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<正>由中国化工信息中心胡笑形教授主译,英国农作物保护委员会(The British Crop Protection Council,BCPC)出版的The Pesticide Manual(16th edition)中译本《农药手册》已经完稿,将于2014年下半年由化学工业出版社正式出版发行。The Pesticide Manual是一本世界公认的权威性农药工具书。于1968年首次出版,目前已发行至第16版。该手册的特点:1涵盖的农药品种新且全。与15版(2009年)相比,16版又增加了40多个新农药化合物。其收录品种的选择是动态的,即根据品种的性能、安全环保、市场变化等因素决定取舍。本版既包含新一代农药品种,也保留了经过重新登记、目前仍适合农药需要的早期发明。正文中收录了920个农药品种,附录中收录了710个农药品种。2系  相似文献   

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Abstract: The adult male of dracunculoid nematode Ichthyofilaria argentinensis Incorvaia, 1999 (Guyanemidae) is described for the first time based on specimens found in the swimbladder of its type host, Merluccius hubbsi Marini (Merlucciidae), caught off the coast of Buenos Aires, Argentina (western Atlantic Ocean). In addition, the males of Ichthyofilaria bergensis (Wülker, 1930) K?ie, 1993 are redescribed from specimens collected from the body cavity and visceral surface of Molva macrophthalma (Rafinesque) (Lotidae) caught in the western Mediterranean Sea, off the coast of Sardinia. Light and scanning electron microscopy examinations revealed some new morphological features for the genus, such as a pair of deirids located near the end of muscular oesophagus, the body wall conspicuously twisted immediately anterior to the cloaca, the presence of a copulatory plate, one pair of adcloacal papillae and a pair of phasmids situated on the posterior half of the tail. On the basis of this material, the generic diagnosis of Ichthyofilaria is modified to include some of these newly observed features, as well as to indicate the absence of spicules. The diagnosis of Guyanemidae is extended to include that a copulatory plate and/or two spicules may be present as characteristics for this family.  相似文献   

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Fusarium head blight (scab) epidemics of wheat occurred in uawy (Northern Poland) during 1998 and in Wielkopolska (West) and in Southern regions of Poland in 1999. Four species were identified in wheat heads with scab symptoms: Fusarium culmorum, Fusarium graminearum, Fusarium avenaceum and Microdochium nivale. A significant increase in the frequency of F. graminearum (between 23% and 38%), was observed, compared to about 10% during the previous decade. The mycotoxins deoxynivalenol (DON), nivalenol (NIV) and moniliformin (MON) in amounts up to 24.3, 14.2 and 1.72mgkg–1respectively, were identified in kernels samples.  相似文献   

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研究报告用赤眼蜂蛹饲养捕食性瓢虫的初步试睑………………··曹爱华 张良武(1):1—5管式肿腿蜂离体培养研究……………………·李 理 温硕洋 谢以权等(二);6—7温度和雨量对玉米螟幼虫天敌寄生的影响…………………… 。…………………··陈永明 傅达昌 朱 f4培(1):8—9武汉地区蔬菜害虫捕食性蜘蛛初步研究……。··张 原 王小平 夏文胜(l):10—13阶轮枝霉的培养性状和田间发生规律………………………··,……岑定浩(1):14—16用自组织人工神经网络预判昆虫适生区……蔡娱东 杨 兵 吴有红等(1);17-20影响昆虫病原线虫对猪场蝇姐防效的…  相似文献   

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The study determined the effectiveness of nC24 and nC27 petroleum spray oils (PSOs) to reduce oviposition of Ostrinia nubilalis and survival of O. nubilalis eggs and Trichogramma brassicae adults. Under choice and no-choice tests, maize treated with 3, 5 and 10% (v/v) of both oils deter O. nubilalis oviposition on maize. The study also showed that treatment of 1 – 3-day-old O. nubilalis eggs with 1 and 2% (v/v) nC24 oil caused 6% mortality compared with 99.5% when treated with 3, 5 and 10% (v/v) oil. In contrast, treatment with 1 – 10% (v/v) nC27 oil caused 99% mortality. Trichogramma brassicae is a major parasitoid of O. nubilalis. The mortality of T. brassicae 24 h after exposure to maize sprayed with 2% (v/v) nC24 and nC27 oils was 8.3 and 12.7%, respectively. At 5% (v/v), the mortalities were 24.9 and 23.5%, respectively. Therefore, application of 3% (v/v) PSO may deter O. nubilalis egg lay, egg mortality and survival of T. brassicae on maize.  相似文献   

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A phytoplasma infecting alfalfa crops was detected and characterised in Argentina, the Argentinean Alfalfa witches′-broom (ArAWB) phytoplasma. Typical witches′-broom symptoms were observed in diseased alfalfa plants from fields of the ‘Cuyo’ region in the Andean midwest. Pleomorphic bodies were observed by electron microscopy in sieve tubes of the diseased plants. The results obtained from the sequence homology, similarity coefficients derived from RFLP of the 16S rDNA and phylogenetic analysis led us to include this phytoplasma in the 16Sr VII (Ash Yellows) group. However, the ArAWB phytoplasma showed several differences when compared to other members of group 16Sr VII. The RFLP analysis of partial 16S rRNA gene of two ArAWB isolates, digested with 16 restriction enzymes, showed differences between the ArAWB and the reference strain (AshY1T) in six enzyme patterns. Restriction patterns unique for the group and an exclusive HinfI restriction site were found in the ArAWB phytoplasma rDNA. Moreover, the similarity coefficients (0.92–0.86) were lower than those obtained among other group members. The significant differences detected suggested that this phytoplasma belonged to a subgroup different from those described so far. We propose therefore, that the ArAWB phytoplasma should be included in a new VII-C subgroup, closely related to the EriWB phytoplasma (VII-B) described in Brazil.  相似文献   

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The Central Tianshan Block is one of numerous microcontinental blocks within the Central Asian Orogenic Belt(CAOB)that overlies Precambrian basement rocks.Constraining the evolution of these ancient basement rocks is central to understanding the accretionary and collisional tectonics of the CAOB,and their place within the Rodinia supercontinent.However,to date,the timing and tectonic settings in which the basement rocks in the Central Tianshan Block formed are poorly constrained,with only sparse geochemical and geochronological data from granitic rocks within the northern segment of the block.Here,we present a systematic study combining U-Pb geochronology,whole-rock geochemistry,and the Sr-Nd isotopic compositions of newly-identified granitic gneisses from the Bingdaban area of Central Tianshan Block.The analyzed samples yield a weighted mean Neoproterozoic 206Pb/238U ages of 975-911 Ma.These weakly-peraluminous granitic rocks show a common geochemical I-type granite affinity.The granitic gneisses are calc-alkaline and enriched in large ion lithophile elements(LILEs)and light rare earth elements(LREEs),but they are depleted in high field strength elements(HFSEs);these characteristics are similar to those of typical subduction-related magmatism.All samples show initial(87Sr/86Sr)(t)ratios between 0.705136 and 0.706745.Values forεNd(t)in the granitic gneisses are in the range from-5.7 to-1.2,which correspond to Nd model ages of 2.0-1.7 Ga,indicating a role for Mesoproterozoic to Paleoproterozoic rocks in the generation of the granitic protoliths.The documented geochemical features indicate that the protoliths for the gneisses have a similar petrogenesis and magmatic source,which may reflect partial melting of thickened crust with the addition of small amounts of mantle-derived material.The Central Tianshan Block probably constitute part of an exterior orogen that developed along the margin of the Rodinian supercontinent during the Early Neoproterozoic and underwent a transition from subduction to syn-collision compression at 975-911 Ma.  相似文献   

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亚太地区植保委员会第16届会议于1989年9月26~30日在南鲜朝汉城的水原地区召开。参加这次会议的有14个成员国(或地区),即澳大利亚、孟加拉、印度、印度尼西亚、南朝鲜、马来西亚、新西兰、巴基斯坦、菲律宾、斯里兰卡、泰国;香港、澳门地区和越南。列席会议的观察员有中国、美国和日本3个国家。参  相似文献   

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Mamejvo (Enicostemma axillare Raynal) is a perennial herb with diversified health benefits. It was found to be affected by a witches?? broom disease under the field conditions at Anand, Gujarat, India. Affected plants were 53.33% reduced in height due to shortened internodes, leading to typical witches?? broom symptoms. Flower size was reduced significantly in the affected plants compared with the healthy ones and their petal color gradually turned green (virescence). Affected plants produced 2.5 times more dry herbage than the normal plants but with less active ingredient (swertiamarin). Symptomatic plants died early while root suckers from such plants failed to establish after transplanting. DAPI stained transverse sections of affected shoot tips showed the presence of discrete greenish fluorescence in the phloem cells under UV light. Amplification of 1.2?kb phytoplasma specific rDNA fragment from diseased tissue confirmed the presence of the pathogen. Further characterization of the pathogen through virtual rDNA?CRFLP pattern and rDNA sequence based phylogeny suggested that the pathogen, Enicostemma witches?? broom phytoplasma, belonged to 16SrII?CC group of ??Ca Phytoplasma aurantifolia??.  相似文献   

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Wang Y  Chen J  Zhu YC  Ma C  Huang Y  Shen J 《Pest management science》2008,64(12):1278-1284
BACKGROUND: In recent years, outbreaks of the brown planthopper, Nilaparvata lugens (Stål), have occurred more frequently in China. The objective of this study was to determine the susceptibility of N. lugens to neonicotinoids and other insecticides in major rice production areas in China. RESULTS: Results indicated that substantial variations in the susceptibility to different insecticides existed in N. lugens. Field populations had developed variable resistance levels to neonicotinoids, with a high resistance level to imidacloprid (RR: 135.3–301.3‐fold), a medium resistance level to imidaclothiz (RR: 35–41.2‐fold), a low resistance level to thiamethoxam (up to 9.9‐fold) and no resistance to dinotefuran, nitenpyram and thiacloprid (RR < 3‐fold). Further examinations indicated that a field population had developed medium resistance level to fipronil (up to 10.5‐fold), and some field populations had evolved a low resistance level to buprofezin. In addition, N. lugens had been able to develop 1424‐fold resistance to imidacloprid in the laboratory after the insect was selected with imidacloprid for 26 generations. CONCLUSION: Long‐term use of imidacloprid in a wide range of rice‐growing areas might be associated with high levels of resistance in N. lugens. Therefore, insecticide resistance management strategies must be developed to prevent further increase in resistance. Copyright © 2008 Society of Chemical Industry  相似文献   

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Mesta (Hibiscus sabdariffa) is an important bast fiber crop. In August 2011, there was an outbreak of a phytoplasma-like disease on H. sabdariffa in different villages of the northern coastal mesta-growing region of Andhra Pradesh, India, covering mainly two districts – Srikakulam and Vijayanagaram. The infected plants showed characteristic symptoms such as phyllody and reddening of leaves. PCR with P1/P7 universal primer pair of 16 S rDNA yielded amplicons of 1850 bp from all symptomatic mesta leaf samples similar to samples of brinjal little leaf (phytoplasma positive reference control). However, asymptomatic samples were not amplified. Multiplex nested-PCR showed simultaneous amplification of DNA fragments with phytoplasma specific primers, viz., P1/P7 universal primer pair of 16 S rDNA, nested primer pair R16F2n/R2, uvrB and DegV gene-specific uvrB-degVF/R primer generating amplicons of 1850 bp, 1200 bp and 1023bp, respectively. However, SecY-map gene specific primer SecY-mapF/R was not amplified. The 1023 bp nucleotide sequence of uvrB and DegV gene of the phytoplasma was deposited in the GenBank (NCBI) with the accession no. JX975061. NCBI BLASTn analysis of the 1023 bp products showed that the phytoplasma strain belonged to elm yellows group (16SrV-D). This is the first report that Hibiscus sabdariffa is infected by a phytoplasma and we named it mesta phyllody disease (MPD).  相似文献   

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A field trial was conducted to study the magnitude of quinalphos residues in and/or cauliflower (Brassica oleracea Var Botrytis. The cauliflower crop was sprayed once with quinalphos 25 e.c. at 0.25 and 0.5 kg a.i./ha 104 days after transplanting. The samples of cauliflower drawn at different time intervals were analysed colorimetrically. The initial deposits of quinalphos on cauliflower were found to be 5.79 and 9.52 ppm, an the half life values 1.61 and 2.12 days, respectively, at 0.25 and 0.5 kg a.i./ha. The waiting periods determined were 11 days at the higher and 7 days at the lower dose of quinalphos.  相似文献   

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A 60% azadirachtin-A concentrate has been obtained through repeated precipitation with hexane from a methanolic solution of a 20% concentrate. Azadirachtin-A (90%) has been obtained by medium-pressure liquid chromatography of the 60% concentrate with an RP-18 column and a methanol + water (1 + 1 by volume) solvent system. Catalytic hydrogenation of the 60 and 90% azadirachtin concentrates yielded the corresponding tetrahydroazadirachtin concentrates. Dihydroazadirachtin and tetrahydroazadirachtin formed during the first 5 h of hydrogenation were identified by LC-ESI-MS on the basis of their unique mass fragmentation pattern. The efficacy of tetrahydroazadirachtin concentrates in inhibiting the feeding and growth of Helicoverpa armigera (Hübner) larvae has been compared with that of azadirachtin concentrates. They were in general more active and deterred larvae from feeding at all concentrations. Tetrahydroazadirachtin-A (90%) and azadirachtin-A (90%) with respective IC(50) values of 280 and 390 mg L(-1) were effective as insect growth regulators, while tetrahydroazadirachtin-A (90%) displayed higher antifeedant activity (AI(50) 14 mg L(-1)) against the test insect.  相似文献   

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BACKGROUND: This study focused on determining the minimal effective gamma radiation dose that prevents commodity damage caused by the Indian meal moth Plodia interpunctella (Hübner). The study was also designed to assess the effect of releasing either partially sterilized males alone or both partially sterilized males and females on the reproductive potential of P. interpunctella populations. RESULTS: The dose of radiation required to prevent larval emergence from irradiated eggs was 350 Gy, and the same dose was also required to prevent adult emergence from mature larvae. A dose of 300 Gy was not able to prevent adult emergence from irradiated pupae. The dose at which 100% sterility was achieved in treated females mated to treated males was 300 Gy for the parental generation of irradiated pupae. Fertility of the parental males from irradiated pupae was 48.17% at 300 Gy in treated males crossed with untreated females, but male progeny of irradiated male parents had a residual fertility of 11.06% at the same dose. CONCLUSION: F(1) males from irradiated pupae were more sterile than parental males. To prevent larval emergence from irradiated eggs, a dose of 350 Gy is required. The same dose is required to prevent the larvae from reaching the adult stage.  相似文献   

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Current control of scab and mildew of apple in the UK requires the routine application of fungicides at 7 - 14-day intervals to achieve the blemish-free fruit required by the market. Such practices are generally effective, but with increased public concern about pesticides and rising costs to the grower, they are now less acceptable. The use of disease-warning systems offers scope for optimizing fungicide use by better timing of sprays. Adem? is a PC-based system that warns of the risk of scab, mildew, Nectria fruit rot and canker and fireblight. In a 'key stage' strategy, warnings by Adem? for scab and mildew integrated with practical pest and disease control resulted in similar or better control than a routine programme, with the additional benefit of reduced fungicide inputs and costs even in seasons exceptionally favourable for these diseases. Maximum savings in fungicide use were made by applying sprays curatively in response to scab warnings. However, this approach resulted in increased disease incidence to the crop and scab infection of fruit even in seasons unfavourable for scab attack.  相似文献   

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本文整理了东南亚有分布的寡鬃实蝇属实蝇共48种,分属5亚属,包括其中文名称、学名和地理分布,对无中文名称的32种实蝇给予了中文命名,编制该48种实蝇检索表。并对云南边境诱捕获得的2种寡鬃实蝇进行描述和提供特征图。  相似文献   

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Stable isotopic compositions(δ18O and δD) have been utilized as a useful indicator for evaluating the current and historical climatic and environmental changes. Therefore, it is vital to understand the relationship between the stable isotopic contents in lake water and the variations of lake level, particularly in Lake Qinghai, China. In this study, we analyzed the variations of isotope compositions(δ18O, δD and d-excess) in lake water and precipitation by using the samples that were collected from Lake Qinghai region during the period from 2009 to 2012. The results showed that the average isotopic contents of δ18O and δD in lake water were higher than those in precipitation, which were contrary to the variations of d-excess. The linear regression correlations between δ18O and δD in lake water and precipitation showed that the local evaporative line(LEL) in lake water(δD=5.88δ18O–2.41) deviated significantly from the local meteoric water line(LMWL) in precipitation(δD=8.26δ18O+16.91), indicating that evaporative enrichment had a significant impact on isotopic contents in lake water. Moreover, we also quantified the E/I ratio(evaporation-to-input ratio) in Lake Qinghai based on the lake water isotopic enrichment model derived from the Rayleigh equation. The changes of E/I ratios(ranging from 0.29 to 0.36 between 2009 and 2012) clearly revealed the shifts of lake levels in Lake Qinghai in recent years. The average E/I ratio of 0.40 reflected that water budget in Lake Qinghai was positive, and consistent with the rising lake levels and the increasing lake areas in many lakes of the Tibetan Plateau. These findings provide some evidences for studying the hydrological balance or water budget by using δ18O values of lake sedimentary materials and contribute to the reconstruction of paleolake water level and paleoclimate from an isotopic enrichment model in Lake Qinghai.  相似文献   

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