Search Results (14)

It is widely recognized that the phenology of insects, of which the life activities are closely tied to temperature, is shifting in response to global climate warming. This study aimed to investigate the impacts of climate change on the phenology of Carposina sasakii Matsumura, 1900 (Lepidoptera: Carposinidae) across large temporal and spatial scales, through collecting and systematically analyzing historical data on the pest’s occurrence and population dynamics in China. The results showed that for overwintering adults, the first occurrence date in eastern, northwestern, and northern China has significantly advanced, along with the population peak in eastern and northwestern China. At the provincial level, the population peak date in Shandong province has also moved significantly earlier, as well as the population peak date in Shandong and Shaanxi and the end occurrence date in Ningxia. However, the population peak date in Jilin has experienced a delayed trend. For first-generation adults, the first occurrence date in northeastern, eastern, and central China has notably advanced, while the first appearance date in northwestern and northern China has significantly delayed. Additionally, the population peak in northwestern China has experienced significant delays, along with the final occurrence in northeastern and northwestern China. At the provincial level, the first occurrence date in Liaoning, Shandong, and Shanxi has significantly advanced, while Hebei has demonstrated a significant delay. The population peak time in Gansu and Shaanxi has displayed significant delays, and the end occurrence date in Liaoning, Shanxi, and Shaanxi has also shown significant delays. Furthermore, these findings integrated with the Pearson correlation results reveal spatial heterogeneity in C. sasakii’s phenological responses to climate warming at both regional and provincial scales. The phenology of C. sasakii and their changing patterns with climate warming vary by geographical location. This study provides valuable information for the future monitoring, prediction, and prevention of peach fruit moths in the context of climate warming. Full article

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. Full article

The peach fruit moth, Carposina sasakii, is part of the Carposinidae, and is harmful to the families Rosaceae and Rhamnaceae. C. sasakii lays eggs on the hairy surface of the fruit’s stalk cavity and calyx end. After hatching, the moth can bore into the fruits and feed on the flesh inside. Chemosensory proteins (CSPs) are a class of low-molecular-weight soluble carrier proteins that are highly evolutionarily conserved. To enhance our understanding of the recognition of host plant volatiles by CSPs of C. sasakii, the expression patterns and binding characteristics of CsasCSP7, CsasCSP9 and CsasCSP11 in C. sasakii were investigated. In our study, the results of real-time quantitative polymerase chain reaction (qPCR) assays demonstrate that CsasCSP7 and CsasCSP9 transcripts were abundantly expressed in the antennae of males, and CsasCSP11 was highly expressed in the wings of females. Fluorescence competitive binding assays with 38 candidate ligands showed that CsasCSP7 could bind to benzaldehyde and dodecanal, whereas CsasCSP9 bound to butyl octanoate, decanal and (-)-beta-pinene. CsasCSP11 could also bind to1-hexanol, beta-ocimene and 6-methyl-5-hepten-2-one. Our results suggest that CsasCSP7, CsasCSP9 and CsasCSP11 may play a crucial role in locating the host plant of C. sasakii. Full article

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. Full article

Grapholita molesta (Busck) (Lepidoptera: Tortricidae), Oriental fruit moth (OFM), attacks fruits and shoots of the economically important trees in Rosaceae. Amygdalin is a cyanogenic glucoside of rosaceous plants that may be related to the seasonal patterns of infestation in many pests. The amygdalin concentration of fruits and shoots of peach, pear, and apple varies over the growing season. However, the relationship between the amygdalin concentration and G. molesta performance has not been reported. Here, we measured the performance (feeding, growth, development, and fecundity) of G. molesta larvae (as subsequent adults) reared on artificial diets with six amygdalin concentrations (0, 3, 6, 12, 24, and 48 mg/g), and we then calculated the population parameters. We found that these different concentrations of amygdalin affected the developmental time and fecundity, except for the proportion of larvae feeding on the diet and the survival rates of larvae and pupae. When compared with the control diet without amygdalin, diets with 3 or 6 mg/g (low and moderate concentrations) of amygdalin shortened developmental times and increased the number of eggs laid by females; however, a diet with 12 mg/g (moderate concentration) of amygdalin only increased the number of eggs laid by females and did not affect the larval and pupal developmental rate. A diet with 48 mg/g (high concentration) of amygdalin prolonged developmental times and reduced the number of eggs laid by females when compared with the control diet without amygdalin. Furthermore, the intrinsic rate of increase (r_m) for insects reared on diets with 3 or 6 mg/g (low and moderate concentrations) of amygdalin versus the control diet without amygdalin showed a slightly improved population growth. However, this increase in the r_m value did not persist over ten successive generations of rearing on the same diet. We concluded that the diet with 6 mg of amygdalin per g of diet can enhance the performance and population growth of G. molesta, but the effects of amygdalin are concentration-dependent. Full article

The fumigation of apples using methyl bromide (MeBr) can cause severe deterioration in fruit quality. Moreover, maintaining the quality of apples during postharvest storage and eradicating pests, especially those involved in quarantine issues, are important for facilitating the export of apples, including the “Fuji” apple (Malus pumila var. “Fuji”) in South Korea. In the present study, phosphine (PH₃) fumigation as an alternative to MeBr was found to be more effective for the control of peach fruit moth larvae (Carposina sasakii), which had naturally infested Fuji apples, at a high temperature (25 °C) rather than at a low temperature (5 °C). To achieve the industry requirement of better-quality perishable commodities and meet quarantine guidelines for export, PH₃ fumigation at the low temperature (5 °C) was followed by cold treatments at 3 ± 2 °C for 2 and 4 weeks, which led to higher efficacy than was achieved using PH₃ at 5 °C alone. Given that chemical treatments, such as treatment with 1-methylcyclopropene, can inhibit ethylene synthesis, low-temperature PH₃ fumigation for 72 h followed by 4 weeks of cold treatment could also extend the shelf life of apples and resolve known quarantine issues when used as an alternative to MeBr treatment. Full article

Intestinal symbiotic bacteria have played an important role in the digestion, immunity detoxification, mating, and reproduction of insects during long-term coevolution. The oriental fruit moth, Grapholita molesta, is an important fruit tree pest worldwide. However, the composition of the G. molesta microbial community, especially of the gut microbiome, remains unclear. To explore the differences of gut microbiota of G. molesta when reared on different host plants, we determined the gut bacterial structure when G. molesta was transferred from an artificial diet to different host plants (apples, peaches, nectarines, crisp pears, plums, peach shoots) by amplicon sequencing technology. The results showed that Proteobacteria and Firmicutes are dominant in the gut microbiota of G. molesta. Plum-feeding G. molesta had the highest richness and diversity of gut microbiota, while apple-feeding G. molesta had the lowest. PCoA and PERMANOVA analysis revealed that there were significant differences in the gut microbiota structure of G. molesta on different diets. PICRUSt2 analysis indicated that most of the functional prediction pathways were concentrated in metabolic and cellular processes. Our results confirmed that gut bacterial communities of G. molesta can be influenced by host diets and may play an important role in host adaptation. Full article

Almonds and pistachios are fed upon by a diverse assemblage of lepidopteran insects, several of which are economically important pests. Unfortunately, identification of these pests can be difficult, as specimens are frequently damaged during collection, occur in traps with non-target species, and are morphologically similar up to their third instar. Here, we present a quantitative PCR based melt curve analysis for simple, rapid, and accurate identification of six lepidopteran pests of almonds and pistachios: navel orangeworm (Amyelois transitella), peach twig borer (Anarsia lineatella), oriental fruit moth (Grapholita molesta), obliquebanded leafroller (Choristoneura rosaceana), raisin moth (Cadra figulilella), and Indian meal moth (Plodia interpunctella). In this approach, the dissociation (melt) temperature(s) of a 658 bp section of cytochrome c oxidase subunit 1 was determined using quantitative PCR (qPCR). Within these six species, the distribution and the number of melt peak temperatures provide an unambiguous species level identification that is reproducible when unsheared DNA can be extracted. The test is robust across a variety of sampling approaches including insects removed from sticky card traps, museum specimens, and samples that were left in the field for up to 7 days. The melt curve’s simplicity allows it to be performed in any basic molecular biology laboratory with a quantitative PCR. Full article

Conogethes pinicolalis has long been considered as a Pinaceae-feeding type of the yellow peach moth, C. punctiferalis, in Korea. In this study, the divergence of C. pinicolalis from the fruit-feeding moth C. punctiferalis was analyzed in terms of morphology, ecology, and genetics. C. pinicolalis differs from C. punctiferalis in several morphological features. Through field observation, we confirmed that pine trees are the host plants for the first generation of C. pinicolalis larvae, in contrast to fruit-feeding C. punctiferalis larvae. We successfully reared C. pinicolalis larvae to adults by providing them pine needles as a diet. From a genetic perspective, the sequences of mitochondrial COI of these two species substantially diverged by an average of 5.46%; moreover, phylogenetic analysis clearly assigned each species to an independent clade. On the other hand, nuclear EF1α showed a lower sequence divergence (2.10%) than COI. Overall, EF1α-based phylogenetic analysis confirmed each species as an independent clade, but a few haplotypes of EF1α indicated incomplete lineage sorting between these two species. In conclusion, our results demonstrate that C. pinicolalis is an independent species according to general taxonomic criteria; however, analysis of the EF1α sequence revealed a short divergence time. Full article

Numerous gut microbes are associated with insects, but their composition remains largely unknown for many insect groups, along with factors influencing their composition. Here, we compared gut bacterial microbiota of two co-occurring agricultural pests, the peach fruit moth (PFM), Carposina sasakii, and the oriental fruit moth (OFM), Grapholita molesta, collected from different orchards and host plant species. Gut microbiota of both species was mainly composed of bacteria from Proteobacteria, followed by Firmicutes. The two species shared bacteria from the genera Pseudomonas, Gluconobacter, Acetobacter, and Pantoea. When we compared two pairs of PFM and OFM populations collected from the same host species and the same orchard, there is no difference in alpha and beta diversity in gut microbiota. When we compared gut microbiota of the same species and host plant from different orchards, alpha and beta diversity was different in populations of PFM collected from two pear orchards but not in other comparisons. Our study suggests that the two pests share many features of gut microbiota and environment in orchards is a main factor influencing their gut microbiota. Full article

The Chilean plants Discaria chacaye, Talguenea quinquenervia (Rhamnaceae), Peumus boldus (Monimiaceae), and Cryptocarya alba (Lauraceae) were evaluated against Codling moth: Cydia pomonella L. (Lepidoptera: Tortricidae) and fruit fly Drosophila melanogaster (Diptera: Drosophilidae), which is one of the most widespread and destructive primary pests of Prunus (plums, cherries, peaches, nectarines, apricots, almonds), pear, walnuts, and chestnuts, among other. Four benzylisoquinoline alkaloids (coclaurine, laurolitsine, boldine, and pukateine) were isolated from the above mentioned plant species and evaluated regarding their insecticidal activity against the codling moth and fruit fly. The results showed that these alkaloids possess acute and chronic insecticidal effects. The most relevant effect was observed at 10 µg/mL against D. melanogaster and at 50 µg/mL against C. pomonella, being the alteration of the feeding, deformations, failure in the displacement of the larvae in the feeding medium of D. melanogaster, and mortality visible effects. In addition, the docking results show that these type of alkaloids present a good interaction with octopamine and ecdysone receptor showing a possible action mechanism. Full article

Monitoring oriental fruit moth Grapholita molesta Busck (Lepidoptera: Tortricidae), populations based on counts in sex pheromone-baited traps within sex pheromone-treated orchards for mating disruption (MD) is challenging since male orientation to traps is disrupted. In this study, we evaluated a new commercial pheromone–kairomone combination lure for G. molesta (Pherocon^® OFM Combo™ Dual™), which combines the G. molesta and Cydia pomonella L. sex pheromones with a blend of acetic acid and terpinyl acetate. Trap comparisons were performed in 33 trials in peach and nectarine orchards under MD (24) or non-MD (9) during the 2018–2019 period in Italy. Male and total moth captures in traps baited with the combination lure were significantly greater than in traps with G. molesta pheromone in both years and across both pheromone treatments. The proportion of females in the total moth captures using the combination lure averaged ca. 7% across all trials. The by-catch of non-targets, i.e., Apis mellifera L., was low in traps baited either with the combination and the sex pheromone lure, while trap color (white) affected the capture of beneficials but not of the target pest. Our study proves that this combination lure can improve the monitoring and management for G. molesta in stone fruits. New studies are needed to define action thresholds to trigger supplemental control methods to MD. Secondly, female-based monitoring lures should be further developed to improve management strategies. Full article

Sugar–acetic acid–ethanol–water mixture (SAEWM) trapping has initially shown the potential efficacy for monitoring or trapping insects. It is unknown how SAEWM-baited traps affect field number of oriental fruit moth (OFM), Grapholita molesta (Busck) (Lepidoptera: Tortricidae), the female/male ratio trapped, and the type of natural-enemy insects captured. This study investigated changes in seasonal population dynamics and diurnal flight rhythm of OFM, the number and female/male ratio of OFM and the numbers of Coccinellidae and Chrysopidae trapped by SAEWM in peach–apple mixed-planting orchards. The SAEWM performed well in trapping OFM, most of which were adult females, with the maximum trapping at 2.5 m above ground. The daily trapping peak occurred between 18:00 and 20:00, during each continuous monitoring period, with another peak occurring at 4:00–8:00, after the second monitoring period (2–5 July). However, the use of SAEWM also resulted in the trapping of Coccinellidae and Chrysopidae, of which peak trapping time partially overlapped with the second and third peak trapping times of OFM. We suggest the cessation of SAEWM trapping during the peak activity time of Coccinellidae and Chrysopidae, or application of alternative attractive mixture that do not trap the natural enemy insects, in order to protect the ecological balance in the field. Full article

The peach fruit moth Carposina sasakii is an economically important pest on dozens of fruits from Rosaceae and Rhamnaceae in Northeast Asia. We developed novel microsatellite markers for C. sasakii from randomly sequenced regions of the genome using next-generation sequencing. In total, 95,153 microsatellite markers were isolated from 4.70 GB genomic sequences. Thirty-five polymorphic markers were developed by assessing in 63 individuals from two geographical populations. The allele numbers ranged from 2 to 9 with an average value of 4.60 per locus, while the polymorphism information content ranged from 0.075 to 0.696 with an average value of 0.407. Furthermore, the observed and expected heterozygosity varied from 0.000 to 0.677 and 0.062 to 0.771, respectively. The microsatellites developed provide abundant molecular markers for investigating genetic structure, genetic diversity, and existence of host-plant associated biotypes of C. sasakii. Full article