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1.
高孢子含量Bt制剂对桃小食心虫毒效的初步试验   总被引:1,自引:0,他引:1  
本报道国产高孢子含量Bt(1.6×10^4IU)可湿性粉剂对桃小食心虫初孵幼虫的室内和田间药效,及其与低浓度化学农药混用的试验结果。室内实验表明,在苹果上分别喷酒高含量Bt可湿粉1000和2000倍液后接虫,第3天幼虫蛀果率均为零;喷酒2.5%溴氰菊酯(3个供试浓度)的结果与之相同,亦无1头幼虫蛀入果内。但是,高含量Bt可湿粉2000倍液在田间的残效期较短,施药后第3天和第6天在苹果上接虫,死亡  相似文献   

2.
东方粉蝶是十字花科蔬菜上的重要害虫,在铜鼓县一年发生6—8代,以蛹越冬,卵期3—5天。幼虫期,第1代16—18天,第2~6代11—13天,第7~8代18—20天,11月为25天。蛹期5~10月中旬为7~10天,10月底~11月初为12~18天,越冬蛹128~174天,成虫寿命,雄为3—4天,雌为7—8天,产卵量150粒左右。文中对该虫的形态作了描述和绘图。防治时,给合人工捕采幼虫和卵粒,田间施药可用2.5%敌杀死剂2500—3000倍液、90%敌百虫1000倍液、50%马拉硫磷或敌敌畏800—1000倍液,防治效果很好。  相似文献   

3.
梨星毛虫是我国梨和苹果产区的重要害.虫之一,60年代以前主要以DDT控制。有机氯杀虫剂禁用后,此虫又有回升,在粗放管理的果园损失尤为严重。作者于1983—1985年在河北省廊坊地区筛选杀卵与防治出蛰幼虫的药剂,近年已在生产中推广。 一、室内药效试验 供试药剂为40%乐果乳油(1000、2000倍)、50%对硫磷乳油(1500、3000倍)、50%地亚农乳油(1000、2000倍)、50%敌敌畏乳油(800、1600倍)、50%辛硫磷乳油(1000、2000倍)、50%杀螟松乳油(1000、2000倍)、20%杀灭菊酯乳油(2000、4000倍)、2.5%溴氰菊酯乳油(2500、4500倍)。 (一)杀卵试验 田间采集梨星毛虫卵块,按以上药剂和  相似文献   

4.
铜色花椒跳甲生物学特性及其防治研究   总被引:7,自引:0,他引:7  
铜色花椒跳甲(Podagricomela cuprea Waog)是近年来在陇南山区首次发现危害花椒的新害虫。据室内饲养和田间定点观察,该虫1年发生1代,以成虫越冬,翌年4月中旬出蛰活动。4月底至5月中旬,幼虫蛀食花椒聚伞状花序梗、羽状复叶柄和幼嫩果实,致使花椒减产,甚至绝收。田间药剂防治试验表明,应用杀灭菊酯4000—5000倍液,水胺硫磷、杀螟松等1000—1500倍液,于4月下旬花椒现蕾期喷洒,保叶效果90%左右,保花效果达95%以上,大田防治示范证明,增产效果好,经济效益显著。  相似文献   

5.
转Bt基因玉米对棉铃虫的抗性评价   总被引:2,自引:2,他引:2  
棉铃虫Helicoverpa armigem(Htlbner)是常年危害玉米的重要害虫。转Bt基因抗虫玉米为害虫的防治提供了新的途径。采用室内离体生物测定方法测定了孟山都转Bt基因抗虫玉米Yield—Gard不同组织对棉铃虫初孵幼虫的杀虫活性以及田间人工接虫抗性鉴定。Bt玉米花丝、苞叶和幼嫩雌穗对棉铃虫具有较高的杀虫活性,取食Bt玉米花丝和幼嫩雌穗(籽粒和穗轴)的棉铃虫初孵幼虫不能存活和完成幼虫期发育,而对照分别有51.0%和22.0%个体完成幼虫期发育。以Bt玉米雌穗苞叶饲养棉铃虫初孵幼虫,5天后幼虫全部死亡,而非Bt玉米对照仅为16.0%,差异显著。田间花丝期人工接种棉铃虫抗性鉴定试验结果表明,Bt玉米雌穗被害率为3.5%,危害级别为0.007,百株存活幼虫14.3头。而非Bt玉米雌穗被害率达到82.5%,危害级别为2.51,平均百株存活幼虫79.6头,显著高于Bt玉米。这些结果说明转Bt基因玉米穗期对棉铃虫的防治效果明理.  相似文献   

6.
10种杀虫剂对斜纹夜蛾的防效比较   总被引:4,自引:1,他引:4  
在室内药效测定的基础上 ,经田间药效试验明确 ,防治斜纹夜蛾 3龄前幼虫效果较好 ,药后 7d防效2.5%功夫乳油和2.5%天王星乳油3000倍液分别为92.39%和89.43% ;20%甲氰菊酯乳油2000倍液为93.32% ;40%毒死蜱乳油1000~2000倍液为97.45%~83.68% ;80%敌敌畏乳油和20%三唑磷乳油1000倍液分别为92.25%和88.24%。  相似文献   

7.
室内试验 1.室内触杀玉米螟幼虫药效测定: 用2.5%溴氰菊酯乳剂,用20—60号筛目的炉渣为载体,配制成不同浓度的颗粒剂,分别按每亩用有效成分药量1克、0.5克、0.25克、0.125克、0.0625克、0.03125克,并设0.1%六六六及5%DDT颗粒剂及不防治为对照,将配好不同浓度用量的药颗粒,分别放在培养皿内,分别在1天、7天、10天,将供试的1龄幼虫(田间采集卵块孵出的1龄幼虫),每一处理接放20头,分别使其在颗粒剂上面爬行30分钟,在幼虫爬行过程中,  相似文献   

8.
南美番茄潜叶蛾Tuta absoluta(Meyrick)是新近传入我国的一种世界毁灭性番茄害虫,对我国番茄产业的潜在威胁巨大。为有效控制南美番茄潜叶蛾,测定了新型苏云金芽胞杆菌基因工程菌G033A(Bt G033A)对该昆虫的室内毒力及田间防效。结果表明,在室内条件下,以32000 IU/mg Bt G033A WP处理过的番茄叶片饲喂南美番茄潜叶蛾幼虫,其室内毒力效果由高至底依次为4龄幼虫,3龄幼虫,1~2龄幼虫,致死中浓度LC50分别为14.63、15.59和23.17 g/L;浓度在10 g/L及以上时,Bt G033A对南美番茄潜叶蛾各龄幼虫的毒力均较高,处理后96 h(第4 d)校正死亡率均超过90%。在田间条件下,以Bt G033A WP 100倍液(10 g/L)喷雾防治低龄幼虫即有较好的防效,药后第5 d对1龄和2龄幼虫的校正死亡率分别为89.1%和98.0%,药后第7 d对1龄和2龄幼虫的校正死亡率均为100%;并且,与常用的生物杀虫药剂鱼藤酮的防效相当。研究结果对有机蔬菜生产基地新发南美番茄潜叶蛾的有效控制及其综合防控方案制定,具有重要指导意义。  相似文献   

9.
绿柳突瓣叶蜂生物学及防治   总被引:1,自引:0,他引:1       下载免费PDF全文
武星煜  辛恒  潘朝晖 《植物保护》2007,33(1):102-105
绿柳突瓣叶蜂(Nematus ruyanus Wei)是发生在甘肃天水柳树上的一种新害虫。严重危害旱柳、垂柳、金丝柳等多种柳树,1年发生6代,非越冬茧结于叶背,越冬茧结于1-5 cm表土中,以预蛹在越冬茧内越冬。幼虫食叶危害,每年3月下旬至10月下旬是该虫的猖獗危害期。用25%灭幼脲,1.8%阿维菌素乳油,40%氧乐果乳油2000倍液防治3龄前幼虫防效达95%以上;用2.5%溴氰菊酯乳油,3%高渗苯氧威乳油4000倍液喷冠防治3龄后大幼虫防效可达90%以上。  相似文献   

10.
2009年在山东省寿光市应用1.2%苦烟乳油对美国白蛾进行了室内、林间防治试验。结果表明,1.2%苦烟乳油1000液和2000倍液,在72h内,均达到理想的防治效果。结合实际情况,林间采用2000倍液比较适宜,施药后96h,幼虫死亡率达到100%。  相似文献   

11.
为寻找有效防控外来入侵物种草地贪夜蛾Spodoptera frugiperda的技术,以烟芽夜蛾囊泡病毒3h株(Heliothis virescens ascovirus 3h,HvAV-3h)为研究对象,通过测定不同龄期草地贪夜蛾幼虫口服或针刺感染HvAV-3h后的死亡率、存活时间、取食量及体重,分析该毒株对草地贪夜蛾幼虫的感染特性及对其生长发育的影响。结果显示,草地贪夜蛾1、2龄幼虫口服HvAV-3h后的校正死亡率分别为9.22%和0,3~6龄幼虫针刺感染HvAV-3h后的校正死亡率则高达100.00%,感染HvAV-3h的幼虫均在幼虫期或蛹期死亡。3~5龄幼虫针刺感染HvAV-3h后的存活时间明显长于健康幼虫;3~6龄幼虫针刺感染HvAV-3h后其体重和取食量均受到不同程度的抑制作用,体重抑制率分别为67.79%、41.68%、16.31%和10.30%,总取食量抑制率分别为57.80%、33.90%、17.42%和41.82%;其中3龄幼虫针刺感染HvAV-3h后的体重和取食量被显著抑制,且蜕皮困难,最终在幼虫期死亡;部分4~6龄感染HvAV-3h幼虫能够完成化蛹,但是均无法羽化。表明HvAV-3h感染能够有效控制草地贪夜蛾幼虫,有望开发为草地贪夜蛾的生防制剂。  相似文献   

12.
The activities of the chitin synthesis inhibitors, diflubenzuron and PH 60–38, against Spodoptera littoralis larvae were assayed by feeding treated alfalfa or poisoned wheat bran baits, by allowing the larvae to imbibe sucrose-containing aqueous dispersions of the compounds, and by injection into larvae. PH 60–38 was less active than diflubenzuron. On alfalfa, diflubenzuron had to be fed for at least 2 days to prevent formation of normal pupae and emergence of adults. For very big (480–540 mg) larvae, feeding diflubenzuron at concentrations of 50 mg/litre for 2 days or 2.5 mg/litre for 3 days prevented adult emergence. For 200–250 mg larvae, this was achieved by feeding concentrations of 100 mg/litre for 2 days, 5 mg/litre for 3 days or 3.5 mg/litre for 4 days. In all larvae > 150 mg, mortality in feeding experiments occurred in the prepupal or the pupal stage. Only with 30–50 mg and 100–150 mg larvae was there considerable mortality during moults between larval instars, the larvae being unable to liberate themselves from the old larval skins and head capsules. Diflubenzuron incorporated into wheat bran baits at concentrations of from 2.5 to 10 000 μg/g killed approximately 70–90% of the insects. When imbibed, diflubenzuron was much less toxic as a wettable powder than as a liquid formulation but the two formulations were equitoxic when injected into the larvae.  相似文献   

13.
在室内用生测法研究了表达Cry1Ab杀虫蛋白的Bt玉米MON810和Bt11小苗和心叶对粘虫Mythimna separata (Walker)初孵幼虫以及玉米叶片对暴食期4龄和5龄幼虫的杀虫效果.结果表明,2种Bt玉米小苗及心叶对粘虫初孵幼虫都具有很好的控制效果,取食MON810和Bt11小苗的粘虫初孵幼虫第1 天的存活率分别为69.44%和86.11%,到第3 天时,取食Bt11小苗的幼虫全部死亡,此时取食MON810小苗的幼虫存活率仅为4.17%,到第7 天全部死亡,而此时在各自相对应的对照玉米DK647和NX4906小苗上幼虫存活率分别为91.66%和88.89%.取食MON810和Bt11心叶的粘虫初孵幼虫第2 天时幼虫存活率急剧下降,分别为13.89%和19.45%,到第7 天时,取食两种Bt玉米心叶的初孵幼虫全部死亡,而取食对照玉米心叶幼虫存活率分别为94.45%和97.22%,差异极显著.两种Bt玉米对粘虫4龄幼虫有很好的杀虫效果,取食的第11天 4龄幼虫全部死亡,对照幼虫存活率均为100%;在Bt11和MON810叶片上取食的粘虫5龄幼虫也不能存活,分别在取食的第11天和12天全部死亡,对照存活率分别为96.00%和98.00%,差异极显著.表明Bt玉米对粘虫初孵幼虫和暴食期的4龄和5龄粘虫都具有显著的致死作用.  相似文献   

14.
Effects of Bollgard II cotton containing two Bacillus thuringensis var. kurstaki Berliner (Bt) toxin proteins (Cry1Ac and Cry2Ab), non-Bt cotton (DPL 491) and starvation on survival and development of cabbage looper, Trichoplusia ni (Hübner), were determined in the laboratory. Larvae of the first four larval instars died when they fed on the terminal leaves of Bt cotton plants at 50 days after planting (DAP). However, 51.3% of fifth instars that fed on 50 DAP Bt cotton leaves pupated, and 87.1% of the pupae successfully developed into adults. Of the unfed fifth instars (starved), 55.6% pupated and 88.1% of the pupae emerged. Pupae that developed from larvae fed on Bt cotton leaves and unfed were significantly smaller, being 89.7 and 73.2% of the weight of the pupae that developed from larvae fed on non-Bt cotton leaves. Leaves of 120 DAP Bt cotton were less toxic to T. ni larvae. When the first instars continuously fed on 120 DAP Bt cotton leaves, 75.9, 60.6, 56.4 and 38.4% of larvae survived to second, third, fourth and fifth instars respectively, and 20.9% pupated and 17.9% successfully became adults. However, it took the surviving first instars 37.1 days to become adults, which was 7.2 and 8.9 days longer than those fed on 50 and 120 DAP non-Bt cottons respectively. Pupae that developed from larvae that fed on 120 DAP Bt cotton leaves were only 50.9 and 52.6% of the weight of those developed from larvae that fed on 50 and 120 DAP non-Bt cotton respectively. Non-Bt cotton, both 50 and 120 DAP, did not exhibit significant effects on larval survival and development, except that the pupae in the 50 DAP non-Bt cotton treatments developed over a significantly longer time than those in the 120 DAP non-Bt cotton treatment.  相似文献   

15.
Potential resistance development to Bt cotton in certain lepidopterans has prompted research to develop strategies that will preserve this environmental-friendly biotechnology. Proteinase inhibitors are potential candidates for enhancing Bt toxicity against lepidopteran pests and for expanding the spectrum of control for other insects. Interactions of Bt toxin from Bacillus thuringiensis and proteinase inhibitors were investigated by monitoring growth, development, and gut proteinase activities of the bollworm, Helicoverpa zea. Several proteinase inhibitors were combined with Bt protoxin Cry1Ac in artificial diet and fed to newly molted 3rd-instar bollworm larvae to determine effects on larval body weight and length, pupation progress, and mortality rate. Major midgut proteinase activities, including caseinase, tryptic, and chymotrypsin activities, were examined after treatment. A concentration of Bt at a level causing minimal mortality (<10%), was mixed with the following proteinase inhibitors: benzamidine, phenylmethylsulfonyl fluoride (PMSF), and N-α-tosyl-l-lysine chloromethyl ketone (TLCK). When compared with controls, the synergistic effect of Bt toxin and proteinase inhibitors caused significant decreases in mean larval weight and length over time. Midgut samples tested against the substrates azocasein, α-benzoyl-dl-arginine-p-nitroanilide (BApNA), and N-succinyl-alanine-alanine-proline-phenylalanine-p-nitroanilide (SAAPFpNA) showed significant decreases in the protease activity of larvae fed Bt plus inhibitor versus control. Interaction of Bt and proteinase inhibitors significantly retarded larval growth and resulted in developmental delay and up to 20% mortality.  相似文献   

16.
Nuclear polyhedrosis virus (NPV) and Bacillus thuringiensis (Bt) are the most commonly used biopesticides for the control of Helicoverpa spp. larvae on cotton crops in Australia. The performance of NPV and Bt against Helicoverpa spp. larvae on cotton crops, is inconsistent and at times totally unsatisfactory against high densities of Helicoverpa spp. larvae. We determined the effect of mixing petroleum spray oils, containing ultra-violet light absorbing compounds, with NPV and Bt for efficacy against Helicoverpa spp. larvae, levels of cotton plant damage, and persistence of efficacy. The study showed that the efficacy and persistence of NPV and Bt were increased when mixed with petroleum spray oil (PSO?–?Canopy®) at the rate of 2% (v/v). In the field experiments, mixing NPV with 1 and 2% (v/v) PSO, increased Helicoverpa spp. mortality from 25.9 to 31.5 and 44.8%, respectively. Similarly, the mortality caused by Bt, when mixed with 1 and 2% (v/v) PSO, was increased from 31.5 to 36.0 and 48.2%, respectively. In addition, 1 and 2% PSO mixtures with NPV increased persistence of efficacy from 1.1 to 1.6 and 2.5 days, respectively, whilst persistence of Bt was increased from 1.5 to 1.8 and 2.6 days, respectively. In another study using potted cotton plants, in which the plants were left outdoors throughout the study, the average NPV induced mortality of first instar Helicoverpa larvae was increased from 20.9% to 35.9 and 43.4% by 1 and 2% (v/v) PSO, respectively. Persistence of NPV efficacy was enhanced by 2 and 3.1 times by 1 and 2% (v/v) PSO, respectively. Similarly, Bt induced mortality of Helicoverpa larvae was increased by 1 and 2% PSO from 68.1 to 78.8 and 83.2%, respectively, and the persistence of Bt efficacy was enhanced 1.3?–?2.0 times, respectively. In a mesh house study, young cotton plants, treated with a PSO/biopesticide mixture, suffered less leaf damage than cotton plants treated with the biopesticides alone. In conclusion, the results of this study showed synergies from the combined use of UV protected PSO and NPV or Bt, against Helicoverpa spp. larvae on cotton. Such a biopesticide-PSO combinations could be a useful tool for IPM program in cotton.  相似文献   

17.
室内应用斯氏线虫3个种的5个品系,对越冬沟眶象幼虫进行侵染力比较,结果表明,施线虫后8天,芜菁夜蛾线虫A24品系和Beijing品系,可使在土壤内的幼虫死亡率分别达100%和90%,14天后Beijing品系的致死率亦达100%,其它3个品系均达90%左右;在土壤含水量为10~20%范围内,幼虫死亡率随土壤含水量的增加而递增,施线虫后5天,含水量20%的处理,幼虫死亡率达70%,而10~15%含水量中,死亡率为45~50%;线虫对沟眶象成虫的致死率很低仅15%。对为害臭椿树的沟眶象幼虫,用A24和Beijing品系进行防治,效果分别为77.3%和70.0%。  相似文献   

18.
试验选用25 g/L溴氰菊酯、40%氧乐果乳油、啶虫脒、40%辛硫磷、80%敌敌畏乳油、茶皂素、10%吡虫啉可湿性粉剂、45%杀螟硫磷等药剂对星天牛幼虫进行浸泡处理,并研究了部分药剂的混配浸泡效果,得出结果:溴氰菊酯500倍、溴氰菊酯500倍+啶虫脒500倍、辛硫磷500倍+敌敌畏500倍处理星天牛幼虫15 min,4d后幼虫死亡率达到100%。在对红枫嫁接苗中星天牛幼虫的药剂浸泡试验中,溴氰菊酯500倍处理在浸泡48 h、辛硫磷500倍+敌敌畏500倍处理在浸泡36 h都可完全杀死星天牛幼虫。  相似文献   

19.
Mosquito netting side panels of targets used for tsetse control were treated with lambda-cyhalothrin, either dissolved in a mixture of acetone and a chlorohydrocarbon oil, ‘Cereclor’® > (ICI, UK) or as a conventional wettable powder formulation suspended in water. Treated netting samples were weathered under natural conditions in full sun in Zimbabwe. Following brief tarsal contact of test insects (adults of Glossina morsitans morsitans Westw.) with treated netting, the wettable powder induced 100% knockdown for four months after treatment but 24-hour mortality levels were reduced from the third month onwards. The oil formulation induced 100% knockdown for up to ten months following treatment and 100% mortality at 24 hours for up to eight months. Chemical assay showed that after two months there had been a rapid reduction in the amount of active ingredient to only 20% of that applied using the wettable powder, whereas the oil formulation took seven months to fall to this level. Provided that at least 5% of the original amount of pyrethroid remained on the fabric it was quite effective and the superiority of the oil formulation was further enhanced by the observation that the starting concentration was only 25% of that of the wettable powder.  相似文献   

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