Comparing the impact of conventional pesticide and use of a transgenic pest-resistant crop on the beneficial carabid beetle Pterostichus melanarius

The potential impact of a chemical pesticide control method has been compared with that of transgenic plants expressing a protease inhibitor conferring insect resistance by utilising a tritrophic system comprising the crop plant Brassica napus (L.) (Oilseed rape), the pest mollusc Deroceras reticulatum (Müller) and the predatory carabid beetle Pterostichus melanarius (Illiger). Cypermethrin, as the most widely used pesticide in UK oilseed rape (OSR) cultivation, was selected as the conventional treatment. OSR expressing a cysteine protease inhibitor, oryzacystatin-1 (OC-1), was the transgenic comparator. In feeding trials, D. reticulatum showed no significant long-term effects on measured life history parameters (survival, weight gain, food consumption) as a result of exposure to either the cypermethrin or OC-1 treatment. However, D. reticulatum was able to respond to the presence of the dietary inhibitor by producing two novel proteases following exposure to OC-1-expressing OSR. Similarly, P. melanarius showed no detectable alterations in mortality, weight gain or food consumption when feeding on D. reticulatum previously fed either pesticide-contaminated or GM plant material. Furthermore, as with the slug, a novel form of protease, approximately M(r) 27 kDa, was induced in the carabid in response to feeding on slugs fed OC-1-expressing OSR.     

Effects of a neem-based insecticide on different immature life stages of the leafminerLiriomyza sativae on tomato

The effects of the commercially available neem insecticide NeemAzal-T/S® (neem) (1% azadirachtin) onLiriomyza sativae (Diptera: Agromyzidae) were studied on tomato in Bangkok, Thailand. Neem emulsions were sprayed on the aerial plant parts at five concentrations (from 0.001% to 0.010% a.i.); different aged residues (0, 1, 3, 5, and 7 days) were tested, in both controlled environment rooms and in greenhouses. Irrespective of the residual age of the application, no significant effects on oviposition or egg hatch were detected. However, neem drastically increased larval mortality at the higher concentrations tested. The L1 and L2 larvae were most susceptible. Irrespective of concentration, larval mortality or inhibition of adult eclosion decreased much faster in greenhouses than in controlled environments with artificial light. Nevertheless, our results suggest that neem has potential to controlL. sativae in netted greenhouses.     

A review of research to address carrot fly (Psila rosae) control in the UK1

Carrot fly (Psila rosae) is a serious pest of umbelliferous crops such as carrot, parsnip, celery and parsley. Carrot fly has been studied in the UK for more than 60 years. Whilst some of these studies have been focused on insecticides, others have demonstrated the potential for non‐insecticidal methods of control that might contribute to an integrated pest management strategy. These include rotation and spatial separation of susceptible crops; carrot varieties with partial resistance to carrot fly; and crop management strategies to avoid oviposition or the development of severe damage. This paper outlines some of the approaches that have been taken and indicates how these are, or might be, used in practice.     

Selectivity of chlorantraniliprole to parasitoid wasps

BACKGROUND: Chlorantraniliprole is a novel anthranilic diamide insecticide registered for use in vegetables, fruits, grains and turf against a variety of insect pests. The objective of this article is to summarize results of acute toxicity testing of chlorantraniliprole on seven species of parasitic wasps with wide geographic distribution and relevance to different crops and integrated pest management (IPM) programmes. RESULTS: Tier‐1, worst‐case laboratory studies evaluated wasp survival and reproduction following different exposure concentrations and scenarios to chlorantraniliprole (i.e. fresh‐dried spray deposits on glass plates, direct contact, ingestion, egg card, dipped leaf residue bioassays, sprayed mummies). No statistically significant effects on adult survival, percentage parasitism or emergence were observed following exposures to chlorantraniliprole compared with controls. CONCLUSION: Chlorantraniliprole was harmless to the parasitoid wasp species tested according to IOBC classification criteria (<30% effects) and may be a useful tool in IPM programmes. Copyright © 2010 Society of Chemical Industry     

Toxicity of botanical insecticides on Diaphania hyalinata,their selectivity for the predatory ant Paratrechina sp., and their potential phytotoxicity on pumpkin

The use of botanical insecticides could be an alternative efficient pest management in Cucurbitaceae against melonworm Diaphania hyalinata and less harmful to its predator. Few studies jointly assess the efficiency of botanical insecticides, their effects on pest, and their effect on the natural enemy and target crop. Here we examine (1) their impact against the melonworm D. hyalinata, a key pest of Cucurbitaceae, (2) their toxicity to the predatory ant Paratrechina sp., and (3) their phytotoxicity to pumpkin plants. The botanical insecticides citronella oil and eucalyptus oil were highly toxic to D. hyalinata and they exhibited to be less harmful for the predatory ant Paratrechina sp. Andiroba oil, eucalyptus oil, garlic extract, and citronella oil caused feeding inhibition of the D. hyalinata larvae. Eucalyptus oil, andiroba oil, garlic extract, and rotenone inhibited the oviposition of D. hyalinata. None of the insecticides was phytotoxic to pumpkin plants. Eucalyptus oil and citronella oil have induced high mortality and altered the behavior of target pests. In addition, they were selective for the predator Paratrechina sp. and not exhibited phytotoxicity on pumpkin plants. Eucalyptus oil and citronella oil seem the most promising compounds for incorporation into melonworm management programs, because they induced high mortality and altered the behavior of target pests and were selective for the predator Paratrechina sp.     

Integrated pest management in protected ornamentals in England1

During the past 2 years, there has been a rapid expansion of integrated pest management (IPM) in the ornamental sector of the glasshouse industry. Most of this expansion has resulted from improved availability of Amblyseius spp. for the control of thrips, although there is little information on the likelihood of success with this predator. IPM was done on 20 plant species on 21 nurseries in south-east England and there were many successes with crops that would normally receive intensive insecticide programmes to control thrips. Each plant species required its own IPM programme to be devised according to its pest complex. Techniques, particularly to monitor IPM, were devised and some staff were trained to assist in the monitoring. IPM is generally twice as expensive as routine insecticide programmes but has other advantages such as a safer environment for staff and better crop quality.     

Attract-and-kill strategy. Laboratory studies on hatched larvae of Culex pipiens

The attract‐and‐kill strategy is a new pest management technique that presupposes the intelligent combination of an attracting agent (e.g. pheromone) and a killing agent (e.g. insecticide). In the present study, the potential combination of the microencapsulated synthetic oviposition pheromone 6‐acetoxy‐5‐hexadecanolide with an insecticide has been tested. Initially, polyurea microcapsules containing 6‐acetoxy‐5‐hexadecanolide, the synthetic mixture of diastereomers of the oviposition pheromone of the mosquito species Culex quinquefasciatus Say (Diptera: Culicidae), were studied. Laboratory bioassays were performed to confirm the bioactivity of the microencapsulated pheromone on the oviposition activity of Culex pipiens L. biotype molestus Førskal (Diptera: Culicidae) with the aim of determining the optimum dose for oviposition response. Its effect was dose dependent, revealing an optimum dose of 300 mg of dried microcapsules. Attractancy over time was also studied. The microencapsulated pheromone was found to be sufficiently attractive to gravid female mosquitoes for a period of 40 days. Finally, the combination of the synthetic pheromone with the control agent temephos showed both an acceptable oviposition activity and sufficient larvicidal effect. Copyright © 2007 Society of Chemical Industry     

Experimental studies on Tuta absoluta (Meyrick) in protected tomato crops in France: biological control and integrated crop protection

Tuta absoluta is a pest from South America which has been detected in many European and Mediterranean countries since 2006. It was identified in Corsica and the South of France in late 2008, and by 2010 this Lepidopteran species had spread to further tomato‐production areas. The pest is present mainly on tomatoes in protected and field crops, and damage on leaves and fruit can be so severe that it can lead to total destruction of the plant. Since 2010, studies have been carried out in experimental insect‐proof glasshouses with artificial infestations of the pest. The objective was to gain better knowledge of this emergent pest and to develop adapted control strategies under the conditions of the South‐East of France. Integrated pest management is widely used on tomato crops in France, and the predator Macrolophus pygmaeus and the parasitoid Trichogramma achaeae were studied, alone and in combination. The possible effect of the concurrent prey Trialeurodes vaporariorum on the impact of the predator on T. absoluta was also studied. The best results were obtained when the two beneficials were released in combination, even in the presence of whiteflies T. vaporariorum.     

Herbicide-resistant genetically modified crop: assessment and management of gene flow

Genetically modified (GM) crops have become a reality in our cropping system. The experiences with GM oilseed rape have shown that gene flow from a GM crop causes genetic contamination of non‐GM crops and natural flora. This review summarizes technically available methods for gene flow assessment and proposes possible management methods. Methods for direct monitoring of gene flow include direct bioassay of plants and detection of phenotypic and molecular genetic markers contained in GM crops. A recent green fluorescent protein (GFP) marker technique can be powerful in monitoring gene flow as GFP inserted into a plant can be observed macroscopically under UV light. Appropriate analysis of data from direct assessment may give more useful information to mitigate gene flow. Observation with direct method provides real‐time data and mathematical‐statistical approaches may enable the long‐term consequence to be predictable. Although an estimated gene flow is less than an acceptable level, gene flow must be maintained as low as possible with a systematic management. The management should be conducted stepwise; selection of gene flow‐proof GM crops in the stage of development, risk assessment and regulation in the registration stage, cultural management, produce handling/transportation and a long‐term monitoring in cropping stage. Promising methods for developing gene flow‐proof GM crops include conferring cleistogamy and chloroplast transformation to mitigate pollen flow, and breeding non‐ or minimum shedding cultivars to mitigate seed dispersal. We strongly suggest that very high expression of a transgene or stacking multiple transgenes in the chloroplast could disturb the function of normal physiology, hence decreased performance of the GM crop. Before the approval of GM crops, proposed GM crops must go through the risk assessment. If the estimated risk of a GM crop exceeds an acceptable level, approval must be suspended. Once a GM crop is allowed for commercial release, additional efforts must follow, such as a continued long‐term monitoring of the impact of GM crop cultivation, crop and herbicide rotations, GM crop‐suited cultural practices, ‘right‐time’ harvest, and all necessary gene flow‐preventive practices. Such a systematic management incorporating various methods for the stages of GM crop utilization will minimize the risk of gene flow.     

Evaluation of food sprays and relay strip crops for enhancing biological control of bollworms and cotton aphids in cotton

Studies were conducted at the Texas Agricultural Experiment Station research farms located at Munday (1996 test) and Chillicothe (1997 test) to evaluate relay strip crops in combination with a food spray to enhance biological control of bollworms, Helicoverpa zea (Boddie), and cotton aphids, Aphis gossypii Glover, in cotton. The relay crops included fall plantings of hairy vetch, Vicia villosa Roth, and canola, Brassica napus L., and a spring planting of grain sorghum, Sorghum bicolor L. Cotton, Gossypium hirsutum L., was planted between the relay crops or was isolated from the relay crops. Treatments within the two cotton systems included an untreated check plot, a plot sprayed with sugar+yeast (food spray) during summer to attract and hold predator insects, a plot sprayed with biological ('soft') insecticides for bollworm and cotton aphid control (Bacillus thuringiensis and pymetrozine, respectively), and a plot sprayed with harsh insecticides for bollworm and cotton aphid control (zeta cypermethrin and dicrotophos or profonofos, respectively). A split-plot experimental design, with three replications, was used where whole plots included relay and isolated cotton systems and subplots were the four food/chemical treatments. Predator numbers were monitored with a vacuum sampler once a week in relay crops and cotton. Bollworms and cotton aphids were monitored visually once a week in cotton during July and August. Total predator numbers were higher in cotton adjacent to relay crops in 1996, but not in 1997. The food spray did not enhance attraction and retention of predators either year. Bollworm larval numbers were significantly higher in relay cotton, food spray plots in 1996. Bollworm larval numbers were similar in relay and isolated cotton, and larval numbers were significantly reduced only in the plot where zeta cypermethrin (harsh insecticide plot) was used. In 1996, cotton aphid numbers in the relay cotton system were significantly higher in the untreated check plots in relation to numbers in the food spray, soft insecticide, and harsh insecticide plots, which were statistically similar. In the isolated cotton system, aphid numbers were highest in untreated plots, intermediate in food spray and soft insecticide plots, and lowest in the harsh insecticide plots. Aphid numbers increased more rapidly in the harsh insecticide plots that had been treated previously for bollworm control. The food spray and pymetrozine treatments reduced cotton aphids more effectively in the relay cropping system than in the isolated cotton system. Bollworms and cotton aphids did not reach pest status in 1997. The combination of a relay cropping system with a food spray did not enhance predator numbers and did not aid in retention of predators in cotton during August. Sucrose in the food spray attracted high numbers of bollworms in 1996.     

Use of predatory mirids for control of the tomato borer Tuta absoluta (Meyrick) in Sardinian greenhouse tomatoes

The introduction of Tuta absoluta in Sardinia (Italy) has caused an important increase in the number of insecticide treatments applied for pest management on greenhouse tomatoes, thus raising growers' demand for alternative control options. To evaluate the efficacy of releasing two specimens of Macrolophus pygmaeus or Nesidiocoris tenuis per m² for the control of tomato borer infestations, an investigation was conducted under field conditions between August 2010 and July 2011. The tests were carried out on 18 commercial greenhouse crops. Fifteen other greenhouses, where no biocontrol agents were released, were also surveyed as controls. The release of the mirid bugs resulted in poor population growth of predators, which reached a peak density of 1.79 individuals per plant. In approximately half of the cases, this was caused by the application of pesticides (usually abamectin and oxamyl) which are highly toxic to the predatory mirids. However, even in crops where only products regarded as harmless to beneficials were used (e.g. Bacillus thuringiensis‐based insecticides), both M. pygmaeus and N. tenuis failed to achieve the levels necessary for effective pest control. Presumably factors other than pesticide‐related mortality contributed significantly to delaying mirid population build‐up. Further studies are necessary to evaluate the feasibility of improving the efficacy of releases of the predatory mirids by the implementation of measures that may contribute to enhancing the establishment of these beneficials on tomato crops.     

Toxicity of spiromesifen to the developmental stages of Bemisia tabaci biotype B

BACKGROUND: Spiromesifen is a novel insecticidal/acaricidal compound derived from spirocyclic tetronic acids that acts effectively against whiteflies and mites via inhibition of acetyl‐CoA‐carboxylase, a lipid metabolism enzyme. The effects of spiromesifen on the developmental stages of the whitefly Bemisia tabaci (Gennadius) were studied under laboratory conditions to generate baseline action thresholds for field evaluations of the compound. RESULTS: Adult B. tabaci mortality rate after spiromesifen treatment (5 mg L^?1) was 40%. Treatment with 0.5 mg L^?1 reduced fecundity per female by more than 80%, and fertility was almost nil. LC₅₀ for eggs was 2.6 mg L^?1, and for first instar 0.5 mg L^?1. Scanning electron microscopy revealed that eggs laid by treated adult females had an abnormally perforated chorion, and females were unable to complete oviposition. Light and fluorescent microscopy showed significantly smaller eggs following treatment, and smaller, abnormally formed and improperly localized bacteriomes in eggs and nymphs. The number of ovarioles counted in females treated with 5 mg L^?1 was significantly reduced. Spiromesifen showed no cross‐resistance with other commonly used insecticides from different chemical groups, and resistance monitoring in Israel showed no development of field resistance to this insecticide after 1 year of use. CONCLUSION: The strong effect on juvenile stages of B. tabaci with a unique mode of action and the absence of cross‐resistance with major commonly used insecticides from different chemical groups suggest the use of spiromesifen in pest and resistance management programmes. Copyright © 2008 Society of Chemical Industry     

Inheritance of resistance to a new non‐steroidal ecdysone agonist,fufenozide, in the diamondback moth,Plutella xylostella (Lepidoptera: Plutellidae)

BACKGROUND: The diamondback moth (DBM), Plutella xylostella (L.), is a cosmopolitan pest of cruciferous crops. Fufenozide, a novel non‐steroidal ecdysone agonist, exhibits good efficacy and plays an increasingly important role in the control of Lepidopterous pests in China. A laboratory strain of DBM was selected for resistance to fufenozide, and the genetic basis of resistance was studied. RESULTS: The resistant strain, selected under laboratory conditions, exhibited a higher level of resistance to fufenozide (302.8‐fold based on LC₅₀s) than the laboratory susceptible strain. Mortality data from the testing of F₁ progeny of reciprocal crosses of resistant and susceptible DBM indicated that resistance was autosomal and incompletely recessive with a degree of dominance of ?0.664. Chi‐square analysis from responses of a backcross of crossed F₁ progeny and the resistant strain and F₂ progeny were highly significant, suggesting that the resistance was probably controlled by more than one gene. The estimated realised heritability (h²) of fufenozide resistance was 0.08, indicating that diamondback moth may have a lower chance of developing resistance to fufenozide than other kinds of insecticide. CONCLUSION: The resistance of DBM to fufenozide might be autosomal and incompletely recessive, and the resistance is probably controlled by more than one gene. These results provide the basic information for pest management programmes. Copyright © 2009 Society of Chemical Industry     

转cry1Ab基因抗虫籼稻对非靶标害虫白背飞虱发育与繁殖的影响

为了比较2个转cry1Ab基因抗虫籼稻品系B1和B6对其非靶标害虫白背飞虱敏感性与其非转基因亲本对照嘉早935的差异，采用历期测定和产卵行为电子记录等方法分别测定了白背飞虱于B1和B6及嘉早935上的发育历期、产卵行为及繁殖力。结果表明，该飞虱以B1和B6为食时，其雌雄若虫总发育历期均显著长于对照，其中在B1上各延长了1．3和1．5天，B6延长了2．0和1．4天。产卵行为的电子记录结果表明，该飞虱在B1和B6上的产卵频次、一次产卵时间及总产卵时间与对照相比均无显著差异。在寄主植株可选择时，该飞虱有偏爱于B1上产卵，其上的产卵痕数、卵块数和总产卵量明显多于对照；而不嗜好于B6上产卵，其上的卵块及其卵粒数、总产卵量明显少于对照。然而，在寄主植株不可选择时，则未观察到这种差异。就卵孵化率而言，不论在寄主可选择还是不可选择时，与对照相比B1和B6对其均无显著的不利影响。     

条沙叶蝉生物学与生态学研究

作者依据成虫产卵、若虫存活与发育等指标测定了条沙叶蝉对19种供试禾本科作物及杂草的寄主适应性,明确寄主植物14种,食料植物4种,非寄主食料植物1种。同时发现,不同小麦品种对条沙叶蝉存在不同程度抗虫性。通过室内试验和田间调查,明确条沙叶蝉各虫态生活习性及在关中年生活史和发生特点,在关中,条沙叶蝉1年发生4代,以卵越冬,全年各世代主要在杂草地完成周年发育循环,麦田发生条沙叶蝉主要是在小麦秋苗期。在20、25、30、35℃4种恒温与狗尾草、小麦、玉米3种食料条件下初步明确温度、食料对条沙叶蝉若虫发育、存活与成虫寿命及产卵的影响。     

Toxicity of selected insecticides to the two-spot ladybird <Emphasis Type="Italic">Adalia bipunctata</Emphasis>

The toxicity of pirimicarb, imidacloprid, dimethoate, lambda-cyhalothrin, flonicamid and spinosad to the two-spot ladybird, Adalia bipunctata, was evaluated in a laboratory study. Susceptibility of fourth instars and female adults was assessed by measuring toxicity via residual contact and ingestion through feeding on contaminated green peach aphids (Myzus persicae). Flonicamid and spinosad had no lethal effects on larvae and female adults. Pirimicarb was harmless to the predator by ingestion exposure but showed some residual toxicity at high concentrations to both larval and adult stages. Imidacloprid was highly toxic to the larval stage by residual and ingestion exposure but caused very low adult mortality when ingested through contaminated prey. Dimethoate and lambda-cyhalothrin were highly toxic to both the larval and adult stages of the ladybird. Our findings indicate that pest management programs in agricultural crops using dimethoate, lambda-cyhalothrin and, to a lesser degree, imidacloprid, are detrimental to A. bipunctata, whereas pirimicarb, flonicamid and spinosad are more compatible with the use of this predator.     

蠋蝽猎物—黏虫的室内种群复壮

猎物的质量直接决定了天敌的质量和饲养规模。蠋蝽是一种重要的捕食性天敌,其若虫和成虫对鳞翅目害虫幼虫均有较强的捕食能力。目前蠋蝽主要依靠黏虫来饲养。但在长期室内饲养过程中黏虫种群出现衰退现象,进而制约了蠋蝽规模化繁育。本文旨在研究黏虫种群复壮措施,为蠋蝽的规模化繁育提供技术支撑。为此,采用回接自然寄主和室内与室外种群杂交的方式评价了黏虫的种群复壮效果。结果表明,回接自然寄主玉米叶后黏虫的幼虫发育历期(18.03 d)较人工饲料饲养组(21.26 d)显著缩短,蛹重(369.00 mg)和成虫产卵量(770.88粒/雌)显著高于人工饲料饲养组(323.56 mg, 532.73粒/雌),但二者的蛹历期和成虫寿命无显著差异。杂交试验结果表明,4种交配方式产生的F₁代产卵前期、雌雄成虫寿命及其子代幼虫和蛹的发育历期无显著差异,但产卵期、产卵量及蛹重存在差异。其中以田间雌性×田间雄性(YF×YM)组合的产卵期最长(8.07 d)和产卵量最高(938.77粒/雌),而以田间雌性×室内雄性(YF×EM)组合的蛹最重(354.59 mg)。这些结果显示,通过回接自然寄主和室内与室...     

Response of a red clone of Myzus persicae (Hemiptera: Aphididae) to sublethal concentrations of imidacloprid in the laboratory and greenhouse

BACKGROUND: Pest resurgence following a pesticide application may occur owing to a stimulatory (hormetic) response to sublethal insecticide concentrations. The objective of the present study was to examine the potential for a greenhouse‐derived red clone of Myzus persicae to exhibit resurgence owing to a hormetic response following a systemic imidacloprid treatment in a bell pepper greenhouse. RESULTS: No differences in mortality and fecundity were observed among apterous adults exposed to sublethal imidacloprid concentrations on excised pepper leaves fed aqueous solutions of imidacloprid. Survival of first‐generation progeny was negatively affected by imidacloprid exposure, yet surviving progeny exhibited no differences in development rates or fecundity from progeny of adults unexposed to imidacloprid. Aphid mortality declined most rapidly in clip cages on pepper leaves at the top of the pepper canopy as compared with leaves present at the middle or bottom of the pepper canopy. CONCLUSION: Imidacloprid decays rapidly in mature pepper plants, resulting in sublethal concentrations in the upper canopy in as little as 4 weeks. Sublethal insecticide concentrations have been implicated in the resurgence of pest populations; however, exposure to sublethal doses of imidacloprid are unlikely to result in pesticide‐induced resurgence of the M. persicae aphid clone examined in this study. Copyright © 2011 Society of Chemical Industry     

Laboratory evaluation of a botanical natural product (<Emphasis Type="Italic">AkseBio2</Emphasis>) against the pear psylla<Emphasis Type="Italic">Cacopsylla pyri</Emphasis>

A botanical natural product,AkseBio2, was evaluated under laboratory conditions for its oviposition deterrent, ovicidal and larvicidal (nymphicidal) effects against the pear psyllaCacopsylla pyri (L.) (Hemiptera: Psyllidae). The product exhibited a strong oviposition deterrent effect for winterform and summerform females and caused a reduction in the total number of eggs laid in both choice and no-choice assays. Significant mortalities in freshly laid eggs (0–48 h) and various nymphal stages of the pest were recorded in toxicity assays. At a concentration of 0.1% (formulation), the highest biological activity of the product was recorded against the young (1st and 2nd) nymphal stages (up to 87.4% mortality) in comparison with the other biological stages of the pest. It was less active against the older (3rd-5th) nymphs, causing 62.1% mortality at the same concentration. In assays with non-target organisms, a significant negative effect was not observed. There were no significant changes on treated plants up to 7 days after treatment in any trial, nor was there any phytotoxicity on plant tissue as a result ofAkseBio2 treatments. The results suggest that the product can be used in psylla control instead of synthetic insecticides and may serve as an integrated pest management (IPM) component in pear orchards. http://www.phytoparasitica.org posting July 14, 2004.