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1.
松突圆蚧虫口数量与危害程度的关系   总被引:1,自引:1,他引:0  
通过大面积的野外调查研究。结果表明:松突圆蚧每针束平均虫口数量(a)、针束最高虫口数量(b)、有虫针束率(c)和危害程度(d)4个指标之间均呈显著或极显著正相关。在野外虫口数量调查中可用针束最高虫口数量替代每针束平均虫口数量指标,以有虫针束率指标作为每针束平均虫口数量和针束最高虫口数量的有效参考指标。在危害程度的调查中,可用有虫针束率作为替代指标,以针束最高虫口数量和每针束平均虫口数量分别作为第1和第2参考指标。3个虫口数量指标中以有虫针束率对危害程度的直接作用最大,其次是针束最高虫口数量,每针束平均虫口数量最低。在间接作用中,针束最高虫口数量通过有虫针束率对危害程度的影响最大,每针束平均虫口数量通过有虫针束率的间接影响较大。  相似文献   

2.
为了寻找重要指标, 从而研究松突圆蚧Hemiberlesia pitysophila Takagi对不同马尾松Pinus massoniana品系的危害程度, 揭示昆虫数量指标所反映的直接和间接危害程度。选取一块林场试验地, 通过虫口密度等6个指标进行调查, 采用单向通径分析法分析。结果表明:直接影响最大正向指标为虫口密度和有虫针束率, 间接影响最大负向指标为有虫针束率。综合起来, 反映危害程度加大的重要指标依次为:虫口密度、有虫株率、定殖虫口数量、1龄若虫存活率、2龄若虫存活率、有虫针束率。28个马尾松品系可分为4类, 其中最受危害的是390和439, 危害最小的是469和458。分析结果之间基本一致, 与实际基本相符。因此, 本文结果对选取考察指标及其抗虫品系的选育提供了重要的参考价值。单向通径分析法在理论上有一定的合理性和创新性, 在实际上是可行的, 值得研究和推广。  相似文献   

3.
5种杀虫剂对滇东白背飞虱种群的毒性及其田间药效   总被引:1,自引:0,他引:1       下载免费PDF全文
【目的】为持续有效防控白背飞虱,研究云南东部白背飞虱种群对常用5种杀虫剂的敏感性及药剂的田间防治效果。【方法】采用室内稻茎浸渍法测定白背飞虱种群对5种杀虫剂的敏感性,同期通过田间小区试验评价5种杀虫剂对白背飞虱种群的防治效果。【结果】与敏感种群比较,噻虫嗪、噻嗪酮、吡虫啉、吡蚜酮和毒死蜱对滇东白背飞虱种群的LC_(50)分别为0.208、0.459、0.608、3.108、1.256 mg·L~(-1),抗性倍数分别为2.2、10.4、5.6、6.5、5.3倍;白背飞虱对噻虫嗪无抗性,对吡虫啉、吡蚜酮和毒死蜱为低水平抗性,对噻嗪酮为中等水平抗性;5种杀虫剂药后1、5和10 d对白背飞虱种群的田间防控效果均有显著差异。除了吡蚜酮外,其他药剂的防效均在80%以上,其中以吡虫啉和噻嗪酮的持续期较长,药后10 d仍在90%以上;噻虫嗪和吡虫啉药后1和5 d的防效达90%以上;吡蚜酮药效在供试药剂中防效最低,在64.88%~77.82%之间。【结论】滇东师宗白背飞虱种群对噻嗪酮为中等水平抗性,对吡虫啉、吡蚜酮和毒死蜱均为低水平抗性,对噻虫嗪无抗性,田间防控效果以吡虫啉和噻嗪酮为最好。建议滇东稻区可以使用吡虫啉和噻嗪酮药剂防控白背飞虱,注意控制吡蚜酮的使用次数与用量。  相似文献   

4.
【目的】日本蜡蚧Ceroplastes japonicus Green是柿树(Diospyros kaki L.f.)上的重要害虫,该论文目的是明确柿日本蜡蚧Persimmon ceroplastes japonicus在云南省玉溪市的发生规律,筛选出有效药剂。【方法】依据本地的物候规律系统调查日本蜡蚧的发生情况,采用随机区组设计筛选有效药剂。【结果】日本蜡蚧在云南省玉溪市1年发生1代,以受精雌成虫在1~2年生枝条上越冬,翌年2月初,气温稳定在6℃以上开始发育,3月上旬开始产卵,3月下旬孵化,5月上旬—6月上旬为孵化盛期,7月上旬雌虫陆续由叶转到枝上固着危害,至秋后开始进入越冬期。用48%毒死蜱(480g/L EC)5 000倍液、24%螺虫乙酯(240g/L SL)2 500倍液、2.5%高效氯氰菊酯(EC)2 500倍液、40%杀扑磷(EC)1 000倍液、25%噻虫嗪(WG)8 000倍液、20%阿维菌素·毒死蜱(ME)(阿维菌素0.2%和毒死蜱19.8%)2 000倍液和90%敌百虫原药1 000倍液,喷雾时添加2 500倍液有机硅喷雾助剂。田间防治试验表明:施药后5 d,2.5%高效氯氰菊酯和40%杀扑磷防效分别为93.7%和91.9%,均显著高于其余5种药剂的防效;施药后10 d,24%螺虫乙酯和20%阿维菌素·毒死蜱的防效分别为96.2%和92.9%,均显著高于2.5%高效氯氰菊酯、40%杀扑磷和90%敌百虫原药的防效;施药后20 d 48%毒死蜱、24%螺虫乙酯、25%噻虫嗪和20%阿维菌素·毒死蜱的防效分别为85.2%、96.6%、83.3%和93.7%,均显著高于2.5%高效氯氰菊酯、40%杀扑磷和90%敌百虫原药的防效。【结论】日本蜡蚧在云南省玉溪市一年发生1代。高效氯氰菊酯和杀扑磷具有较好的速效性,螺虫乙酯和阿维菌素·毒死蜱混剂持效性较好。  相似文献   

5.
松突圆蚧空间分布型的研究   总被引:8,自引:0,他引:8  
应用聚集度指标和回归分析,对松突圆蚧空间分布型进行测定,结果表明:松突圆蚧的若虫在松林中呈聚集分布,聚集度随虫口密度增大而增强;而成虫在松林中呈均匀分布,从而确定出不同种群密度下最适抽样数。通过林间调查和数理统计分析,结果表明:松突圆蚧在松树枝条的东、南、西、北不同方位,以及松树树冠的上、中、下不同层次和幼林、中龄林、成林不同树龄的松林之间的虫口数量差异不显;但在郁闭度不同的松林中虫口数量存在着显差异。  相似文献   

6.
几类杀虫剂对灰飞虱的相对毒力及田间种群的抗药性现状   总被引:8,自引:0,他引:8  
采用浸苗法测定了6类11种杀虫剂对灰飞虱Laodelphax striatellus (Fallén)3龄若虫的毒力,并分析比较了江苏句容、通州、楚州、大丰、南京和苏州以及安徽庐江等7地灰飞虱种群对10种杀虫剂的抗药性水平。对云南种群而言,在所测杀虫剂中,以乙酰甲胺磷为标准药剂,氟虫腈的相对毒力最高;噻嗪酮、阿维菌素和噻虫嗪次之;高效氯氰菊酯、IPP(硝基亚甲基类化合物)、毒死蜱、敌敌畏和三唑磷间毒力处于同一数量级,低于阿维菌素等杀虫剂;吡虫啉的相对毒力最低。与云南种群相比,2007年采自苏、皖7个不同地区的灰飞虱种群对噻嗪酮产生了极高水平的抗性,其抗性倍数均超过200倍;对高效氯氰菊酯产生了中高水平的抗性,其抗性倍数为7.8~108.8;安徽庐江灰飞虱种群对三唑磷产生了7.7倍的抗性,对毒死蜱产生了12.0倍的抗性,江苏楚州、南京、大丰和句容灰飞虱种群对毒死蜱产生了5.7~12.6倍的抗性; 所有灰飞虱种群对敌敌畏仍然敏感,对氟虫腈、阿维菌素和新烟碱类杀虫剂吡虫啉、噻虫嗪和IPP等也比较敏感。  相似文献   

7.
本文旨在找出重要的指标,从而揭示松突圆蚧Hemiberlesia pitysophila Takagi的数量变化与环境因素变化、马尾松Pinus massoniana所受危害程度间相互存在的重要关系。于福建省松突圆蚧发生区选取了4块调查标准样地,对松突圆蚧的6个数量指标和6个环境因子及其对马尾松受危害程度进行了调查,并对调查结果进行了综合相关系数分析。结果表明,环境因子与松突圆蚧数量指标之间存在显著的综合负相关,全N、全P、温度、雌成虫虫口密度、雄成虫虫口密度、2龄若虫虫口密度都是重要指标。松突圆蚧数量指标与马尾松受危害程度之间存在显著的综合正向相关性,环境因子与马尾松受危害程度之间不存在显著的综合相关性。综合相关系数分析所得的各种结果之间非常协调一致,与实际也基本相符。结论认为:环境因子对松突圆蚧数量变化有重要影响,松突圆蚧数量变化对马尾松危害程度有重要影响,而环境因子对马尾松危害程度影响不大;综合相关系数分析法是科学合理的,有一定的创新性和实用性,值得推广研究。  相似文献   

8.
褐飞虱和白背飞虱对几类杀虫剂的敏感性   总被引:8,自引:0,他引:8  
为了科学用药和抗性治理提供理论基础, 采用稻茎浸渍法测定了2008年7月采自浙江省杭州市和宁波市褐飞虱 Nilaparvata lugens (Stål)种群对7种杀虫剂的抗药性及褐飞虱和白背飞虱Sogatella furcifera (Horváth)种群对16种杀虫剂的敏感性。褐飞虱抗药性测定结果表明, 与相对敏感品系相比, 杭州种群和宁波种群对吡虫啉的抗性倍数分别为479.0倍和366.1倍; 对氯噻啉的抗性倍数分别为81.1倍和50.9倍; 对噻虫嗪的抗性倍数分别为10.3倍和9.4倍; 对噻嗪酮和氟虫腈分别产生了5.0~8.6倍和15.8~17.0倍的抗药性; 对烯啶虫胺和啶虫脒的抗性倍数在3倍以下。两种稻飞虱对杀虫剂的敏感性测定结果表明: 噻虫嗪、噻嗪酮、烯啶虫胺和毒死蜱对褐飞虱和白背飞虱种群都具有较高的室内毒力。当田间褐飞虱和白背飞虱混合发生时, 可选用噻虫嗪、噻嗪酮、烯啶虫胺和毒死蜱进行防治, 不宜使用吡虫啉、氯噻啉和氟虫腈防治。  相似文献   

9.
为筛选出适用于云南热带雨林生态区的红火蚁Solenopsis invicta Buren防治药剂,通过7种杀虫剂对红火蚁蚁巢田间灭除效果试验测定。结果表明,20%多杀霉素悬浮剂(SC)、30%螺虫·噻虫嗪悬浮剂(SC)、70%吡虫啉可湿性粉剂(WP)、10%溴虫氟苯双酰胺悬浮剂(SC)和1%联苯·噻虫嗪颗粒剂(GR)对红火蚁蚁巢处理效果较好,药后1 d和10 d虫口减退率分别在95%和90%以上。其中10%溴虫氟苯双酰胺SC和1%联苯·噻虫嗪GR可作为红火蚁巢点处置的首选药剂;0.05%茚虫威饵剂(EB)速效性差,但药后10 d虫口减退率上升到86.8%。1.8%阿维菌素乳油(EC)药后1 d和10 d虫口减退率分别为89.3%和81%。这2种药剂可与前5种药剂交替使用。  相似文献   

10.
三种药剂及其复配剂对松突圆蚧的毒力测定   总被引:10,自引:1,他引:9  
本以机油乳油、毒死蜱及喹硫磷对松突圆蚧1龄若虫进行室内毒力测定,结果表明各药剂对松突圆蚧均有一定的毒力,其中喹硫磷的毒力明显大于其它两种药剂的毒力,但喹硫磷与毒死蜱及机油复配没有增效作用,而机油乳油与毒死蜱以13:10混配,增效作用明显,共毒系数达到405.41.  相似文献   

11.
Abstract  Chemical control trials against fig longicorn, Acalolepta vastator , were conducted on grapes in New South Wales between 1989 and 1994 using materials, some registered and others unregistered, for use in grapevines. Emerging adults and newly hatched larvae were exposed to direct and residual contact in a seasonal spraying strategy. Azinphos-methyl, chlorpyrifos and methidathion initially demonstrated efficacy, but later trials produced variable results with the first two insecticides. Azinphos-methyl gave superior residual adult control to chlorpyrifos. An urgent need for field control resulted in azinphos-methyl, chlorpyrifos and methidathion being recommended against A. vastator . Initial industry adoption resulted in an immediate reduction in the pest population, but a subsequent pest resurgence stimulated further study into more effective chemicals. In a trial of some new chemicals, imidacloprid and λ-cyhalothrin gave excellent control. A new spraying strategy comprising concentrated λ-cyhalothrin applied twice, the first early in the season and the second post-vintage gave excellent control. Difficulties with seasonal spraying provide encouragement for further development of this approach.  相似文献   

12.
【目的】明确25%吡蚜酮SC、3%甲氨基阿维菌素苯甲酸盐ME、25%噻虫嗪WG、14%氯虫·高氯氟ZC、15%高氯·毒死蜱EC、2.5%高效氯氟氰菊酯EW和40%毒死蜱EC 7种杀虫剂对小麦吸浆虫和蚜虫的防治效果,为科学、合理用药防治小麦害虫提供参考。【方法】采用喷雾法和剥穗调查法,研究它们对小麦吸浆虫成虫和麦蚜的防效,及防后对小麦吸浆虫幼虫危害损失的影响。【结果】参试药剂药后1 d对小麦吸浆虫成虫防效均高于90%,药后3~5 d防效为84.81%~93.93%,防后挽回损失76%以上;对麦蚜药后1、3、5 d防效分别高于75%、80%和85%。在供试的7种药剂中,15%高氯·毒死蜱EC药后3~5 d对两种害虫防效、挽回吸浆虫危害均超过90%,应用效果最好;其次为25%噻虫嗪WG和40%毒死蜱EC,药后3~5 d对吸浆虫防效高于90%、对麦蚜防效分别高于86%和90%,挽回吸浆虫危害损失88%以上。【结论】供试药剂对小麦吸浆虫和麦蚜防效存在显著差异,15%高氯·毒死蜱EC对两种害虫防治效果最好。  相似文献   

13.
新烟碱类杀虫剂拌种对麦蚜田间防效及药剂残留动态分析   总被引:1,自引:0,他引:1  
为了分析两代新烟碱类杀虫剂吡虫啉和噻虫嗪拌种对麦蚜的防治效果的差异以及2种药剂在小麦叶片内的残留动态,采用吡虫啉和噻虫嗪有效剂量0.5、1.0、2.0和4.0g/kg小麦种子在播种前进行1次性拌种处理,随后调查了不同处理下田间麦蚜的种群密度,并对不同时期小麦叶片内的药剂残留进行了监测。结果表明:吡虫啉有效剂量2.0和4.0g/kg,噻虫嗪有效剂量1.0、2.0和4.0g/kg小麦种子播前拌种能有效的降低田间麦蚜的种群数量。在4月10日前,吡虫啉在小麦叶片内的含量明显高于噻虫嗪,4月28日后两者差异不明显。与吡虫啉相比,噻虫嗪对麦蚜具有更高的生物活性和控制效果。  相似文献   

14.
In this study, we formulated pesticides from 12 products, namely machine oil EC, imidacloprid WP, thiamethoxam WP, acetamiprid WP, methidathion EC, acequinocyl WP, clothianidin WP, deltamethrin EC, mancozeb WP, benomyl WP, difenoconazole WP, and bitertanol WP. These 12 pesticides were selected to determine their toxicity to green lacewing, Chrysoperla nipponensis, at the maximum field recommended dosage under laboratory conditions. Machine oil EC had extremely detrimental effects on eggs of C. nipponensis, resulting in 99% mortality (categorized as Class IV) when eggs were treated with machine oil EC by dipping. Mean larval corrected mortalities (%) for methidathion EC and deltamethrin EC were 62.5% (categorized as Class II) and 87.5% (categorized as Class III) respectively, when larvae were topically treated. As a result of dipping treatments of pupae with pesticides, machine oil EC and thiamethoxam WP were classified as slightly harmful (categorized as Class II). Methidathion EC showed high toxicity, resulting in a total effect index rate 100% (categorized as Class IV). Taxonomical notes of the genus Chrysoperla and C. nipponensis are reviewed here.  相似文献   

15.
Sminthurus viridis (lucerne flea) is a major crop and pasture pest throughout southern regions of Australia that experience a Mediterranean type climate. It is particularly problematic at the establishment phase, and chemicals are currently the main option available to farmers for their control. Few studies have assessed the currently registered pesticides for the control of S. viridis , and rates of application are generally similar to the frequently co-occurring red-legged earth mite, Halotydeus destructor , despite few comparisons between species for their susceptibility being made. Here, we examine the response of S. viridis to six pesticides (α-cypermethrin, bifenthrin, omethoate, methidathion, chlorpyrifos and phosmet) and then directly compare them with H. destructor . S. viridis displayed similar dose–response curves for bifenthrin, omethoate, chlorpyrifos and phosmet. It had greater sensitivity to methidathion and greater tolerance to α-cypermethrin. S. viridis was found to be significantly more tolerant than H. destructor to all pesticides tested, with the exception of chlorpyrifos. This indicates that rates of application for control of S. viridis should be greater than H. destructor and that the organophosphates are likely to provide the most effective control of this pest.  相似文献   

16.
The effect of insecticides on oviposition of Tiphia vernalis Rohwer and subsequent survival of parasitoid progeny to the cocoon stage was determined in the laboratory by using larval Japanese beetle, Popillia japonica Newman, as the host. Insecticides tested were imidacloprid, thiamethoxam, halofenozide, chlorpyrifos, and carbaryl at labeled rates. Female T. vernalis were allowed 2 d to parasitize P. japonica larvae after the parasitoids had received a 4-d exposure to insecticide-treated soil. Another group of female T. vernalis were allowed 2 d to parasitize P. japonica larvae that had been exposed to insecticide-treated soil for 3-4 d. Percentage of parasitism of P. japonica larvae in these trials after exposure of adult parasitoids to carbaryl, chlorpyrifos, halofenozide, or imidacloprid-treated soil (23.3-50.0%) or adult parasitoids to chlorpyrifos, halofenozide, or imidacloprid-treated grubs (33.0-56.7%) was not negatively affected relative to the control treatment (21.7-54.2%). A third group of adult T. vernalis and P. japonica larvae were simultaneously exposed to chlorpyrifos or carbaryl treatments. Percentage parasitism in these trials was lower for T. vernalis adults exposed to the chlorpyrifos and carbaryl (15.0-25.0%) relative to the control (57.5-62.5%) with the exception of one trial with carbaryl (40.0%). However, exposure of the parasitoid and P. japonica to chlorpyrifos 0.5X, carbaryl 0.5X, imidacloprid, halofenozide, or thiamethoxam in several trials resulted in parasitism that was equivalent or greater than (45.0-80.0%) the untreated control (57.5-62.5%). Japanese beetle larval mortality in these trials was greater in the insecticide and parasitoid combination (97.5-100.0%) than with insecticides alone (45.0-100.0%). Percentage of survival of T. vernalis progeny to the cocoon stage was not negatively affected by a 4-d adult parasitoid exposure to carbaryl and chlorpyrifos treated soil (11.7-16.7% versus 18.3% control) or a 2-d exposure to P. japonica-treated larvae (16.7-18.3% versus 28.3% control). However, simultaneous exposure of T. vernalis progeny and P. japonica larvae to chlorpyrifos- and carbaryl-treated soil resulted in no parasitoids surviving to the cocoon stage. Between neonicotinoids, thiamethoxam had more adverse impact on percentage parasitism (52.5%) and survival to the cocoon stage (10.0%) than imidacloprid (80.0 and 32.5%, respectively). Results of this study indicate soil incorporation of imidacloprid and halofenozide had minimal effect on the number of P. japonica larvae parasitized by T. vernalis or survival of T. vernalis progeny to the cocoon stage; therefore, they are more suitable for use with T. vernalis. In contrast, chlorpyrifos, carbaryl, and thiamethoxam lowered the number of T. vernalis progeny surviving to the cocoon stage, and carbaryl and chlorpyrifos reduced the number of P. japonica larvae parasitized. The soil incorporation of insecticides is discussed as one explanation for the minimal effects of some insecticides on T. vernalis.  相似文献   

17.
The susceptibility of Stethorus punctum picipes (Casey) and Harmonia axyridis Pallas larvae to pesticides used or with potential for use in Washington hops, was examined in laboratory bioassays. All pesticides tested except the miticide, hexythiazox, the insecticides, chlorpyrifos and pirimicarb, and the fungicide, mycobutanil, produced 100% mortality in S. punctum picipes at concentrations equivalent to field rates. The insecticides, pirimicarb, endosulfan, and thiamethoxam were least toxic to H. axyridis. Bifenthrin, diazinon, dimethoate, methomyl, carbaryl, malathion, phosmet, imidacloprid, and chlorpyrifos were highly toxic. The miticides, abamectin and fenpyroximate were highly toxic, milbemectin was moderately toxic but all other miticides tested were non-toxic. All fungicides had low toxicity. Selection and use of pesticides compatible with natural enemies and conservation biological control in Washington hop production is discussed.  相似文献   

18.
The brown Planthopper (BPH), Nilaparvata lugens is a major pest of rice production in tropical Asia. The appearance of insecticide resistance challenges the control of BPH in field. The development of new insecticide is expensive and time-consuming. Thus, the precise and proper use of existing compounds becomes an important issue in resistance management of this pest. In this study, five commercial insecticides of BPH (permethrin, chlorpyrifos, imidacloprid, clothianidin and thiamethoxam) were tested to explore the toxicity of the binary mixture between different kinds of insecticides. In all combinations of mixture, the mixtures of permethrin and chlorpyrifos displays synergistic effect at three different mixture ratios (1:1, 1:10 and 10:1). The strongest synergism observed in permethrin/ chlorpyrifos mixtures at 1:1 ratio (Combination index, CI = 0.39). Addition of enzyme inhibitor followed by detoxification enzyme activity assays suggested that the mechanism of synergistic effect of permethrin/chlorpyrifos mixture may result from inhibition of the cytochrome P450 monooxygenase and esterase activity. This inference can be supported through two lines of evidence. One is decrease of toxicity when permethrin/chlorpyrifos mixture in a 1:1 ratio plus triphenyl phosphate (TPP) or piperonyl butoxide (PBO), but increase of toxicity when permethrin/chlorpyrifos mixture in a 10:1 ratio plus TPP or PBO. Another is exposure of the 3rd instar nymphs to permethrin/chlorpyrifos mixture after 72 h also significantly decreased both cytochrome P450 monooxygenases and esterase activity. Further field trail showed the mixture of 50 ppm permethrin +50 ppm chlorpyrifos increased the field control efficiency significantly rather than permethrin alone or chlorpyrifos alone. Our study indicated that the mixture of permethrin and chlorpyrifos in a 1:1 ratio might be an effective method for the control of BPH in paddy field.  相似文献   

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