Assessment of the effects of crop injury by blackcurrant leaf midge,Dasineura tetensi (Rübsaamen) (Cecidomyiidae) on yield and growth in commercial blackcurrant plantations

Sex pheromone trap catches, galling damage, yield and growth were recorded over up to three successive seasons (2010–2012) in large replicated plots treated versus untreated with synthetic pyrethroid (SP) insecticides for blackcurrant leaf midge Dasineura tetensi control in eight established commercial blackcurrant plantations in southern England. The aim was to determine whether or not the current practice of spraying insecticides against the pest in commercial fruiting plantations is justified. In two separate small plot replicated experiments (in 2010 and 2011, respectively) in plantations which had been cut down in the previous winter, galling damage and shoot growth were recorded in the vigorous regrowth in plots treated versus untreated with SP insecticides against 1st, 2nd or both D. tetensi generations. Cutting down bushes to ground level in this way is a common way of regenerating plantations.In the experiments in the established fruiting plantations, applying sprays of insecticides led to substantial reductions in numbers of adult D. tetensi caught in sex pheromone traps (by 72% on average) and reductions in galling damage (by 75% on average) but did not result in increases in yield or statistically significant increases in shoot growth. Multiple possible mechanisms of yield compensation are discussed. In the experiments in the cut-down bushes where the galling was intense, the D. tetensi damage resulted in severe (59%) stunting and multiple branching of the regrowth which was weak and thin. Sprays against the 2nd generation only partially reduced stunting (to 24%).The results of this work call into question the current commercial practice of controlling this pest in established commercial plantations with sprays of insecticides: as significant increases in yield or growth did not result in these experiments, the effects of the sprays was largely cosmetic. Further, broad spectrum synthetic pyrethroid insecticides are likely to have persistent adverse effects on the natural enemies of D. tetensi. However, the work showed that control in re-growing cut-down plantations, and by analogy in young establishing plantations, is vital, as well as the value of the D. tetensi sex pheromone traps for timing sprays of insecticides.     

2.5%三氟氯氰菊酯微胶囊剂防治菜青虫田间药效试验

为验证2.5%三氟氯氰菊酯微胶囊剂对菜青虫的防治效果,设计了2.5%三氟氯氰菊酯微胶囊剂3个不同剂量与2.5%三氟氯氰菊酯乳油及清水对照试验。结果表明：2.5%三氟氯氰菊酯微胶囊剂对菜青虫具有较好的防治效果,优于对照药剂2.5%三氟氯氰菊酯乳油,并且持效期较长,是值得推广的一种高效低毒杀虫剂。     

氯氰菊酯和三氟氯氰菊酯酶联免疫检测方法的建立

利用自制抗体建立并优化了氯氰菊酯和三氟氯氰菊酯的间接竞争ELISA(IC-ELISA)检测方法.结果显示,抗体对免疫原的I50为0.048 μg/ml;IC-ELISA分析检测中,有机溶剂丙酮浓度应小于5%;抗体对氯氰菊酯、三氟氯氰菊酯的I50分别为1.155 3 μg/ml 和 1.709 5 μg/ml,I10分别为 0.011 7 μg/ml 和 0.048 5 μg/ml.     

海南豇豆蚜对敌敌畏、三氟氯氰菊酯、辛硫磷和氰戊菊酯的敏感性测定

就海南省崖城、金江、通什和两院地区豇豆上的豇豆蚜对敌敌畏、三氟氯氰菊酯、辛硫磷和氰戊菊酯的敏感性进行了初步调查与研究。试验结果表明，不同地区豇豆蚜对敌敌畏、三氟氯氰菊酯、辛硫磷和氰戊菊酯的敏感性存在明显差异。崖城和金江两地区豇豆蚜种群对三氟氯氰菊酯、辛硫磷、氰戊菊酯和DDV均表现出较强的抗药性。以两院地区豇豆蚜作为敏感品系，崖城和金江两地区豇豆蚜种群对三氟氯氰菊酯、辛硫磷、氰戊菊酯、DDV的LC50抗性比值分别为21.86倍、22.78倍、17.88倍、13.49倍和10.91倍、12.59倍、11.47倍和13.49倍。通什地区的豇豆蚜对三氟氯氰菊酯、辛硫磷、氰戊菊酯和DDV的抗性也有一定的提高，与两院种群LC50抗性比值分别为1.58倍、12.27倍、4.45倍和2.28倍。而且崖城、金江和通什地区豇豆蚜种群对三氟氯氰菊酯、辛硫磷、氰戊菊酯和DDV抗性种群的异质性很强。     

两种菊酯类农药对鲤血细胞的影响

采用对鲤肌肉注射不同浓度的高效反式氯氰菊酯和功夫菊酯,研究了两种菊酯类农药对鲤血细胞形态、红细胞渗透脆性的影响。结果显示:随两种农药攻毒浓度增大、时间延长,鲤血细胞异形率增大。低浓度(6、60μg/kg)中毒鲤成熟红细胞大小不一,核稍有畸形,淋巴细胞、单核细胞增多,核浆界限不清,有空泡,甚至伴有核溶解的白细胞;而高浓度(600、6 000μg/kg)中毒鲤血细胞中除伴有低浓度中毒症状,还出现了染色质模糊,部分白细胞核浆界限不清,甚至溶解,退化更明显。红细胞渗透脆性亦随攻毒浓度增大、时间延长而增高,且开始溶血点的变化幅度较完全溶血点大,表明最小抵抗值更易受环境因子影响。     

Resistance of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), larvae in Michigan to insecticides with different modes of action and the impact on field residual activity

BACKGROUND: The codling moth is one of the principal pests of apple in the world. Resistance monitoring is crucial to the effective management of resistance in codling moth. Three populations of codling moth in neonate larvae were evaluated for resistance to seven insecticides via diet bioassays, and compared with a susceptible population. In addition, apple plots were treated with labeled field rate doses of four insecticides. Treated fruit were exposed to neonate larvae of two populations from commercial orchards. RESULTS: Two populations of codling moth expressed two‐ and fivefold resistance to azinphos‐methyl, seven‐ and eightfold resistance to phosmet, six‐ and tenfold resistance to lambda‐cyhalothrin, 14‐ and 16‐fold resistance to methoxyfenozide and sixfold resistance to indoxacarb, but no resistance to acetamiprid and spinosad. The impact of the resistance to azinphos‐methyl, measured as fruit damage, increased as the insecticide residues aged in the field. In contrast, fruit damage in methoxyfenozide‐ and lambda‐cyhalothrin‐treated fruit was observed earlier for resistant codling moth. No differences in efficacy were found for acetamiprid. CONCLUSIONS: Broad‐spectrum insecticide resistance was detected for codling moth. Resistance to azinphos‐methyl, lambda‐cyhalothrin and methoxyfenozide was associated with reduced residual activity in the field. Broad‐spectrum resistance presents serious problems for management of the codling moth in Michigan. Copyright © 2008 Society of Chemical Industry     

抗三氟氯氰菊酯棉铃虫种群相对适合度研究

应用经三氟氯氰菊酯汰选的棉铃虫种群,在室内条件下分别研究了抗性、敏感及杂交Ｆ_１代（ＲＳ和ＳＲ）基因型相对适合度。结果表明,抗性基因型在产卵量、卵孵化率、幼虫及蛹历期和成虫存活期等方面与敏感基因型相比较存在明显的不利性;与敏感基因型相比,抗性基因型只有０.４５的适合度,ＲＳ和ＳＲ基因型的相对适合度分别为１.１４和１.０８。     

单对汰选方法在加速抗高效氯氟氰菊酯棉铃虫品系汰选中的应用

通过设计杂合种群单对杂交方式,研究了加速获得抗性品系的方法。以高效氯氟氰菊酯群体汰选后抗性倍数为4.9倍的棉铃虫种群及其同源对照种群为材料,同时设置常规群体汰选方法与单对汰选方法,研究单对汰选方法在加速抗高效氯氟氰菊酯棉铃虫品系汰选中的作用。结果表明,群体汰选两代后抗性倍数由4.9倍提高到7.4倍, 而单对汰选两代后抗性倍数由4.9倍提高到27.3倍。表明在常规群体汰选中穿插几代单对汰选方法可明显加快棉铃虫种群对高效氯氟氰菊酯的抗性汰选进程。     

Control of air-borne field spread of tulip breaking virus,lily symptomless virus and lily virus X in lilies by mineral oils,synthetic pyrethroids,and a nematicide in the Netherlands

The inhibitory effect on the spread of viruses in lilies viz., tulip breaking virus (TBV; nonpersistently aphid-borne, potyvirus,) lily symptomless virus (LSV; non-persistently alphidborne, carlavirus), and lily virus X (LVX; potexvirus of unknown etiology), was studied of brands of mineral oil (Luxan oil H and Duphar-7E oil) and synthetic pyrethroid insecticides (l-cyhalothrin and deltamethrin), and a nematicide (aldicarb) in crops in which virus-infected plants were present as virus sources. The spread of TBV and LSV were controlled by sprays of mineral oil and insecticide, while that of LSV was also limited by the soil-applied nematicide. The spread of LVX was reduced by the insecticides and, not effectively by the mineral-oil spraying, by which data the mode of transmission may be presumed to be by an insect in the persistent or semi-persistent manner.Mixtures of mineral oil and pyrethroid were more effective in the reduction of spread of TBV and LSV than either components tested alone. The mineral oil was the most effective component in the mixtures in which pyrethroid added a slight extra effect. The addition of pyrethroid did not mask either the lower efficacy of the oil brand Duphar-7E oil, or the diminished inhibitory effect of low dosages of oil. The normal rate of mineral oil gave similar control to that of a mixture of mineral oil at half rate plus the pyrethroid at full dosage. Low rates of oil, or even synthetic pyrethroids alone may be used on cultivars which suffer of the loss of bulb weight by the use of normal or decreased rates of oil. Weekly sprays were more effective than fortnightly sprays. The rate of control by the weekly sprays ranged between 90 and 95% for Luxan oil H at half dosage plus the full rate of pyrethroid. Weekly sprayed synthetic pyrethroids alone onto the virus sources and the plants to be infected gave 60–70% control. The weight ratios tended to be slightly reduced if the half dosage of the efficient Luxan oil H was used. Factors which affect the control of the air-borne field spread of viruses by mineral oils and synthetic pyrethroid insecticides in lilies are discussed.     

华北棉区棉铃虫对三种杀虫剂的抗性监测

为明确华北棉区棉铃虫Helicoverpa armigera田间种群对3种常用杀虫剂的抗性,于2014—2015年和2018—2019年分别采集河南、河北、山东和山西4个省的棉铃虫田间种群,采用浸叶法于室内测定棉铃虫对辛硫磷、三氟氯氰菊酯和甲维盐的抗性水平。结果表明,各监测点棉铃虫对辛硫磷处于中等水平抗性,在2014—2015年和2018—2019年的抗性倍数分别为13.0~58.5倍和21.1~55.3倍,棉铃虫对辛硫磷的抗性发展相对缓慢;各监测点棉铃虫种群对三氟氯氰菊酯已产生中等至高水平抗性,并呈现逐年上升的趋势,其中河北沧县、河南安阳、山西盐湖种群的抗性倍数由2014年的61.0倍、22.5倍和24.0倍上升至2019年的91.1倍、44.7倍和61.3倍,山东夏津种群的抗性最高,2019年抗性倍数达到216.3倍;棉铃虫种群对甲维盐表现为低至中等水平抗性,河北沧县、河南安阳、山西盐湖和山东夏津种群的抗性倍数分别为8.2~40.4倍、5.8~16.6倍、5.5~23.4倍和11.0~36.6倍。表明4个监测地区的棉铃虫田间种群对3种杀虫剂已经产生了不同程度的抗性,建议减少这3种杀虫剂的使用频次,并注意与其他杀虫剂交替轮换使用,以延缓棉铃虫抗药性的发展。