-To assess cold tolerance as a factor for potential distribution of Monochamus alternatus, parameters of cold hardiness and acclimation responses of the beetle were examined. Supercooling points (SCPs) of eggs, larvae, pupae, and adults were significantly different, the eggs having the lowest value (-19.8 • C) and the adults the highest (-6.6 • C). No significant differences were observed between the SCPs of pupae and overwintering 5th instar larvae, but mean SCPs significantly declined with the development of larval instars. Mortality of overwintering larvae increased as temperature declined and exposure to low temperatures was prolonged. No individual survived at -25 • C. Lethal times of Lt 50 and Lt 95 were 35.8 d and 65.4 d at -10 • C, respectively. Acclimation significantly improved cold tolerance of autumn 4-5th instar larvae, but not of overwintering larvae. Based on these results, the -10 • C January mean air temperature isotherm is suggested as the northern limit of the beetle potential distribution in China.Monochamus alternatus / cold tolerance / acclimation / distribution limit / isotherm Résumé -La résistance au froid comme facteur pour évaluer la distribution potentielle du scieur de pin japonais Monochamus alternatus (Coleoptera : Cerambycidae) en Chine. Afin d'estimer la résistance au froid et les capacités de dispersion de Monochamus alternatus, nous avons étudié les réponses de ce coléoptère à la rigueur hivernale, avec ou sans acclimatation. La valeur moyenne du point de super-congélation (SCP) est sensiblement différente entre les oeufs, les larves, les chrysalides, et les adultes, les oeufs présentant la valeur la plus basse (-19.8 • C) et les adultes la plus élevée (-6.6 • C). Bien que cette valeur moyenne de SCP ait progressivement diminué au fur et à mesure du développement larvaire, aucune différence significative n'a été observée entre les larves hivernantes de 5 e stade et les chrysalides. La mortalité des larves hivernantes augmente avec la diminution de la température et avec la durée d'exposition aux basses températures. Aucun oeuf, larve, chrysalide ou adulte ont survécu à une exposition à -25 • C. Pour une température de -10 • C, la durée létale d'exposition a été établie à 35.8 d (Lt 50 ) et 65.4 d (Lt 95 ). L'acclimatation préalable a augmenté de manière significative la tolérance au froid des larves de 4 e et 5 e stades présentes en automne, mais pas celle des larves hivernantes. L'isotherme -10 • C pour la température moyenne de l'air en janvier a été proposé comme limite septentrionale de la distribution de coléoptère en Chine.Monochamus alternatus / tolérance au froid acclimatation / limite de distribution / isotherme

BACKGROUNDGrapholita molesta (Busck) is a fruit pest worldwide. While sex pheromones‐based technology for male attraction has made great progress in the monitoring or mass trapping of G. molesta, the attraction of males alone is not an effective reproductive control strategy. The integration of sex pheromones with female attractants, which have been reported to attract adult females and males, is therefore necessary. To determine a suitable dual‐sex attractant for trapping G. molesta, combinations of four attractants [sex pheromones (ph), host‐plant volatiles (pp), sugar‐acetic acid‐ethanol‐water solutions (ss), and food lures (fl)] were screened using electroantennograms, wind tunnel experiments, and field trial tests. Various mediums and antioxidants were then added to the selected attractants combination (AC) and examined in the field.RESULTSThe responses of G. molesta to attractants differed significantly between the sexes. Increases in male activation behavior and trapping were motivated by ph, while pp and particularly ss increased adult antennae perception. In response to fl alone or together with ph, more male or female individuals were trapped. This indicates that ph, as a sex lure, and fl, as a host lure, may complete male and female attraction. Consequently, this combination is suggested. In the field trials, the additions of 10 μL of honey and 35% (184.3 μg) of 2,6‐di‐tert‐butyl‐4‐methylphenol [BTH] (preservatives) to the AC (ph + fl) resulted in moth captures equal to that of a commercial sex pheromones lure.CONCLUSIONA dual‐sex attractant composed of ph, fl, honey, and BTH is recommended for trapping G. molesta in the field. © 2020 Society of Chemical Industry

Changes in contact angles and SFE correlated with the change of the leaf surface wettability. Leaves became easier to wet (higher SFE), with an overall increasing polar component to the surface, with increasing age after flowering. As expected, changes in wettability were found in pear leaves at different stages after flowering and in different regions (P < 0.05). Pear leaves from Yuanping were easier to wet than leaves from Yuci and Linyi, and adaxial surfaces were easier to wet than abaxial surfaces. These results provide beneficial information for the application of agrochemicals for improved wetting and spreading behavior. © 2018 Society of Chemical Industry.

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Host plants will affect the performance and population dynamics of the polyphagous insect pest Grapholitha molesta (Busck) (Lepidoptera: Tortricidae). Cultivar‐level variability needs to be considered in assessing the performance of G. molesta. We evaluated the fitness of G. molesta on five apple varieties in the laboratory by placing eggs on apples and observing their performance including survival, development, and fecundity of the adult insect. Our results demonstrated differences between indices such as larval duration, pupal weight, egg production, length of tunnel, and exiting rate of larvae, which gave similar host rankings. Variety Danxia was less suitable than Jinqing and Shuohong, and more suitable than Empire and Jinxing. However, other indices such as pupal duration, total pre‐oviposition time, and the estimated population parameters resulted in a different host ranking. We calculated weighted fitness scores to overcome the problem of inconsistent rankings. Empire changed from being the second highest ranking variety based on all population parameters to the second lowest using weighted fitness scores. The difference in ranking observed between apple varieties demonstrates the care needed in predicting population performance in the field using single traits.

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A great deal of progress has been made over the last three decades in research on pheromone-mediated mating disruption technology for the oriental fruit moth,Grapholita molesta(Busck). Pheromones can interrupt normal orientation, and the most likely mechanism of pheromone disruption, competitive-attraction (false-plume following), invokes competition between point sources of pheromone formulation and females for males. This technology, performed by broadcasting pheromones into orchards to disrupt mate finding, has been successfully implemented in oriental fruit moth control. Reservoir-style dispensers made of polyethylene tubes, which release pheromone throughout the full growing season, are the current industry standard. Although reasonably effective, they require labor-intensive hand application. Recently, a new formulation, paraffin wax, which maximizes competition between point sources of synthetic pheromone and feral females for males, was shown to have high disruption performance. As this formulation is highly effective, inexpensive, and easy to produce, further study and development are advisable. Increased understanding of the principles of mating disruption will aid in the design of more effective dispensers. Continued research is needed to meet grower concerns with regard to risk, efficacy, and cost and to identify other semiochemicals that can be applied to this delivery system. Greater knowledge of the integration of different biological control methods is therefore essential.

The establishment of standardised methods for monitoring the oriental fruit moth Grapholitha molesta (Busck) (Lepidoptera: Tortricidae) requires the identification of factors that significantly affect trap catch efficacy. We examined the effects of trap height, trap location, and inter-trap spacing on trap catches in a conventional peach orchard. Traps were placed at heights of up to 3.0 m above the ground and sets of nine traps were positioned in grids with inter-trap distances of 10–50 m to determine the optimum trap height, location, and spacing. Traps were checked daily over 10 days for males during four periods corresponding to peak moth flight. Moth catches were higher when traps were placed toward the tops (2.5 m) and outside the canopy (3.0 m). Moth catches in traps located upwind and outside tended to be higher than in the central trap for all inter-trap distances. When inter-trap distances were shorter than 30 m, interference between traps occurred. Our results provide an efficient trap distribution for monitoring G. molesta in peach orchards.