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Insect populations in temperate climates can show seasonal differences in demographic rates. Extreme high‐temperature events (EHTs) are increasing in frequency across all seasons. These may, in turn, disrupt insects' season‐specific demographic strategies. However, whether insect populations respond to EHTs in a season‐specific fashion is not known, but may be critical for forecasting their responses to climate change. We conducted a series of common garden experiments measuring the inherent vital rates of spring, summer, and autumn cohorts of a global nonmigratory pest, the oriental fruit moth (Grapholita molesta), under constant mild temperatures, EHT exposures at different life stages, and short‐term heat hardening followed by EHT exposure at different life stages. We simultaneously conducted a 4‐year survey of G. molesta in orchards to link our experimental results to observed population dynamics in the field. We encountered intrinsic variation in vital rates and reproductive traits among seasonal cohorts, such that summer cohorts had higher intrinsic population growth rates but smaller eggs than spring and autumn cohorts. Moreover, these responses varied among the life stages to which the EHT was applied. Pre‐acclimation via heat hardening did not strongly affect these results but did slightly increase growth rates when applied to late‐stage larvae. These results were qualitatively recovered in natural population time series, with moderate EHTs enhancing population growth in the spring and reducing it in autumn. Our results underscore the importance of climatic seasonality in shaping season‐specific thermal responses to EHTs among ectotherms. Season‐specific EHT responses can potentially enhance growth of weak spring cohorts and depress the growth of autumn cohorts failing in dormancy, thereby contributing to insects' annual population persistence. Our study helps clarify how a deeper understanding of season and life‐stage‐specific heat responses can enable a more informed forecasting and management of multivoltine insect populations under climate change. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

BACKGROUND: Grapholita molesta is an important and harmful fruit pest worldwide, with widespread feeding hosts. Trypsin, an indispensable hydrolytic digestive protease in the insect gut, is crucial in digestion, growth and development. We analyzed the characteristics of the trypsin‐encoding genes, screened for the optimal dose of RNAi mediated by nanocarriers, and investigated various indices of larval growth and development of G. molesta. RESULTS: Gut content (GC) and RNase A degraded double‐stranded RNA (dsRNA), with a faster degradation rate at higher concentrations. Star polycation (SPc) nanomaterials protected dsGFP from degradation by anion–cation binding and did not migrate through agarose gel. The key conserved motifs of the trypsin‐encoding genes were similar, exhibiting high homology with those in other lepidopteran insects. An interference efficiency of ≈70% was achieved with SPc nanomaterial‐mediated RNA interference with 0.05 μg dsRNA. The efficiency of continuous interference was stable. Trypsin activity, body weight of 8‐day‐old larvae, pupal weight and emergence rate were significantly reduced, and the larval stage was significantly prolonged. CONCLUSION: The investigated trypsin gene is a key target gene in the growth and development of G. molesta. We investigated the efficiency and convenience of feeding SPc nanomaterials in a functional study of insects. Our results provide valuable data for the development of efficient trypsin‐targeting pesticides. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The oriental fruit moth, Grapholita molesta, is one of the most destructive orchard pests worldwide. Due to its behavior of boring into twigs and fruits, controlling the pest at the larval stage using insecticides is challenging. We studied the enemy species at the larval stage of G. molesta from seven fruit-growing areas by sampling peach shoots and fruits bored by its larvae. The occurrence and biological characteristics of the dominant enemy were verified using field investigation and laboratory experiments. The results showed that the dominant enemy species of larval G. molesta was identified as Therophilus festivus. The larval, cocoon, and pupal stages of T. festivus could not survive at 35 °C. The developmental durations of these three stages at 20 °C were significantly longer than those at 25 °C and 28 °C. Consecutive years of investigation in Xinxiang, China, indicated that T. festivus can parasitize G. molesta larvae collected at each generation. The parasitism rates in June (45.16%), July (63.50%), and August (48.37%) were significantly higher than those in April (15.27%). Most field research in China has focused on the release of parasitoids to control G. molesta eggs. Our study establishes a foundation for the control of G. molesta larvae using T. festivus. [ABSTRACT FROM AUTHOR]

Simple Summary: The plum fruit moth, Grapholita funebrana Treitschke (Lepidoptera, Tortricidae), is an important agricultural pest that seriously affects fruit production across the Palearctic region. In this study, for the first time, we predict the potential global distribution of this pest using an ensemble species distribution model. The distribution range predicted, especially for those regions with highly suitable habitats for this moth in parts of East Asia and Europe, indicates a high risk of G. funebrana outbreaks and the accompanying massive economic losses, especially in plum and apricot production, highlighting the necessity of pest management. In the United States of America (USA) and Japan (for which G. funebrana distributions have not previously been recorded), especially in areas that are highly suitable for this moth, monitoring and quarantine measures should be strengthened to prevent the colonization of this pest and its subsequent wide dispersal. The plum fruit moth, Grapholita funebrana Treitschke, is one of the most significant borer pests, often causing huge economic losses in fruit production. However, the potential distribution range of this economically important pest is still poorly understood. For this study, we simulated an ensemble species distribution model to predict the spatiotemporal distribution pattern of G. funebrana at a global scale. The results show that the suitable habitats for this moth, under current environmental conditions, are mainly distributed in Europe; East Asia, including China and Japan; Central Asia; and some parts of America. In future projections, the suitable habitats are predicted to generally expand northward, while the suitable area will remain unchanged overall. However, the area of highly suitable habitat will decrease to only 17.49% of that found under current conditions. None of the nine factors used were revealed to be predominant predictors in terms of contributing to the model, suggesting that the integrated effects of these variables shape G. funebrana's distribution. In this study, the distribution range that has been predicted, especially for the regions with a highly suitable habitat, poses a high risk of G. funebrana outbreaks, highlighting the urgency of pest management. Moreover, in the United States of America (USA) and Japan (for which G. funebrana distributions were not previously recorded), especially in areas highly suitable for this moth, monitoring and quarantine measures should be strengthened to prevent the colonization and further dispersal of this pest, as seen with its close relative G. molesta, which has become a cosmopolitan pest species, migrating from its native region (East Asia) to other continents, including the Americas. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: Due to a combination of monandry and promiscuity in Grapholita molesta (Busck), this study investigated the interaction of different adult ages (3, 5, or 7 days) and mating history (unmated or mated) in each sex on the mating selection, development of the reproductive system, and offspring production in the laboratory. The results show that the physiological status of females may be responsible for mating and reproductive decisions, and the physiological status of males may regulate the ranges in behavioral changes. As a species with high reproductive potential, the presence of males accelerated the growth of the G. molesta populations. Our results would provide theoretical data to further understand the reproductive biology of G. molesta in the field. Grapholita molesta (Busck) is a pest of rosaceous fruit plants worldwide. Due to a combination of monandry and promiscuity in G. molesta, the age and mating history of both sexes significantly affected the mating and reproductive success. In this study, the interactions of different ages (3, 5, or 7 days) and mating history (unmated or mated) in each sex on the mating selection, reproductive system, and offspring production were investigated in the laboratory. The results showed that these differences mainly occurred in young females or males, associated with unmated or mated state. Especially, the 3-day-old unmated females were preferred by the 7-day-old males but discriminated against by the 3- or 5-day-old unmated males, whereas the 3-day-old mated males were preferred by the 3-day-old mated or 7-day-old females but discriminated against by the 3- or 5-day-old unmated females. The lengths of the ovarian ducts were affected by age in the unmated females, with the greatest length being found at 7 days old. The size of testes varied with age in the unmated males, being the largest at 3 days old. At 3 days old, the testes size of the unmated males was larger than that of the mated males. The pairing of 5-day-old unmated females × 3-day-old mated males maximized the successful matings. The least productive pairing was 7-day-old unmated females × 5-day-old mated males. The pairing of 5-day-old mated males × 3-day-old mated females had the lowest number of matings and the highest number of offspring. The pairing of 3-day-old mated females × 3-day-old mated males had a high rate of mating success and the most offspring. These results revealed the different roles between females and males because of physiological states in terms of the reproductive biology in G. molesta. [ABSTRACT FROM AUTHOR]

Grapholita molesta (Busck) is an important pest of pear trees. Numerous esters accumulate consistently in mature pear fruits. However, little is known about the effects of single esters from pear fruits at different concentrations on the responses of male and female G. molesta. In this study, the responses of virgin males, virgin females, and gravid females to five esters (3‐methylbutyl acetate, ethyl hexanoate, ethyl butanoate, butyl acetate, and hexyl acetate) of pear fruits at three dosage levels (1, 5 and 10 μg/μL) were investigated using electroantennography (EAG), wind tunnel experiments, and field tests. Our results showed that ethyl butanoate (5 μg/μL) elicited higher EAG responses in virgin females and males than a mixture of all five volatiles, and elicited an equal EAG response to that for the mixture in gravid females, with all responses to ethyl butanoate and the mixture being higher than the response to hexane alone. For upwind flight, ethyl butanoate (5 μg/μL) excited equal moth flight–location behavior in virgin and gravid females to that for the mixture, which were both higher than the response to hexane. For close flight, ethyl hexanoate (5 μg/μL) and 3‐methylbutyl acetate (10 μg/μL) appeared to be the activating compounds, eliciting equal responses from virgin females to that of the mixture, and higher responses of gravid females to that of the mixture, both of which were higher than the responses to hexane. Upwind and close flight responses of virgin males were lower than those of virgin and gravid females. In field trials, we verified that traps baited with ethyl butanoate (5 μg/μL) captured more moths than the other esters. Therefore, from the esters and concentrations tested, we recommend ethyl butanoate (5 μg/μL) for potential use as an attractant for G. molesta in orchards. [ABSTRACT FROM AUTHOR]

Insects that feed on various host plants possess diverse xenobiotic adaptations; however, the underlying mechanisms are poorly understood. In the present study, we used Grapholita molesta, which shifts feeding sites from peach shoots to apple fruits, as a model to explore the effects of shifts in host plant diet on the profiles of cytochrome P450s and the gut bacteria microbiome, as well as their effects on biopesticide adaptation. We found that the sensitivity of the fruit-feeding G. molesta to emamectin benzoate biopesticide was significantly lower than that of the shoot-feeding larvae. We also found that the P450 enzyme activity and the expression of nine cytochrome P450s were enhanced in G. molesta fed on Fuji apples compared to those fed on peach shoots. The survival rates of G. molesta exposed to emamectin benzoate significantly decreased as each of three of four emamectin benzoate-inducted cytochrome P450 genes were silenced. Furthermore, we discovered the gut bacteria dynamics of G. molesta changed with the host shift and the structure of the gut bacteria microbiome was determined by the final diet ingested; additionally, the dysbiosis of the gut microbiota induced by antibiotics could significantly increase the sensitivity to emamectin benzoate. Taken together, our results suggest that the expression of P450s and the composition of the gut bacteria microbiome promote adaptation to emamectin benzoate in G. molesta, providing new insights into the molecular mechanisms underlying xenobiotic adaptation in this notorious pest. [ABSTRACT FROM AUTHOR]

Grapholita molesta is one of the most damaging pests worldwide in stone and pome fruits. Application of chemical pesticides is still the main method to control this pest, which results in resistance to several types of insecticides. Carboxylesterase (CarE) is one of the important enzymes involved in the detoxification metabolism and tolerance of xenobiotics and insecticides. However, the roles of CarEs in insecticides susceptibility of G. molesta are still unclear. In the present study, the enzyme activity of CarEs and the mRNA expression of six CarE genes were consistently elevated after treatment with three insecticides (emamectin benzoate, lambda‐cyhalothrin, and chlorantraniliprole). According to spatio‐temporal expression profiles, six CarE genes expressed differently in different developmental stages, and highly expressed in some detoxification metabolic organs. RNAi‐mediated knockdown of these six CarE genes indicated that the susceptibility of G. molesta to all these three insecticides were obviously raised after GmCarE9, GmCarE14, GmCarE16, and GmCarE22 knockdown, respectively. Overall, these results demonstrated that GmCarE9, GmCarE14, GmCarE16, and GmCarE22 play a role in the susceptibility of G. molesta to emamectin benzoate, lambda‐cyhalothrin, and chlorantraniliprole treatment. This study expands our understanding of CarEs in insects, that the same CarE gene could participate in the susceptibility to different insecticides. [ABSTRACT FROM AUTHOR]

Grapholita molesta is one kind of serious fruit‐boring pests in the world, which caused huge economic losses to the fruit industry including pear and apple. The heavy usage of synthetic insecticides resulted in different degrees of resistance of G. molesta to some commonly used insecticides. However, the tolerance mechanisms of G. molesta to insecticides are still unclear. Glutathione S‐transferases (GSTs) belong to the superfamily of detoxifying enzymes and mainly play important roles in detoxification metabolism and insecticide susceptibility of insects. In this study, we first evaluated the toxicity of three insecticides including emamectin benzoate, chlorantraniliprole and lambda‐cyhalothrin on G. molesta at different developmental stages. Synergism study showed that the susceptibility of G. molesta larvae to these three insecticides obviously increased when the enzyme activity of GST was inhibited by diethyl maleate compared with the controls. Next, we screened out six GmGST genes which are upregulated after insecticides treatment from a total of 21 GmGST genes and analysed their sequence characteristics and expression profiles. RNAi and bioassay results further revealed that the mortality of 5th instar larvae significantly increased after exposure to LC30 of emamectin benzoate, chlorantraniliprole and lambda‐cyhalothrin when silencing of GmGSTo2, GmGSTs1 and GmGSTz1 compared with the controls. In conclusion, this study indicated that GmGSTo2, GmGSTs1 and GmGSTz1 play important roles in insecticides susceptibility of G. molesta to three commonly used insecticides, which is significance for its future integrated management. [ABSTRACT FROM AUTHOR]

[Objectives] To investigate the effects of temperature and humidity on the population dynamics of Grapholita molesta, a pest that causes significant losses to pear crops worldwide. [Methods] A monitoring site was set up in a pear orchard in Daxing, Beijing municipality where sex pheromone traps were used to monitor the population dynamics of adult G. molesta over three years (2018-2021). The data obtained were combined with local meteorological data collected over the same period to analyze the relationship between temperature, humidity and population dynamics. [Results] G. molesta began to appear in the pear orchard in mid to late March. Four population peaks occurred each year; in mid to late April, mid-June, mid to late July and early to mid-September. There was a significant relationship between the average and maximum temperature and population density, which can be described by the equation Y= - 5.62 - 0.16X1+0.72X2+0.52X3+0.18X4, where X3 is the highest temperature, X1 is the average temperature, X2 is the lowest temperature and X4 is the average relative humidity. The relative importance of these factors was: X3> X1> X2> X4. [Conclusion] There is a significant relationship between the occurrence of G. molesta in pear orchards in Daxing, Beijing municipality, and local temperature and humidity data. These results lay a foundation for developing a model to predict the occurrence of G. molesta. [ABSTRACT FROM AUTHOR]

Currently, the predominant method for managing pests in orchards is chemical control. However, prolonged use of chemicals leads to resistance issues and raise ecological safety. A promising approach to tackle these challenges involves nanoparticles-mediated delivery system of dsRNA and pesticides. Despite its potential, this strategy has not been widely applied in controlling pests in pear orchards. In this study, we developed a nanoparticle-mediated ternary biopesticide to tackle resistance and safety concerns associated with calmodulin dsRNA and cyantraniliprole. Initially, we assessed the effectiveness of cyantraniliprole against two key pear pests, Grapholita molesta and Cacopsylla chinensis. Subsequently, we observed an upregualtion of genes CaM and CN following cyantraniliprole treatment. Furthermore, inhibiting or silencing GmCaM and CcGaM enhanced the sensitivity to cyantraniliprole more effectively. By introducing hairpin RNA into the pET30a-BL21 RNaseIII− system to silence GmCaM and CcCaM , we developed a nanoparticle-mediated co-delivery system that exhibited improved control over these two pests. Importantly, our research demonstrated that using reduced cyantraniliprole dosages through ternary biopesticides could help mitigate risks to natural enemies. Overall, our research emphasizes the enhanced effectiveness of ternary biopesticides in boosting the performance of dsRNA and pesticide against pear pests, while fostering environmental sustainability—a novel advancement in this field. [Display omitted] • Cyantraniliprole is a high-efficiency insecticide to control two key pear pests, Grapholita molesta and Cacopsylla chinensis. • Inhibition of GmCaM and CcGaM genes could enhance the sensitivity of G. molesta and C. chinensis to cyantraniliprole. • Successful formulation of nanoparticle-mediated ternary biopesticides for improved control of G. molesta and C. chinensis. • Demonstration of reducing cyantraniliprole dosages through ternary biopesticides to mitigate risks to natural enemies. [ABSTRACT FROM AUTHOR]

Cosmopolitan agricultural herbivorous pests are provided with a wide range of potential hosts. Therefore, they have high carrying capacity, and can cause extremely severe damage in agroecosystems. Understanding the ecological mechanisms of their population dynamics, especially as they relate to large-scale meteorological variations and geographical landscape influences, can help us to reveal how they became such important pests. The oriental fruit moth, Grapholita molesta, is a typical example of a significant pest distributed on a large scale, which is capable of damaging fruit trees of economic value such as peach, apple, pear, etc. This pest not only occurs in China, but exists on all continents except Antarctica. In order to prevent major pests and diseases, a system of plant protection has been established gradually in peach orchards within the Modern Agro-industry Technology Research System in China (CARS) since 2009. In the system, we collected the monitoring data of G. molesta by using pheromone traps at 17 experimental stations, and then used the corresponding climate data (temperature and precipitation) to explore the link between climate factors using mixed models. The results show that both monthly mean temperature and precipitation had a significant positive correlation with the occurrence of G. molesta. Therefore, global warming with higher levels of precipitation may favor G. molesta, allowing it to outperform other potential pests at the population level in peach orchards, on a large scale. [ABSTRACT FROM AUTHOR]

When compared with the unamended control, the developmental times of larvae, pupae, or entire immature stage were shorter on artificial diets amended with 3 or 6 mg/g (low and moderate concentrations) of amygdalin, whereas the developmental time increased on artificial diets amended with 48 mg/g (high concentration) of amygdalin. The unamended artificial diet (0 mg of amygdalin per g of diet) was the control, and then the mass fractions of amygdalin in the treatment artificial diets were 3, 6, 12, 24, and 48 mg of amygdalin per g of initial artificial diet. Larval Feeding on Diets and Developmental Times of Immature Stages B I Proportion of larvae feeding on diets. i b The proportion of larvae feeding on the artificial diets was not significantly affected by amygdalin concentrations ( I F i = 1.339, df = 5,35, I p i = 0.275) (Figure 1). [Extracted from the article]

Simple Summary: The oriental fruit moth Grapholita molesta is an important worldwide fruit tree pest. Its hosts mainly include peach, pear, apple, plum and other Rosaceae fruit trees. In order to explore the mechanism of host adaptation, it is necessary to comprehensively study the effects of feeding and the differences in transcriptional levels of G. molesta. In this study, the growth and development parameters, protease activities, midgut transcriptome analysis and key gene validation of G. molesta fed on five hosts and artificial diet were determined. This study indicated that the significant differences in the growth and development parameters and protease activities, transcriptome of KEGG enrichment and WGCNA analysis of G. molesta fed on different hosts. The transcriptional level of the trypsin gene was consistent with that of qRT-PCR. The trypsin gene played an important role in feeding different hosts of G. molesta. We revealed the adaptive mechanism to different hosts of G. molesta in various aspects and laid a solid foundation for further exploring the molecular mechanism of host adaptation. Grapholita molesta is an important fruit tree worldwide pest which feeds on hosts extensively and does serious harm. In this paper, the growth and development parameters and protease activities of G. molesta fed on different hosts were compared. Using Illumina RNA sequencing technology, 18 midgut samples from five different hosts (apple, pear, plum, peach and peach shoots) and artificial diet were sequenced and compared with the reference genome, resulting in 15269 genes and 2785 predicted new genes. From 15 comparative combinations, DEGs were found from 286 to 4187 in each group, with up-regulated genes from 107 to 2395 and down-regulated genes from 83 to 2665. KEGG pathway analysis showed that DEGs were associated with amino acid metabolism, starch and sucrose metabolism, carbohydrate metabolism, and hydrolase activity. A total of 31 co-expression gene modules of different hosts were identified by WGCNA. qRT-PCR showed that the expression pattern of the trypsin gene was consistent with RNA sequencing. In this study, growth and development parameters, protease activity, DEGs, enrichment analysis and qRT-PCR were combined to reveal the adaptation process to different hosts of G. molesta in many aspects. The results of this study provide a basis for further exploration of the molecular mechanism of host adaptation of G. molesta. [ABSTRACT FROM AUTHOR]

Although neuropeptide corazonin (Crz) has been identified in numerous insect species, the research about its function in regulation of reproduction is still in its infancy. Herein, we characterized the Crz (GmolCrz) and its receptor (GmolCrzR) to investigate their reproductive function in Grapholita molesta. Both molecular docking result and cell-based receptor activity assay showed that GmolCrz could interact with GmolCrzR. Additionally, spatial expression patterns of GmolCrz and GmolCrzR in males were evaluated. Knockdown of GmolCrz or GmolCrzR significantly lengthened copulation duration and decreased fertility in males. In these males, we found that the production of sperm was normal, while the content of accessory gland proteins (Acps) in the accessory gland (AG) was strongly diminished. Furthermore, knockdown of GmolCrz or GmolCrzR in males had no effect on sperm and Acps transfer to females. RNA-seq and gene expression analyses further confirmed that genes involved in serine-type endopeptidase activity were significantly downregulated in the AG upon GmolCrzR knockdown. Finally, sperm activation assays demonstrated that this process was disrupted in the spermatophore of females mated with GmolCrz or GmolCrzR knockdown males, which may cause the decreased fertility in males. Our findings provide new insights into the functions of Crz signaling in a Lepidopteran insect. [Display omitted] • Corazonin (Crz) and its receptor (CrzR) were characterized in Grapholita molesta. • Functionality of CrzR was confirmed by molecular docking and Ca2+ luminescence assay. • Crz signaling is essential for maintaining normal reproduction in G. molesta males. • Dysfunction of Crz signaling impaired the synthetic activity of the accessory gland. • Fertility decline of dsCrz / dsCrzR -treated males was due to impair sperm activation. [ABSTRACT FROM AUTHOR]

Simple Summary: The effect of food supplements on performance of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) moths produced in mass rearing programs is not well known. We investigated the effect of three feeding regimes of the adult moths (supplement with sterile water or 10% honey solution and starvation) on the longevity, 10-d fecundity, flight ability, and the activity of major energy metabolism enzymes in the flight muscles of G. molesta. The results showed that adult food supplement can make a difference to the rearing of G. molesta. Under starvation, the longevity, fecundity, and five flight-related parameters of G. molesta adults were significantly lower than those with access to sterile water and a honey solution. There was no significant difference in adult fecundity and the five flight-related parameters of G. molesta with access to sterile water or honey solution. We concluded that the supply of sterile water is a better food substitution when mass-rearing of G. molesta for some environment-friendly insect pest control tactics such as the sterile insect technique (SIT) The oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is one of the most severe fruit tree pests in China, causing huge economic losses to fruit production. So far, there are few detailed reports on the rearing protocols of G. molesta. In this study, we compared the longevity, 10-d fecundity, flight ability, and the activity of major energy metabolism enzymes in the flight muscles of G. molesta under three feeding regimes (supplement with sterile water, supplement with 10% honey solution and starvation) of the adult moths. The results showed that the longevity, 10-d fecundity, and flight parameters (cumulative flight distance and time, maximum flight distance and duration, and the average flight speed) of adult moths when supplemented with sterile water or honey solution were significantly higher than those of moths that were starved. There were no significant differences in the 10-d fecundity, flight parameters, and the activity of major energy metabolism enzymes of flight muscles between moths that were supplemented with sterile water or 10% honey solution. The flight muscles of G. molesta mainly used carbohydrates as an energy source when sterile water and honey solution were supplemented, and the moth mainly used lipids as an energy source under starvation. Considering the cost and potential for diet contamination during mass-rearing, supplying sterile water is considered a cost effective option for food substitution of adult G. molesta. [ABSTRACT FROM AUTHOR]

Grapholita molesta (Busck) is an important pest in fruit tree production in northern China. In order to determine the resistance level of G. molesta population to commonly used insecticides in Gansu Province, the sensitivity of field populations of G. molesta from three different areas to eight insecticides was determined by the egg dipping method and the status of insecticide resistance was analyzed. The results showed that field populations of G. molesta showed moderate resistance to spinetoram (RR = 10.24-14.27), low to moderate resistance to deltamethyrin (RR = 8.85-11.44), moderate resistance to lambda-cyhalothrin, chlorantraniliprole and spirotetramat (RR = 18.89-86.62), and high resistance to abamectin, emamectin benzoate and indoxacarb (RR = 99.82-189.81). The results provide a scientific basis for the scientific and rational application of insecticides in the control of G. molesta in orchards. [ABSTRACT FROM AUTHOR]

Planting a peach orchard is highly expensive and may be influenced by variables such as attack by pathogens and diseases. Cultivar is one of the most important items within the production system and it is one of the few that may be modified without changes in costs. Current research evaluates the adaptability of peach cultivars 'Chimarrita', 'Eragil', 'Charme', 'Ouro', 'Seleção 01/08', 'FLA 8-1' and 'Della Nona' in the region of Campos Gerais PR Brazil. Experiment was conducted by randomized blocks, with seven treatments (cultivars) and eight replications. Variables analyzed comprised specific leaf area (cm² g-1), stalk diameter (mm), length of main stem (cm), volume of canopy (m³), incidence and severity of rust and early fruit, and percentage of attack by Grapholita molesta (Busck) (%). Cultivars Chimarrita and Ouro were more susceptible to the attack of grapholite (95.5% and 98%, respectively) and rust, with AACPS of 14.65 for Chimarrita and 15.67 for Ouro. Cultivars Charme, Seleção 01/08 and Eragil were more adapted for Campos Gerais, had little effect on growth variables such as the length of main stem, specific leaf area, stalk diameter and volume of canopy, even with the occurrence of diseases and pests which affect the culture. [ABSTRACT FROM AUTHOR]

Glutathione S -transferases (GSTs) are multifunctional enzymes, and insect GSTs play a pivotal role in the metabolism of insecticides. Grapholita molesta is a worldwide pest that causes substantial economic losses to the fruit industry. However, it remains unclear how imidacloprid, a commonly used insecticide in orchards, is metabolized by G. molesta. In the present study, the synergist diethyl maleate (DEM), which inhibits the GST activity, exhibited a 22-fold synergistic ratio against imidacloprid. Two new GST genes, GmGSTD2 (OR096251) and GmGSTD3 (OR096252), were identified and successfully cloned, showing the highest expression in the Malpighian tubes. Knockdown of GmGSTD2 and GmGSTD3 by RNA interference, increased the mortality of G. molesta from 28% to 47% following imidacloprid treatment. Both recombinant GmGSTD2 and GmGSTD3 proteins exhibited 1-chloro-2,4-dinitrobenzene (CDNB) activity and could be inhibited by imidacloprid in vitro , with maximum inhibition was 60% for GmGSTD2 and 80% for GmGSTD3. These results suggested that GSTs participate in the metabolism of imidacloprid with GmGSTD2 and GmGSTD3 playing key roles in this process. [Display omitted] • Glutathione S -transferases play an important role in the metabolism of imidacloprid. • GmGSTD2 and GmGSTD3 are highly expressed in the Malpighian tubes. • Knockdown of GmGSTD2 and GmGSTD3 increases the susceptibility of the Grapholita molesta to imidacloprid. • The activity of GmGSTD2 and GmGSTD3 proteins was inhibited by imidacloprid in vitro. [ABSTRACT FROM AUTHOR]

Some insects that particularly prefer sunny or shaded sites use light intensity to locate suitable oviposition sites during the day. However, it is not known whether crepuscular species can be guided by light for oviposition under dim or variable light conditions. We used the crepuscular moth Grapholita molesta (Busck) (Lepidoptera: Tortricidae), a major pest of stone and pome fruits worldwide, to investigate oviposition response to light at various intensities (1000, 100, 10, and 1 mW m−2). Light intensity in sunny sites in a peach tree canopy is about 10× higher than in shaded sites. In both light vs. dark and brighter light vs. darker light choices, G. molesta females can discriminate differences in light intensity, exhibiting a strong preference for brighter light, independent of light intensity. Moreover, the light‐dependent oviposition responses did not change when exposed to odor stimuli. Our findings show that this crepuscular moth G. molesta can use light intensity to direct oviposition toward relatively sunny sites under dim light conditions. This study highlights the importance of vision for crepuscular species in oviposition site selection. [ABSTRACT FROM AUTHOR]

Grapholita molesta, a worldwide fruit-boring pest, is difficult to be effectively controlled due to the larvae feeding habit inside fruits. Neuropeptide F (NPF) is the crucial molecule modulating feeding behavior of insects. Herein, two genes, NPF1 and NPF2, were identified and cloned from G. molesta. GmolNPF1 had a higher expression in newly hatched larvae than in other developmental stages and mainly in the midgut (major expressive organ). Coincidentally, the stage of newly hatched larvae was the best control period to prevent larvae from entering the fruits. Further study demonstrated that only GmolNPF1 expression increased significantly after starvation and declined after refeeding. After GmolNPF1 knockdown by RNA interference (RNAi), the feeding amount, weight, body size and drill holes rate of larvae decreased significantly, and the number of larvae that ate food within 5 min declined significantly. The pET30-NPF1-BL21(DE3) RNase III system was successful constructed and produced large batch dsRNA (double stranded, ds) of GmolNPF1. The nanocarrier-mediated transdermal dsRNA delivery system enhanced the RNAi efficiency of dsNPF1, significantly decreased the fruit damage and increased the mortality of newly hatched larvae via spraying method. Our research not only revealed the regulation function of GmolNPF1 involved in the feeding behavior of G. molesta, but also showed the NPF1 as a molecular target combined the transdermal dsRNA delivery system will a potential control strategy for pest management in the field. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Odorant-binding proteins (OBPs) are widely and abundantly distributed in the insect sensillar lymph and are essential for insect olfactory processes. The OBPs can capture and transfer odor molecules across the sensillum lymph to odorant receptors and trigger the signal transduction pathway. In this study, a putative OBP gene, GmolOBP 7, was cloned using specific-primers, based on the annotated unigene which forms the antennal transcriptome of Grapholita molesta. Real-time PCR (qRT-PCR) analysis revealed that GmolOBP 7 was highly expressed in the wings of males and the antennae of both male and female adult moths, while low levels were expressed in other tissues. The recombinant GmolOBP7 (rGmolOBP7) was successfully expressed and purified via Ni-ion affinity chromatography. The results of binding assays revealed that rGmolOBP7 exhibited a high binding affinity to the minor sex pheromone 1-dodecanol containing K i of 7.48 μM and had high binding capacities to the host-plant volatiles, such as pear ester, lauraldehyde and α-ocimene. RNA-interference experiments were performed to further assess the function of GmolOBP7. qRT-PCR showed that the levels of mRNA transcripts significantly declined in 1 and 2 day old male and female moths, treated with GmolOBP 7 dsRNA, compared with non-injection controls. The EAG responses of dsRNA-injected males and females to pear ester, as well as the EAG responses of dsRNA-injected males to 1-dodecanol, were significantly reduced compared to the GFP-dsRNA-injected and non-injected controls. We therefore infer that GmolOBP7 has a dual function in the perception and recognition of the host-plant volatiles and sex pheromones. [ABSTRACT FROM AUTHOR]

Abstract: Male and female moth catches of Grapholita molesta (Busck) in traps were evaluated in stone and pome fruit orchards untreated or treated with sex pheromones for mating disruption in Uruguay, Argentina, Chile, USA, and Italy from 2015 to 2017. Trials evaluated various blends loaded into either membrane cup lures or septa. Membrane lures were loaded with terpinyl acetate (TA), acetic acid (AA) and (Z)‐3‐hexenyl acetate alone or in combinations. Two septa lures were loaded with either the three‐component sex pheromone blend for G. molesta alone or in combination with codlemone (2‐PH), the sex pheromone of Cydia pomonella (L). A third septum lure included the combination sex pheromone blend plus pear ester, (E,Z)‐2,4‐ethyl decadienoate (2‐PH/PE), and a fourth septum was loaded with only β‐ocimene. Results were consistent across geographical areas showing that the addition of β‐ocimene or (Z)‐3‐hexenyl acetate did not increase moth catches. The addition of pear ester to the sex pheromone lure marginally increased moth catches. The use of TA and AA together significantly increased moth catches compared with the use of only one of the two components. Traps with the TA/AA lure outperformed the Ajar trap baited with a liquid TA plus sugar bait. The emission rate of AA was not a significant factor affecting the performance of the TA/AA lure. The addition of TA/AA significantly increased moth catches when combined with the 2‐PH lure. The TA/AA lure also allowed traps to catch both sexes. Catch of C. pomonella with the 2‐PH lure was comparable to the use of codlemone; however, moth catch was significantly reduced with the 2‐PH/PE lure. Optimization of these complex lures can likely further improve managers’ ability to monitor G. molesta and help to develop multispecies tortricid lures for use in individual traps. [ABSTRACT FROM AUTHOR]

The oriental fruit moth (OFM) Grapholita molesta (Lepidoptera: Tortricidae) is an important economic pest of stone and pome fruits worldwide. We sequenced the OFM genome using next-generation sequencing and characterized the microsatellite distribution. In total, 56,674 microsatellites were identified, with 11,584 loci suitable for primer design. Twenty-seven polymorphic microsatellites, including 24 loci with trinucleotide repeat and three with pentanucleotide repeat, were validated in 95 individuals from four natural populations. The allele numbers ranged from 4 to 40, with an average value of 13.7 per locus. A high frequency of null alleles was observed in most loci developed for the OFM. Three marker panels, all of the loci, nine loci with the lowest null allele frequencies, and nine loci with the highest null allele frequencies, were established for population genetics analyses. The null allele influenced estimations of genetic diversity parameters but not the OFM's genetic structure. Both a STRUCTURE analysis and a discriminant analysis of principal components, using the three marker panels, divided the four natural populations into three groups. However, more individuals were incorrectly assigned by the STRUCTURE analysis when the marker panel with the highest null allele frequency was used compared with the other two panels. Our study provides empirical research on the effects of null alleles on population genetics analyses. The microsatellites developed will be valuable markers for genetic studies of the OFM. [ABSTRACT FROM AUTHOR]

The oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), is an important pest of most stone and pome fruits and causes serious damage to the fruit industry worldwide. This insect pest has been primarily controlled through the application of insecticides; as a result, G. molesta has developed resistance to many different types of insecticides. To identify detoxification genes, we have, de novo, sequenced the transcriptome of G. molesta (Lepidoptera: Tortricidae) and yielded 58,970 unigenes of which 26,985 unigenes matched to known proteins. In total, 2,040 simple sequence repeats have been identified. The comprehensive transcriptome data set has permitted us to identify members of important gene families related to detoxification in G. molesta, including 77 unigenes of putative cytochrome P450s, 28 of glutathione S-transferases, 46 of Carboxylesterases, and 31 of insecticide targets. Orthologs of some of these unigenes have shown to play a pivotal role in insecticide resistance in other insect species and those unigenes likely have similar functions in G. molesta. [ABSTRACT FROM AUTHOR]

In this study, odorant binding proteins (OBPs) and chemosensory protein (CSP), which are associated with the sensitivity of Grapholita molesta , were comprehensively analysed using bioinformatics. The full-length cDNAs of GmolOBP1, GmolOBP2, and GmolCSP were downloaded and their open reading frames (ORFs) were analysed. Their physicochemical properties were determined and their structures and functions were predicted. Additionally, a phylogenetic tree was constructed to investigate the evolutionary relationships among GmolOBP1, GmolOBP2, GmolCSP, and 14 other insect proteins. GmolOBP1, GmolOBP2 and GmolCSP were composed of 164, 161, and 127 amino acids. GmolOBP1 and GmolOBP2 contained 7 and 6 cysteine residues forming 3 disulphide bonds. The transmembrane, hydrophobic, and signal peptide regions overlapped in GmolOBP1 and GmolCSP and were located in the extracellular environment. GmolCSP showed more coiled coils and a smaller cavity in the three-dimensional structure than GmolOBP1 and GmolOBP2. In the phylogenetic tree, GmolOBP1, GmolOBP2, and GmolCSP were in different clusters or sub-clusters. In conclusion, GmolOBP1 and GmolOBP2 shared some common properties with other OBPs. Additionally, GmolOBP1, GmolOBP2, and GmolCSP may have evolved independently. [ABSTRACT FROM AUTHOR]

To seek sufficient resources for growth, survival and reproduction, most insect species must tackle host selection problems. The development, survivorship and fecundity of the oriental fruit moth Grapholita molesta (Busck) on apricot Prunus armeniaca L., plum Prunus salicina L., nectarine Prunus persica var. nectarina L. Batsch, peach Prunus persica L., pear Pyrus sorotina Will. and apple Malus domestica Mill. were determined to test host suitability in the laboratory. Larval development rate was faster, and survival rate was higher on plum and nectarine compared with the other fruits. Adult longevity and the duration of oviposition were significantly longer on nectarine. Adult fecundity varied significantly among the tested host plants, with the highest fecundity being observed on apple (135.63 eggs/female), followed by pear (104.90 eggs/female). The intrinsic rate of increase ( rm) was greater on pear and apple (0.1574 and 0.1221 eggs per female per day, respectively). Different abilities to develop and reproduce on various host plants partly explain the seasonal host selection of G. molesta. [ABSTRACT FROM AUTHOR]

The Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of tree fruits worldwide, and the diapausing larvae overwinter in cryptic habitats. Investigations of overwintering G. molesta were conducted in adjacent peach, pear and apple orchards in Northern China over three consecutive winters to determine the overwintering site and habitat preferences of the moth. Counts of overwintering larvae in the different orchards demonstrated that the late-maturing peach orchard (‘Shenzhou honey peach’) was the most preferred overwintering habitat with more than 90% of the collected larvae. Larvae were more abundant in host trees, and they very rarely overwintered in the soil. The overwintering site preferences on the host trees were significantly different; over 50% larvae were located in the tree trunks, and followed by main branches. Most of the G. molesta overwintered on the sunny side of the host trees at or below 60 cm from the ground; a few were cocooned on the shaded sides of the trees or greater than 60 cm from the ground. G. molesta began overwintering between August and October, mid- to late September was the peak period for entering winter diapause during 2011–2013 (77.78, 67.59 and 71.15%, respectively). Our findings improve understanding of the orchard habitat and overwintering site preferences of G. molesta and would be useful in the development of efficient forecasting and pest-management strategies for orchards during the winter and early spring. [ABSTRACT FROM PUBLISHER]

Cydia pomonella (L.) and Cydia molesta (Busck) (Lepidoptera: Tortricidae) are two important lepidopteran pests that may co-occur in apple orchards and are difficult to differentiate in the larval stage. We investigate the possibility of using near-infrared spectroscopy (NIRS) coupled with partial least squares analysis to distinguish the larvae of the two species. We further assess whether wild individuals can be differentiated using laboratory strains of the two species for model calibration. The NIRS spectra of C. molesta and C. pomonella differed most in the wavelengths between 1,142 and 1,338 nm. Using these wavelengths, partial least squares analysis allowed the differentiation of C. molesta and C. pomonella at the larval stage with very low error, but only as long as both the calibration and prediction sets for individuals had the same origin (either both from the laboratory or both from the field). Errors that appeared when using laboratory individuals for calibration were owing to the divergence of the C. pomonella laboratory strain, most likely following evolution during rearing. Thus, NIRS appears to be a promising tool for the easy and rapid identification of individuals in the field, provided that it is calibrated based on a subset of field individuals. [ABSTRACT FROM PUBLISHER]

The response profile of olfactory receptor neurons (ORNs) of male Grapholita molesta (Busck) to the three female sex pheromone components [( Z )-8-dodecenyl acetate ( Z 8-12:Ac), ( E )-8-dodecenyl acetate ( E 8-12:Ac), and (Z)-8-dodecenyl alcohol ( Z 8-12:OH)] was tested with single sensillum electrophysiology. Sensilla trichodea housed normally one, but sometimes two or three ORNs with distinct action potential amplitudes. One third of the sensilla contacted contained ORNs that were unresponsive to any of the pheromone components tested. The remaining sensilla contained one ORN that responded either to the major pheromone component, Z 8-12:Ac (“Z-cells”, 63.7% of sensilla), or to its isomer E 8-12:Ac (“E-cells”, 7.4% of sensilla). 31% of Z- and E-sensilla had 1 or 2 additional cells, but these did not respond to pheromone. None of the 176 sensilla contacted hosted ORNs that responded to Z 8-12:OH. The proportion of Z- and E-cells on the antennae (100:11.6, respectively) is similar to the proportion of these compounds in the blend (100:6, respectively). The response of Z-cells was very specific, whereas E-cells also responded to the Z isomer, albeit with lower sensitivity. [ABSTRACT FROM AUTHOR]

The Oriental Fruit Moth Grapholita molesta (Busck) causes substantial damage to stone and pome fruit crops worldwide. Light-based traps offer a potential means for pest monitoring and management. In this study, we tested the preference of G. molesta for the following light sources: monochromatic light produced from light-emitting diodes (LEDs) (red, orange, yellow, green, blue, violet, and white), specific wavelengths of light produced from filters (405, 450, 480, 512, 540, 576, and 610 nm), and polychromatic light produced by different numbers (0, 12, 24, and 36) of green, blue, and violet LEDs. The arrangement of polychromatic lights was based on an orthogonal design matrix of L16 (43). Based on the results of former studies, we further determined the optimal number of green and violet LEDs. The results showed that: 1) G. molesta strongly preferred the green, violet, and blue LEDs; 2) G. molesta significantly preferred light at 405 nm, followed by 540 nm, and showed no phototaxis to 480 nm; 3) for the polychromatic light configuration, violet and green were the factors that determined the preference of G. molesta, and the lamp with 12 violet LEDs captured the most moths; and 4) for the lamps with different light intensities, 36 violet LEDs or 12 green LEDs attracted the most moths, with the former performing better. [ABSTRACT FROM AUTHOR]

Grapholita molesta (Busck) is a worldwide insect pest damaging stone and pome fruits. High temperature can significantly affect insect survival, development and fecundity. Heat shock protein (Hsp) genes were speculated to possess a pivotal function in response to high temperature stress. In this study, two full-length Hsp genes, Gmhsp90 and Gmhsp70, were cloned from G. molesta using rapid amplification of complementary DNA ends (RACE). The open reading frames of Gmhsp90 and Gmhsp70 obtained were 2 148 bp and 1 998 bp in length, respectively. Their deduced amino acids showed high homology to Hsp genes of other species. Subsequently, the transcriptional expression of Gmhsp90 and Gmhsp70 in G. molesta adults exposed at various temperatures (26, 29, 32, 35, 38, 41 and 44°C) for 1 h and at 41°C for various time duration (0, 15, 30, 45, 60, 75, 90 and 105 min) were investigated via real time quantitative polymerase chain reaction (qPCR). The relative expression levels of Gmhsp90 and Gmhsp70 in G. molesta adults were both up-regulated with the rise of temperature and time duration. In addition, the Gmhsp70 usually showed a higher transcription accumulation than Gmhsp90. Interestingly, Gmhsp90 and Gmhsp70 in female adults could be induced much earlier than that in males, and the effective induction temperature in females was also lower than that in males. The distinct expression profiles of Gmhsp90 and Gmhsp70 indicated that Gmhsp90 and Gmhsp70 may play important roles in G. molesta adults responding to a thermal threat, and there is difference on induction between sexes. [ABSTRACT FROM AUTHOR]

Copyright of Revista Agro@mbiente On-line is the property of Revista Agro@mbiente On-line and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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. [ABSTRACT FROM AUTHOR]

• Cuticular bacterial diversity of Grapholita molesta was investigated by 16S rDNA sequencing. • The dominant bacteria on the cuticle of Grapholita molesta were cultured and identified. • Cuticular bacterium Pantoea sp. exhibited high antifungal activity against Beauveria bassiana. The oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a destructive orchard pest native to the Asian subcontinent that has spread throughout many fruit-growing regions of the world. The entomopathogenic fungus Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Hypocreales: Cordycipitaceae) is widely employed for control of insect pests, including G. molesta. Various studies have shown that microorganisms present on the insect cuticle can inhibit fungal spore germination and growth, thus inhibiting their pathogenicity and biological control efficacy. We conducted bioassays on larvae pre-treated with antibiotics to test whether cuticular microbiota could reduce the pathogenicity of B. bassiana to G. molesta. Control larvae (untreated with antibiotics) had higher survival than antibiotic-treated larvae following inoculation with B. bassiana , indicating that cuticular microbiota inhibited infection of G. molesta by B. bassiana. The bacterial diversity present on the cuticle of G. molesta larvae was characterized by 16S rDNA amplicon sequencing. The dominant bacterium isolated was Pantoea sp. and its antagonism toward B. bassiana was assayed in vitro using the inhibition zone method. Inhibitory effects on the pathogenicity of Pantoea sp. against B. bassiana were demonstrated by reintroducing the bacterium to G. molesta larvae that had been pre-treated with antibiotic, which increased their survival in comparison to antibiotic-treated larvae following inoculation with B. bassiana. This study provides potentially valuable insights for maximizing the efficacy of B. bassiana applications for biological control of G. molesta. [ABSTRACT FROM AUTHOR]

Nongenetic parental effects may affect offspring phenotype, and in species with multiple generations per year, these effects may cause life-history traits to vary over the season. We investigated the effects of parental, offspring developmental and offspring adult temperatures on a suite of life-history traits in the globally invasive agricultural pest Grapholita molesta. A low parental temperature resulted in female offspring that developed faster at low developmental temperature compared with females whose parents were reared at high temperature. Furthermore, females whose parents were reared at low temperature were heavier and more fecund and had better flight abilities than females whose parents were reared at high temperature. In addition to these cross-generational effects, females developed at low temperature had similar flight abilities at low and high ambient temperatures, whereas females developed at high temperature had poorer flight abilities at low than at high ambient temperature. Our findings demonstrate a pronounced benefit of low parental temperature on offspring performance, as well as between- and within-generation effects of acclimation to low temperature. In cooler environments, the offspring generation is expected to develop more rapidly than the parental generation and to comprise more fecund and more dispersive females. By producing phenotypes that are adaptive to the conditions inducing them as well as heritable, cross-generational plasticity can influence the evolutionary trajectory of populations. The potential for short-term acclimation to low temperature may allow expanding insect populations to better cope with novel environments and may help to explain the spread and establishment of invasive species. [ABSTRACT FROM AUTHOR]

Studies in Oregon, California, Pennsylvania and Italy evaluated the relative performance of the Ajar trap compared with several other traps for the capture of Grapholita molesta (Busck), in pome and stone fruit orchards treated with sex pheromone dispensers for mating disruption. The Ajar is a delta-shaped trap with a screened jar filled with an aqueous terpinyl acetate plus brown sugar bait solution ( TAS) that opens inside the trap and is surrounded by a sticky liner. The TAS-baited Ajar trap was evaluated with and without the addition of a sex pheromone lure and compared with a delta trap baited with a sex pheromone lure and a bucket trap filled with the TAS bait. Although the Ajar trap had a 90% lower evaporation of the TAS bait than the bucket trap, both of them caught similar numbers in the majority of the field tests of both sexes of G. molesta. The addition of the sex pheromone lure did not increase moth catches by the TAS-baited Ajar trap. The TAS-baited Ajar trap caught significantly greater numbers of moths than the sex pheromone-baited delta trap in 18 of the 20 orchards. Few hymenopterans were caught in orange TAS-baited Ajar traps, but the catch of flies and other moths relative to the target pest remained high. Flight tunnel and field tests evaluated the effect of several screen designs on the catches of G. molesta and non-target species. All exclusion devices significantly reduced the catch of larger moths. However, designs that did not reduce the catch of male G. molesta did not reduce the catch of muscid flies. Exclusion devices with openings <7.0 mm significantly reduced the catch of female G. molesta. The addition of ( E)- β-farnesene, ( E)- β-ocimene or butyl hexanoate septa lures to TAS-baited Ajar traps significantly increased total moth catch. The addition of ( E)- β-ocimene also significantly increased female moth catch. [ABSTRACT FROM AUTHOR]

Abstract: Three tortricid pests, Grapholita dimorpha (Komai), G. molesta (Busck), and Carposina sasakii (Matsumura), are known as internal apple feeders in Korea. To identify young larvae, this study developed two types of molecular markers from their mitochondrial DNA (mtDNA) sequences. To this end, six different loci of mtDNA were sequenced in G. dimorpha: cytochrome oxidase subunit I (460bp), cytochrome oxidase subunit II (446bp), cytochrome b (308bp), NADH dehydrogenase 3 (585bp), NADH dehydrogenase 4 (ND4, 835bp), and 16S rRNA (1300bp). These sequences were compared with those of G. molesta and C. sasakii in order to develop PCR–RFLP and diagnostic primers. ND4 locus was selected to be used for developing a PCR–RFLP marker. ND4-Swa I digests showed two bands for G. dimorpha, one band for G. molesta, and three bands for C. sasakii. On the other hand, species-specific diagnostic PCR primers were developed using ND4 locus. These markers were then applied to diagnose larvae infesting apples to determine species-specific fruit damage patterns, in which G. dimorpha, G. molesta, and C. sasakii showed different feeding behaviors in terms of their main feeding sites in apple fruits. [Copyright &y& Elsevier]

Sensory adaptation has been measured ill the antennae of male Grapholita molesta (Busek) after 15 min of exposure to its main pheromone compound (Z)-8-dodecen-l-yl acetate (Z8-12:OAc) at the aerial concentration of 1 ng/m³ measured in orchards treated with pheromone for mating disruption. Exposing males to this aerial concentration of Z8-12:OAc for 15 rain, however, had only a small effect on their ability to orientate by flight to virgin calling females in a flight tunnel. Experiments were undertaken to determine if exposure to the main pheromoue compound in combination with the two biologically active minor compounds of this species, (E)-8-dodeeeu-l-yl acetate (E8-12:OAc) and (Z)-8-dodecen-l-ol (Z8-12:OH) would induce greater levels of sensory adaptation and have a greater effect on male sexual behavior. The exposure of male antennae to 0.5 g/m³ air of one of the three pheromone compounds induced sensory adaptation to this compound and to the other two pheromone compounds demonstrating cross adaptation. Average percentage sensory adaptation to a pheromone compound was similar after 15 min of exposure to 1 ng/m³ air of Z8-12:OAc or to 1 ng/m ³ air of a 1:hl or 93:6:1 blend of Z8-12:OAc, E8-12:OAc, and Z8-12:OH. The exposure of males to 1 ng/m³ air of Z8-12:OAc or the two ratios of Z8-12:OAc, E8-12:OAc, and Z8-12:OH for 15 rain had no effect on their ability to orientate to a virgin calling female. The implications of these results for the operative mechanisms of sex pheromone-mediated mating disruption of this species are discussed. [ABSTRACT FROM AUTHOR]

The monoterpenoid citral synergized the electroantennogram (EAG) response of male Grapholita molesta (Busck) antennae to its main pheromone compound Z8-12:OAc. The response to a 10-µg pheromone stimulus increased by 32, 45, 54, 71 and 94% with the addition of 0.1, 1, 10, 100 and 1,000/µg of citral, respectively. There was no detectable response to 0.1, 1, or 10 µg of citral; the response to 100 and 1,000/µg of citral was 31 and 79% of the response to 10/µg of Z8-12:OAc. In a flight tunnel, citral affected the mate-seeking behavior of males. There was a 66% reduction in the number of males orientating by flight to a virgin calling female when citral was emitted at 1,000 ng/min ≈1 cm downwind from a female. Pheromone and citral induced sensory adaptation in male antennae, but citral did not synergize the effect of pheromone. The exposure of antennae to 1 ng Z8-12:OAc/m³ air, 1 ng citral/m³ air, 1 ng Z8-12:OAc + 1 ng citral/m³ air, or to 1 ng Z8-12:OAc + 100 ng citral/m³ air for 15 min resulted in a similar reduction in EAG response of 47-63%. The exposure of males to these same treatments for 15 min had no effect on their ability to orientate to a virgin calling female in a flight tunnel. The potential for using citral to control G. molesta by mating disruption is discussed. [ABSTRACT FROM AUTHOR]

Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of tree fruits worldwide, overwinters in mature larva diapause. However, little is known about the physiological explanation for diapause development in this pest. In this study, we analyzed the dynamic metabolic processes of carbohydrate, protein and antioxidant enzymes in diapausing larvae, which were maintained at low temperatures of 4 and 10°C under laboratory conditions, and 24°C as control for up to 4 months. After 100 days of maintenance, diapause could be terminated at low temperatures, as indicated by the pupation rate, the larvae were more conducive to complete diapause development at 10°C compared to 4°C. During diapause, total sugar and glycogen content decreased and trehalose content increased at low temperatures; glycerol content significantly increased at 4°C, but not at 10°C; protein content did not significantly changed at low temperature, but slightly decreased during the middle phase of diapause. Additionally, the activities of SOD and CAT increased and POD activities decreased during the middle phase of diapause at low temperatures. Our results indicate that temperature and diapause intensity significantly affected the carbohydrate content and antioxidant enzymes activities of the diapausing larvae, low temperature plays a predominant role in diapause termination, and antioxidant enzymes have a similar role in the regulation of energy metabolism as carbohydrate. [ABSTRACT FROM AUTHOR]

Abstract: The oriental fruit moth, Grapholita molesta, is becoming a large threat to Korean pear production. Timely management of the egg and early larval stages from the spring emergence is critical to reduce the G. molesta population during the pear growing season. A model was developed to precisely predict the spring occurrence of G. molesta adults as a function of accumulated degree-days. The model was validated with male moth caught in sex pheromone-baited traps placed in pear orchards at two major pear production regions (Icheon and Naju) of Korea in 2010. We applied nine distribution models to describe the cumulative proportions of G. molesta males caught relative to accumulated degree-days. The observed phenology of the G. molesta spring population was well described by the nine models. The predicted dates for the cumulative 50% male moth catches were within a 5day period. Based on statistical information criteria (Akaike''s and Bayes–Schwartz information criteria), we recommend the sigmoid function referred by Brown and Mayer, because of its ease of use and meaningfulness; the parameter “b” denotes the degree-day accumulation at 50% moth emergence. The G. molesta spring emergence model could be applied to determine optimal chemical treatment timing for controlling G. molesta in fruit tree orchards and further help to develop a full-cycle phenology model of G. molesta. [Copyright &y& Elsevier]

Sexual behavior of male moths after prolonged exposure to the 1-ng pheromone/m³ air previously measured in orchards treated with pheromone for mating disruption was examined in a flight tunnel. The exposure of Graptwlita molesta (Busck) to 1-ng (Z)-8-dodecen-1-yl acetate (Z8- 12:OAc)/m³ air for 15 min had no effect on their ability to fly upwind to a conspecific, virgin calling female. After 30 min of exposure, males exposed to a control treatment were 1.4x more likely orient to a female than males exposed to pheromone-treated air. Some G. molesta males retained the ability to orient to a female after a 3O-min exposure period when the aerial concentration of Z8-12:OAc was increased 500,00OK to 0.5 gm/m3. Prolonged exposure to Z8-12:OAc did not affect response to a synthetic pheromone lure. The time required to initiate behavioral responses to a female or a lure was not affected by pheromone exposure. Male Choristoneura rosaceana (Harris) exposed to a control treatment for 15 min were 38.5x more likely to orient to a conspecific, virgin calling female than males exposed to 1-ng (Z)-11-tetradecen-1-yl acetate (Z11-14:OAc)/m³ air for 15 min. After 30 min of exposure males were unable to fly upwind to a female. Males exposed to a control treatment for 15 min were 4.3x more likely to fly upwind to a synthetic pheromone lure than males exposed to 1-ng Z11-14:OAc/m³ air for 15 min. The time required to initiate behavioral responses to a female or a lure was not affected by exposure to pheromone. [ABSTRACT FROM AUTHOR]

Fruit orchards in New Jersey are usually isolated from neighboring farms and diversified, often containing separate plantings of peach (Prunus spp.) and apple (Mains spp.). These crops can suffer significant damage from oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae). This study evaluated the effect of managing G. molesta by using sex pheromone- based mating disruption applied to both peaches and apples (whole-farm mating disruption) rather than treating either crop alone. In year 1 of the experiment, G. molesta mating disruption applied to the adjacent peach and apple blocks provided better control than treating peaches or apples alone. During year 2, treating these adjacent blocks or only treating apples controlled G. molesta equally well. G. molesta populations were so low at the end of year 2 that mating disruption was not applied against this pest during year 3. This allowed us to determine whether applying mating disruption for two consecutive years controlled G. molesta well enough that it eliminated the need mating disruption for three consecutive years. The mean cumulative number of G. molesta captured in plots where both peaches and apples had been treated did not exceed two moths per trap in the third year of this experiment. In contrast, G. molesta capture rebounded during August in peaches and apples that had not been treated with mating disruption the previous 2 yr. Implications for managing G. molesta by using mating disruption as a "whole-farm" tactic as well applying it for two consecutive years and not a third year are discussed. [ABSTRACT FROM AUTHOR]

Two novel general odorant-binding protein (GOBP) cDNAs ( GmolGOBP1 and GmolGOBP2) were cloned and characterized from female antennal tissue of the oriental fruit moth, Grapholita molesta. We focused our investigation on this olfactory protein family by using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends-PCR (RACE-PCR). The full-length open reading frames of GmolGOBP1 and GmolGOBP2 were 492 and 483 nucleotides long, which encode 164 and 161 amino acid residue peptides, respectively. Protein signature analyses revealed that they each contained six conserved cysteines with an N-terminal signal sequence of 20 amino acids. The alignment of the two deduced protein sequences with other Lepidoptera GOBPs showed high sequence similarity (70-80 %) with other full-length sequences from GenBank. Sequence similarity between the two GOBPs was only 48 %, suggesting that the two proteins belong to different classes of lepidopteran GOBPs. RT-PCR analysis revealed that the two GOBP genes were expressed only in antennae of both sexes. Real-time PCR analysis further indicated that the transcript level of GmolGOBP1 was higher in males than in females, whereas the transcript level of GmolGOBP2 was higher in females than in males. Temporally, the two GOBP genes were expressed during the complete photoperiod (15L:9D). The highest transcript levels of GmolGOBP1 in both sexes and GmolGOBP2 in females were detected at the end of photophase and during scotophase. The expression of GmolGOBP2 in males remained at similar levels during the complete photoperiod. Based on these results, the possible physiological functions of GmolGOBPs are discussed. [ABSTRACT FROM AUTHOR]

Abstract: A fusion of information technology (IT) and sex pheromone monitoring provides a remote sensing IT-pheromone trap to monitor Oriental fruit moth, Grapholita molesta, populations in apple orchards. Once a male of G. molesta is attracted to its sex pheromone lure in the trap, an infrared sensor installed at the funnel-shaped orifice generates an electric signal. The signal is processed in a central processor and then transferred to an internet site via a code division multiple access protocol. The signal also contains information about when each male is caught. Daily trapping information from different localities is archived in a website. The accuracy of IT-pheromone traps in detecting male catches was shown by a high correlation (r =0.956) between the generated IT signals and actual numbers of males caught in the trap in apple orchards. Using this IT-pheromone trap, G. molesta in apple orchards was monitored for one year. These data were compared with monitoring data obtained from a conventional wing type-based sticky trap containing the identical sex pheromone lure. Both showed four characteristic adult peaks from April to September and were significantly correlated (r =0.695). IT-pheromone traps also gave real-time signals of male catches in the field. These real-time signals of male catches showed a characteristic diel attraction rhythm from 4pm to midnight. The diel rhythm of the male response to the sex pheromone started earlier in the evening in the spring season compared to mid and late seasons. This study provides a novel sex pheromone trap for G. molesta to monitor its population in field conditions in real-time without visiting or counting. The field monitoring data can be accessed any time through a designated internet website. [Copyright &y& Elsevier]