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2019年缅甸草地贪夜蛾发生情况考察报告 总被引：4，自引：0，他引：4
缅甸是我国草地贪夜蛾的重要境外虫源区, 为了掌握草地贪夜蛾在缅甸的发生与防控情况, 2019年5月19-25日, 云南省农业科学院与缅甸农业研究司专家联合对缅甸南部、中部、中北部和东部草地贪夜蛾开展了实地调查。结果表明: 缅甸全境均有草地贪夜蛾发生, 为害严重, 田间多种虫态并存。其中, 南部玉米大部分已经收获, 虫株率62.50%~97.50%; 中部区域种植少量的商品甜玉米, 防治到位, 虫株率6.00%~7.50%; 中北部曼德勒敏建玉米种植面积最大, 达8 000 hm2, 80%的地块已成熟收获, 处于吐丝-乳熟期的田块虫株率达100%, 受害严重; 东部掸邦虫株率59%, 虫口密度2.60头/株。玉米是缅甸第二大种植作物, 全年玉米种植面积达47万~52万hm2, 其中与我国云南接壤的东部掸邦是主要种植区。到5月前因无有效降雨, 全境玉米尚未大面积种植, 仅有零星种植, 随着雨季的来临, 玉米种植面积将全面增加, 草地贪夜蛾种群数量也将随之增加。因此, 加强与缅甸相关部门合作, 密切掌握缅甸玉米种植及草地贪夜蛾的发生与防控情况, 对我国草地贪夜蛾的监测预警及防控有重要的参考价值。 相似文献
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云南草地贪夜蛾冬春季虫源分布及其主要影响因素分析 总被引：1，自引：0，他引：1
云南是我国草地贪夜蛾Spodoptera frugiperda主要降落区、周年繁殖区和北迁南回的重要通道。本研究基于室内生物学测定和全省气象数据, 并通过田间实地调查, 对冬春季虫源分布区及其主要影响因素进行了分析。结果表明:1)云南全省129个县/区/市中有45个县/区/市为草地贪夜蛾的周年繁殖适宜区, 有64个县/区/市为幼虫冬春季发生区。周年繁殖适宜区和幼虫冬春季发生区主要分布在25°N以南的西部、西南部、南部和东南部区大部区域, 以及西部怒江和北部金沙江沿岸部分地区。2)云南东西部草地贪夜蛾的发生程度和种群数量存在明显差异, 具有典型的区域特点:西部至南部普遍发生, 种群数量高, 为害严重, 有虫田率超过90%, 平均受害株率为30%~59%, 平均百株虫量为20~47头; 东南局部区域发生轻, 平均被害株率13.01%, 百株虫量12头; 中部及以北地区除河谷热区外, 冬春季未见有草地贪夜蛾为害。调查结果与虫源分布区预测结果重合度较高。3)玉米种植分布和生育期对草地贪夜蛾的发生有直接影响, 同时, 用药水平及种植模式与草地贪夜蛾的发生程度关系密切。研究结果对草地贪夜蛾种群监测与预警有指导作用。 相似文献
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2019年我国草地贪夜蛾扩散为害规律观测 总被引：39，自引：0，他引：39
草地贪夜蛾Spodoptera frugiperda(J.E.Smith)侵入我国后呈现快速蔓延为害态势,对我国玉米安全生产造成较大威胁。本文通过全国范围的系统监测,总结了2019年我国草地贪夜蛾侵入扩散区域、为害作物种类、发生面积、发生时间、虫口密度和为害情况。监测结果显示,玉米是我国草地贪夜蛾为害最重的作物。草地贪夜蛾在长江以南地区普遍发生,发生区域由南至北逐步扩散,虫口密度由南至北逐步递减,发生时间西部早于东部,虫口密度西部大于东部。缅甸是我国2019年重要的虫源地,未来应加强对缅甸、泰国和越南等东南亚国家虫源的监测;我国热带和南亚热带存在冬繁区,应尽快摸清其区域和面积;分析了草地贪夜蛾在我国可能发生的代次,提出南方春玉米的种植对草地贪夜蛾起到诱集作用,可延缓或减轻其北迁的时间和虫量,因此,应重视我国玉米品种和种植方式的合理布局,实现对草地贪夜蛾的长期有效治理。 相似文献
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我国草地贪夜蛾的防控对策与建议 总被引：11，自引：0，他引：11
草地贪夜蛾Spodoptera frugiperda(J.E.Smith)是世界性重大农业害虫,该虫自2019年1月入侵我国云南省到5月下旬,在不到5个月的时间里就已经入侵了长江流域及其以南的15个省(市、自治区)。预计6月和7月将到达我国的玉米主产区黄淮海夏玉米区和北方春玉米区,受威胁玉米面积1 300多万hm 2,将严重威胁我国的玉米生产安全。我国玉米的种植布局随季节和纬度变化从南至北递次推移,时间和空间上互补,为草地贪夜蛾提供了丰富的食物资源,为其种群区域性迁移和周年繁殖为害提供了良好的自然条件。为做好草地贪夜蛾的防控工作,及时控制其为害,本文在总结国内外防控草地贪夜蛾经验教训的基础上,初步提出了我国草地贪夜蛾的防控对策。 相似文献
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The Illinois soybean crop was monitored in 1965, 1966, 1967, 1971, and 1974 for dieldrin residues resulting from aldrin applied to corn in the years before soybean cultivation. Residue levels of dieldrin in soybeans increased between 1965 and 1974. The percent of fields which had soybeans with a dieldrin level above 0.03 ppm increased between 1965 and 1974. Dieldrin residue levels in soybeans grown in Illinois are expected to decline now that the use of aldrin has diminished and will soon cease. No significant correlation was evident between the dieldrin levels in soybeans and the area of the State where they had grown, the date of planting, or the variety. 相似文献
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Dr Ir M. Oostenbrink Ir H. den Ouden 《European journal of plant pathology / European Foundation for Plant Pathology》1953,59(3):95-100
Summary
Heterodera cruciferae is found in the Netherlands in five different locations, living on cabbage, rape and rapeseed, whereas beets are not attacked. ThisHeterodera is distinguished from nearly all otherHeterodera's known in Europe by its small, red brown, roundish lemon-shaped cysts and its short, thick larvae(Fig. 1, 2, 3, 5). The only exception isHeterodera humuli, which has however a thinner cyst wall of a lighter colour with a conspicuous, coarse, irregular punctation and larva stylets with distinctly forward-pointing knobs (Fig. 7, 8). The males are redescribed; they have 5–7 lip annules and three teeth on each spiculum tip (Fig. 4). Population density and type of damage with culture of rape seem to be about the same as with beet sickness caused byH. schachtii (Fig. 6). In the most important cabbage areaH. schachtii plays a more important role thanH. cruciferae. With both eelworms, an advisory service based on soil sample examinations would probably be useful for the culture of cruciferous crops. 相似文献
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Organochlorinated compounds were monitored in oldsquaws (Clangula hyemalis) and their food from Lake Michigan between October and May, 1969-72; in adult oldsquaws, eggs, young, and food from northwest Hudson Bay in 1971; and in oldquaws from five wintering areas other than Lake Michigan in 1971-73. Analyses were conducted on 300 carcasses, 14 wings, 29 gullet samples, and 11 clutches. Average residues in carcasses from Lake Michigan ranged from 4 to 107 ppm PCBs, 2 to 42 ppm DDE, and less than 0.1 to 0.7 ppm endrin. Differences in DDE levels occurred between several sex and age classes during December on Lake Michigan; these differences were not apparent in the spring. Increases in DDE and PCB residues for oldsquaws occurred on Lake Michigan between December and May. DDE residues in the wing and carcass were significantly correlated. Residues were relatively low in oldsquaw foods from Lake Michigan; concentration factors between the food and the ducks varied between 1X and 22X, depending on the date and compound. Organochlorinated residues were lower in Arctic than in Lake Michigan food samples. DDE in paired male and female oldsquaws was highly correlated, as was DDE in females and clutches. Eggshell thickness had declined 4.5% compared with eggs collected before 1947. Residues were higher in oldsquaws wintering on the Great Lakes and lowest in oldsquaws from coastal areas. 相似文献
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Mercury, arsenic, and cadmium in fish, water, and sediment of American Falls Reservoir, Idaho, 1974.
Mercury and cadmium were found in fish, water, and sediment of American Falls Reservoir (AFR), Idaho. Mercury and cadmium levels in some fish exceeded human health standards set by the Food and Drug Administration, U.S. Department of Health, Education and Welfare, and the World Health Organization. Analyses performed on the flesh of rainbow trout showed mercury residues of up to 1.20 mg/kg, which were higher than residues previously reported in trout collected in 1970 and 1971 from AFR. Cadmium residue levels were as high as 0.80 mg/kg. Although arsenic was found in reservoir sediment at levels of 1.36-2.40 mg/kg, it was not detected in fish. 相似文献
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W. D. Smilde M. van Nes H. D. Frinking 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(7):687-695
Cardinal temperatures for mycelial growth ofPhytophthora porri on corn-meal agar were <5 (minimum), 15–20 (optimum) and just above 25 °C (maximum). The number of infections after zoospore inoculation of young leaf plants was relatively low at supra-optimal temperatures, but was not affected by sub-optimal temperatures. Even at 0 °C plants were infected. The incubation periods needed for symptom formation were 36–57 d at 0 °C, 13–18 d at 5 °C, and 4–11 d at > 11 °C, and were fitted to temperature between 0 and 24 °C with a hyperbolical model (1/p=0.00812*T+0.0243). Oospore germination, reported for the first time forP. porri, was strongly reduced after 5 h at 45 °C, and totally absent after 5 h at 55 °C. Soil solarization for six weeks during an exceptionally warm period in May–June 1992 in The Netherlands raised the soil temperature at 5 cm depth for 17 h above 45 °C, but did not reduce the initial level of disease in August significantly. 相似文献
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本文首次报道新疆维吾尔自治区乌鲁木齐周围地区的盘星藻属５种,４变种,其中４株,４变种为新疆新记录,这些结果是对１９９１年７月和１９９５年４－６月所采集的８７号标本鉴定后获得的。 相似文献
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绝大多数啮齿动物种类为植食性的小型哺乳动物，其生物学特性导致了鼠类危害的复杂性。当前，面对日益提高的生态安全需求，粮食安全、人民健康和生物安全以及生态安全对鼠害控制需求的差异造成了中国鼠害防控策略制定及实施的困扰。尤其在草原地区，如何在应急性灭杀和长效缓控之间找到一个平衡点是目前鼠害防控面临的一个巨大挑战。针对这些矛盾和挑战，该文分析了我国鼠害监测防控的现状、主要瓶颈与短板，并从技术层面提出“精准监测指导精准防控”可能会是解决这些矛盾的有效途径，是在有效控制鼠害暴发对粮食生产和人民健康安全威胁的前提下，推进生态保护和修复的有效途径。 相似文献