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Pheromone Traps (pheromone + trap)
Selected AbstractsDispersal capacity in the Mediterranean corn borer, Sesamia nonagrioidesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2004M. Eizaguirre Abstract Corn (Zea mays L.) borers are the primary target of Bacillus thuringiensis Berliner (Bt) transgenic maize. Management of corn borer resistance to Bt requires information on larval and adult dispersal capacities, a feature that is particularly unknown in Sesamia nonagrioides Lefèbvre (Lepidoptera: Noctuidae), the most damaging corn borer in Spain. Larval dispersal was studied over a 3 year period by infesting plants with egg masses and dissecting the neighbouring plants 7, 14, and 32 days later to measure larval dispersal at several ages. The number and age of larvae were recorded in the dissected plants. Only mature larvae dispersed in significant numbers; they moved at least to rows adjacent to those containing the infested plant, and down the row five plants. The percentage of larvae that dispersed from the infested plant was density-dependent. Adult dispersal was studied with directional light and pheromone uni-traps over 5 and 3 year periods, respectively. Directional light traps were placed in the margins between Bt and non-Bt maize fields, half oriented towards each of the two kinds of maize field. Pheromone traps were placed in the Bt and non-Bt fields at increasing distances (0,100 m) from the border. The numbers of males and females caught in directional light traps were not different in traps oriented towards Bt or non-Bt fields, but the number of males caught in the third flight in Bt fields was lower than in non-Bt fields. These results suggest that males from adjacent Bt and non-Bt fields mate indiscriminately with females emerging in any of the two kinds of maize fields. However, male movement in the third flight may not be sufficient to randomly distribute males between the two fields. [source] Reduction in an almond moth Ephestia cautella (Lepidoptera: Pyralidae) population by means of mating disruptionPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 10 2006Camilla Ryne Abstract Pheromone-based mating disruption of the almond moth (Ephestia cautella) (Walk.) (Lepidoptera: Pyralidae) was carried out in a chocolate factory in Sweden. Population monitoring was conducted with pheromone-baited traps and water traps. Pheromone traps showed a 94% catch reduction, and monitoring with water traps showed a significant decrease in total catch (5.0 and 1.6 individuals per trap per week before and during treatment respectively). The significance of the results was tested by fitting the observed data to a first-order autoregressive model. This made it possible to test the data with a 95% confidence interval, comparing trap catches before mating disruption treatment with trapping data during the experiment. It is suggested that this statistical approach may be used more frequently in mating disruption experiments where it is extremely difficult to control external factors and therefore equally difficult to use a comparable control plot to evaluate the treatment. Copyright © 2006 Society of Chemical Industry [source] Behaviour of male pine sawflies, Neodiprion sertifer, released downwind from pheromone sourcesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2000Fredrik Östrand Abstract This study investigated the behaviour of male European pine sawflies, Neodiprion sertifer Geoffroy (Hym., Diprionidae), that were released and observed downwind from pheromone traps baited with 100 ,g of the sex pheromone, (2S,3S,7S)-3,7-dimethyl-2-pentadecyl acetate. Releases were done at three distances; either at 5 m from one trap, or at 50 or 200 m from five traps, placed in a line perpendicular to the current wind direction. As control, males were released identically but without any pheromone source present. The behaviour of the males prior to take-off was studied. A total of 1729 males were released, and 80% of them took flight. Males took off significantly faster in the presence of pheromone. Grooming was significantly more frequent in presence of pheromone compared with control. In all pheromone experiments significantly more males displayed grooming, wing fanning and take-off towards the wind compared with the control. Weather data was simultaneously collected at the study site. Wing fanning was negatively correlated with wind speed. Grooming was not influenced by wind speed. Reduced levels of incoming short-wave radiation lowered the take-off frequency significantly. Pheromone-induced behaviour in diprionids seems to be less distinct than in other insects, e.g., Lepidoptera. [source] Effect of weather factors on populations of Helicoverpa armigera moths at cotton-based agro-ecological sitesENTOMOLOGICAL RESEARCH, Issue 1 2009Ghulam Mustafa AHEER Abstract Pheromone trapping was used to monitor populations of the moth Helicoverpa armigera at five cotton-based agro-ecological sites , river, vegetable, orchard, forest and clean cultivation (areas under only cotton cultivation) , in the Bahawalpur district, Pakistan. Three locations at each site were chosen and three pheromone traps at each location were installed in cotton fields. Moth catches were recorded at 15,20 day intervals from 24 October 2004 to 19 December 2006. In 2004, the river sites showed the maximum trapped population of H. armigera (0.22/trap) followed by 0.165 per trap at the vegetable sites. Orchard, clean cultivation and forest sites had zero moth catches. In 2005, the river sites again showed the highest trapped population (0.57/trap), followed by clean cultivation (0.45/trap), vegetable (0.44/trap), orchard (0.40/trap) and forest (0.29/trap). The moths appeared during July to December and March to May. In 2006, sites showed non-significant difference, with a population range of 0.47 to 0.97 moths per trap. On average, river sites peaked at 0.49 per trap, followed by vegetable (0.38), clean cultivation (0.47), orchard (0.35) and forest (0.25) sites. The peak was observed on 3 April 2006, and moths appeared during February to July and October to December. The minimum temperature in river, forest and clean cultivation sites; the maximum temperature in orchard sites; and the average temperature in river, orchard, forest and clean cultivation sites showed significant positive correlations with trapped moth populations. Relative humidity showed significant negative correlation with population at the orchard sites in 2005. All weather factors during 2004 and 2006 showed non-significant correlations with the moth populations. No model was found to be best fit by multiple linear regression analysis; however, relative humidity, minimum temperature, maximum temperature, minimum temperature and maximum temperature contributed 8.40, 10.23, 2.43, 4.53 and 2.53% to the population fluctuation of the moth at river, vegetable, orchard, forest and clean cultivation sites, respectively. [source] Difference in the time of mating activity between host-associated populations of the rice stem borer, Chilo suppressalis (Walker)ENTOMOLOGICAL SCIENCE, Issue 3 2006Hideki UENO Abstract Mating activities of the rice stem borer, Chilo suppressalis, were compared between rice- and wateroat-feeding populations, and two potential temporal factors that may act as reproductive barriers were examined. Seasonal data of the number of moths attracted to pheromone traps showed that the peak of emergence at the rice field was approximately 10 days earlier than that at the wateroat vegetation in the first flight season, although there was a broad overlap of emergence at the two locations. Both field observations and a laboratory experiment showed that moths from the rice field started mating earlier than those from the wateroat vegetation. However, whereas the difference was distinctive in the laboratory experiment, mating activity at the wateroat vegetation shifted significantly to an earlier time phase than that observed in the laboratory. Body size data showed that the male moths attracted to the pheromone traps at the wateroat vegetation were significantly larger than those at the rice field, suggesting that the traps at the two locations mainly attracted moths originating from different host plants. However, pheromone-trapped males at the rice field were significantly larger than those reared from overwintering samples. These results support the idea that males from the wateroat vegetation migrate to the rice field. The differences in seasonal and temporal mating activity and their effects on development of reproductive isolation between host-associated populations are discussed. [source] Spatial and temporal variability in host use by Helicoverpa zea as measured by analyses of stable carbon isotope ratios and gossypol residuesJOURNAL OF APPLIED ECOLOGY, Issue 3 2010Graham Head Summary 1.,A high dose/refuge strategy has been adopted in the USA to manage the risk of Bacillus thuringiensis (Bt) resistance in target pests such as the cotton bollworm (CBW), Helicoverpa zea (Boddie) in transgenic Bt cotton Gossypium hirsutum L. Structured refuges, consisting of non-Bt cotton, have been a mandated part of this strategy to produce non-selected insects that are temporally and spatially synchronous with insects from the Bt crop, diluting Bt resistance alleles through mating. However, the bollworm is highly polyphagous and exploits a large number of crop and weedy hosts concurrently with Bt cotton. 2.,A study was carried out in five major US cotton-producing states during 2002 and 2003 using the ratios of 13C to 12C in bollworm moths to estimate the proportions of the population originating from C3 or C4 plants. A separate study measured gossypol residues in moths from four states in 2005 and 2006, enabling the identification of moths whose natal hosts were cotton rather than other C3 hosts. 3.,C4 hosts served as the principal source of bollworm moths from mid-to-late June to early September, depending on the state. Beginning in late August/early September and lasting 1,4 weeks, the majority of moths exhibited isotopic compositions characteristic of C3 hosts. During this period, however, the minimum percentage of moths that developed as larvae on C4 hosts was typically >25%. By mid-September and through October and November, the majority of the bollworm population exhibited C4 isotopic compositions. 4.,Between late June and early August, cotton-derived bollworm moths (moths with gossypol residues) comprised <1% of moths in all states, and remained below this level throughout the season in North Carolina. In other states, cotton-derived moths increased between early August and early September to peak at an average of 19·1% of all moths. 5.,Synthesis and applications.,Data on 13C/12C ratios and gossypol residues in CBW moths were used to assess the importance of structured non-Bt cotton refuges for the management of Bt resistance risk in H. zea. Weekly estimates of bollworm breeding on cotton, C3 plants other than cotton and C4 plants showed that, throughout the season, the majority of bollworm moths caught in pheromone traps adjacent to cotton fields did not develop as larvae on cotton. This result implies that management practices in cotton such as the use of structured cotton refuges will play a relatively minor role , particularly compared with maize Zea mays L. , in managing potential resistance to Bt cotton in populations of the CBW in the US Cotton Belt. [source] Season-long mating disruption of citrus leafminer, Phyllocnistis citrella Stainton, with an emulsified wax formulation of pheromoneJOURNAL OF APPLIED ENTOMOLOGY, Issue 6 2010L. L. Stelinski Abstract The citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), is a major worldwide pest of citrus. Larval feeding by this insect facilitates proliferation of citrus bacterial canker, Xanthomonas axonopodis pv. citri. Herein, we describe a season-long disruption trial of P. citrella with a newly developed, emulsified wax dispenser of pheromone (SPLAT-CLMTM). A formulation containing a 3 : 1 blend of (Z,Z,E)-7,11,13-hexadecatrienal:(Z,Z)-7,11-hexadecadienal at a 0.2% loading rate of active ingredient by weight and deployed twice per season (24 weeks total) at 490 g of formulation/ha caused season-long disruption of male moth catch in pheromone traps as well as reduced leaf infestation. Analysis of pheromone release from dispensers by gas chromatography revealed that effective disruption of P. citrella occurred at a deployment rate of 126 ,g of (Z,Z,E)-7,11,13-hexadecatrienal/ha/h. Direct observation of moth behaviour in the field suggested that disruption by this formulation occurred by a non-competitive mechanism. A formulation of the 3 : 1 attractive blend at a 0.02% pheromone loading rate caused only 2,6 weeks of disruption per deployment and did not reduce leaf infestation during mid and end of the season evaluations. A formulation containing 0.2% of (Z,Z)-7,11-hexadecadienal alone and deployed at 490 g/ha caused 6,7 weeks of moth disruption to pheromone traps and did not prevent leaf infestation, while an identical formulation loaded with 0.02% (w/w) of (Z,Z)-7,11-hexadecadienal alone had no effect on P. citrella orientation to pheromone traps. The SPLAT formulation evaluated herein appears to be an excellent release device for (Z,Z,E)-7,11,13-hexadecatrienal given that approximately 100 days of steady release occurred following an initial brief (ca. 7 days) burst of higher release. The advantages of SPLAT as a formulation for P. citrella disruption include low cost of manufacturing, biodegradable and weather resistant characteristics, and flowability allowing machine application. Mating disruption should be an effective alternative to insecticides for management of P. citrella and may reduce the incidence of citrus canker. [source] Sampling plan for the coffee leaf miner Leucoptera coffeella with sex pheromone trapsJOURNAL OF APPLIED ENTOMOLOGY, Issue 6 2008T. Bacca Abstract The population density of the coffee leaf miner Leucoptera coffeella (Guérin-Méneville & Perrottet) (Lep., Lyonetiidae) can be estimated using pheromone traps in coffee fields as male capture reflects this pest damage based on previous correlational study. However, the spatial distribution of pheromone traps and their density are necessary to optimize the sampling procedure with pheromone traps. Therefore, the objectives of the present study were to determine the pheromone trap density required per hectare to sample coffee leaf miner populations and to determine the spatial distribution of the males of this pest species. The males were sampled every 8 days in 12 consecutive evaluations. Taylor's power law and frequency distributions were used to recognize the distribution of the male capture data, which followed a negative binomial distribution. A common K was obtained, allowing the establishment of a single conventional sampling plan for the 12 fields investigated. The adjusted sampling plan requires eight traps in an area of 30 ha for a 25% precision error. Kriging-generated maps allowed the simulation of male captures for 8, 12 and 20 traps per 30 ha and the results were compared with those obtained with absolute sampling resulting in R2 -values of 0.30, 0.57 and 0.60 respectively. The traps were able to identify the more highly infested areas within the field and are a precise and efficient tool for sampling populations of L. coffeella. [source] Expansion of pea cropping increases the risk of pea moth (Cydia nigricana; Lep., Tortricidae) infestationJOURNAL OF APPLIED ENTOMOLOGY, Issue 3 2006E. Huusela-Veistola Abstract:, The pea moth (Cydia nigricana) is a host-specific pest of pea (Pisum sativum). In Finland, the combine-harvested field pea is grown on an area totalling 5000 ha. However, the area under pea cropping may increase substantially if pea replaces soya bean as a protein source for animal feed, which may result in pest and disease problems. In this study, the risk of pea moth infestation is evaluated by modelling field survey data. The observations were made in 2002 and 2003 at 93 and 90 pea fields, respectively, in south-western Finland. The choice of the experimental fields was based on pea cropping data from 1997 to 2001 and included regions of both intensive and less intensive pea cultivation. The occurrence of pea moth adults in the fields was assessed with pheromone traps, and the percentage of damaged pods and pea seeds in each field was determined. The number of pea moths in pheromone traps and the percentage of damaged seeds increased linearly when the area under pea cropping during the previous year (within a 4-km distance) increased, and decreased exponentially when the distance to the nearest pea field in the previous year increased. Furthermore, the percentage of damaged pods and seeds was higher in organic than in conventional fields. Expansion of pea cropping would change the spatial distribution of pea fields, thus affecting the risk of pea moth infestation. An increase in the scale and frequency of pea cropping increases the need for plant protection. [source] A practical method for predicting the short-time trend of bivoltine populations of Ips typographus (L.) (Col., Scolytidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2006M. Faccoli Abstract:,Ips typographus is the main spruce pest of European forests. In most areas of the Italian Alps there are two generations per year; overwintering adults fly in May looking for trees suitable for breeding, their offspring emerge in summer, 7,8 weeks after tree colonization, and the adults of the second generation emerge in spring of the following year after overwintering under the bark or in the litter. A long-term population monitoring was carried out in north-east Italy with the aim at developing a prediction model able to estimate the population density of the following year. Between 1996 and 2004, pheromone traps monitored populations of I. typographus annually. Monitoring lasted 4 months (May,August), with replacement of pheromone dispensers after 8 weeks. Insects trapped before dispenser change were called ,spring captures' (May,June), and included both overwintering and re-emerging adults. Beetles caught after dispenser change were called ,summer captures' (July,August), and included the adults of the first generation. The results show a high positive correlation between the ratio of summer and spring captures of one year (Summerx/Springx), and the ratio of total captures of the following year (Yx+1) and those of the current year (Yx) (Yx+1/Yx). Summerx/Springx lower than 0.62 indicate decreasing populations in the following year (Yx+1/Yx <1), whereas Summerx/Springx higher than 0.62 indicate increasing populations (Yx+1/Yx >1). The applicability of the model in the study of I. typographus risk of outbreak and in the forest management is discussed. The prediction of the short-time trend of the population allows assessing its density in the following year, and therefore the risk of outbreak. [source] Sex pheromone for monitoring flight periods and population densities of the pine sawfly, Diprion jingyuanensis Xiao et Zhang (Hym., Diprionidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 7 2005Z. Zhang Abstract:, The pine sawfly, Diprion jingyuanensis Xiao et Zhang, is a serious pest of Chinese pine (Pinus tabulaeformis Carr.) in the northern parts of China. The general biology of this recently described sawfly species is little known and in the present study we used a synthetic pheromone to monitor its flight period and to evaluate the possibility to use pheromone traps as a tool for estimating and predicting population densities. The attractant pheromone of D. jingyuanensis is (1S,2R,6R)-1,2,6-trimethyldodecyl propionate and in this study we used a four-isomer threo-mixture containing the active attractant. Both doses tested, 1 and 2 mg/trap, revealed the same seasonal flight pattern, the higher dosage demonstrating more clear flight peaks. The first flight peak of D. jingyuanensis occurred in mid-June during all 3 years, 1997,1999, and in 1997 and 1998 a second flight peak was also recorded in mid-July. The flight period was similar in time for populations located at higher (1400 m) and lower altitude (1100 m), from early June to late July or early August. Temperature was the main weather factor-affecting trap catches. Diurnal flight activity began at 9.00, peaked at 13.00 and lasted until 20.00. A series of tests with traps in different positions within stands and trees were conducted and the results demonstrated the importance of standardizing the trapping protocol in population monitoring studies. By using traps with 2 mg baits it is possible to detect sawfly occurrence at very low population densities, not detectable by other means. Strong positive correlations between trap catch and relative population density were found in 2000 and 2001, but not in 1998, when only few sites were monitored and the population was in a decreasing phase. The results are promising for future large-scale use of pheromone-based monitoring of D. jingyuanensis. [source] Ips typographus (L.) pheromone trapping in south Alps: spring catches determine damage thresholdsJOURNAL OF APPLIED ENTOMOLOGY, Issue 4 2004M. Faccoli Abstract:,Ips typographus is one of the major forest pests in the Italian Alps. From 1996, populations of I. typographus in Friuli-Venezia Giulia region (NE Italy) have been permanently monitored in areas of outbreak by using pheromone traps. At the same time, damage caused by the insect was estimated annually. Preliminary analysis of the data (1996,2002) reveals some interesting information: (i) the flight activity of I. typographus is very extended and occurs over a period of about 4 months (May to August); (ii) there is a high correlation between mean captures per trap and annual damage; (iii) there is a high correlation between spring captures (May to mid-June) and total captures (May to August), and between spring captures (May to mid-June) and annual damage. The correlation between spring captures and damage allows the determination of a reliable risk-damage threshold (about 5000 beetles/trap, in spring), reducing at the same time, the monitoring period and the general costs. [source] Global warming affects phenology and voltinism of Lobesia botrana in SpainAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 2 2010Daniel Martín-Vertedor 1Climate change is promoting alterations of a very diverse nature in the life cycle of an array of insect species, including changes in phenology and voltinism. In Spain, there is observational evidence that the moth Lobesia botrana Den. & Schiff. (Lep.: Tortricidae), a key vine pest that is usually trivoltine in Mediterranean latitudes, tends to advance spring emergence, displaying a partial fourth additional flight, a fact that is potentially attributable to global warming. 2To verify this hypothesis, local temperatures were correlated with L. botrana phenology in six vine-growing areas of southwestern Spain during the last two decades (1984,2006) by exploiting the database of flight curves obtained with sexual pheromone traps. The dates of second and third flight peaks of the moth were calculated for each area and year and then correlated with both time (years) and local temperatures. 3The results obtained demonstrated a noteworthy trend towards local warming (as a result of global warming) in the last two decades, with mean increases in annual and spring temperatures of 0.9 and 3.0°C, respectively. Therefore, L. botrana phenology has significantly advanced by more than 12 days. Moreover, the phenological advance contributed to increased moth voltinism in 2006 by promoting a complete fourth additional flight, a fact that has never been reported previously to our knowledge in the Iberian Peninsula. 4The potential impact of an earlier phenology and increased voltinism in L. botrana is discussed from an agro-ecological perspective. [source] Effect of fallows on population dynamics of Cosmopolites sordidus: toward integrated management of banana fields with pheromone mass trappingAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 2 2010Béatrice Rhino 1The banana weevil Cosmopolites sordidus Germar (Coleoptera: Curculionidae) is the most serious pest of banana and plantain in most production areas, including the West Indies. 2During a period of 2 years, we assessed the efficacy of a pheromone mass-trapping control strategy of C. sordidus in field conditions in Guadeloupe at different cropping stages, both in sanitation fallows and in different ratoon banana crops. 3In the fallows, catches peaked 3 months after beginning trapping and then decreased to zero after 9 months. By contrast, for the new plantations, the catches of C. sordidus increased after the 11th month and, in the older banana fields, there was no decrease in C. sordidus catches. The C. sordidus catches increased in the neighbouring banana plots, whereas they decreased in the fallows, and these catches decreased with the distance from fallow. 4In conclusion, mass trapping with synergized pheromone traps within fallows should allow better sanitation of banana plantations. Yet, within the farms, fallows must not be located next to new plantations to avoid massive damage to the young plants. More generally, the present study emphasizes that the control of this insect should be managed at the farm scale and not at the field scale, with special attention being paid to the location of fallows. [source] Distribution and sampling of adults of Rhabdoscelus obscurus (Boisduval) (Coleoptera: Curculionidae) and their damage in sugarcaneAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 3 2001Mohamed N Sallam Abstract Sampling statistics and spatial distribution were determined for adults of the sugarcane weevil borer, Rhabdoscelus obscurus, and for their damage in cane fields. Insect counts were obtained from split-cane traps and pheromone-baited traps. Counts of damaged internodes per stalk were also obtained from the same plots. Density and variance estimates of the three variables were fitted to Taylor's power law, which provided significant regression in all three cases (R2 > 0.86). Spatial distributions of weevil borers as well as damage symptoms were clumped, which may explain the patchy nature of infestation in cane. Analysis of within-plant distribution of damage showed that older internodes at the base of the stalk were more frequently infested than younger ones. Optimal sample sizes were determined for split-cane and pheromone traps and damaged stalks. Sequential sampling plans and fixed-precision level stop lines for the three parameters were also determined. [source] | ||||||||||