Efficacy of the pear ester as a monitoring tool for codling moth Cydia pomonella (Lepidoptera: Tortricidae) in New Zealand apple orchards

BACKGROUND: The behavioural response of both sexes of codling moth, Cydia pomonella to the pear-derived kairomone (ethyl (2E,4Z)-2,4-decadienoate), codling moth sex pheromone (E,E-8,10-dodecadien-1-ol), and sex pheromone combined with the pear derived kairomone loaded into red rubber septum were investigated in trapping experiments in New Zealand apple orchards. A range of 0.01-10.0 mg of pheromone loading in rubber septum dispensers was tested and the highest catch of males was in traps baited with 1.0 mg. No dose response in trap catch of males was seen in traps baited with different amounts of pear-derived kairomone (0.01-10.0 mg). RESULTS: The number of females caught was significantly affected by the amount of pear derived kairomone used to bait traps, with the highest catch obtained at 10 mg loading. The attractiveness of sex pheromone was not enhanced by the addition of the kairomone either when used in the same bait or in a separate bait. The mean number of males captured in traps was reduced by 44% when the pheromone and kairomone were combined at ratio of 1:1 (0.1 mg pheromone: 0.1 mg kairomone) in separate sources. CONCLUSION: Kairomone baited traps showed some potential for monitoring the flight activity of female C. pomonella in apple orchards in two locations (Canterbury and Hawke's Bay). However, the number of male moths caught was low as compared to the number of male moths caught in pheromone-baited traps, and therefore the sex pheromone should continue to be used for monitoring male activity.     

Toxicity of azinphos-methyl to various development stages of the codling moth Cydia pomonella (Lepidoptera: Tortricidae)

The response to azinphos-methyl of different life-stages of the codling moth Cydia pomonella (L.) was studied. A similarity in response to azinphos-methyl (LC(50), LC(90)) was observed in neonate larvae obtained from the first and second generations of field populations. Mortality rates for neonate larvae of a field population cross-bred with a laboratory colony were lower (by a factor of 1.2-2.2) in comparison with field neonate larvae. The mortality rate of larvae from a laboratory colony exposed to artificial diet containing azinphos-methyl gradually decreased at older instars. The mortality rates of fifth-instar larvae were remarkably low when exposed to artificial diet mixed with azinphos-methyl or when topically treated with the insecticide. One- to three-day-old females were more sensitive than males of the same age, whereas the opposite was observed in 14-to 17-day-old adults. Mortality rates of 14- to 17-day-old adults were higher than those under 10 days old. No significant difference in sensitivity to the organophosphorus compound was noticed between the sexes of 7- to 10-day-old adults. Neonate larvae of the codling moth can serve as a target life-stage for various groups of pesticides, and the importance of using such a stage as a standardized methodology for monitoring resistance in the codling moth is discussed.     

Reduced egg viability in codling moth Cydia pomonella (L.) (Lepidoptera: Tortricidae) following adult exposure to novaluron

BACKGROUND: The codling moth, Cydia pomonella (L.), is one of the principal pests of pome fruits in the world. The effects of novaluron, a benzoylurea chitin synthesis inhibitor insecticide registered for use on apples in the USA, on fecundity and egg viability in codling moth were studied under laboratory conditions. Three different exposure methods were investigated: ingestion, contact and topical spray. Additionally, the duration of novaluron sublethal effects was measured subsequent to the three modes of exposure. RESULTS: The fecundity of codling moth adults was not significantly affected by novaluron with any of the exposure methods. However, novaluron did cause significant reductions in the proportion of egg hatch with all three exposure methods. The duration of sublethal effects was 9 days or more for all modes of exposure, but with the topical spray these effects began to diminish after 6 days. CONCLUSION: Novaluron does not affect fecundity in codling moth, but has significant sublethal activity by reducing egg viability subsequent to adult exposure. The topical, contact and ingestion exposures all induce sublethal effects after exposure, and these persist to various degrees throughout codling moth oviposition. A more complete understanding of novaluron's lethal and sublethal activities will help IPM practitioners optimize its use for management of the codling moth. Copyright © 2008 Society of Chemical Industry     

Diurnal variation of walnut tree volatiles and electrophysiological responses in Cydia pomonella (Lepidoptera: Tortricidae)

BACKGROUND: In recent years, many studies have been carried out on the behavioural and electrophysiological responses of Cydia pomonella (L.) to host volatile emissions, to find alternative attractants to the sex pheromone for pest monitoring. These studies have focused on apple and pear, and very little has been done on walnut. In the present work, the diurnal and seasonal variation in walnut volatile emissions and the electrophysiological response of C. pomonella have been studied. RESULTS: Ninety compounds were detected in walnut emissions, mainly monoterpenes and sesquiterpenes. The most abundant compound was β‐pinene, which, together with (Z)‐3‐hexenyl acetate, (E)‐β‐ocimene, limonene, germacrene D, 1,8‐cineole, sabinene, (E)‐β‐farnesene, (E)‐β‐caryophyllene, β‐myrcene and β‐phellandrene, constituted between 81.9 and 90.5% of the total chromatographic area. Differences between seasonal periods were significant for 39 compounds, and between daytimes for 14 compounds. Discernible and consistent EAD responses were detected to 11 walnut‐origin compounds, and confirmed with synthetics to seven of them. Except for alloocimene, pinocarvone and caryophyllene oxide, all these compounds are also emitted by apple. CONCLUSION: Walnut volatile emissions differ widely from apple ones, but both share many compounds that are EAD‐active in C. pomonella. However, among EAD‐active compounds there are three walnut‐specific ones, which should be further tested in behavioural assays. Copyright © 2008 Society of Chemical Industry     

Adding microencapsulated pear ester to insecticides for control of Cydia pomonella (Lepidoptera: Tortricidae) in apple

BACKGROUND: The possibility of improving the efficacy of various insecticides for codling moth, Cydia pomonella (L.), by the addition of a microencapsulated formulation of pear ester, ethyl (2E, 4Z)‐2,4‐decadienoate (PE‐MEC, 5% AI), was evaluated in field trials in apple from 2005 to 2009. RESULTS: The addition of PE‐MEC (<3.0 g AI ha^?1) significantly lowered fruit injury with low rates of organophosphate and neonicotinoid insecticides. The addition of PE‐MEC (1.48 g AI ha^?1) to maximum label rates of insecticides with moderate activity for codling moth, such as ebamectin benzoate, spinosad and methoxyfenozide, significantly improved their effectiveness. However, PE‐MEC did not consistently improve the activity of maximum label rates of either rynaxypyr or spinetoram. The addition of PE‐MEC with seasonal spray programs of acetamiprid and azinphos‐methyl in combination with the use of sex pheromones for mating disruption provided the most effective control. CONCLUSION: The addition of PE‐MEC can improve the effectiveness of some insecticides for codling moth in apple. Insecticides active via dermal toxicity are more strongly improved by the addition of PE‐MEC. Season‐long use of PE‐MEC can also augment the effectiveness of mating disruption. Adding PE‐MEC to variable integrated management programs for C. pomonella should be further investigated. Published 2012 by John Wiley & Sons, Ltd.     

Control of the codling moth (cydia pomonella) in apple and pear orchards in Israel by mating disruption

Control of the codling moth,Cydia pomonella (L.) (Lepidoptera: Tortricidae), by pheromone-mediated mating disruption, was studied in Israel using two types of dispensers: Shin-Etsu twist-tie (normal and long-life) and TNO matrix formulation (square wafers). Factors affecting mating disruption: initial pest population density, timing of the pheromone application, early season insecticide treatments and monitoring of the pest, were evaluated. Efficacy of mating disruption was assessed by comparing catch of males in pheromone traps located in pheromone-treated and chemically sprayed control plots. Fruit infestation during the season and at picking time was the major criterion to assess mating disruption. The preferred time for pheromone application was before the first flight of the moth. When pheromones were applied at a later stage, one or two early insecticide sprays had to be used to reduce the initial level of the codling moth population. In all tests, trap catch in pheromone-treated plots was drastically reduced as compared with respective control plots. In pheromone-treated plots where total seasonal trap catch (after pheromone application) was less than 12 males/trap, fruit infestation was less than 1.5%; zero trap catch resulted in 0.1-0.3% infestation. At high population levels, mating disruption was ineffective, with the rate of infestation at picking-time being similar in pheromone-treated and control plots. All the field tests indicated that mating disruption with either Shin-Etsu ropes or TNO squares can control codling moth infestations in apple and pear orchards, at relatively low densities of the pest, as efficiently as commercial insecticide sprays.     

Potential of Heterorhabditis zealandica (Rhabditida: Heterorhabditidae) for the control of codling moth,Cydia pomonella (Lepidoptera: Tortricidae) in semi-field trials under South African conditions

Infection of codling moth, Cydia pomonella (L.), larvae by the entomopathogenic nematode, Heterorhabditis zealandica, was studied under semi-field conditions. Late-instar diapausing codling moth larvae, coccooned in perforated cardboard strips, were used in all trials to evaluate the nematode treatments involved. A morning application of 0.5, 1.0 and 1.5 MM infective juveniles (IJs) per tree resulted in 85%, 95% and 100% codling moth larval infection, respectively. Contrasting results were obtained for an evening application, with low levels of codling moth infection (<50%). Nematode treatment strips placed in direct sunlight resulted in almost no infection (<10%), opposed to strips attaining 67% infection placed in the shade.     

Diflubenzuron and oogenesis in the codling moth,Cydia pomonella (L.)

Diflubenzuron, topically applied (0·5 μg insect^?-1) to Cydia pomonella (L.) at pupal ecdysis disturbed growth and development of oocytes. It delayed the adult ecdysis and caused a decrease in both thickness of the follicular epithelium and the size of the basal oocyte during the pupal development. On the other hand, the size of basal oocytes, the protein content per ovary and the number of oocytes per ovary recorded in newly emerged adults were significantly reduced after diflubenzuron treatment. These results, together with observations in several other species, indicate that the reduction in fecundity and egg viability is probably due to interference of diflubenzuron with the vitellogenesis process.     

Toxicological and biochemical response to azinphos-methyl in Cydia pomonella L. (Lepidoptera: Tortricidae) among orchards from the Argentinian Patagonia

BACKGROUND: Azinphos‐methyl is the main insecticide used to control codling moth on apple and pears in Northern Patagonia. The aim of this study was to evaluate the toxicological and biochemical response of diapausing larvae of codling moth in orchards subjected to different insecticide selection pressure. RESULTS: Dose–mortality assays with azinphos‐methyl in diapausing larvae of Cydia pomonella L. showed significant differences between the LD₉₅ from a population collected in one untreated orchard (2.52 µg moth^?1) compared with that in a laboratory‐susceptible population (0.33 µg moth^?1). Toxicity to azinphos‐methyl in field populations of diapausing larvae collected during 2003–2005 was evaluated by topical application of a discriminating dose (2.5 µg moth^?1) that was obtained from larvae collected in the untreated orchard (field reference strain). Significantly lower mortality (37.71–84.21%) was observed in three out of eight field populations compared with that in the field reference strain. Most of the field populations showed higher esterase activity than that determined in both the laboratory susceptible and the field reference strains. Moreover, there was a high association between esterase activity and mortality (R² = 0.64) among the field populations. On the other hand, a poor correlation was observed between glutathione S‐transferase activity and mortality (R² = 0.33) among larvae collected from different orchards. CONCLUSIONS: All the field populations evaluated exhibited some degree of azinphos‐methyl tolerance in relation to the laboratory susceptible strain. Biochemical results demonstrated that esterases are at least one of the principal mechanisms involved in tolerance to this insecticide. Copyright © 2008 Society of Chemical Industry     

Effects of reservoir dispenser height on efficacy of mating disruption of codling moth (Lepidoptera: Tortricidae) in apple

BACKGROUND: The effect of varying the height of reservoir dispensers for mating disruption of codling moth, Cydia pomonella (L.), was investigated. The goal was to improve the effectiveness of C. pomonella mating disruption through improved understanding of adult distribution within the tree canopy and the impact of pheromone dispenser placement on disruption. Two dispensers per tree were placed at 2 m and 4 m and/or one dispenser at each height on the tree at a label rate of 1000 units ha^?1. Monitoring traps and tethered female moths were deployed in plots at 2 and 4 m heights to assess treatment effects by catches or matings respectively. RESULTS: Fewest male moths were captured with all dispensers placed at 4 m. Female mating was lowest, and with least variation between females tethered at 2 and 4 m, when dispensers were placed simultaneously at 2 and 4 m (28% mated). Mating was 32% with both dispensers at 4 m, 38% with both dispensers at 2 m and 46% in the no disruption control. Mating was highest across treatments when females were tethered at 2 m and dispensers placed at 4 m (40%), and when females were tethered at 4 m with dispensers placed at 2 m (46%). CONCLUSION: Traps at 4 m in trees captured more male moths than traps at 2 m, regardless of disruption dispenser positioning. Female mating was lowest when dispensers were placed simultaneously at 2 and 4 m, suggesting that current recommendations for placement of reservoir dispensers in tree crowns may be suboptimal. Copyright © 2011 Society of Chemical Industry     

Monitoring resistance to diflubenzuron and deltamethrin in French codling moth populations (Cydia pomonella)

French populations of codling moth have developed resistance to several insecticide classes. The susceptibility of susceptible and resistant laboratory strains to diflubenzuron and deltamethrin was evaluated using different exposure methods against various life stages. The tarsal contact method for adults was found to be an appropriate method for testing neurotoxic compounds such as deltamethrin. Insect growth inhibitors, like diflubenzuron, need to be analysed on juvenile instars. Monitoring methodologies were developed and evaluated (a) on neonates obtained by crossing field‐collected males with virgin females from the susceptible laboratory strain so as to overcome the problem of reduced fertility of wild females and (b) on diapausing larvae. All 36 populations analysed exhibited significant levels of resistance to both diflubenzuron and deltamethrin. Resistance to the two compounds was linked, regardless of the cultivation methods used in the monitored area. The monitoring methodologies will be implemented to evaluate the evolution of resistance according to the resistance management strategies that have been adopted. © 2000 Society of Chemical Industry     

Cross‐resistance between azinphos‐methyl and acetamiprid in populations of codling moth,Cydia pomonella (L.) (Lepidoptera: Tortricidae), from Washington State

BACKGROUND: Codling moth, Cydia pomonella (L.), has been intensely managed with the organophosphate insecticide azinphos‐methyl for 50 years, and populations have developed resistance. New management programs have been developed and implemented that rely more heavily on other classes of insecticides. A prerequisite for developing effective resistance management strategies for these compounds is to establish their current levels of effectiveness. Adult and neonate larval assays were conducted to assess the response of field‐collected codling moth populations from apple in Washington State. RESULTS: Male codling moth populations exhibited a range of responses to a discriminating concentration of azinphos‐methyl in a survey of 20 populations. Populations from certified organic orchards were more susceptible than those from conventional orchards. Mean fecundity was inversely related to azinphos‐methyl tolerance. Male responses to azinphos‐methyl and acetamiprid varied significantly among populations and were correlated. The residual effectiveness of field applications of both insecticides varied significantly against neonate larvae. Neonate bioassays with insecticide‐dipped fruit found significant differences among populations with azinphos‐methyl, acetamiprid, methoxyfenozide and spinosad, but not with esfenvalerate. CONCLUSION: These results support a concern that alternation of insecticides with different modes of action may not be a sufficient strategy to avoid the evolution of broad‐spectrum insecticide resistance by codling moth. Published 2010 by John Wiley & Sons, Ltd.     

苹果蠹蛾在中国的适生性分析

苹果蠹蛾是严重危害全球水果生产的一种重要害虫。本研究根据中国760个气象站点的气象数据和苹果蠹蛾生物学数据,综合运用CLMEX模型和ArcGIS分析相结合的方法,对苹果蠹蛾在中国的适生性进行分析。分析结果表明:苹果蠹蛾在我国的适生区域较为广泛。中高度适生区主要包括黑龙江、内蒙古、山西、宁夏、甘肃,吉林、北京、陕西、新疆、西藏的大部分地区,辽宁西部、河北西部和北部、青海北部、云南北部、四川西部、贵州西部及山东沿海地区。     

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     

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     

苹果蠹蛾的生物学特性及消长动态

苹果蠹蛾(Cydia pomonellaL.)在甘肃张掖地区1年发生2代和一个不完整的第3代,以老熟幼虫在粗皮裂缝、翘皮下、树洞中、主干分枝及主枝分叉处的缝隙中结茧越冬。4月上旬,越冬幼虫陆续开始化蛹,5月中旬为越冬代成虫羽化高峰期,5月中下旬1代幼虫蛀果为害,7月中下旬为1代成虫羽化高峰期,7月中下旬至8月上旬为2代幼虫为害高峰期,9月中下旬出现不完整第3代幼虫。在甘肃张掖地区,6月中旬至7月上旬越冬代成虫和第1代成虫之间有一段明显的间断期,说明第1代苹果蠹蛾发生的趋势相对较为独立,世代重叠现象发生不重。     

苹果蠹蛾的生物学特性及消长动态

苹果蠹蛾(Cydia pomonellaL.)在甘肃张掖地区1年发生2代和一个不完整的第3代,以老熟幼虫在粗皮裂缝、翘皮下、树洞中、主干分枝及主枝分叉处的缝隙中结茧越冬。4月上旬,越冬幼虫陆续开始化蛹,5月中旬为越冬代成虫羽化高峰期,5月中下旬1代幼虫蛀果为害,7月中下旬为1代成虫羽化高峰期,7月中下旬至8月上旬为2代幼虫为害高峰期,9月中下旬出现不完整第3代幼虫。在甘肃张掖地区,6月中旬至7月上旬越冬代成虫和第1代成虫之间有一段明显的间断期,说明第1代苹果蠹蛾发生的趋势相对较为独立,世代重叠现象发生不重。