高效新型杀松材线虫剂的筛选及其林间防效

为筛选出新型的高效松材线虫Bursaphelenchus xylophilus防治药剂,采用浸渍法室内测定了氯氟氰虫酰胺、阿维菌素、甲维盐、灭多威、特丁硫磷、甲基异柳磷和吡虫啉7种药剂对松材线虫的毒杀作用和对其繁殖能力的影响,采用高效液相色谱仪测定氯氟氰虫酰胺在马尾松体内的输导分布,并在林间开展树干注射氯氟氰虫酰胺抗松材线虫病试验。结果表明,7种药剂中氯氟氰虫酰胺对松材线虫的毒力最强,LC_(50)为0.019 mg/L,阿维菌素和甲维盐次之,LC_(50)分别为0.0213 mg/L和0.0214 mg/L。氯氟氰虫酰胺树干注射3个月内能迅速从马尾松基部传导至树梢顶部,树干边材东、南面的药剂含量显著高于西、北面,且树干不同高度的氯氟氰虫酰胺含量均高于其LC50;氯氟氰虫酰胺制剂在林间注干后,对人工接种病原松材线虫松树的防治效果为73.33%,自然感染松材线虫病松树的死亡率降至2.00%,而对照试验中人工接种松材线虫松树和自然感染松材线虫病松树的死亡率分别为93.33%和19.67%。表明氯氟氰虫酰胺制剂能有效预防松树个体的松材线虫病发生与为害,可以推广使用。     

注干施用甲维盐防治松材线虫病的研究

以树干注射方式对黑松基部按地径施用不同剂量的甲维盐,利用高效液相色谱法测定注药90d后和2年后树体内甲维盐含量;在林间注药黑松上人工接种松材线虫,调查防治松材线虫病的效果.结果表明,注药90 d后,按松树地径2 mL/cm注药量的甲维盐可输导至树体注干点以上不同部位至枝干顶梢,注药2年后,在注干点以上不同部位仍能检测出...     

松材线虫病综合防控试验研究

为有效指导林木病害防控工作，在武汉市马鞍山森林公园和湖北崇阳进行了松材线虫的病虫害防治试验。结果表明，通过病枯死树清理、打孔注药、设置引诱木与花绒寄甲释放等综合防控措施，成功压制了病死树数量的上升势头，2017～2020年防控期间的病死树数量总减退率达到99.55%,逐年下降率均达到56%以上，主要媒介昆虫松褐天牛总减退率达到99.41%。花绒寄甲释放对松褐天牛的平均寄生率为39.87%,松褐天牛平均虫口减退率为48.31%,平均防效为43.14%。通过有效遏制媒介害虫松褐天牛的发生能有效防治松材线虫病，同时对其它蛀干害虫褐梗天牛及松瘤象也有较好的防控效果。     

辽宁省松材线虫病疫木上发现媒介天牛的天敌花绒寄甲

花绒寄甲作为天牛类害虫的重要天敌在我国广泛应用于生物防治，尤其在控制松材线虫最重要的传播媒介松褐天牛方面发挥了重要作用，它在自然界与不同种类的天牛长期协同进化，形成了不同生物型。本文在辽宁省抚顺松材线虫病疫区的疫木上调查发现了花绒寄甲越冬成虫，通过形态学和生物学观察，确定了该花绒寄甲为云杉花墨天牛生物型花绒寄甲。这是花绒寄甲作为云杉花墨天牛的自然天敌在我国首次被发现，这将对中国北方地区松材线虫病传播媒介的防治起到积极的推动作用。     

甲维盐单剂及复配剂对草地贪夜蛾的防效

为筛选草地贪夜蛾应急防控药剂,选择甲维盐单剂及复配制剂,设置常量和减量施用处理,进行玉米田药效验证。结果表明,药后3、7、10 d,各施药处理均表现出一定的防效,其中,复配剂25%甲维·茚虫威水分散粒剂、5%高氯·甲维盐微乳剂常量处理的防效接近或显著高于甲维盐单剂;12%甲维·氟酰胺微乳剂+激健、6%阿维·氯苯酰悬浮剂+15%茚虫威乳油两减量(较常规用量减少20%)处理在药后3 d防效稍差,药后7 d防效分别升至94.71%、87.07%,药后10 d防效均达到95%以上。各药剂施用10 d后,相应处理区草地贪夜蛾幼虫存量减少,玉米最初受害状大程度得以恢复。     

马尾松(Pinus massoniana)感染松材线虫(Bursaphelenchus xylophilus)的研究

 1987-1988年在江苏南京-镇江松材线虫疫区内采(征)集143份自然枯死或濒死马尾松样本,在94份(65.7%)样本中查见松材线虫。有关林分中马尾松的病枯情况不一,在句容桥头一下蜀一线、江宁汤山和六合方山等处有过相当多的马尾松发病死亡。表明松材线虫是当地马尾松自然枯死的主要原因。人工测定了无黑松林区5年生浙江富阳马尾松苗及混栽黑松林区4-5年生江苏马尾松苗对两种松材线虫分离物的反应,结果指出,供试松苗都表现中度感染或高度感染,并有20%或70-80%的病枯株。接种林间马尾松,初步证实马尾松对松材线虫的抗性随树龄变化。1-2年生马尾松苗高感松材线虫,病枯株率高达85.7%;树龄25年以上的成材树病枯株率约30%;而10年左右的幼树则无一发病死亡。     

氯氟氰虫酰胺注干剂在松树体内的残留动态

[目的]为探明氯氟氰虫酰胺注干剂在松树体内的持效时间.[方法]采用高效液相色谱法测定不同时期松树体内氯氟氰虫酰胺的含量.[结果]注干施药后5～120 d均可从样树的枝条中检测到氯氟氰虫酰胺,注药剂量为10 mL时药后15 d含量达到高峰,为16.54 mg/kg,药后120 d含量为1.24 mg/kg.[结论]松树注药5～120 d内枝条上氯氟氰虫酰胺药液浓度均高于其对松材线虫的LC50值而对松材线虫和松褐天牛等有防治抑制作用.     

释放花绒寄甲和设置诱木防治松褐天牛对松材线虫病的控制作用研究

松材线虫是我国林业重大外来有害生物,松褐天牛是传播松材线虫病的主要媒介昆虫。本研究通过在松材线虫病疫区布设诱木引诱松褐天牛成虫集中产卵,翌年在下一代松褐天牛成虫羽化出孔前清理林中诱木和枯死木,以及在诱木布设区同时释放寄生性天敌花绒寄甲等措施,探讨对松材线虫病的控制作用。研究结果显示,林间设置诱木和释放天敌的样地内枯死木和衰弱木数量较对照显著下降,防治效果分别为71．27％和90．25％。防治后诱木处理区和释放天敌的样地内携带松材线虫的病木数量以及松褐天牛的虫口密度也显著降低。释放天敌的样地和未释放天敌的样地内松褐天牛的寄生率分别为38．34％和3．92％,二者差异明显。室内人工接种天敌的测定结果表明,天敌与害虫数量比例为1：1～4：1的寄生率为12．5％～40％,不同比例的处理寄生率无显著差异。每根木段释放10头花绒寄甲成虫比释放4头成虫的处理松褐天牛的寄生率明显要高,分别为19．45％和4．11％。表明天敌在林间对松褐天牛种群起到重要的控制作用,从而阻止天牛对松材线虫病的扩散传播。     

甲维盐·氯虫苯甲酰胺组合物对草地贪夜蛾室内毒力测定及田间防治效果

为筛选出甲维盐与氯虫苯甲酰胺复配防治草地贪夜蛾的最佳配比,采用浸虫法测定了甲维盐、氯虫苯甲酰胺及组合物对草地贪夜蛾的室内毒力,并基于最佳增效配比进行了田间防治效果评价试验。结果表明,甲维盐和氯虫苯甲酰胺复配组合在二者质量比介于2∶8～7∶3范围内表现增效作用,以3∶7时增效作用最大,共毒系数CTC为173。基于该比例加工获得10%甲维盐·氯虫苯甲酰胺水分散粒剂,并以此开展田间防治草地贪夜蛾效果评价,结果表明,施药浓度高于有效剂量37.5 g/hm~2时,药后3、14 d对草地贪夜蛾的防效分别达到88%和84%以上,表现出良好的速效性和持效性。甲维盐和氯虫苯甲酰胺以质量比3∶7混配是防治草地贪夜蛾的良好配方。     

园林树木种类及树冠大小对自流式注干药剂吸收及传导的影响

为探明园林树木种类、树冠大小及药剂种类对自流式注干药剂吸收及传导的影响,将甲氨基阿维菌素苯甲酸盐（简称甲维盐）分别与丁硫克百威、吡虫啉及阿维菌素组合,配制成2.8%甲维盐＋0.3%丁硫克百威（简称3.1% EB）、6%甲维盐＋4%吡虫啉（10%EB）与2%甲维盐＋0.5%阿维菌素（2.5% EB）3种乳油（EC）注干液剂,通过自流式树干注药方式,将3.1% EB和10% EB分别导入香抛树、柳树与栾树体内,研究了不同树种及不同药剂下药液吸收与传导的差异;采用2.5% EB,研究了香抛树树冠直径对药液吸收及传导的影响,同时通过HPLC-UVD检测方法,考察了药剂的残效期。结果表明:树木种类会显著影响注干药剂的吸收,且吸收速率依次为柳树>香抛树>栾树,开始注药5 d后,柳树上的药剂已被全部吸收,而栾树上3.1% EB和10% EB 的剩余量分别为66.6% 和48.6%;开始注药5 d后,10% EB在香抛树上的吸收率显著高于3.1% EB,两者剩余量分别为12.6%和29.3%,而其他处理则显示药剂种类对其吸收率影响不大;香抛树树冠直径大小对2.5% EB的吸收具有显著影响,冠径越大越利于药剂的吸收;开始注药起第113天,在香抛树枝叶中仍能检测到阿维菌素和甲维盐残留。研究表明,柳树对3.1% EB和10% EB的吸收性能均最佳,且供试药剂种类对其吸收性能影响不大;香抛树冠径大小与其对2.5% EB的吸收呈正相关性,且药剂残效期高达90~120 d。     

烷基糖苷和单烷基磷酸酯钾盐在3%甲氨基阿维菌素苯甲酸盐微乳剂中的应用及其环境安全性

为探讨绿色表面活性剂烷基糖苷(APG)和单烷基磷酸酯钾盐(MAPK)在3%甲氨基阿维菌素苯甲酸盐(简称甲维盐)微乳剂中的应用,以传统表面活性剂辛基酚聚氧乙烯醚(OP-10)和壬基酚聚氧乙烯醚磷酸酯(NP-10P)作对照,在运用拟三元相图法确定最佳复配比例的基础上,比较了MAPK/APG复配体系和NP-10P/OP-10复配体系对甲维盐的增溶作用;在表面活性剂总质量分数为10%及最佳复配比例下,分别采用2种表面活性剂复配体系制备了技术质量指标符合标准的3%甲维盐微乳剂,并测定了其对小菜蛾 Plutella xylostella 的生物活性;就绿色表面活性剂和传统表面活性剂对环境的安全性(对水生生物的安全性和生物降解性)进行了比较。结果表明:在最佳复配比例下,MAPK/APG[m(MAPK) :m(APG)=2 :1]的表面活性及对甲维盐的增溶能力均低于NP-10P/OP-10[m(NP-10P) :m(OP-10)=1 :2];用2种表面活性剂复配体系制备的微乳剂对小菜蛾的生物活性无明显差异;4种表面活性剂对斑马鱼和大型溞的毒性趋势相似——APG毒性最小,MAPK和NP-10P的毒性相当,OP-10毒性最大;28 d后APG、MAPK、NP-10P和OP-10的生物降解率分别为61.5%、49.7%、17.9%和15.0%,MAPK和APG的生物降解率明显高于NP-10P和OP-10。表明绿色表面活性剂APG和MAPK在农药制剂领域具有较好的开发应用前景。     

Development of a water-soluble preparation of emamectin benzoate and its preventative effect against the wilting of pot-grown pine trees inoculated with the pine wood nematode, Bursaphelenchus xylophilus

Water-soluble preparations have been investigated to develop a trunk injection agent based on the poorly water-soluble anti-nematode emamectin benzoate. Following tests on the phytotoxicity of some solvents and solubilizers and demonstration of the ability of some solubilizers to dissolve emamectin benzoate in water, acetone + methanol was selected as the solvent and Polysorbate 80 as the solubilizer. This water-soluble preparation of emamectin benzoate prevented the wilting of pot-grown 4-year-old trees of the Japanese black pine, Pinus thunbergii, artificially inoculated with the pine wood nematode, Bursaphelenchus xylophilus, at a dose of 20 g emamectin benzoate per cubic metre of pine tree.     

Distribution and persistence of emamectin benzoate at efficacious concentrations in pine tissues after injection of a liquid formulation

In an earlier paper the authors reported the creation of a novel emamectin benzoate 40 g litre(-1) liquid formulation (Shot Wan Liquid Formulation). The injection of this formulation exerted a preventative effect against the pine wilt disease caused by the pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and this effect lasted for at least 3 years. The present study was carried out to show experimentally that the marked effect of this formulation was due to the presence and persistence in pine tissues of sufficient amounts of emamectin benzoate to inhibit nematode propagation. A cleanup procedure prior to quantitative analysis of emamectin benzoate by fluorescence HPLC was devised. The presence of the compound in concentrations sufficient to inhibit nematode propagation in the shoots of current growth and its persistence for 3 years explained the marked preventative effect. Non-distribution of emamectin benzoate in some parts of the lower trunk suggested that the formulation should be injected at several points for large trees in order to distribute the compound uniformly to lower branches.     

Prevention of pine wilt disease induced by Bursaphelenchus xylophilus and Monochamus galloprovincialis by trunk injection of emamectin benzoate

The pine wood nematode Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle is the causal agent of pine wilt disease. We evaluated the efficacy of emamectin benzoate (EB) for preventing wilt disease in the field and its effect on the vector Monochamus galloprovincialis (Olivier) (Coleoptera: Cerambycidae). Four experimental plots were delimited in a maritime pine (Pinus pinaster Aiton) forest in Portugal. Trunk-injection trials with EB included three dose-rates: 0.032 g a.i. cm^?1 diameter at breast height—DBH, n?=?75 trees; 0.064 g a.i. cm^?1 DBH, n?=?75 trees; and 0.128 g a.i. cm^?1 DBH, n?=?50 trees; along with an untreated control plot (n?=?75 trees). EB was successfully injected and translocated in pines at an effective concentration. None of the treated trees died after a period of 26 months, contrasting with a 33% mortality of non-treated pines. Analysis of residues successfully detected EB in branches of treated pines, with the quantity increasing relative to the injection dose rate, and was found to have a clear effect on the longevity and feeding activity of adult M. galloprovincialis feeding on branches. EB was efficient in preventing wilt disease and bark beetle attacks in the terrain, and its application by trunk injection is a new option for wilt disease management programs in Portugal and in Europe.     

Development and preventative effect against pine wilt disease of a novel liquid formulation of emamectin benzoate

Injection of the poorly water-soluble emamectin benzoate (EB) into pine trunks required the development of an efficient liquid formulation. For injection into big trees in forests a good rate of injection and a high active content were required. Tests on the viscosity and EB-solubilizing ability of 14 various solubilizers in diethylene glycol monobutyl ether (DGMBE) led to the selection of Sorpol SM-100PM as the solubilizer of the formulation. Relationships between the solubilizing ability and amounts of Sorpol SM-100PM and DGMBE relative to that of EB, and between the concentration of the latter and the viscosity or the injection rate of the formulation led to a novel 40 g litre(-1) emamectin benzoate formulation (Shot Wan Liquid Formulation), which was composed of EB (40), Sorpol SM-100PM (120), DGMBE (160) and distilled water (50 g litre(-1)) in methanol. Injection of this formulation at a dose of 10 g EB per unit volume of pine tree prevented over 90% of the trees from wilting caused by pine wood nematode, and this preventative effect continued for 3 years. Neither discolouration of the leaves nor injury around the injection hole on the trees was observed after injection of the formulation.     

粘虫抗甲氨基阿维菌素苯甲酸盐种群的交互抗性与生化抗性机制

为指导甲氨基阿维菌素苯甲酸盐（下称甲维盐）在粘虫Mythimna separate Walker防治上的合理使用,测定了粘虫抗甲维盐种群对5种常用杀虫剂的交互抗性及其生化抗性机制。结果表明:粘虫抗甲维盐种群对阿维菌素（抗性倍数RR₅₀=21.80）、毒死蜱（RR₅₀=17.68）和灭多威（RR₅₀=10.85）均具有中等水平的交互抗性,与辛硫磷（RR₅₀=6.00）和氟氯氰菊酯（RR₅₀=5.65）之间交互抗性水平较低。酶抑制剂胡椒基丁醚（PBO）、马来酸二乙酯（DEM）、三丁基三硫磷酸酯（DEF）和磷酸三苯酯（TPP）在粘虫敏感种群和抗性种群生物测定中对甲维盐毒力均有显著的增效作用。粘虫抗甲维盐种群细胞色素P450和b₅含量及O-脱甲基酶、谷胱甘肽S-转移酶和羧酸酯酶活性均显著高于敏感种群,分别为敏感种群的3.23、3.65、3.63、1.64和2.66倍。研究表明,体内解毒代谢酶活性提高可能是粘虫对甲维盐产生抗性的重要原因。     

松脂二烯在植物叶片表面的成膜性能

为明确松脂二烯 (pinolene) 提高农药田间防效的机理,研究了其在植物叶片表面的成膜性能。以红叶石楠和山核桃为试材,分别将3%噻虫啉微囊悬浮剂和2%甲氨基阿维菌素苯甲酸盐微乳剂与松脂二烯桶混后喷施到植物叶片上,通过电镜及光合测定仪,观测了松脂二烯对农药药液在叶片表面的成膜形态及其对光合作用的影响;通过人工模拟降雨和氙灯光照,研究了松脂二烯抗雨水冲刷能力和抗光解能力。结果表明:添加松脂二烯的农药颗粒表面均有一层明显的油状包被。在不同雨水冲刷时间段,添加松脂二烯的噻虫啉处理组植物叶片上的农药保持量均显著高于对照组;松脂二烯和甲氨基阿维菌素苯甲酸盐混用,能显著降低甲氨基阿维菌素苯甲酸盐的光分解速率;松脂二烯叶片成膜致其光合速率下降5.16%,但与对照无显著差异。本研究结果表明,松脂二烯和农药混用,可增加农药有效成分在植物叶片上的成膜性,且对植物光合作用影响较小,可有效减少农药受雨水冲刷损失和光解速率,延长农药持效期。     

Toxicity of emamectin benzoate to Cydia pomonella (L.) and Cydia molesta (Busck) (Lepidoptera: Tortricidae): laboratory and field tests

BACKGROUND: Emamectin benzoate is a novel macrocyclic lactone insecticide derived from naturally occurring avermectin molecules isolated by fermentation from the soil microorganism Streptomyces avermitilis Kim & Goodfellow. The present study aims to evaluate the toxicity of emamectin benzoate to codling moth, Cydia pomonella (L.), and oriental fruit moth, C. molesta (Busck), under laboratory and semi‐field conditions. RESULTS: Dose response bioassays showed that emamectin benzoate had a high level of intrinsic toxicity to early‐stage larvae of both species, and that contact activity might contribute significantly to mortality. In the semi‐field trials, residual toxicity lasted for more than 1 week. Ovicidal activity was recorded only for C. pomonella (approximately 30%), irrespective of the concentrations tested. Field trials confirmed the efficacy of emamectin benzoate on codling moth when applied at 7 day intervals. Fruit damage, both from the first and second generations, was comparable with that on treatment with chlorpyrifos‐ethyl, used as a chemical reference. CONCLUSION: Emamectin benzoate may be considered a valuable tool for the control of codling moth as a component of an IPM programme. Its collective advantages are: high efficacy, lack of cross‐resistance with currently used products, control of secondary pests such as oriental fruit moth and selective toxicity that spares beneficials. Copyright © 2008 Society of Chemical Industry