Permethrin as a residual insecticide against cockroaches

The pyrethroid permethrin was shown to be active against Blattella germanica, Periplaneta americana and Blatta orientalis. In laboratory tests on plywood panels the best formulation was a 25% wettable powder which showed an initial LC₅₀ of 10 mg m^?2 against B. germanica and lost activity at the weekly rate of 1.9 mg m^?2. An initial deposit of 108 mg m^?2 gave 50% kill after one year. The synergist piperonyl butoxide diminished residual performance. In one field trial, good control was maintained for more than four months with an initial deposit of 50 mg m^?2, the smallest dose used. From this and other trials, the recommended rate of application for general use in long-term control is 100 mg m^?2. A distinctive slow expellent action against B. germanica was seen in field trials.     

Oil formulation of pyrethroids for contamination of tsetse flies (Glossina spp.) through tarsal contact with treated targets

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.     

Influence of particle size and type of formulation on phytotoxicity and persistence of atrazine

The initial and residual activities of wettable powder formulations of atrazine comprising different particle sizes were investigated in field and glasshouse experiments. A flowable formulation was also compared with these. Oats were used as the test species for the glasshouse studies while in field trials effects on control of broadleaf weeds in maize were studied. No marked differences were noted in the activity of wettable powders of different particle sizes in the glasshouse as pre-emergence applications. As a post-emergence treatment the fine particle size was more phytotoxic than the coarse material, especially when a wetting agent was added to the spray solution. In the field trials, no appreciable differences in weed control or crop tolerance could be established regardless of the time or rate of application. The flowable formulation was less active than the wettable powders in some glasshouse experiments but no such trend was apparent in field trials. Bioassays showed that the residual activity of the flowable formulation was lower than wettable powder formulations in both glasshouse and field studies but no consistent differences were noted in the persistence of the three forms of wettable powders.     

The persistence of insecticide spray deposits on woven polypropylene and jute sacking

In a trial, simulating the spray treatment of bags, the persistence and biological activity of insecticide spray deposits on jute and woven polypropylene sheets have been compared; in addition, the build-up of residues in thin layers of maize under the sprayed sheets has been measured. The insecticides were found to have a much shorter persistence on polypropylene than on jute and this was coupled with higher residues on the grain. However, the deposits on polypropylene retained equal or greater activity against Sitophilus zeamais Motsch. and Tribolium castaneum (Herbst) than the deposits on jute, despite the loss of surface deposit. Wettable powder formulations had a slightly greater surface persistence than emulsifiable concentrates and resulted in smaller residues in the grain. There would seem to be more usefulness in using insecticide sprays on woven polypropylene than on jute bags, and a wettable powder formulation of a non-volatile insecticide of low mammalian toxicity would be the best choice. Of the insecticides tested, the pyrethroid permethrin (cis: trans ratio= 25:75) was the most effective and gave the least residue in the grain.     

农用微生物杀菌剂剂型研究进展

农用微生物杀菌剂的主要剂型有粉剂(DP)、可湿性粉剂(WP)、颗粒剂(GR)、水分散粒剂(WG)和悬浮剂(SC)等。我国现有的农用微生物杀菌剂剂型种类较为单一,主要为可湿性粉剂,未来应加强其他剂型如水分散粒剂和悬浮剂等的研究开发。生防菌的活菌数、制剂加工和贮存条件以及田间环境因素等对农用微生物杀菌剂的防效均有很大影响,科学合理地评价这些影响,并研究其形成原因和内在规律,对农用微生物杀菌剂的深入研究开发具有重要意义。文章从剂型种类、性质、质量控制以及生产条件、贮存条件和田间环境条件对制剂性质与防效的影响等方面,对农用微生物杀菌剂剂型的研究现状和存在问题进行了详细的综述,并分析了其未来发展趋势。     

Retention of iprodione on salad onion leaves in relation to the control of Botrytis spp.

Using bioassay and fluorescent tracer techniques it was demonstrated that more fungicide was retained on mature leaves of summer salad onion crops if 1 kg/ha iprodione wettable powder (w.p.) formulation plus wetting agent was sprayed at 280 1/ha than at 560 1/ha or 1120 1/ha.
The lowest spray volume (280 1/ha) with four sprays of iprodione w.p. (0.5 kg in October, November, December and January) gave effective control of Botrytis cinerea and significantly increased plant stand and yield. More fungicide was required to obtain equivalent results using a mixed programme of two thiram (4 kg/ha total) and two iprodione w.p. (2 kg a.i./ha total) sprays at the same application volume and intervals. Where the mixed programme was applied at 1 1 20 1/ha, 1 2 kg a.i. (total fungicide) was necessary to achieve equivalent disease control.
At 280 1/ha, retention and persistence of iprodione on onion foliage was greater with the oil-based than with the wettable powder formulation. In summer especially this resulted in improved Botrytis control and greater numbers of marketable onions. In winter onions, oil and w.p. formulations were equally effective and gave equivalent improvements in plant stand and yield.     

吡虫啉和啶虫脒在两种叶菜上残留的原始沉积行为及其影响因素

叶菜上农药原始沉积行为受作物形态、农药种类及其剂型、施用方式等多种因素的影响,是评估农药残留的重要指标。以吡虫啉和啶虫脒为目标农药,以菠菜和生菜作为靶标作物,通过农药施用后的原始沉积行为,以及兑水量、叶面积指数和农药剂型对农药沉积的影响,初步揭示了农药原始沉积规律。结果表明：施药后0.5～8 h内其沉积量无显著差异,综合考虑,选择施药后2 h时测定其原始沉积量;两种农药在菠菜和生菜中主要沉积在叶片表面,沉积量占比均在87%以上,在根和土壤中的沉积量较少;农药施药剂量相同而兑水量不同,则原始沉积量存在显著差异,随着兑水量的增加,沉积量逐渐减少;菠菜和生菜中农药沉积量与叶面积指数呈负相关;原始沉积量与剂型也有相关性,在施药剂量相同时,吡虫啉在菠菜、生菜中原始沉积量最高均为可湿性粉剂,沉积量分别为0.66和0.77 mg/kg;啶虫脒在菠菜中原始沉积量最高为乳油和可湿性粉剂,沉积量均为0.65 mg/kg,生菜中原始沉积量最高为可湿性粉剂,沉积量为0.37 mg/kg。研究结果认为,农药剂型、兑水量和叶面积指数均会影响叶菜表面农药原始沉积量,该结果可为叶菜中农药合理安全施用和农药残留管控提供...     

球孢白僵菌400亿孢子／克防治美国白蛾药效试验

为解决当前美国白蛾在杨树上发生严重的问题,本研究以常用药剂灭幼脲25％悬浮剂为对照．在田间杨树上测试了2年球孢白僵菌400亿孢子／克可湿性粉剂在不同使用浓度下对美国白蛾的防治效果。结果表明,球孢白僵菌400亿孢子／克可湿性粉剂相对于灭幼脲25％悬浮剂表现出很好的防治效果,2年的防效均在90％以上。该试验结果为该药剂的产品登记以及为生产上选择适于防治美国白蛾的药剂种类提供了依据。     

环已磺菌胺·百菌清50％可湿性粉剂的配方研究

通过对载体、润湿剂、分散剂类型和用量的研究,确定了环己磺菌胺·百菌清50％可湿性粉剂的最佳配方,并测定了制剂的质量控制指标,各项指标符合可湿性粒剂的要求.对黄瓜霜霉病的温室盆栽进行了药效试验,结果表明：所制成的制剂对黄瓜霜霉病的防治效果优于单剂.     

猕猴桃灰霉病拮抗解淀粉芽孢杆菌X17可湿性粉剂的研制

以植物内生解淀粉芽孢杆菌X17为研究对象,通过对载体、分散剂、润湿剂、稳定剂、保护剂的筛选,确定了内生解淀粉芽孢杆菌X17可湿性粉剂最佳配方:硅藻土10%,羧甲基纤维素钠4%,十二烷基硫酸钠6%,甲基纤维素2%,糊精0.1%。结果显示,制备的解淀粉芽孢杆菌X17可湿性粉剂在25℃室温下芽孢含量为2.0×10¹⁰cfu/g,pH7.0,悬浮率78%,润湿时间35s,细度通过率99%,制剂贮藏6个月存活率达78%。盆栽试验结果表明,内生解淀粉芽孢杆菌X17可湿性粉剂和母粉500倍液对猕猴桃灰霉病的保护效果分别为80.59%和68.82%,菌株X17可湿性粉剂的防治效果优于其母粉。     

白僵菌可湿性粉剂的研制

以白僵菌孢子粉为原药,硅藻土为主要载体,通过单因素和正交设计筛选合适的润湿剂、分散剂等助剂配方比例,研制出性能优良的白僵菌可湿性粉剂。确定配方为：白僵菌分生孢子粉20%; NNO7%; 农乳32082%; 拉开粉5%; 十二烷基硫酸钠2%; 硅藻土加齐至100%。质量检测结果表明：该配方润湿时间<1min,悬浮率可达到75%以上,其他各项指标均符合可湿性粉剂的要求。     

Evaluation of different formulations of deltamethrin in comparison with permethrin for impregnation of netting

Five formulations of deltamethrin and one of permethrin were impregnated into cotton and nylon netting and tested for their efficacy and persistence in killing Anopheles gambiae Giles which were attempting to penetrate the netting in search of blood meals. Emulsifiable concentrates persisted better than wettable powders of deltamethrin, and all the deltamethrin formulations performed better than permethrin, even though the latter was applied at an eight times higher dose. The insecticidal effect of both compounds persisted better on nylon than on cotton; it was adversely affected by repeated washing.     

海洋多黏类芽胞杆菌可湿性粉剂的研制

以海洋多黏类芽胞杆菌Paenibacillus polymyxa为研究对象,通过单因素室内试验和田间试验,确定了可湿性粉剂配方及其对甜瓜枯萎病的田间防效。结果表明,可湿性粉剂最佳配方为:以皂土为载体的菌粉70%,稳定剂海藻酸钠14%,湿润剂蔗糖脂肪酸酯8%,分散剂聚乙烯醇8%。制得的可湿性粉剂活菌数为1.23×10^10cfu/g,含水量6%,润湿时间48 s,悬浮率75%,杂菌率0。采用7种不同方法防治甜瓜枯萎病,结果表明,可湿性粉剂对甜瓜枯萎病的综合防治效果高达84.9%。该制剂对甜瓜枯萎病具有良好防效,可作为防治甜瓜枯萎病的药剂在生产上推广应用。     

Effect of 2,6-dichloroisonicotinic acid, its formulation materials and benzothiadiazole on systemic resistance to alternaria leaf spot in cotton

A wettable powder (WP) formulation providing 5–25 μg mL⁻¹ of 2,6-dichloroisonicotinic acid (INA) and 15–75 μg mL⁻¹ of WP applied to cotton cotyledons significantly increased the resistance of the next two leaves to challenge inoculation by Alternaria macrospora . The wettable powder alone at 15–75 μg mL⁻¹ had a lesser effect. A wettable granule (WG) formulation supplying 35 μg mL⁻¹ of benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) and 35 μg mL⁻¹ of WG, applied as a cotyledonary treatment, significantly reduced the formation of lesions on the subsequent two leaves when challenged with A. macrospora . The WG control had no effect. Each treatment except for the WG control also raised the activities of β-1,3-glucanase in unchallenged leaf and stem tissue. Each of the components of the wettable powder without INA applied to cotyledons raised enzyme activities in the next leaves. Individual components, as suspensions of silicic acid and kaolin and solutions of the detergent Attisol II, the wetting agent Ultravon W300 and pure INA, applied to cotyledons increased the resistance of the next leaves to A. macrospora . The responsiveness of cotton to BTH and to each of the components of formulated INA is discussed in relation to knowledge of the effects of BTH and INA on other plants and to possible ways in which the other components of the wettable powder may affect the process of signalling for systemic resistance to disease.     

Determination of imidazolidine-2-thione (ethylenethiourea) in ethylenebisdithiocarbamate formulations

Zineb was most seriously contaminated with imidazolidine-2-thione (ethylenethiourea; ETU), followed by mancozeb, and maneb. The type of formulation also affects ETU generation and a wettable powder produced ETU more easily than a flowable formulation. The ETU contents of the ethylene-bisdithiocarbamate (EBDC) mixed fungicides formulations were erratic. Low ETU contents were found in EBDC mixed fungicides, even though some samples had been stored in the laboratory for five years. The cupric ion and the N, O-containing group of other fungicides might have a stabilizing effect on the degradation of EBDC to ETU. The survey indicated that EBDC mixed formulations could be a useful means of suppressing ETU generation in commercial products.     

20%异丙甲 ? 苄泡腾片剂的研制及其对稻田杂草的防治效果

为了提高稻田杂草化学防除的省力化程度，降低防治成本，通过单一变量法筛选配方中的助剂种类和用量，采用干法压片工艺制备了20%异丙甲 ? 苄泡腾片剂 (有效成分异丙甲草胺 + 苄嘧磺隆)，同时进行了田间药效评价。结果表明:20%异丙甲 ? 苄泡腾片剂的优化配方(质量分数)为:16%异丙甲草胺，4%苄嘧磺隆，18%有机膨润土，9%白炭黑，20%酒石酸，20%碳酸氢钠，6%润湿剂EFW，4%分散剂G202和3%润滑剂硬脂酸镁。该泡腾片剂在有效成分120~180 g/hm2 的用量范围内能有效防除稻田杂草，防效明显优于其单剂，与已登记的20%异丙甲 ? 苄(有效成分质量比17 : 3)可湿性粉剂相当，持效期达40 d以上。所研制的20%异丙甲 ? 苄泡腾片剂表面光滑，无粉尘，使用方便，省时省工，对稻田常见杂草均有良好防效，持效期长，具有推广价值。     

50000 IU/mg苏云金芽胞杆菌NBIV-330可湿性粉剂的研究与应用

湖北省生物农药工程研究中心针对抗性小菜蛾筛选获得高毒力菌株苏云金芽胞杆菌（NBIV-330），制备出50000 IU/mg苏云金芽胞杆菌NBIV-330可湿性粉剂。该产品用于防治抗性小菜蛾，每亩用量30～50 g，药后3 d防治效果达到85%以上。     

防治番茄灰霉病的枯草芽胞杆菌BAB-1粉尘剂研制

目前我国农药登记的微生物杀菌剂主要为水剂和可湿性粉剂两种剂型。为了克服常规喷雾导致温室大棚内湿度增加给防病带来的不利影响,本文以枯草芽胞杆菌BAB-1为有效成分开展了粉尘剂研究,通过对载体和助剂的筛选,明确了最佳的载体、助剂种类及其比例,最终确定100亿CFU/g枯草芽胞杆菌BAB-1粉尘剂的配方为：滑石粉20%、分散剂GY-D900 2%、菌株BAB-1原药补足至100%。该制剂具有很好的悬浮效果（30 min时悬浮率>50%）。室内盆栽试验表明,菌株BAB-1粉尘剂对番茄灰霉病防效达到57.14%~71.43%,对黄瓜灰霉病的保护作用优于治疗作用,施用1次的防病效果分别为48.80%和1.65%;温室大棚试验结果表明,该制剂在番茄大棚中施用3次后对灰霉病的防效达到79.04%,对照化学药剂嘧菌酯800倍水溶液的防效为82.55%。该研究结果为枯草芽胞杆菌BAB-1粉尘剂的进一步产业化开发和应用提供了科学依据。     

内生短短芽胞杆菌011可湿性粉剂的研制

以植物内生短短芽胞杆菌011为研究对象,通过对载体、润湿剂、分散剂、稳定剂、保护剂的筛选,确定了内生短短芽胞杆菌011可湿性粉剂最佳配方：滑石粉10%,木质素磺酸钙7%,DBS 3%,CMC-Na 2%,糊精0.1%。结果显示制备的短短芽胞杆菌011可湿性粉剂在25 ℃室温下芽胞含量为1. 8×1010 cfu/g,pH 6.8,悬浮率76%,润湿时间52s,细度通过率98%。能有效降低化学农药在农业生产中的使用率,减少农药对生态环境的破坏。     

Rearing the honeydew moth,Cryptoblabes gnidiella,and the effect of diflubenzuron on its eggs

The rearing of the honeydew moth,Cryptoblabes gnidiella Mill., is described. The toxicity at 27° and 22° C of diflubenzuron against eggs ofC. gnidiella was assayed by dipping in aqueous dilutions of a 5% liquid experimental formulation and of a 25% wettable powder (w.p.). The w.p. was more active than the liquid formulation, and toxicity at 27° was higher than at 22°C, for both formulations. The LC-50s of the w.p. were 0.00025 and 0.006%, and of the liquid formulation 0.009 and 0.095 a.i., at 27° and 22°C, respectively; the LC-90s of the w.p. were 0.0033 and 0.037%, and of the liquid formulation 0.36 and 2.5% a.i., at 27° and 22° C, respectively.