The relative toxicities of insecticides to earthworms of the Pheretima group (Oligochaeta)

An artificial soil test was used to determine the LC50 values of carbaryl, chlorpyrifos, imidacloprid, cyfluthrin and fipronil against earthworms of the Pheretima group. For a 24-h interval, carbaryl was the most toxic to earthworms (LC50 = 77 mg kg-1), followed by imidacloprid (155 mg kg-1), cyfluthrin (351 mg kg-1), chlorpyrifos (390 mg kg-1) and fipronil (> 8550 mg kg-1) as the least toxic. For the 48-h and 7-day intervals, imidacloprid was the most toxic to earthworms (LC50 = 5 mg kg-1 and 3 mg kg-1 respectively), followed by carbaryl (16 mg kg-1; 9 mg kg-1), cyfluthrin (128 mg kg-1; 110 mg kg-1), chlorpyrifos (330 mg kg-1; 180 mg kg-1) and the least toxic was fipronil (> 8550 mg kg-1 both intervals). The surface application rates required to achieve these values are compared with the rates recommended for the control of turfgrass pests.     

拌种防治花生田金针虫药剂筛选及其安全性研究

为了筛选拌种防治沟金针虫[Pleonomus canaliculatus(Faldermann)]安全有效的药剂和剂型,通过田间试验及对花生籽粒中农药残留和品质检测,对参试药剂效果和安全性进行评价。结果表明:5%氟虫腈悬浮种衣剂拌种可达到全生长季控制花生田金针虫的危害,防虫、保果效果和产量增加分别为98.53%、97.30%和33.33%,显著高于毒死蜱、吡虫啉、阿维菌素;30%毒死蜱微囊悬浮剂拌种防虫、保果效果分别为72.18%、79.96%,优于吡虫啉和阿维菌素;吡虫啉70%种子处理可分散粉剂保果防虫效果优于10%微囊悬浮剂;复配剂42%氟虫腈·吡虫啉悬浮剂和16%阿维·毒死蜱微囊悬浮剂防虫、保果和产量增加分别与氟虫腈和毒死蜱相当,无显著差异。所有参试药剂拌种对花生出苗率、花生生长和品质无不良影响,产量增加明显,花生籽粒中农药残留低于国内外农药残留限量。因此,5%氟虫腈悬浮种衣剂是拌种防治花生金针虫安全有效的理想药剂,30%毒死蜱微囊悬浮剂也可作为拌种防治花生金针虫安全有效的药剂之一。     

Toxicity and neurophysiological effects of selected insecticides on the mole cricket, Scapteriscus vicinus (Orthoptera: Gryllotalpidae)

Mole crickets (Scapteriscus spp.) are severe subterranean pests of turfgrasses, commonly targeted with neurotoxic insecticides. Ideally insecticides used against mole crickets should induce quick knockdown or mortality to minimize damage caused by their tunneling. However, neurophysiological effects of insecticides on mole crickets are mostly unknown. The aims of this study were to investigate neurophysiological and toxic effects of several insecticides on tawny mole cricket (Scapteriscus vicinus Scudder) adults and nymphs, and potential synergy between pyrethroid and neonicotinoid insecticides. Bifenthrin, fipronil, and the combination of bifenthrin + imidacloprid provided the fastest median mortality when injected. The combination of bifenthrin + imidacloprid elicited faster toxicity than either active ingredient alone. Imidacloprid, bifenthrin, and bifenthrin + imidacloprid caused immediate knockdown, whereas fipronil immobilized mole crickets within 1-2 h. Acephate, bifenthrin, fipronil, imidacloprid, and bifenthrin + imidacloprid caused significant neuroexcitation. Bifenthrin + imidacloprid resulted in greater increases of spontaneous neural activity than the additive effects of imidacloprid and bifenthrin alone. Excitatory compounds acting at sodium and chloride channels (bifenthrin and fipronil) were the most toxic against S. vicinus. Combining a sodium channel toxin (bifenthrin) and a synaptic toxin (imidacloprid) led to greater than additive neurophysiological and toxic effects, which to our knowledge provides the first documented evidence of synergistic neurological “potentiation”.     

梨叶甲药剂防治试验

4种杀虫剂对梨叶甲幼虫的田间防治试验结果表明,52.25%毒•高氯乳油、1.8%阿维菌素乳油、2.5%高效氟氯氰菊酯乳油、10%吡虫啉可湿性粉剂均是防治梨叶甲幼虫的有效药剂,药后第1天、第3天、第7天的相对防效分别为94.64%~99.26%、94.84%~100%、83.87%~100%。     

Influence of Portland cement amendment on soil pH and residual soil termiticide performance

Soil adjacent to new brick veneer work is likely to have a higher pH owing to the mixture of cement with the soil. In the Gainesville, FL, area, soil samples taken from such locations had a range of pH values from 9.0 to 10.1; similar soils used in bioassays had a pH of 5.6 before the addition of cement. Addition of 15 mg of Portland cement to 33 g of soil increased the pH to 6, and addition of 291 mg of Portland cement increased the pH to 9. The pH of soil amended with cement was stable for the first 5 months. After 10 months, soil pH values decreased from alkaline to near neutral in all cases. Eastern subterranean termite workers, Reticulitermes flavipes (Kollar), were exposed to the treated soil at pH 6-9 for 24 h, and percentage mortality was recorded at 5 days, 5 months and 10 months. Termite mortality significantly decreased at higher soil pHs for bifenthrin, chlorpyrifos, fipronil and imidacloprid treatments at 5 months and similarly for bifenthrin, permethrin, chlorpyrifos, fipronil and imidacloprid treatments at 10 months. There was an inverse linear relationship between soil pH and mortality. Increased soil pH diminished residual activity of termiticide in the following order: imidacloprid > fipronil > chlorpyrifos = bifenthrin > permethrin > cypermethrin.     

转crylA基因水稻和两种杀虫剂对非靶标天敌拟环纹豹蛛免疫影响的评价

本文测定了田间转crylAb基因水稻（KMDl和KMD2）和两种杀虫剂（吡虫啉和氟虫腈）处理非转基因亲本秀水11后拟环纹豹蛛Pardosapseudoannulata的免疫指标（血细胞总数、包囊能力和酚氧化酶活性）的变化,并以非转基因亲本秀水11无药剂处理的作为对照。研究结果表明,KMDl和KMD2对拟环纹豹蛛的3种免疫因子都没有显著影响;两种杀虫剂处理均导致拟环纹豹蛛的血细胞数量和包囊能力显著下降,酚氧化酶活性略低于对照,即对拟环纹豹蛛的免疫有负面影响。可见,非靶标天敌的免疫能力可考虑作为转基因水稻环境安全性评价的一个简单有效的指标。     

河北省不同地区韭蛆(韭菜迟眼蕈蚊)对杀虫剂的敏感性

韭蛆——韭菜迟眼蕈蚊 ( Bradysia odoriphaga)是为害韭菜、葱、蒜等经济作物的重要地下害虫之一 [1～ 4]。各地防治韭蛆均以灌施化学农药为主 ,使用的品种主要为有机磷农药 ,如辛硫磷、毒死蜱等。在河北省不同韭菜主产区 ,同种药剂使用量相差很大 ,可能是由于不同地区韭蛆对药剂的敏感性不同 ,然而尚未见有关不同地区韭蛆对各种药剂敏感性的研究报道。为了探明河北省不同地区韭菜田韭蛆对几种杀虫剂的敏感性 ,作者于 2 0 0 0年 4月对保定市郊区、定州市、肃宁县和永年县韭菜田韭蛆对几种杀虫剂的敏感性进行了测定 ,同时测定比较了韭菜田和…     

毒死蜱、噻嗪酮对褐飞虱的防控效果分析

通过分析用药后低龄若虫、高龄若虫和成虫的数量消长情况,对毒死蜱和噻嗪酮2种药剂防治褐飞虱的效果进行了研究。结果表明,使用这2种杀虫剂后,虽然田间褐飞虱卵能持续孵化,从而使总体防效降低,但这2种药剂均能有效减少高龄若虫数量,其中噻嗪酮在长达1个多月的时间内能阻止褐飞虱由低龄向高龄转化,毒死蜱的抑制有效期大约为10d。这2种药剂主要是通过在稻株上的残留来杀死低龄若虫,从而发挥其药效作用。通过本研究,有助于正确评价药剂对褐飞虱的防效,从而为防治决策提供可靠依据。     

Identification and expression profiles of nine glutathione S-transferase genes from the important rice phloem sap-sucker and virus vector Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae)

BACKGROUND: Glutathione S‐transferases (GSTs) have received considerable attention in insects for their roles in insecticide resistance. Laodelphax striatellus (Fallén) is a serious rice pest. L. striatellus outbreaks occur frequently throughout eastern Asia. A key problem in controlling this pest is its rapid adaptation to numerous insecticides. In this research, nine cDNAs encoding GSTs in L. striatellus were cloned and characterised. RESULTS: The cloned GSTs of L. striatellus belonged to six cytosolic classes and a microsomal subgroup. Exposure to sublethal concentrations of each of the six insecticides, DDT, chlorpyrifos, fipronil, imidacloprid, buprofezin and beta‐cypermethrin, quickly induced (6 h) up‐expression of LsGSTe1. The expression of LsGSTs2 was increased by chlorpyrifos, fipronil and beta‐cypermethrin. Furthermore, exposure of L. striatellus to fipronil, imidacloprid, buprofezin and beta‐cypermethrin increased the expression of the LsGSTm gene after 24 or 48 h. CONCLUSION: This work is the first identification of GST genes from different GST groups in Auchenorrhyncha species and their induction characteristics with insecticide types and time. The elevated expression of GST genes induced by insecticides might be related to the enhanced tolerance of this insect to insecticides and xenobiotics. Copyright © 2012 Society of Chemical Industry     

阿维菌素与三种杀虫剂对西花蓟马的联合毒力

阿维菌素是防治西花蓟马的常用药剂,为筛选出对西花蓟马具有增效作用的阿维菌素与其他药剂的混配组合,采用浸叶法测定了阿维菌素、毒死蜱、吡虫啉和吡蚜酮等药剂对西花蓟马2龄若虫的毒力,并通过共毒因子法和共毒系数法分别确定了最佳药剂配伍和最佳复配比例。结果表明,阿维菌素与毒死蜱复配表现出明显的增效作用;阿维菌素与毒死蜱比值为2∶8与8∶2时,增效作用最显著;阿维菌素与吡蚜酮、吡虫啉均表现出拮抗作用。     

Efficacy of insecticides through contact and oral uptake towards four Agriotes wireworm species under controlled conditions

Wireworms of Agriotes lineatus, A. obscurus, A. sputator and A. sordidus were exposed to insecticide treated soil using two different control methods. One method consisted of a spray application of insecticides at doses of 50, 100, 200, and 300 g a.i. per ha. The other method consisted of a bait treatment at doses of 0.01, 0.1, 1, and 10 g a.i. per ha. Four insecticides were tested: fipronil and the neonicotinoids thiamethoxam, imidacloprid and clothianidin. In the soil treatment trial, chlorpyrifos was added as a reference treatment. The two test methods were conducted at different dates on the various species, but in equally controlled conditions. Mortality was observed after one and two (bait treatment) or three (soil treatment) weeks of exposure. Fipronil was highly lethal to each of the wireworm species tested, regardless of the method used. In general, mortality was higher compared to the neonicotinoids tested, the latter showing low or no mortality at the given dose and exposure variants. Applying fipronil in a bait formulation may decrease the amount of active ingredient per ha considerably, therefore baits may have important environmental benefits.     

稻纵卷叶螟防治药剂筛选试验

本试验认为锐劲特、乙酰甲胺磷、毒死蜱、精虫杀手、纵卷清等防治稻纵卷叶螟效果显著，防效在89%以上，适合取代即将禁止使用的常规高毒农药甲胺磷。     

1.6%瑞香狼毒素水乳剂对4种蔬菜害虫的作用方式比较

采用叶片夹毒法、微量点滴法和玻片浸渍法等方法测定了1.6%瑞香狼毒素水乳剂对菜青虫、小菜蛾、豌豆蚜和截形叶螨的杀虫效果。结果表明:处理24h后,在触杀活性试验中,1.6%瑞香狼毒素水乳剂对试虫的毒力大小为菜青虫小菜蛾豌豆蚜截形叶螨;在内吸活性试验中,1.6%瑞香狼毒素水乳剂对截形叶螨和豌豆蚜的LC50分别为149.22mg/L和101.76mg/L,均小于触杀作用下的219.10mg/L和165.25mg/L,表明1.6%瑞香狼毒素水乳剂对豌豆蚜和截形叶螨内吸毒性明显优于触杀作用;在胃毒活性试验中,1.6%瑞香狼毒素水乳剂对菜青虫和小菜蛾的LC50分别为342.82mg/L和407.34mg/L,而触杀作用下的LC50为58.61mg/L和75.30mg/L,表明该药剂对菜青虫和小菜蛾有较强的触杀作用和一定的胃毒作用。     

八种杀虫剂对黑粪蚊的防治效果及残留分析

选择8种杀虫剂,分别在实验室和菇房条件下研究其对黑粪蚊的防治效果和对平菇菌丝生长的影响,并分析施药后不同时间平菇中的农药残留.结果表明,40%辛硫磷EC、40%氧乐果EC、48%毒死蜱EC对黑粪蚊具有很好的防治效果,但对平菇菌丝的抑制率明显高于其它药剂;10%吡虫啉WP、4.5%高效氯氰菊酯EC不仅对黑粪蚊成、幼虫具有良好的防治效果,而且使用后对平菇菌丝生长的影响较小;2.5%高效氯氟氰菊酯EW、4.5%高效氯氰菊酯EC、1.8%阿维菌素EC等使用5天后均未检测到农药残留,5%氟虫腈SC和10%吡虫啉WP药后15天仍能检测到残留.     

3种白蚁防治药剂对散白蚁的控制效果观察

2010年-2012年应用吡虫啉10%悬浮剂、联苯菊酯5%悬浮剂和氟虫腈0.5%粉剂等3种白蚁防治药剂对危害房屋建筑的散白蚁进行了针对性处理,对其防治效果进行了观察和统计研究。结果表明：吡虫啉10%悬浮剂、联苯菊酯5%悬浮剂、氟虫腈0.5%粉剂对房屋建筑散白蚁危害的控制率分别为：85.30%、84.01%、80.33%,具有较好的防治效果,且吡虫啉10%悬浮剂、联苯菊酯5%悬浮剂防效均显著高于氟虫腈0.5%粉剂。此外,对3种白蚁防治药剂处理后再次发生蚁害的情况进行了分析。     

Degradation of bifenthrin,chlorpyrifos and imidacloprid in soil and bedding materials at termiticidal application rates

Organophosphorus, pyrethroid and chloronicotinyl insecticides have been used to control termites in building structures in recent years. We investigated the degradation behaviour of three insecticides (bifenthrin, chlorpyrifos and imidacloprid) at termiticidal application rates under standard laboratory conditions (25 °C, 60% field moisture capacity and darkness) for 24 months. The study was carried out on one soil and two bedding materials (sand-dolomite and quarry sand), which are commonly used under housing in Australia. Experiments were also conducted to examine the effect of soil moisture on the degradation of these insecticides. Insecticide residues in the samples collected at different days after application were measured by high performance liquid chromatography (HPLC). The rate of degradation of bifenthrin and imidacloprid insecticides was adequately described by a first-order kinetic model (r² = 0.93–0.97). However, chlorpyrifos degradation was biphasic, showing an initial faster degradation followed by a slower rate. Therefore, the degradation data during the slower phase only (after a two-month period) followed the first-order law (r² = 0.95). Soil moisture had little effect on degradation of imidacloprid and bifenthrin. Among the three insecticides, bifenthrin and imidacloprid were most stable and chlorpyrifos the least. Chlorpyrifos showed a major loss (75–90%) of residue during the 24 months incubation period. In the bedding materials, simultaneous accumulation of the primary metabolite of chlorpyrifos, TCP (3,5,6-trichloro-2-pyridinol) was observed. Hydrolysis appeared to have caused the observed rapid loss of chlorpyrifos, especially in the highly alkaline bedding materials (sand-dolomite and quarry sand). © 1999 Society of Chemical Industry     

密褐褶孔菌Gloeophyllum trabeum对几种杀虫剂跟踪反应及对水坝白蚁诱杀效果的影响

测定了毒死蜱、氰戊菊酯、阿维菌素和氟虫腈等 4种杀虫剂与不同饵料混合后对家白蚁 Coptotermes formosanus和黄肢散白蚁 Reticulitermes flaviceps的口服毒性。在此基础上比较了各种饵料及由它们配成的毒饵对黄肢散白蚁的引诱力。结果表明 ,白蚁对甘蔗粉的喜好程度远超过对淀粉和松木粉。而受密褐褶孔菌 Gloeop hyllum trabeum侵染的甘蔗粉对白蚁的引诱力又远超过未受侵染的甘蔗粉。 4种杀虫剂中除氰戊菊酯外 ,另 3种与受侵染甘蔗粉制成的毒饵均能够在不损失杀白蚁活性的同时保留其对白蚁的引诱力。其中毒死蜱毒饵在为期30 d的水坝白蚁诱杀防治中取得最高 (6 6 .7% )的防治效果。     

杀虫剂对韭菜迟眼蕈蚊毒力与药效相关性研究

韭菜迟眼蕈蚊Bradysia odoriphaga 以幼虫蛀食韭菜根茎造成危害,为使毒力测定方法与田间幼虫受药方式具有较高程度的一致性,建立了胃毒触杀联合毒力测定法,利用该方法测定了分属三个类别的4种杀虫剂即毒死蜱、辛硫磷、丙硫克百威、吡虫啉对韭菜迟眼蕈蚊3龄幼虫的毒力,以辛硫磷为标准药剂,毒死蜱、吡虫啉和丙硫克百威的相对毒力倍数分别为10.36、2.61和2.30。田间达到50%防效所需药剂浓度以辛硫磷为最高,毒死蜱、吡虫啉和丙硫克百威对辛硫磷的防效比值分别为9.58、1.88和2.05。胃毒触杀联合毒力法测得的药剂毒力高低排序及相对毒力倍数与田间小区试验结果基本一致,与常规的单一触杀法比较,该法测定结果的重现性好,并且与田间药效试验结果相关性高。同时讨论了不同操作方法对室内毒力测定结果的影响。     

中国主要蜜源作物上登记的农药品种及其中杀虫剂对蜜蜂的初级风险评估

对目前中国主要蜜源作物上登记的农药品种进行了梳理,并采用现有的风险评估标准方法,对其中毒死蜱、吡虫啉等共61种杀虫剂对蜜蜂的风险进行了初级评估。结果表明:在58种喷雾施用的杀虫剂中,35种对蜜蜂的风险商值均大于1,风险为不可接受;其余23种的风险商值小于1,风险为可接受;所评估的6种土壤或种子处理内吸性杀虫剂中,5种对蜜蜂的风险商值大于1,风险为不可接受,仅氯虫苯甲酰胺的风险商值小于1,风险为可接受。但由于文中是以药剂在所登记作物上的单次最高施药剂量为暴露量进行的初级评估,并未考虑农药在花粉、花蜜中的降解及降雨引起的淋洗损耗,以及施药时间与作物花期之间的关系等影响因素,因而使得评估结果具有较大的保守性。研究结果一方面可为这些农药的合理使用和管理提供参考,另一方面提示了目前中国关于农药对蜜蜂的初级风险评估程序需进一步优化。     

Effects of insecticides on plant-growth-promoting activities of phosphate solubilizing rhizobacterium Klebsiella sp. strain PS19

In this study, four technical grade insecticides, fipronil, pyriproxyfen, imidacloprid and thiamethoxam were applied at the recommended and the higher doses to investigate their effects on plant growth-promoting activities of phosphate-solubilizing Klebsiella sp. strain PS19, isolated from mustard rhizosphere. All tested insecticides displayed a concentration-dependent inhibition in plant growth promoting traits, like, inorganic phosphate solubilization, biosynthesis of phytohormones and siderophores, of rhizobacterial strain PS19. For example, the phosphate-solubilizing activity of Klebsiella sp. PS 19 was reduced maximally by 95%, at 3900 μg l⁻¹ pyriproxyfen over control. At the recommended rate, the magnitude of toxicity of insecticides to plant growth promoting traits was less severe compared to the higher doses. The sequence of insecticide-toxicity expressed as percent decrease, determined at highest dose rate of each insecticide, over control was: pyriproxyfen (95) = imidacloprid (95) > thiamethoxam (94) > fipronil (85), for phosphate-solubilizing activity while for salicylic acid (SA) it was: thiamethoxam > pyriproxyfen = imidacloprid > fipronil. The impact of the highest dose rate of insecticides on 2,3-dihydroxybenzoic acid (DHBA) was almost equal to those observed for SA. Thiamethoxam decreased the indole acetic acid (IAA) synthesis maximally by 86% whereas fipronil had least toxicity and reduced it by 67% relative to the control. Among the experimental insecticides, pyriproxyfen at 3900 μg l⁻¹ in general, had the greatest toxic effects for plant growth promoting activities of the test strain. The study inferred that insecticides affect the plant beneficial activities of rhizobacteria adversely. These findings are likely to add a new insight into the pest management practices.