Mating disruption of pea moth (Cydia nigricana) in organic peas (Pisum sativum)

We appraised mating disruption (MD) to control pea moth, Cydia nigricana (Fabricius) (Lepidoptera: Tortricidae), by assessing male attraction to monitor traps, larval pod infestation, and larval age structure in pheromone‐treated and untreated grain pea fields [Pisum sativum L. (Fabaceae)], over a 5‐year period. Cellulose pheromone dispensers were manually attached to the top shoots of pea plants and released 540 mg ha^?1 day^?1 synthetic pheromone E8,E10‐dodecadien‐1‐yl acetate in a first test series (2000–2001) and ca. 4 200 mg pheromone ha^?1 day^?1 in a second series (2004–2006). The dispensers had a half‐life of about 30 days. Although male attraction to pheromone monitoring traps was largely suppressed at the edges and within MD fields in both test series, MD treatments did not reduce pod infestation in the open field in 2000 and 2001. In the 2004–2006 series, larval damage reduction was achieved in the majority of the trials but overall MD efficacy in the open field was only 61% and not significant. In contrast, in field cages placed within the experimental sites and supplied with unmated pea moths, MD control was consistently high and significant. There were no obvious differences in the larval age distribution in all MD and control treatments, suggesting that infestations started and developed further similarly. As a univoltine species, C. nigricana larvae stay in the soil of pea fields for hibernation and pupate. The following year, emerging adults disperse and fly to the closest pea crop. Combined emergence site and pea crop treatments were conducted over 2 years to include this early migration phase of C. nigricana adults. However, the emergence site treatments did not enhance MD‐control efficacy. We conclude that mating activity was only prevented in cage tests, whereas substantial mating occurred during the transit phase outside the pheromone‐treated fields either within non‐crop vegetation and/or at the edges of pheromone‐treated pea fields orientated upwind. Thus, resulting gravid female entry can be regarded as the major constraint to reliable MD control.     

Pheromone pre-exposure and mating modulate codling moth (Lepidoptera: Tortricidae) response to host plant volatiles

Abstract 1 Two codling moth Cydia pomonella kairomonal attractants, ethyl (E,Z)‐2,4‐decadienoate (pear ester) and (E)‐β‐farnesene, were tested in an insecticide‐sprayed apple orchard and an orchard treated for mating disruption with synthetic pheromone (E,E)‐8,10‐dodecadienol (codlemone). Male captures with pear ester were higher in the pheromone‐treated than in the insecticide‐treated orchard, whereas captures with (E)‐β‐farnesene were not different. Subsequent wind tunnel experiments confirmed that pre‐exposure to sex pheromone codlemone increased the behavioural response of codling moth males to pear ester. This supports the idea that male attraction to the plant volatile pear ester and sex pheromone codlemone is mediated through the same sensory channels. 2 Pear ester is a bisexual codling moth attractant and even captures of female moths were significantly increased in the pheromone‐treated orchard. In the laboratory wind tunnel, pheromone pre‐exposure had no effect on female response to pear ester, but significantly more mated than unmated codling moth females flew upwind towards a pear ester source. Differences in mating status in insecticide‐treated vs. pheromone‐treated orchards may thus account for the differences in female trap captures with pear ester. 3 These findings are important with respect to monitoring of codling moth with pear ester in mating disruption orchards. They also emphasize the importance of host plant volatiles in pheromone‐mediated mating disruption, which has been neglected to date.     

Optimization of pheromone dosage for gypsy moth mating disruption

The effect of aerial applications of the pheromone disparlure at varying dosages on mating disruption in low‐density gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), populations was determined in field plots in Virginia, USA during 2000 and 2002. Six dosages [0.15, 0.75, 3, 15, 37.5, and 75 g active ingredient (AI)/ha] of disparlure were tested during the 2‐year study. A strongly positive dose–response relationship was observed between pheromone dosages and mating disruption, as measured by the reduction in male moth capture in pheromone‐baited traps and mating successes of females. Dosages of pheromone 15 g AI/ha (15, 37.5, and 75 g AI/ha) reduced the mating success of females by >99% and significantly reduced male moth catches in pheromone‐baited traps compared to untreated plots. Pheromone dosages <15 g AI/ha also reduced trap catch, but to a lesser extent than dosages 15 g AI/ha. Furthermore, the effectiveness of the lower dosage treatments (0.15, 0.75, and 3 g AI/ha) declined over time, so that by the end of the study, male moth catches in traps were significantly lower in plots treated with pheromone dosages 15 g AI/ha. The dosage of 75 g AI/ha was initially replaced by a dosage of 37.5 g AI/ha in the USDA Forest Service Slow‐the‐Spread (STS) of the Gypsy Moth management program, but the program is currently making the transition to a dosage of 15 g AI/ha. These changes in applied dosages have resulted in a reduction in the cost of gypsy moth mating disruption treatments.     

Development of 2‐phenylethanol plus acetic acid lures to monitor obliquebanded leafroller (Lepidoptera: Tortricidae) under mating disruption

We evaluated the effectiveness of 2‐phenylethanol (PET) in combination with acetic acid (AA) as a binary lure for monitoring male and female obliquebanded leafroller, Choristoneura rosaceana (Harris). Studies were conducted in apple, Malus domestica Borkhausen, orchards treated with or without sex pheromone dispensers for mating disruption (MD). Open polypropylene vials, closed membrane cups, and rubber septa loaded with AA and/or PET in varying amounts were first evaluated in a series of trapping experiments. Membrane cups loaded with 800 mg of PET were as effective as 10‐mg septa, but longer lasting, and were comparable to the open vials. A membrane cup AA lure was effective in tests, but further work is needed to increase its release rate and extend its activity. Catches of codling moth, Cydia pomonella (L.), and C. rosaceana were unaffected by combining PET with (E,E)‐8,10‐dodecadien‐1‐ol, the sex pheromone of codling moth, pear ester, (E,Z)‐2,4‐ethyl‐decadienoate and AA lures. Adding (E)‐4,8‐dimethyl‐1,3,7‐nonatriene to this blend to enhance codling moth catch significantly reduced catches of C. rosaceana. PET + AA was a more attractive binary lure than AA plus phenylacetonitrile (PAN) for C. rosaceana. The addition of PET or PAN to traps already baited with the sex pheromone of C. rosaceana significantly reduced male catches. Traps baited with PET + AA placed in blocks not treated with MD caught significantly fewer C. rosaceana than traps baited with sex pheromone. In comparison, sex pheromone‐baited traps in MD blocks caught ≤1 male moth per season which was significantly lower than total moth (>10) or female moth (≥3) catch in these blocks with PET + AA. A high proportion (>70%) of trapped females were mated in both untreated and MD‐treated orchards. Further refinement of this binary, bisexual lure using membrane cup technology may allow the establishment of action thresholds and improve management timings for C. rosaceana.     

Pheromone release rate determines whether sexual communication of Oriental fruit moth is disrupted competitively vs. non‐competitively

Communicational disruption mechanisms for Oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), were determined using a suite of mathematical tools and graphical operations that enable differentiation between competitive attraction and non‐competitive mechanisms of disruption. Research was conducted in 20 field cages, each covering 12 mature apple trees. Commercial monitoring lures releasing Oriental fruit moth pheromone at a rate of 0.04 μg h^?1 and distributed at densities of 0, 1, 2, 4, 8, and 17 per cage were used to evaluate the effect of low‐releasing dispensers on the disruption of sexual communication. Graphical analyses revealed that near‐female‐equivalent pheromone dispensers disrupted Oriental fruit moth competitively. Commercial mating disruption dispensers releasing Oriental fruit moth pheromone at 60 μg h^?1 and deployed at 0, 4, 6, 10, 15, 20, and 30 per cage were used to evaluate the effect of high‐releasing dispensers on the disruption of sexual communication. Oriental fruit moth disruption shifted to a non‐competitive mechanism for high‐releasing dispensers. This is the first time such a shift in disruption mechanism has been demonstrated against a background of otherwise identical experimental conditions. Near‐female‐equivalent pheromone dispensers were also used to quantify the additive effect of an attract‐and‐remove control strategy compared with competitive mating disruption. We report a five‐fold reduction in Oriental fruit moth captures under attract‐and‐remove compared to mating disruption using near‐female‐equivalent dispensers. Surprisingly, release of female Oriental fruit moths into these large‐cage disruption studies had no measurable impact on male trapping.     

A comparison of various mating disruption technologies for control of two internally feeding Lepidoptera in apples

Sex pheromone mating disruption (MD) is an approach used to control several moth pest species of pome fruit by disrupting the ability of the males to find females and consequently prevent mating. The following experiments were performed to determine the effectiveness of several new and experimental sex pheromone MD technologies, and dispenser densities for simultaneous control of the codling moth (CM), Cydia pomonella (L.), and the oriental fruit moth (OFM), Grapholita molesta (Busck) (both Lepidoptera: Tortricidae), in Pennsylvania apple orchards. In one study, three MD approaches to control CM and oriental fruit moth – CM and OFM Disrupt Micro‐Flakes, Isomate CM/OFM TT, and both a CideTrak OFM and a CideTrak CM dispenser containing both codlemone and pear ester – and an insecticides‐only treatment were compared over the course of 2 years. In the other studies, the efficacy of several CheckMate Duel dispenser densities (i.e., 250, 375, 425, and 500 dispensers ha^?1) were compared against Isomate CM/OFM TT, and an insecticides‐only treatment. The CideTrak CM/pear ester combination and Isomate CM/OFM TT treatments both substantially reduced CM captures in traps in 2007 and 2008. Meanwhile, OFM trap shutdown was highest in the CheckMate Duel densities of 375 (99.9 ± 0.08%) and 500 dispensers ha^?1 (98.9 ± 0.07%) and the Isomate CM/OFM TT treatment (98.0 ± 1.13%), and lowest in the 250 dispensers ha^?1 density treatment (94.3 ± 3.23%). In orchards where OFM is the dominant pest species, a CheckMate Duel dispenser density of 375 ha^?1 is necessary for effective control, whereas higher densities are needed to control CM.     

Large‐scale mating disruption of Ephestia spp. and Plodia interpunctella in Czech Republic,Greece and Italy

Field trials were carried out to evaluate the use of the pheromone (9Z,12E)‐tetradecadienyl acetate (TDA/ZETA) for mating disruption (MD) of Pyralidae moths associated with stored products, in most cases the Raisin moth, Ephestia cautella (Walker), Mediterranean flour moth, Ephestia kuehniella Zeller and Indianmeal moth, Plodia interpunctella (Hübner). The experiments were conducted in the Czech Republic, Greece and Italy during 2007 and 2008 in storage facilities that varied in their size and type, and included flour mills, retail stores, storage rooms with currants and raw grain stores. After a summer pre‐treatment monitoring period to assess moth population in, dispensers containing TDA were placed in the fall. Adjacent facilities without dispensers were used as control units. Pheromone‐baited traps were used to monitor the population fluctuation of the pyralid moths during the entire experimental periods. The presence of MD dispensers notably reduced the number of adults found in the traps in comparison with control rooms. Monitoring of female oviposition, measured as number of hatched larvae in cups containing food, indicated that there was a reduction in the number of larvae in the areas with MD dispensers. The results of the present work indicate that the use of mating disruption is feasible against pyralid moths in storage facilities, and should be further evaluated as a component of an integrated pest management based control strategy.     

Persistent effects of aerial applications of disparlure on gypsy moth: trap catch and mating success

In forest plots treated aerially with a plastic laminated flake formulation (Disrupt^® II) of the gypsy moth sex pheromone disparlure to disrupt gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), mating was monitored the year of treatment and 1–2 years after treatment to determine the effects of the treatment on suppression of trap catch and mating success. In the year of treatment, there was a greater than 95% reduction in trap catch and a greater than 98% reduction in mating success compared to controls. One year after treatment at a dosage of 37.5 g active ingredient (a.i.) ha^?1, trap catch was reduced by 46–56% and mating success was reduced by 60–79%. Both trap catch and mating success were significantly reduced compared to controls in plots treated 1 year previously at 15 g a.i. ha^?1. Trap catch, but not mating success, was significantly reduced 2 years after treatment at 37.5 g a.i. ha^?1. The efficacy of mating disruption (MD) treatments in the Slow‐the‐Spread of the Gypsy Moth program was significantly reduced 2 years compared to 1 year after treatment. No such reduction was observed in plots treated with aerial applications of Bacillus thuringiensis kurstaki. The higher apparent efficacy of MD treatments 1 year after application may result to some extent from the suppression of moth capture in pheromone traps from the persistent effects of the previous year's treatment.     

Potential of high‐density pheromone‐releasing microtraps for control of codling moth Cydia pomonella and obliquebanded leafroller Choristoneura rosaceana

Recent large‐cage studies with codling moth Cydia pomonella (L.) reveal that the removal of moths from an apple orchard using pheromone‐releasing traps is more effective at reducing capture in a central monitoring trap than is a mating disruption protocol without kill/capture. The present study uses open orchard 0.2‐ha plots comparing a high‐density trapping scenario with mating disruption to confirm those results. Two tortricid moth pests of tree fruit are studied: codling moth and obliquebanded leafroller Choristoneura rosaceana (Harris). Codling moth treatments include Isomate CM FLEX (ShinEtsu Ltd, Japan), nonsticky traps baited with Trécé CM lures (Trécé, Inc., Adair, Oklahoma), and sticky traps baited with Trécé CM lures, all at equal application rates of 500 dispensers ha^?1, as well as a no pheromone control. These microtraps are of a novel design, small and easy to apply, and potentially inexpensive to produce. Mating disruption using Isomate CM FLEX and nonsticky traps reduces codling moth capture in standard monitoring traps by 58% and 71%, respectively. The attract‐and‐remove treatment with sticky traps reduces capture by 92%. Obliquebanded leafroller treatments include Isomate OBLR/PLR Plus and Pherocon IIB microtraps baited with Trécé OBLR lures, both applied at 500 dispensers ha^?1, as well as a no pheromone control. Mating disruption reduces capture in monitoring traps by 69%. The attract‐and‐remove treatment reduces capture by 85%. Both studies suggest that an attract‐and‐remove approach has the potential to provide superior control of moth populations compared with that achieved by mating disruption operating by competitive attraction.     

Long‐term evaluation of field‐wide oriental beetle (Col., Scarabaeidae) mating disruption in blueberries using female‐mimic pheromone lures

The oriental beetle, Anomala orientalis (Waterhouse) (Col., Scarabaeidae), is the most important root‐feeding pest of blueberries and turfgrass in New Jersey, USA. Previous studies showed that mating disruption is a feasible option for oriental beetle management; however, assessing its efficiency can be challenging, and little is known on its long‐term effects. Accordingly, we conducted studies to investigate low‐dose pheromone lures equivalent to oriental beetle females (i.e. female mimics) as easy‐to‐use indicators of mating disruption success, determine the distance at which oriental beetle males respond to female‐mimic lures and assess the long‐term (3‐year) effects of mating disruption on oriental beetle populations in entire blueberry fields. Our studies showed that rubber septa baited with 0.3 μg of the oriental beetle sex pheromone (Z)‐7‐tetradecen‐2‐one attract similar numbers of males as compared with virgin females and can thus be used as a female mimic. The range of attraction of this lure was found to be also similar to virgin females and <30 m. In blueberries, mating disruption provided 87% inhibition of oriental beetle populations (trap shutdown) over a 3‐year period. Oriental beetle male captures in disrupted fields were threefold higher along the field edges than in the field interiors, indicating movement of males from nearby areas into the pheromone‐treated fields. In addition, mating disruption reduced male attraction to female‐mimic lures by 93% in all 3 years and reduced the number of larvae in sentinel potted plants in 1 of 2 years. These results show for the first time that mating disruption provides consistent long‐term field‐wide control of oriental beetle populations and that female‐mimic pheromone lures can be used as a new tool to assess oriental beetle mating disruption success.     

Attractiveness of year-old polyethylene Isonet sex pheromone dispensers for Lobesia botrana

In this study, we have compared the release of sex pheromone from mating disruption dispensers exposed in the field for 12 months and from calling females. The main pheromone component of the grapevine moth, Lobesia botrana (D. and S.) (Lepidoptera: Tortricidae), is (E)‐7,(Z)‐9‐dodecadienyl acetate, and a minor component is (Z)‐9‐dodecenyl acetate. Aged dispensers from two different years emitted a much higher amount of both pheromone components than calling females. However, the summer temperature during field exposure influenced the release from mating disruption dispensers the following year. In the wind tunnel, male L. botrana were equally attracted to 12‐month, field‐exposed dispensers, a standard monitoring pheromone lure, and to synthetic (E)‐7,(Z)‐9‐dodecadienyl acetate sprayed at the rate of 0.6–60 ng h^?1. Field trapping tests confirmed that aged dispensers from both years were at least as attractive to L. botrana males as a standard monitoring pheromone lure. The possible contribution of previously applied dispensers to the mating disruption efficacy during following applications is discussed.     

Calibration of an EAG system to measure airborne concentration of pheromone formulated for mating disruption of the pink bollworm moth, Pectinophora gossypiella (Saunders) (Lep., Gelechiidae)

Abstract: Electroantennogram (EAG) devices, used to measure airborne pheromone density in mating disruption experiments, so far have provided only ‘relative units’ of concentration rather than absolute concentration values. This paper describes a technique to measure the amount of pheromone delivered by calibration syringes into the Kaiserslautern EAG pheromone measurement device, thereby allowing such relative units of concentration to be converted into absolute concentrations. The synthetic pheromone used in these calibrations is of Pectinophora gossypiella (Saunders), the pink bollworm moth, and consists of a 1 : 1 mix of (Z,Z)‐ and (Z,E)‐7,11‐hexadecadienyl acetates. The syringe, driven as in field use, delivers its pheromone–air mixture into a glass capillary where it is adsorbed. The amount of pheromone trapped is measured by gas chromatography. The results show a linear relationship between the ratio of pheromone : silicone oil in a syringe and the pheromone concentration in the air puffs it generates. Efficacious mating disruption of P. gossypiella in cotton occurs with 10^?6 relative EAG units, which corresponds to an aerial pheromone density of 1.7 ± 0.15 ng/m³.     

Monitoring codling moth (Lepidoptera: Tortricidae) with a four‐component volatile blend compared to a sex pheromone‐based blend

Monitoring adult codling moth, Cydia pomonella (L.), is a crucial component in implementing effective integrated management programmes in apple, Malus domestica Borkhausen. Use of sex pheromone lures to track male populations has been the traditional approach, but their use in orchards treated with sex pheromone for mating disruption (MD) has been problematic. Development of kairomone and kairomone–pheromone combination lures has allowed the catch of female moths and has benefited several aspects of codling moth management through improved spray timings and action thresholds. Recently, a new four‐component volatile blend (4‐K) comprised of pear ester, (E,Z)‐2,4‐ethyl decadienoate (PE), (E)‐11 4,8‐dimethyl‐1,3,7‐nonatriene, all isomers of pyranoid linalool oxide and acetic acid (AA) has been characterized that has increased female moth catch threefold versus any previous blend. Field trapping studies were conducted to compare moth catches in traps baited with 4‐K versus the use of sex pheromone, (E,E)‐8,10‐dodecadien‐1‐ol (PH) in combination with PE and AA. Trials were conducted in orchards left either untreated, or treated with PH or PH + PE. Traps baited with 4‐K and 4‐K + PH lures caught significantly more females than traps baited with PH + PE + AA lures. Traps baited with 4‐K + PH lures caught significantly more total moths than traps baited with PH + PE + AA lures in all three orchards. Adding a PH lure to traps with the 4‐K lure did not affect female catch, but significantly increased male and total moth catches. These studies demonstrate that codling moth can be trapped effectively in apple under MD without the use of sex pheromone lures. The significant increase in female codling moth catch with the 4‐K lure suggests that efforts to improve spray timings and action threshold determinations as well as mass trapping might be enhanced with this new lure.     

Application of synthetic sex pheromone for management of diamondback moth, Plutella xylostella, in cabbage

Over a 2-year period field trials were conducted to assess the potential to disrupt mating ofPlutella xylostella (L.) using a commercial rope formulation of a 70:30 mixture of (Z)-11-hexadecenal and (Z)-11-hexadecenyl acetate, two components of the sex pheromone of the female. Screened field cages were placed into blocks of cabbage which were either treated with the pheromone or left untreated. Different densities of P. xylostella pupae were placed into each cage and then larval and pupal counts were made of the subsequent generation. In addition, sentinel females at mating stations were placed in each cage to assess the influence of the pheromone on the ability of males to locate and mate with females. Likewise, we used pheromone traps to assess whether the pheromone treatment influenced the ability of males to locate a pheromone source. In both years larval and pupal populations, produced as a result of the original inoculation, did not differ between pheromone-treated and untreated fields. The effect of pheromone treatment on larval and pupal numbers did not change with changes in inoculated P. xylostella density, however, the density of P. xylostella released caused significant differences in the density of the subsequent generation. No significant differences were detected between the number of sentinel female adult P. xylostella that successfully mated in pheromone-treated fields compared with untreated fields. Significant differences in the numbers of male P. xylostella caught in pheromone-baited traps occurred between pheromone-treated and untreated fields in the first trial of 1993, and in the first trial in 1994 but not in the second trial. Such differences are often thought of as indications of mating disruption, although our other data presented in this study and reports from other studies indicate this is not always the case. Previous studies on mating disruption of P. xylostella in larger scale field tests have been performed but the results have been variable and often ambiguous. Overall, our results indicate that mating disruption of P. xylostella with the present technology does not appear to work even under the very controlled situations which we utilized to eliminate insect movement between plots.     

Evaluation of extended-season mating disruption of the Oriental fruit moth Grapholita molesta (Busck) (Lep., Tortricidae) in apples

Abstract:  Oriental fruit moth Grapholita molesta (Busck) (Lep., Tortricidae) has recently become a key pest of apples throughout the eastern USA. Pheromone-mediated mating disruption of Oriental fruit moth was successfully used in North Carolina apple orchards in the past few years. However, low levels of late-season fruit damage occurred in some orchards treated in late May with hand-applied pheromone dispensers because of inadequate dispenser longevity. To investigate alternative pheromone application schedules for extended mating disruption control, the following pheromone treatments were compared with conventional insecticides in Henderson County (NC) in 2002: late May application of hand-applied dispensers; late June application of hand-applied dispensers; late May application of hand-applied dispensers supplemented with a late August application of sprayable pheromone dispensers; late May application of hand-applied dispensers which have a longer activity period; and conventional insecticides as a control. All treatments were sprayed with an insecticide at petal fall in late April for thinning and for control of the first generation Oriental fruit moth adults. Pheromone trap catches were significantly reduced in all mating disruption blocks compared with conventional insecticide blocks. Among pheromone treatments, the highest trap captures were recorded in the delayed hand-applied dispenser treatment in June before treatment. However, the mean percentage fruit damage did not vary with timing of application of hand-applied dispensers and the type of pheromone dispenser used. Clearly, the combination of each mating disruption treatment with insecticide application against first generation Oriental fruit moth was as effective as the conventional insecticide treatment under moderate population pressure.     

Mating disruption barriers in pome fruit for improved control of oriental fruit moth Grapholita molesta Busck (Lep., Tortricidae) in stone fruit under mating disruption

Oriental fruit moth (OFM) Grapholita molesta Busck (Lep., Tortricidae) is a very important pest in commercial orchards in Victoria, Australia. Pheromone‐mediated mating disruption (MD) applied in stone fruit orchards successfully controlled OFM populations for many years, but damage to shoot tips and fruit at the edge of peach blocks located adjacent to pear blocks under insecticide treatments has become problematic. To improve protection of stone fruit against edge damage and outbreaks of OFM, all orchards were treated with sex pheromone dispensers for MD on an area‐wide basis. Area‐wide MD treatment, including all pome and stone fruit orchards in a discrete area, successfully controlled edge infestations of OFM, but was expensive. To reduce the cost of OFM control, sex pheromone dispensers for MD were applied as barrier treatments to 54–60 m of neighbouring pears adjacent to peaches under MD. Detailed monitoring of the OFM population, shoot tip and fruit damage assessments indicated that application of MD barriers on pears during two consecutive seasons provided sufficient control of OFM on peaches. This MD barrier treatment was able to reduce the number of OFM caught in all experimental peach blocks, with damage to shoot tips and fruit giving similar results to MD treatment of the whole neighbouring pear block. Extending the MD treatment area for 54–60 m into the neighbouring pear block significantly reduced the edge damage in MD‐treated peaches in the first season and almost eliminated OFM damage in the second season.     

Mating disruption of the ambrosia beetle Megaplatypus mutatus in poplar and hazelnut plantations using reservoir systems for pheromones

Megaplatypus mutatus (Chapuis) (Coleoptera: Curculionidae: Platypodinae) is an ambrosia beetle native to South America, but it has recently been introduced into Italy and represents a serious problem in commercial poplar and fruit tree plantations. Male M. mutatus emit a sex pheromone composed of (+)‐6‐methyl‐5‐hepten‐2‐ol [(+)‐sulcatol], 6‐methyl‐5‐hepten‐2‐one (sulcatone), and 3‐pentanol. We performed three field trials of mating disruption of M. mutatus in hazelnut and poplar plantations in Argentina and Italy. To perform these tests, we made plastic pheromone reservoir‐type dispensers for sulcatol, sulcatone, and 3‐pentanol with zero‐order kinetics that were deployed in the field during the female flight period. The number of galleries where mating took place was significantly higher in control than in treated areas, indicating that pheromone application had interfered with female behavior and male localization. Because damage reduction was >56% in both countries, these results demonstrate the potential for the strategy of pheromone‐mediated mating disruption of M. mutatus in commercial poplar and hazelnut plantations. Also, our study provides the first evidence for successful pheromone‐mediated mating disruption in a forest beetle.     

Sprayable pheromone for controlling the North American grape berry moth by mating disruption

Abstract 1 Sex pheromone‐mediated mating disruption can be used to provide economic control of the North American grape berry moth in commercial vineyards. Controlled release devices that use a plastic tube or polymer to regulate the emission of pheromone have been registered for use in Canada for controlling this pest. These dispensers require manual application, whereas a newly developed microencapsulated formulation can be applied using a vineyard airblast sprayer. 2 The efficacy of 3M Sprayable Pheromone was compared with the efficacy of Isomate^® GBM pheromone dispensers and organophosphorus insecticide for controlling the grape berry moth during the 1997 and 1998 growing seasons. Two application schedules of sprayable pheromone were tested during 1997 and two formulations of sprayable pheromone were tested during 1998. The mating disruption efficiency of the pheromone treatments was compared using pheromone‐baited traps and the efficacy of the pheromone and insecticide treatments was compared by inspecting grape clusters for feeding injury caused by grape berry moth larvae. 3 The estimated mating disruption efficiency of the pheromone treatments ranged from 67 to 100%. There was no difference in the efficiency of the two application schedules of 3M Sprayable Pheromone during 1997. The estimated efficiency of Isomate^® GBM was greater than that of 3M Sprayable Pheromone during the first two flights of 1997. During 1998, the estimated efficiency of 3M Sprayable Pheromone and Isomate^® GBM was similar. 4 The average percentage of grape clusters with grape berry moth feeding injury was greater in the border than in the interior zone on 13 ocassions, and greater in the interior zone than in the border zone of experimental plots on six of the 72 occasions when clusters were inspected during the 2‐year study. 5 The average percentage of grape clusters with feeding injury was similar in plots treated with 3M Sprayable Pheromone, Isomate^® GBM and insecticide during both years of the study. There was no difference in feeding injury in plots treated with 3M Sprayable Pheromone and Isomate^® GBM, despite the greater estimated mating disruption efficiency of Isomate^® GBM. 6 The use of sprayable pheromone may have several operational and cost advantages compared with a hand‐applied dispensing system such as Isomate^® GBM.     

Sex pheromone production and perception in the mating disruption-resistant strain of the smaller tea leafroller moth, Adoxophyes honmai

Mating disruption is an environmentally safe plant protection strategy that uses a synthetic copy of an insect pheromone to interfere with sexual communication and hence reproduction. To date, a number of pest moths have been controlled with applications of formulated pheromones as mating disruptants. Recently, however, the first example of resistance to mating disruption was documented in one of the major tea pests in Japan, the smaller tea leafroller moth, Adoxophyes honmai Yasuda (Lepidoptera: Tortricidae). To avoid other such cases, it is important to elucidate the mechanism(s) by which the disruptant lost its effectiveness. To this end, we imposed further selection by rearing field‐collected resistant insects with a synthetic pheromone in the laboratory. After more than 70 generations of selection, a strain with quite strong resistance was established, males of which could find and copulate with their mates even in the presence of 1 mg l^?1 of disruptant. Although the mating ability of this strain was greatly increased, the composition and blend ratio of the sex pheromone produced and emitted by females were not obviously changed in comparison with those of females sensitive to mating disruption. However, male response to the pheromone blend was markedly broadened after selection so that resistant males could locate a synthetic pheromone source even when it lacked a pheromone component that is normally necessary for attraction. Males capable of locking onto off‐ratio pheromone blends may be better able to find calling females in pheromone‐treated environments than narrowly tuned males because of greater capability of overcoming sensory imbalance.     

Effects of SPLAT® GM sprayable pheromone formulation on gypsy moth mating success

Several integrated pest management programs rely on the use of mating disruption tactics to control insect pests. Some programs specifically target non‐native species, such as the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae). We evaluated SPLAT^® GM, a new sprayable formulation of the gypsy moth sex pheromone disparlure, for its ability to disrupt gypsy moth mating. The study was conducted in 2006, 2007, and 2008 in forested areas in Virginia, USA. Mating success of gypsy moth females was reduced by >99% and male moth catches in pheromone‐baited traps by >90%, in plots treated with SPLAT^® GM at dosages ranging from 15 to 75 g of active ingredient (a.i.) ha^?1. Dosage‐response tests conducted in 2008 indicated that SPLAT^® GM applied at a dosage of 7.5 g a.i. ha^?1 was as effective as a 15 g a.i. ha^?1 dosage.