control treatments were recorded. However, complete control (100%) was recorded only in the case of O. surinamensis adults and T. confusum larvae after exposure for 48 and 72 h, respectively. We conclude that the combined application of phosphine and low pressure at short exposure durations (up to 72 h) cannot provide sufficient control at least against the stored-product insect species and life stages tested in the present study.  相似文献   

5.
Diatomaceous earth (DE) deposits from regions of central and southeastern Europe were evaluated for their insecticidal efficacy against Sitophilus oryzae (L.) (Coleoptera: Curculionidae), Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) and Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) in comparison with the commercially available DE formulation SilicoSec. The effects of temperature, RH, grain commodity (wheat, barley, maize, rice), application method (spraying vs. dusting) were evaluated. FYROM, a DE from the Former Yugoslavian Republic of Macedonia, was the most effective of the DE deposits for grain treatment, whereas the least effective was from Greece (named Crete). However, for surface treatment, Slovenia was the most effective followed by Elassona 1 and Begora. Increase of temperature increased DE efficacy, while the reverse was noted with the increase of RH. Furthermore, the DEs were more effective in barley or wheat than in maize or rice. Neither the mined DEs nor SilicoSec were able to suppress progeny production of the tested species after previous exposure on the treated commodities. Generally, dust application of DEs was more efficacious than spraying against S. oryzae and T. confusum. However, spraying of wheat significantly reduced the bulk density (test weight) compared to dusting. For surface treatment, after 1 d of exposure, Slovenia was the most effective of the mined DEs followed by Elassona 1 and Begora, whereas after 6 d of exposure the mortality was almost complete (>99%) with all three DEs. More than 6 d of exposure were required for an effective control of T. confusum adults with the remainder of the mined DEs.  相似文献   

6.
Two series of laboratory bioassays were carried out in order to evaluate the effect of the simultaneous presence of two insect species inside the experimental vials and the effect of different sizes (50, 65, 90, 145 mm in diameter) of experimental vials on the efficacy of diatomaceous earth (DE) formulations as wheat (Triticum durum Desf.) protectants. Three DE formulations were tested; Insecto, SilicoSec and one DE enhanced with pyrethrum, PyriSec. In a third series of bioassays the influence of application technique of DE formulations in wheat and maize (Zea mays L.) on their insecticidal efficacy was also evaluated in the laboratory. Two DE formulations were tested; SilicoSec and Protect-It. The application technique was based on the duration of admixing (0.5 or 3 min) and surface treatment (without admixing) of DE formulations in grain. In all series of bioassays three species were tested; Sitophilus oryzae (L.) (Coleoptera: Curculionidae), Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) and Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae). Significant differences were noted in mortality levels of the tested species among the three DE formulations and among doses for the simultaneous presence of two insect species in all combinations and the different size of vials. In contrast, no significant differences were found in the mortality levels among the adult densities of any of the insects tested. The progeny production was low for all tested species. The increase of diameter of vials used in the bioassays decreased the mortality of S. oryzae and T. confusum adults significantly whereas no significant differences were noted for R. dominica adults. The increase of dose and exposure interval reduced differences of R. dominica adult mortality in admixture durations in the case of wheat. For S. oryzae, no significant differences in adult mortality in maize were found among admixture durations while significant differences were detected in wheat.  相似文献   

7.
The insecticidal and residual effect of spinosad on wheat, maize and barley grain was evaluated in the laboratory against adults of Sitophilus oryzae (F.) (Coleoptera: Curculionidae), Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), Tribolium confusum (DuVal) (Coleoptera: Tenebrionidae), Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae) as well as against larvae of T. confusum. Spinosad was applied as a solution to 2 kg lots of each commodity at three concentrations, 0.1, 0.5 and 1 ppm, and the treated grain quantities were kept at 25 °C and 65% RH. Samples were taken from each concentration-commodity combination at the day of storage and every 30 d for 6 consecutive months (6 bioassays). The test species were exposed for 14 d to the samples and mortality and reproduction were assessed over this exposure interval. With the exception of T. confusum, 1 ppm of spinosad was highly effective against the remainder of the tested species and provided protection for a period of storage at least 4 months. Although in general, spinosad performance was not very much affected by the grain type, efficacy on maize was less stable over the 6-month period of storage and declined sooner compared to the other commodities. Spinosad almost suppressed progeny production of R. dominica during the storage period, but did not suppress progeny of the other species, since progeny were recorded even 30 d post application especially with the lowest of the tested concentrations. The results of this study indicated that spinosad may provide suitable protection for 6 months against S. oryzae or R. dominica, but is not suitable for long-term protection against T. confusum or C. ferrugineus.  相似文献   

8.
Several pyrrole compounds exhibit insecticidal properties against a wide range of insect pest species. In the present work, the insecticidal effect of the two new pyrrole derivatives, ethyl 3-(benzylthio)-4,6-dioxo-5-phenyl-2,4,5,6-tetrahydropyrrolo[3,4-c]pyrrole-carboxylate (3i) and isopropyl 3-(benzylthio)-4,6-dioxo-5-phenyl-2,4,5,6-tetrahydropyrrolo[3,4-c]pyrrole-carboxylate (3k) were studied as stored-grain protectants (maize and barley) against two major stored-product insect species, the confused flour beetle, Tribolium confusum Jaquelin du Val (Coleoptera: Tenebrionidae) adults and larvae and the Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) larvae at three doses (0.1, 1 and 10 ppm) and five exposure intervals (1, 2, 7, 14 and 21d). All T. confusum adults were dead at all doses on barley treated with 3i after 21d of exposure, while for 3k mortality was >92%. Progeny production was very low (≤1 individual per vial) at all doses for both pyrrole derivatives. Mortality of T. confusum larvae was not complete with any dose of both pyrrole derivatives but it exceeded 96% with 3k at 10 ppm after 21d of exposure on maize. For barley, all exposed larvae were found dead at all doses of both pyrrole derivates after 7d of exposure. Mortality of E. kuehniella larvae was complete at 1 and 10 ppm of 3i and all doses of 3k at 7d of exposure. After 14d of exposure, all E. kuehniella larvae were dead at 0.1 ppm of 3i. The results of the present study indicate that the tested compounds have elevated insecticidal effect against both species tested on certain combinations of dose, exposure interval and type of commodity.  相似文献   

9.
Powders prepared from sweetflag Acorus calamus rhizomes collected at both high (1700 m) and low (900 m) altitude in Eastern Nepal were admixed with wheat at concentrations in the range 0.05–2% w/w and the wheat infested with Sitophilus oryzae or S. granarius adults. Following a 7 day incubation, the mortality of both species was significantly lower at 20 °C than at 30 °C, and the material collected from high altitude was slightly less toxic than that from low altitude. The moisture content of the wheat (14 or 17%) and the part of the rhizome used to prepare the powder (young or mature growth) had no apparent effect on the toxicity of the preparation. Sitophilus granarius (L.) adults were more tolerant of the material than S. oryzae (L.), while the converse was true for larvae developing in treated grain. An admixture rate of approximately 2% w/w admixed rhizome powder was required to give complete kill of adults of both species following 7 days exposure at 20 °C, while a concentration of 1% w/w either prevented the emergence of adults or killed them rapidly following emergence when wheat containing eggs of either species was incubated for 7–8 weeks at 30 °C.

The β-asarone content of the rhizome powders was determined by GC-MS as 6.4 and 4.7% w/w (mature section of rhizomes collected at high and low altitudes, respectively) and 3.6 and 4.0% w/w (young sections of rhizomes collected at high and low altitudes, respectively). It is anticipated that, under field conditions and in the temperature range 20–30 °C, the initial residue of approximately 1300 mg/kg β-asarone required to disinfest wheat containing these weevil species would decline rapidly due to evaporation.  相似文献   


10.
In laboratory experiments toxicity of acetone, acrolein and carbon dioxide were investigated against 4 species of stored-product insects. In all experiments, acrolein was the most toxic compound to the tested insects. In empty-space trials, estimated LD50 values of acrolein for adults of Tribolium castaneum (Herbst) (Tenebrionidae), Rhizopertha dominica (F.) (Bostrychidae), Sitophilus oryzae L. (Curculionidae) and Oryzaephilus surinamensis L. (Silvanidae) were 7.26, 6.09, 6.37 and 5.65 microl L(-1), respectively. Penetration tests revealed that acetone and acrolein vapors could penetrate into the wheat mass and kill concealed insects in interkernel spaces. Comparison of LD50 values of acrolein between empty-space tests and penetration experiments indicated that the increase in penetration toxicity was 4.96, 4.54, 3.64 and 3.43-fold for T. castaneum, R. dominica, S. oryzae and O. surinamensis, respectively. The effect of carbon dioxide on the toxicity of acrolein and acetone was synergistic. In the hidden infestation trials, the acrolein vapors destroyed the developmental stages of S. oryzae concealed inside the wheat kernels and resulted in a complete control with concentration of 80 microl L(-1) for 24 h and subsequently observed during 8 weeks after the exposure. Wheat germination and plumule length was reduced following exposure to all doses of acrolein. Acetone and carbon dioxide were harmless to wheat seed viability. The mixture of carbon dioxide with acrolein can be considered as a potential fumigant for replacing methyl bromide or phosphine under ambient storage conditions specifically in empty-space fumigations.  相似文献   

11.
As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F1 progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC50 of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC50 of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus.  相似文献   

12.
The objectives of this study were to evaluate the efficacy of Sunn pest entomopathogenic fungi collected from wheat fields and overwintering sites in Syria and characterize them under different temperature regimes. Eleven isolates of Beauveria bassiana (Bals.) Vuil. were included in this study: five were isolated from overwintered adults of Sunn Pest, Eurygaster integriceps Puton and six from nymphs and new adults in wheat fields. Growth rate and conidial production were tested at 15, 20, 25, 30 and 35 degrees C. Results showed that highest growth rate of tested fungal isolates was at 25 degrees C, except for the two isolates SPDR-1 and SPDR-2 which exhibited highest growth rate at 20 degrees C. The highest production of conidia of tested fungal isolates was at 20 degrees C, except for isolates SPSR-1, SPSQ and SPSS which exhibited higher production at 25 degrees C. Virulence test of the tested fungal isolates on overwintered adults Sunn Pest showed that percent mortality after 14 days ranged between 86-100%.  相似文献   

13.
苯并噻二唑诱发水稻对白叶枯病的系统获得抗性   总被引：17，自引：2，他引：15  
用苯并噻二唑（benzothiadiazole, BTH)(0.5 mmol/L）、水杨酸（1 mmol/L）、硝酸镍(0.5 mmol/L)、多效唑（300 mg/L）和烯效唑（40 mg/L）处理4叶1心期稻苗后接种白叶枯病菌,病斑长度明显降低。BTH对白叶枯病病菌生长无明显抑制作用。BTH诱发稻苗对白叶枯病抗性的最佳浓度为0.5~1 mmol/L;在诱发处理和接种之间至少需要2 d才能诱导抗性,间隔7 d的诱导抗性效果最好,诱导抗性的持久期至少15 d。BTH处理稻苗第2叶,可使未处理的第3和第4叶上也表现出诱导抗性,但处理后至少需要24~36 h上部叶片才表现出诱导抗性。结果表明,BTH诱导对白叶枯病的抗性是一种系统获得抗性反应。  相似文献   

14.
The effectiveness of vacuum (V) treatment alone and in combination with an oxygen absorber (V + A) for suppression of grain infestation by Sitophilus granarius L. were compared under laboratory conditions. The effectiveness of the treatment methods was evaluated at different temperatures (15, 25 °C) and exposure times (7, 14, 21, 28 days). We evaluated both the effects on adults present in grain interspaces and hidden infestations within the kernels in terms of treatment time separately. Adults of S. granarius present in grain interspaces were more susceptible to both treatments than hidden infestations developing within kernels. At 25 °C, total mortality of adults in grain interspaces was achieved after 10 days of exposure whereas total suppression of hidden infestations was achieved after 3 weeks. Higher temperature and longer exposure correlated with a greater effectiveness of the tested treatments. The addition of an oxygen absorber to the vacuum treatment (V + A) showed the general tendency of improving the effectiveness of the vacuum treatment on suppression of hidden infestations; significant differences between the V + A and V treatments were prominent primarily at the lower temperature tested. Reduction of hidden infestation was achieved after 3 weeks of exposure to V + A treatment (99.8%) and after 4 weeks of V treatment (95.8%) at 15 °C.  相似文献   

15.
The health-promoting properties of the grains of common wheat (Triticum aestivum L.) are associated with the presence of unique phytochemicals. This study determines the profile of alkylresorcinols (ARs) and benzoxazinoids (BXs) in T. aestivum spring and winter cultivars grown in Poland under the two different production systems: conventional and organic. Wheat grain extracts were subjected to qualitative and quantitative UPLC-UV-MS/MS analyses. The ARs profile consisted of five 5-n-alkylresorcinol derivatives, among which 5-n-heneicosylresorcinol (C21:0) and 5-n-nonadecanylresorcinol (C19:0) predominated; while six different BXs were determined in hydrothermally treated grains. Our research shows significant differences in the contents of ARs and BXs among wheat cultivars, as well as the two production systems used. Organically grown varieties had their total contents of ARs and BXs significantly higher than those grown conventionally. Another aim of the study was to determine the antioxidant capacity of alkylresorcinol extracts from tested wheat cultivars. The quantitative TLC-DPPH• method for determining the antiradical capacity of wheat ARs extracts was developed. We observed a positive relationship between the free radical scavenging activity of extracts and the total amount of ARs. The biological activity research is important for developing value-added wheat cultivars, having an improved profile and composition of nutritional substances.  相似文献   

16.
报道了黑龙江省水稻小球菌核菌无性世代的分生孢子双曲孢属 (Nakataea sigmoidea Hara) ,并对其人工培养条件进行了初步探讨。结果表明 ,在黑暗条件下 ,不同的营养条件、环境条件及培养方式病原菌均不能产生分生孢子 ;在自然光条件下 ,病原菌的菌核和菌丝在水琼脂培养基上均可产生分生孢子。生长物质和微量元素均不能促进孢子产生。C/ N对菌核萌发直接产生分生孢子有影响 ,其中 C/ N为 10 / 1时产孢率最高 ,达 5 4 .2 3%。  相似文献   

17.
The effects of cycloxaprid (a modified neonicotinoid insecticide) and buprofezin (a thiadiazine insecticide) on mortality of the white-backed planthopper (WBPH), Sogatella furcifera, were determined in laboratory assays. Cycloxaprid killed WBPH nymphs and adults but buprofezin killed only nymphs, and cycloxaprid acted faster than buprofezin. One day after infestation, mortality of third-instar nymphs was >65% with cycloxaprid at 125 mg liter−1 but was <38% with buprofezin at 148 mg liter−1. By the 4th day after infestation, however, control of nymphs by the two insecticides was similar, and cycloxaprid at 125 mg liter−1 caused ≥80% mortality of adults but buprofezin at 148 mg liter−1 (the highest rate tested) caused almost no adult mortality. LC50 values for cycloxaprid were lowest with nymphs, intermediate with adult males, and highest with adult females. Although buprofezin was slower acting than cycloxaprid, its LC50 for nymphs 5 d after infestation was 3.79-fold lower than that of cycloxaprid. Mean carboxylesterase (CarE) specific activity of nymphal WBPH treated with cycloxaprid and buprofezin was higher than that of control, but there was no significant difference between cycloxaprid and control (no insecticide), and it was significantly higher for buprofezin than those of cycloxaprid and control. For glutathione S-transferase and mixed function oxygenase, the specific activity of nymphal WBPH treated with buprofezin was significantly higher than those of cycloxaprid and control, too.  相似文献   

18.
Extracts of leaves of Schinus molle Rev L. (Anacardiaceae) obtained with water or ethanol as solvents were evaluated in the laboratory for their insecticidal effect on adults of the elm leaf beetle, Xanthogaleruca luteola Müller (Coleoptera: Chrysomelidae), at 2.5, 3.0, 4.3, and 5.6% w/v for the aqueous extracts and, 2.0, 2.5, 3.5, 4.3, and 4.7% w/v for the ethanol extracts. The extracts were applied onto leaves of elm trees (Ulmus sp., Ulmaceae) to observe the feeding of adults, and later their effectiveness and to obtain the LC50. Both extracts were effective and caused mortalities greater than 97% with the ethanol extract at the two highest concentrations (4.3 and 4.7% w/v), and near 27% with water at 4.3 and 5.6% w/v. The LC50 of the ethanol extract, calculated through Probit analysis, was 1.88% w/v on the 2nd day, lower than the LC50 of 8.52% w/v on the 4th day achieved by the aqueous extract. Additionally, the antifeeding effect of both extracts on adults was determined. The aqueous extract inhibited feeding completely (100%), whereas the ethanol extract did not cause any antifeeding effect.  相似文献   

19.
Tyrophagus putrescentiae on rapeseed was exposed to a sub-lethal residue of 0.15 μg of bifenthrin per 100 g of rapeseed over 147 days, i.e. 14 generations. Every 21 days, samples of mites were collected and mortality was evaluated using a bifenthrin-treated filter paper bioassay. The sampled mites were also introduced onto newly-treated seeds. The susceptibility of the mites to bifenthrin remained similar after pre-exposure for all intervals from 21 to 147 days. The, LD50 ranged from 0.16 to 1.14 μg of bifenthrin per cm2 of filter paper. After 147 days, the rates of population increase and respiration of mites pre-exposed to the sub-lethal dose of bifenthrin were evaluated on bifenthrin treated (sub-lethal dose) and untreated rapeseed. Pre-exposure to bifenthrin had no significant effect on respiration, but influenced the rate of increase of mites on rapeseed: The mites pre-exposed to the sub-lethal dose of exhibited a higher rate of increase on the bifenthrin-treated rapeseed than on untreated rapeseed. Thus a decrease in the susceptibility of T. putrescentiae to bifenthrin with selection on a sub-lethal bifenthrin dose on rapeseed during up to 147 days of exposure during which the mite completed approximately 14 generations was not observed. However, the sub-lethal doses of bifenthrin stimulated the population growth and metabolic activity of the mites. Under such conditions, the production of hazardous proteins will probably be higher than on untreated rapeseed.  相似文献   

20.
为对嘧菌酯在小麦生产上应用的安全性进行评价,采用田间试验,使用QuEChERS方法进行样品前处理,气相色谱法电子捕获检测器进行定量分析,对嘧菌酯在小麦中的残留动态及最终残留量进行了研究,并对小麦籽粒中嘧菌酯残留量进行了膳食摄入风险评估。结果表明,在0.01~1.0mg·kg~(-1)添加水平范围内,嘧菌酯在植株、籽粒空白添加的平均回收率为87.9%~108.4%,相对标准偏差为1.1%~6.2%,其最小检出量为5×10~(-12)g,植株、籽粒中的最低检测浓度均为0.01mg·kg~(-1)。该检测方法准确度、灵敏度高,重复性好,可满足嘧菌酯在小麦植株及籽粒中的残留分析要求。消解动态研究表明,嘧菌酯在小麦植株中的消解半衰期为3.3~4.3d。最终残留试验表明,20%嘧菌酯可湿性粉剂按施药剂量180、270g a.i.·hm~(-2),连续喷药2~3次,施药间隔7d,药后7、14、21d,嘧菌酯在小麦籽粒中的最终残留量均≤0.354mg·kg~(-1)。普通人群嘧菌酯的国家估算每日摄入量是2.43mg,占日允许摄入量的19.0%左右,因此,按本试验方式进行施药,不会对一般人群健康产生不可接受的风险。  相似文献   

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