高效液相色谱-串联四级杆质谱测定黄瓜和土壤中乙嘧酚磺酸酯的残留

建立了高效液相色谱-串联四级杆质谱测定黄瓜和土壤中的乙嘧酚磺酸酯的农药残留方法,样品经乙腈提取,氨基柱净化,应用高效液相色谱-串联四极杆质谱仪进行测定,外标法定量。采用该法对黄瓜和土壤中的乙嘧酚磺酸酯农药进行测定,平均回收率为93.69～104.93%之间,相对标准偏差为3.42～7.47%,检出限为0.001 6mg/kg,线性范围为5～320ng/mL,相关系数为0.999 5.结果表明：该法可用于黄瓜和土壤中乙嘧酚磺酸酯的测定。     

超高效液相色谱串联质谱测定大豆和土壤中精喹禾灵的残留分析方法

建立超高效液相色谱-电喷雾串联四极杆质谱测定大豆和土壤中精喹禾灵残留分析方法,该方法具有快速、准确、灵敏度高,检测限低等特点。样品经固相萃取净化,应用超高效液相色谱-电喷雾串联四极杆质谱仪选择反应监测(SRM)定量法检测精喹禾灵。结果表明,该方法对精喹禾灵的最低检出限LOD为0.65μg/kg。在0.649～324.600μg/L线性范围内,相关系数为0.999 9,回收率在82.42～99.61%之间,相对标准偏差<5%(n=5)。     

QuEChERS-超高效液相色谱-串联质谱法同时测定草莓中甲基硫菌灵、多菌灵和乙嘧酚残留

建立了QuEChERS-超高效液相色谱-串联质谱同时检测草莓中甲基硫菌灵、多菌灵和乙嘧酚残留的方法。样品经0.5%甲酸-乙腈提取,QuEChERS方法净化,以Agilent XDB-C18色谱柱(2.1 mm×150 mm,3.5 μm)进行UPLC分离,采用三重四极杆串联质谱以正离子多反应监测模式(MRM)进行测定。结果表明:在20~1 000 μg/L范围内,甲基硫菌灵、多菌灵及乙嘧酚的质量浓度与其相应的峰面积间呈现良好的线性关系,相关系数均大于0.997 8。在50~500 μg/kg添加水平下,草莓中甲基硫菌灵、多菌灵和乙嘧酚的平均回收率在86%~109%之间,相对标准偏差(RSD)在1.9%~13%(n=5)之间,检出限分别为2.5、0.50和1.0 μg/kg,定量限均为50 μg/kg。该方法样品前处理过程简单快速,分析时间短,灵敏度、准确度及精密度均符合农药残留检测要求,适用于草莓中甲基硫菌灵、多菌灵和乙嘧酚残留的检测。     

超高效液相色谱串联质谱法测定马铃薯和土壤中氟啶胺残留

建立超高效液相色谱-电喷雾串联四极杆质谱快速测定马铃薯和土壤中氟啶胺残留的分析方法。样品经固相萃取净化,以液相色谱-质谱联用仪测定和确证,外标法定量。结果表明。该方法对氟啶胺的最低检出限为8μg／kg。在8．150-521．6μg／L线性范围内,相关系数为0．9999,回收率在81．96～116．66％之间,相对标准偏差〈10％（n=5）。     

乙嘧酚磺酸酯对黄瓜白粉病菌的毒力测定

以温室盆栽生物测定法,测定乙嘧酚磺酸酯对黄瓜白粉病菌的毒力。结果表明:乙嘧酚磺酸酯的EC50值为5.61μg/g,嘧菌酯的EC50值为7.16μg/g,乙嘧酚磺酸酯对嘧菌酯的T50值为127.6,说明乙嘧酚磺酸酯对黄瓜白粉病具有显著的抑制活性。     

超高效液相色谱-串联质谱法测定黄瓜及番茄中异菌脲残留

采用分散固相萃取(QuEChERS)为样品前处理方法,建立了超高效液相色谱-串联四极杆质谱(UPLC-MS/MS)快速同时检测黄瓜及番茄中异菌脲的残留分析方法。样品经乙腈提取,C18分散固相(dSPE)净化后,应用超高效液相色谱-电喷雾串联四级杆质谱仪,多反应监测模式(MRM)检测,外标法定量,结果显示,异菌脲在黄瓜和番茄基质中的线性关系良好,在0.02~1mg/L添加水平范围内,异菌脲在黄瓜和番茄中的平均回收率分别为82.7%~91.9%和89.8%~90.5%,相对标准偏差分别为4.7%~7.7%和4.8%~7.2%,最低检出浓度(LOQ)均为0.02mg/kg。     

超高效液相色谱-串联质谱法测定草莓中唑螨酯残留

建立了超高效液相色谱-三重四级杆串联质谱(UPLC-MS/MS)检测草莓中唑螨酯残留分析方法。样品采用乙腈提取,石墨化碳黑氨基复合柱净化,超高效液相色谱分离,多反应监测模式测定,外标法定量。结果表明,在0.1～100μg/L浓度范围内,线性关系良好,R~20.998 5,平均回收率在94.0%～98.0%之间,相对标准偏差5%(n=6),方法的检出限为0.02μg/kg。可用于草莓中唑螨酯残留检测。     

超高效液相色谱串联质谱测定芹菜中味鲜胺、噻虫嗪等5种农药残留量

建立超高效液相色谱-电喷雾串联四极杆质谱快速测定芹菜中咪鲜胺、噻虫嗪、吡虫啉、啶虫眯、烯酰吗啉残留的分析方法,样品经固相萃取净化,以液相色谱-质谱联用仪测定和确证,外标法定量。本方法具有快速、准确、灵敏度高,检测限低等特点。     

乙嘧酚磺酸酯·吡唑醚菌酯30%微乳剂高效液相色谱分析方法

本方法采用高效液相色谱法,以甲醇-水溶液作为流动相,用HyPersil BDS C18250mm×4.6mm.10μm柱和紫外检测器,分析乙嘧酚磺酸酯.吡唑醚菌酯30%微乳剂。结果表明:乙嘧酚磺酸酯,吡唑醚菌酯的标准偏差分别为:0.13和0.16;变异系数分别为:0.36%和0.39%;平均回收率分别为:99.1%和99.2%。     

超高效液相色谱-串联质谱测定草莓中醚菌醋残留量

建立了草莓中醚菌酯残留检测的超高效液相色谱-串联质谱方法(UPLC-MS/MS)。草莓样品经乙腈提取,石墨化碳黑氨基复合柱(ProElut CARB/NH_2)净化,以甲醇和0.1%甲酸水溶液作为流动相洗脱,采用电喷雾离子源正离子模式(ESI~+),多反应监测(MRM)方式进行采集,外标法定量。结果表明,该试验方法简单,灵敏,选择性好,精密度高,醚菌酯在0.50～50.00μg/L浓度范围内呈现良好的线性关系,相关系数R~20.99,方法检出限为0.10μg/kg,测定下限为0.50μg/kg。在0.50～50.00μg/kg范围内,回收率(92.2%～95. 4%)、精密度(2.57%～5.34%)和提取回收率(92. 19%～95. 41%)均满足分析方法要求。     

Richtlinien der Verbände des ökologischen Landbaus zum Vorratsschutz

Zusammenfassung Verbände des ökologischen Landbaus wie z. B. Bioland, Gäa, Demeter; Naturland, Ernte für das Leben oder Bio Suisse beschränken ihre Mitglieder bei der Wahl von Vorratsschutzmaßnahmen. Vorrang besitzen Maßnahmen zur Vermeidung von Schädlingen gegenüber Bekämpfungsmaßnahmen. Fallen müssen zur Befallsüberwachung eingesetzt werden, um einen Befall durch Vorratsschädlinge frühzeitig zu erkennen. Diese Maßnahmen sollen den weitgehenden Verzicht auf chemisch-synthetische Mittel ermöglichen. In diesem Beitrag werden die Empfehlungen der Verbände mit den derzeit verfügbaren chemischen Mitteln für den Vorratsschutz abgeglichen. Erfahrung in der praktischen Umsetzung von physikalischen und biologischen Verfahren werden diskutiert und Defizite bei der Befallsüberwachung und Bekämpfung beschrieben.     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

Development of protocols for detection of Colletotrichum acutatum and monitoring of strawberry anthracnose using real-time PCR

Real-time PCR (TaqMan®) assays were developed for the specific detection and discrimination of Colletotrichum spp., C. acutatum and C. gloeosporioides causing anthracnose in strawberry using the most divergent area of the internal transcribed spacers (ITS1 and ITS2) and 5·8S ribosomal RNA (rRNA) gene region. The specificity of the new assays was tested using DNA from six species of Colletotrichum and nine fungal species commonly found associated with strawberry material, and additionally by comparing the sequences with those from databases using a blast search. The sequences only showed identity with homologous sequences from the desired target organisms. The new assays were 10–100 times more sensitive than conventional PCR methods previously published for the diagnosis of strawberry anthracnose. When real-time PCR was compared with ELISA methods, PCR improved the sensitivity of the identification by obtaining positive results for samples of strawberry plant material that tested negative with ELISA. The development of C. acutatum was monitored using artificially infected strawberry crowns from two strawberry cultivars (Camarosa and Ventana) and a real-time PCR assay specific for this species between January and June 2006. The amount of C. acutatum detected using real-time PCR varied significantly by month ( P  < 0·001), but not by cultivar ( P  = 0·394). The new assays were shown to be useful tools for rapid detection and identification of these pathogens and to allow rapid and accurate assessment of the casual agents of anthracnose in strawberry.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.     

Plant–herbivore asynchrony necessitates augmentative releases of the exotic beetle,Zygogramma bicolorata,to enhance the biological control of P arthenium hysterophorus

Systematic information on the quantitative impact of Z ygogramma bicolorata on the biology of P arthenium hysterophorus is crucial as the seeds of this weed continue to germinate from the accumulated soil seed bank throughout the year in the form of different germinating flushes, while the activity of the beetle ceases during winter as it enters diapause. Therefore, plant–herbivore interactions need to be explored to develop predictions of the overall impact of the introduced beetle on the weed. The findings revealed that defoliation by Z . bicolorata had a significant impact on the plant height, density and flower production in flushes F ₃, F ₄ and F ₅, but not in F ₁ and F ₂ that exhibited longer periodicity, profuse branching, a longer flowering period and maximum flower production and contributed mostly to the existing seed soil bank. Therefore, total depletion of the existing soil seed bank was not possible. Consequently, the effect of augmentative field releases of laboratory‐reared beetles was explored on F ₁ and F ₂ in February for three consecutive years (2011–2013). Before initiating the trial, random soil samples were taken from the plots that were assigned to the paired treatments (i.e. with the beetle and without the beetle [insecticide‐treated]) and it was found that the seed bank in those samples did not differ. The single release of Z . bicolorata adults at five per plant at the six‐leaf stage significantly reduced the soil seed bank, compared to without the biocontrol agent, irrespective of the flushes at the end of the season.     

Effects of the saprophytic leaf mycoflora on growth and productivity of winter wheat

The effects of the saprophytic mycoflora and its interference with cereal aphids on growth and yield of winter and spring wheat was studied in field experiments in 1980, 1981 and 1982.Yields varied between 5000 and 8000 kg dry matter of kernels per ha. The effect of the saprophytic mycoflora on yield was determined in different treatments: A) no control measures against cereal aphids and saprophytic and necrotrophic fungi, B) no control of cereal aphids, control of saprophytic and necrotrophic fungi, C) control of cereal aphids and control of saprophytic and necrotrophic fungi, D) control of cereal aphids and stimulation of saprophytic mycoflora and E) control of cereal aphids, no control of saprophytic and necrotrophic fungi nor stimulation of saprophytic mycoflora.Considerable differences in top densities of saprophytic mycoflora (10 times as large in A and D as in B and C) were determined. The consequences of these differences for the growth and productivity of wheat were minor. A negative effect of saprophytic mycoflora on the yield could not be detected in 1981 and 1982, whereas a small positive significant effect was found in 1980. This stimulation may have been due to competition between necrotrophic fungal pathogens and saprophytic mycoflora. As a result of favourable weather conditions necrotrophic fungal pathogens were very numerous in 1980 and could form an important yield reducing factor. Yield levels may effect the importance of the necrotrophic and saprophytic mycoflora as yield reducing factors. Additionally, in the presence of aphid honeydew captafol was found to be relatively ineffective against saprophytic fungi.