RESUMEN
Little resistance to the pea weevil insect pest (Bruchus pisorum) is available in pea (Pisum sativum) cultivars, highlighting the need to search for sources of resistance in Pisum germplasm and to decipher the genetic basis of resistance. To address this need, we screened the response to pea weevil in a Pisum germplasm collection (324 accession, previously genotyped) under field conditions over four environments. Significant variation for weevil seed infestation (SI) was identified, with resistance being frequent in P. fulvum, followed by P. sativum ssp. elatius, P. abyssinicum, and P. sativum ssp. humile. SI tended to be higher in accessions with lighter seed color. SI was also affected by environmental factors, being favored by high humidity during flowering and hampered by warm winter temperatures and high evapotranspiration during and after flowering. Merging the phenotypic and genotypic data allowed genome-wide association studies (GWAS) yielding 73 markers significantly associated with SI. Through the GWAS models, 23 candidate genes were found associated with weevil resistance, highlighting the interest of five genes located on chromosome 6. These included gene 127136761 encoding squalene epoxidase; gene 127091639 encoding a transcription factor MYB SRM1; gene 127097033 encoding a 60S ribosomal protein L14; gene 127092211, encoding a BolA-like family protein, which, interestingly, was located within QTL BpLD.I, earlier described as conferring resistance to weevil in pea; and gene 127096593 encoding a methyltransferase. These associated genes offer valuable potential for developing pea varieties resistant to Bruchus spp. and efficient utilization of genomic resources through marker-assisted selection (MAS).
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Estudio de Asociación del Genoma Completo , Pisum sativum , Gorgojos , Animales , Gorgojos/genética , Gorgojos/fisiología , Pisum sativum/genética , Pisum sativum/parasitología , Marcadores Genéticos , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/genética , Genotipo , Fenotipo , Sitios de Carácter Cuantitativo , Polimorfismo de Nucleótido SimpleRESUMEN
Hylurgus ligniperda invaded Shandong, China, through imported forest timber, posing a threat to China's forest health. Exotic insects with broad environmental tolerance, including low temperatures, may have a better chance of surviving the winters and becoming invasive. Understanding the cold-tolerance strategies of H. ligniperda may help to design sustainable pest management approaches. In this study, we aim to investigate the cold-tolerance ability and relevant physiological indicators in overwintering H. ligniperda adults to determine any possible overwintering strategies. Supercooling points (SCPs) for adults H. ligniperda differed significantly across months and reached the lowest level in the mid- and post-overwintering period, the minimum SCPs -6.45â ±â 0.18 °C. As the cold exposure temperature decreased, the survival rate of adults gradually decreased, and no adult survived more than 1 day at -15 °C, and the LLT50 for 1 day was -7.1 °C. Since H. ligniperda adults can survive internal ice formation, they are freeze-tolerant insects. Throughout the overwintering period, the SCPs and the water, protein, sorbitol, and glycerol content in adults decreased initially and then increased. We reported significant correlations between total protein, sorbitol, trehalose, and glycerol content in the beetles and SCPs. Glycogen, lipid, protein, trehalose, and sorbitol content in adult beetles may directly affect their cold-tolerance capacity and survival during winter. This study provides a physiological and biochemical basis for further study of metabolism and cold-tolerance strategies in H. ligniperda adults, which may help predict population dynamics and distribution potential of pests.
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Frío , Estaciones del Año , Gorgojos , Animales , Gorgojos/fisiología , Aclimatación , ChinaRESUMEN
Invasive pests reduce biodiversity and ecosystem service functions, thereby leading to economic and also agricultural losses. Banana skipper (Erionota torus Evans), red palm weevil (Rhynchophorus ferrugineus), and coconut caterpillar (Opisina arenosella Walker) are invasive insect pests in the palm-growing regions and they have had serious consequences for the planting of bananas (Musa nana), palms (Trachycarpus fortune) and coconut (Cocos nucifera). Based on screened occurrence data, the present research utilized Maximum Entropy model (Maxent) to simulate the distribution dynamics of these three invasive insects in China, under current and future climate (2050s, 2070s, 2090s) in two shared socio-economic pathways (SSPs: 126 and 585) of the newly released coupled model intercomparison project phase6 (CMIP6). The results show that: (1) Under current and future climate conditions, all model groups exhibited an AUC value exceeding 0.92, which shows that the model prediction results are very good;(2) The suitable habitat area of E. torus Evans remains relatively stable with some expansion in the SSP126 of 2090s and some contraction in the SSP585 of 2090s. The suitable habitat area of R. ferrugineus showed an overall contraction, with substantial contraction in the SSP585 of 2090s.The suitable habitat area of O. arenosella has an overall expansion, with the most pronounced expansion in the SSP585 of 2070s; (3) The current centroid of suitable habitats for R. ferrugineus and E. torus Evans is located in Guangxi Province and wholely shift toward the south direction under future climate. The centroid of suitable habitats for O. arenosella is currently located in the northeastern maritime area of Hainan Province and will shift toward the north direction under future climate; (4) Temperature, precipitation and Human disturbance factors (Population density and Human influence index) were crucial variables for describing the distribution of the three species. For E. torus Evans in particular, percentage contributions of Population density was up to 31.4, which is only 0.1 different from ranked first Bio19 (Precipitation of the coldest quarter). The dynamics of habitats of these three species and the correlating driver factors proposed in this work provide essential insights into future spatial management of the three invasive insects in China. Our work is necessary and timely in identifying newly areas at high risk of expansion of the three invasive insects in the future, then suggesting strategic control measures to prevent their spread, and finally providing scientific evidence for the early prevention and rapid response to the three invasive insects.
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Cambio Climático , Especies Introducidas , Gorgojos , Animales , China , Gorgojos/fisiología , Ecosistema , Agricultura , BiodiversidadRESUMEN
Sexually selected weapons used to monopolize mating opportunities are predicted to trade-off with traits used in competition for fertilization. Yet, the limited size range typically found among adults of a species often precludes clear comparisons between population-level and individual-level relative trait investment. The jousting weevil, Brentus anchorago (Coleoptera: Brentidae), varies more than 26-fold in body mass, which is among the most extreme adult body size ranges of any solitary terrestrial species. We reveal a trade-off at a population level: hypermetric scaling in male weapons (slopeâ =â 1.59) and a closely mirrored reversal in allocation to postcopulatory traits (slopeâ =â 0.54). Yet, at the individual level, we find the opposite pattern; males that invest relatively more in weapons for their size class also invest more in postcopulatory traits. Across 36 dung beetle and 41 brentine weevil species, we find the allometric slope explains more trait variation at larger body size ranges; in brentines, population-level scaling patterns become more detectable in species with a larger range in adult body size. Our findings reveal that population-level allometries and individual-level trade-offs can both be important in shaping relative trait allocation; we highlight that the adult body size range is rarely examined but may be integral to gaining a deeper understanding of trade-offs in reproductive allocation.
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Tamaño Corporal , Gorgojos , Animales , Masculino , Gorgojos/fisiología , Gorgojos/anatomía & histología , Femenino , Preferencia en el Apareamiento Animal , Escarabajos/fisiología , Escarabajos/anatomía & histología , Selección SexualRESUMEN
Regional variation in pheromone production and response has practical implications for the use of semiochemical lures to monitor and control bark beetle populations. We tested 4 lure formulations including 2 new formulations that reflect the pheromone production profiles of western and eastern populations of spruce beetles, Dendroctonus rufipennis Kirby (Coleoptera: Curculionidae), as well as 2 commercially available formulations (current Rocky Mountain lure and current Atlantic lure), in 2 locations in New Brunswick, Canada. In 2 separate years, the new eastern lure containing seudenol, MCOL, and spruce terpenes captured 4 times (2021) and 11 times (2022) more spruce beetles than the current Atlantic lure that consisted of frontalin, seudenol, and spruce terpenes. In 2021, we also captured more eastern larch beetles, Dendroctonus simplex LeConte (Coleoptera: Curculionidae), with the new eastern lure, whereas in 2022, we captured the most D. simplex with the current Atlantic lure, suggesting that more research is needed on D. simplex pheromone production and response across its range. The bark beetle predator, Thanasimus dubius (Fabr.; Coleoptera: Cleridae), did not respond well to the new eastern blend that lacks frontalin, suggesting that response to frontalin is important in finding prey and might be conserved in predator populations. The reduced trap catch of T. dubius to the enhanced lure is beneficial because it does not inhibit natural population control by removing predators from the community. Our study reveals an improved trap lure for eastern populations of spruce beetles and highlights gaps and research needs in bark beetle pheromone ecology.
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Feromonas , Gorgojos , Animales , Gorgojos/fisiología , Gorgojos/efectos de los fármacos , Feromonas/farmacología , Control de Insectos , Nuevo Brunswick , Femenino , MasculinoRESUMEN
The impacts of climate change on the development of insects are of great concern due to potential alterations in population dynamics and pest pressure. The carrot weevil, Listronotus oregonensis, is a major agricultural pest, and its development is influenced by temperature and photoperiod. In this study, our aim was to investigate the impact of temperature increases on the voltinism and reproductive diapause of the carrot weevil under field conditions and bioclimatic models. Field observations were conducted over two growing seasons using structures that allowed for temperature increases. The developmental stages of the carrot weevil, including female reproductive status, oviposition and larval stage, were monitored weekly to measure the proportion of individuals undergoing an additional generation. Concurrently, bioclimatic models were used to simulate the probability of a second generation under current (1981-2010) and future (2041-2070) climates, considering a lower and a higher change in emission scenarios. Results showed that rising temperatures led to an increase in the proportion of carrot weevils undergoing inhibition of the reproductive diapause and a higher number of eggs laid in the field. The models indicated a substantial rise in the probability of a second generation developing, from 24% to 37% to 62%-99% under current and future climates, respectively. These findings demonstrate the potential for significant alterations in carrot weevil population dynamics, resulting in increased pest pressure on crops. Further research is needed to fully understand the implications of these findings and to develop effective adaptation measures to mitigate the negative impacts of global warming on insect populations and agriculture.
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Cambio Climático , Diapausa de Insecto , Gorgojos , Animales , Gorgojos/fisiología , Gorgojos/crecimiento & desarrollo , Diapausa de Insecto/fisiología , Femenino , Reproducción , Oviposición , Temperatura , Larva/crecimiento & desarrollo , Larva/fisiologíaRESUMEN
PREMISE: During the last centuries, the area covered by urban landscapes is increasing all over the world. Urbanization can change local habitats and decrease connectivity among these habitats, with important consequences for species interactions. While several studies have found a major imprint of urbanization on plant-insect interactions, the effects of urbanization on seed predation remain largely unexplored. METHODS: We investigated the relative impact of sunlight exposure, leaf litter, and spatial connectivity on predation by moth and weevil larvae on acorns of the pedunculate oak across an urban landscape during 2018 and 2020. We also examined whether infestations by moths and weevils were independent of each other. RESULTS: While seed predation varied strongly among trees, seed predation was not related to differences in sunlight exposure, leaf litter, or spatial connectivity. Seed predation by moths and weevils was negatively correlated at the level of individual acorns in 2018, but positively correlated at the acorn and the tree level in 2020. CONCLUSIONS: Our study sets the baseline expectation that urban seed predators are unaffected by differences in sunlight exposure, leaf litter, and spatial connectivity. Overall, our findings suggest that the impact of local and spatial factors on insects within an urban context may depend on the species guild. Understanding the impact of local and spatial factors on biodiversity, food web structure, and ecosystem functioning can provide valuable insights for urban planning and management strategies aimed at promoting urban insect diversity.
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Ecosistema , Mariposas Nocturnas , Quercus , Semillas , Gorgojos , Animales , Semillas/fisiología , Mariposas Nocturnas/fisiología , Gorgojos/fisiología , Quercus/fisiología , Larva/fisiología , Urbanización , Ciudades , Luz Solar , Cadena AlimentariaRESUMEN
Eucryptorrhynchus scrobiculatus (Motschulsky) (Coleoptera: Curculionidae) is a notorious pest of Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae). E. scrobiculatus adults typically aggregate under leaves and in soil crevices at the base of A. altissima in the field. We hypothesize that the environmental factors and conspecific signals determine their aggregation behavior. To test this, we investigated adult numbers in light-exposed and shaded areas of the sample trees and conducted experiments in both field and lab settings. Results revealed that (i) greater adult distribution in shaded areas; (ii) significant influence of temperature and illumination on aggregation tendency in the field; (iii) no gender-based difference in aggregation degree and maximum aggregation between light and dark; (iv) the host plant triggering the aggregation tendency, negatively affected in the absence; (v) the aggregation tendency of E. scrobiculatus weakened with the temperature gradually changing to ordinary temperature; and (vi) mutual attraction and chemical attraction between males and females. Thus, the aggregation behavior was influenced by factors including temperature, light intensity, host plant, and conspecific signals, but light's role was not obvious in the lab.
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Temperatura , Gorgojos , Animales , Gorgojos/fisiología , Femenino , Masculino , Ailanthus , Luz , Conducta AnimalRESUMEN
The technique of terrestrial sampling of boll weevil (BW) populations is expensive and inefficient over large areas, but may be cheaper and more efficient without involving the manipulation of cotton squares. The aim of this study was to develop a technique to sampling cotton squares based on the observation of opened and/or yellowing bracts to determine the need and efficacy of chemical control of BW in cotton crops. The first experiment aimed to estimate the ratio between the number of cotton squares with opened and/or yellowed bracts and that of squares with BW oviposition punctures. The second experiment, aimed to determine the efficacy of chemical control for BW by sampling cotton squares with opened and/or yellowed bracts. The ratio between the number of opened and/or yellowed bracts and the number of cotton squares with oviposition punctures was 2:1. The level and efficiency of chemical control of BW, based on the percentage and sampling of cotton plants with opened and/or yellowed bracts, was 5% and did not differ from the one based on the observation of cotton plants with 10% cotton squares with oviposition punctures by BW females. The control level based on sampling cotton plants with open and/or yellowing bracts was 5%. The efficiency of chemical insecticides using this economic threshold against the BW did not differ from that based on sampling cotton plants with 10% of cotton squares with oviposition punctures by BW females. This indicates that the chemical control of cotton boll weevil can be carried out based on cotton squares with open and/or yellowed bracts.
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Gossypium , Control de Insectos , Oviposición , Gorgojos , Gorgojos/fisiología , Gossypium/parasitología , Animales , Oviposición/fisiología , Femenino , Control de Insectos/métodos , InsecticidasRESUMEN
The significance of ecological non-monotonicity (a function whose first derivative changes signs) in shaping the structure and functions of the ecosystem has recently been recognized, but such studies involving high-order interactions are rare. Here, we have proposed a three-trophic conceptual diagram on interactions among trees, rodents, and insects in mast and non-mast years and tested the hypothesis that oak (Quercus wutaishanica) masting could result in increased mutualism and less predation in an oak-weevil-rodent system in a warm temperate forest of China. Our 14-year dataset revealed that mast years coincided with a relatively low rodent abundance but a high weevil abundance. Masting not only benefited seedling recruitment of oaks through increased dispersal by rodents but also a decrease in predation by rodents and weevils, as well as an increase in the overwintering survival of rodents. Masting appeared to have increased weevil survival by reducing predation of infested acorns by rodents. These results suggest that masting benefits all participants in the plant-insect-rodent system by increasing mutualism and reducing predation behavior (i.e., a non-monotonic function). Our study highlights the significance of masting in maintaining the diversity and function of the forest ecosystem by facilitating the transformation from predation to mutualism among trophic species.
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Conducta Predatoria , Quercus , Roedores , Simbiosis , Gorgojos , Animales , Quercus/fisiología , Gorgojos/fisiología , Conducta Predatoria/fisiología , Roedores/fisiología , China , Ecosistema , Bosques , Cadena AlimentariaRESUMEN
A major challenge to area-wide management of coffee berry borer (Hypothenemus hampei Ferrari) (Coleoptera: Scolytidae) is understanding how a heterogeneous coffee-growing landscape affects coffee berry borer population dynamics across temporal and spatial scales. We examined coffee phenology, weather, coffee berry borer flight activity, infestation, coffee berry borer position within the fruit, and management across 14 commercial coffee farms from 2016 to 2018 on Hawaii Island to characterize variation among districts and elevations. Here we aim to determine whether the timing of pesticide applications might be optimized based on specific locations. We observed larger populations of coffee berry borer at low-elevation farms and in the Kona district compared to mid- and high-elevation farms and the Ka'u district. Temperature, relative humidity, and rainfall all differed significantly across districts and elevations. We also observed a trend of higher fruit production at low-elevation farms compared to high-elevation farms, and differences in the timing of fruit development. Infestation increased with higher pest pressure and air temperatures and reduced fruit availability early and late in the season. Lastly, the timing and number of management interventions varied among districts and elevations. Combining information on trap catch, infestation, coffee berry borer position, and plant phenology, we present an optimized pesticide spray schedule for each location and find that the number of sprays could be reduced by 33-75% in comparison to the existing integrated pest management recommendations while maintaining effective control. Implementing a coordinated area-wide approach refined by small-scale optimization will lead to improved management of coffee berry borer on individual farms and a reduction in pest pressure across the coffee-growing landscape.
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Coffea , Control de Insectos , Dinámica Poblacional , Animales , Hawaii , Control de Insectos/métodos , Coffea/crecimiento & desarrollo , Gorgojos/fisiología , Insecticidas/farmacología , Estaciones del Año , Escarabajos/fisiologíaRESUMEN
Euwallacea fornicatus is an invasive tree pest able to infest healthy plants and cause damage to many host plants. This beetle has become established in several countries where it was introduced. It has now become established in Brazil, and while the original introduction site remains uncertain, there is a possibility of multiple introductions. We report the first evidence for the establishment of E. fornicatus with molecular confirmation, as well as its distribution, and host plants in Brazil. Euwallacea fornicatus has spread to main commercial avocado groves, other monocultures, and native vegetation in the country, and its pest status puts it as a threat, mainly to Brazilian avocado producers.
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Distribución Animal , Especies Introducidas , Persea , Gorgojos , Animales , Gorgojos/fisiología , BrasilRESUMEN
This study emphasizes the phytochemical study of some locally available botanicals against maize weevils. Nine plant parts were collected from six plant species. The test plant powder (200 g) was suspended sequentially in 600 ml of petroleum ether, chloroform, acetone, methanol, and distilled water for 72 h with frequent agitation. Different concentrations of the crude extracts were applied to maize seeds at rates of 10 ml, 15 ml and 20 ml per 100 g. All treatments with different extracts at different rates of application showed significant differences (p < 0.05) in the cumulative mean percentage mortality of the maize weevil. The seed extract of Maesa lanceolata and Croton macrostachyus and the leaf extract of Clausena anisata showed cumulative percent mortality ranged 95.32-98.02% in 28 days after treatment application. There was no significant difference (p > 0.05) among all treatments for the prevention of F1 progeny emergence. In all extracts, Clausena anisata showed 100% inhibition of F1 progeny emergence. All treatments significantly reduced seed weight loss and damage. The treated maize seeds were germinated with an acceptable germination quality. In conclusion, an increased dosage of the extract resulted in significant mortality in maize weevils. The seed extracts of Maesa lanceolata and Croton macrostachyus and Clausena anisata leaf extract were observed to be the most promising botanical in protecting stored maize against maize weevil.
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Escarabajos , Insecticidas , Plantas Medicinales , Gorgojos , Animales , Gorgojos/fisiología , Insecticidas/farmacología , Fitoquímicos/farmacología , Extractos Vegetales/farmacologíaRESUMEN
The diel flight activity in Cathartus quadricollis (Guerin-Meneville) (Coleoptera: Silvanidae), a predator of two important pests in Hawaii, coffee berry borer, Hypothenemus hampei (Ferrari) and tropical nut borer, Hypothenemus obscurus (F.) (Coleoptera: Curculionidae: Scolytinae) was studied in a macadamia nut orchard using yellow sticky traps baited with pheromone and fungal volatile attractants. The study was conducted at different months throughout the year and at different times during the lunar cycle (new moon and full moon). Flight activity peaked in the late hours of the photophase into the early hours of the scotophase, between 1830 and 2000 h; flight activity also occurred but to a lesser extent in the early morning hours between 0700 and 1030 h. Numbers of captured C. quadricollis during periods of flight activity were negatively correlated with wind speed. The implications of these findings for the development of optimal pest management strategies including biological control are discussed.
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Coffea , Escarabajos , Gorgojos , Animales , Escarabajos/fisiología , Macadamia , Hawaii , Gorgojos/fisiologíaRESUMEN
The southern pine beetle, Dendroctonus frontalis Zimmermann is an important mortality agent of Pinus in the eastern United States of America where it commonly shares hosts with the black turpentine beetle, Dendroctonus terebrans (Olivier), which infrequently kills trees. Unlike D. frontalis, which must kill its hosts to become established in the bark and reproduce, D. terebrans can occupy living hosts as a parasite. Olfactory mechanisms whereby D. frontalis initially locates hosts have not been demonstrated, whereas D. terebrans responds strongly to host odors. Because D. terebrans produces frontalin, the primary aggregation pheromone component for D. frontalis, and commonly arrives on hosts prior to D. frontalis, it has been hypothesized that D. terebrans pheromone components can mediate D. frontalis location of suitable, living trees. We assessed this possibility with studies of the semiochemical interactions between D. frontalis and D. terebrans. Coupled gas chromatography-electroantennographic detection analyses indicated that D. terebrans produces nine different olfactory stimulants for D. frontalis, nearly all of them known semiochemicals for D. frontalis. A trapping experiment designed to address the potentially confounding influence of lure contamination confirmed that the D. terebrans pheromone component exo-brevicomin enhances attraction of D. frontalis and thus could be an attractive kairomone. In ambulatory bioassays, male D. frontalis were strongly attracted to odors of frass of solitary female and paired D. terebrans, indicating their attraction to the naturally occurring semiochemicals of D. terebrans. Cues from D. terebrans may influence host and mate-finding success of D. frontalis and, thereby, the latter's virulence.
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Feromonas , Pinus , Gorgojos , Animales , Gorgojos/fisiología , Feromonas/farmacología , Femenino , Masculino , Interacciones Huésped-ParásitosRESUMEN
Gaining the ability to fly actively was a ground-breaking moment in insect evolution, providing an unprecedented advantage over other arthropods. Nevertheless, active flight was a costly innovation, requiring the development of wings and flight muscles, the provision of sufficient energetic resources, and a complex flight control system. Although wings, flight muscles, and the energetic budget of insects have been intensively studied in the last decades, almost nothing is known regarding the flight-control devices of many crucial insect groups, especially beetles (Coleoptera). Here, we conducted a phylogenetic-informed analysis of flight-related mechanosensors in 28 species of bark beetles (Curculionidae: Scolytinae, Platypodinae), an economically and ecologically important group of insects characterized by striking differences in dispersal abilities. The results indicated that beetle flight apparatus is equipped with different functional types of mechanosensors, including strain- and flow-encoding sensilla. We found a strong effect of allometry on the number of mechanosensors, while no effect of relative wing size (a proxy of flight investment) was identified. Our study constitutes the first step to understanding the drivers and constraints of the evolution of flight-control devices in Coleoptera, including bark beetles. More research, including a quantitative neuroanatomical analysis of beetle wings, should be conducted in the future.
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Escarabajos , Gorgojos , Animales , Gorgojos/fisiología , Filogenia , Corteza de la Planta , Escarabajos/fisiología , Alas de Animales/fisiología , Vuelo Animal/fisiologíaRESUMEN
BACKGROUND: Montana accounts for approximately 45% of US dry pea production and the pea leaf weevil (PLW; Sitona lineatus (L.)) is the most common insect pest in this region. After crop emergence adult PLW feed on the foliage to mature and subsequently mate, and the soil-dwelling larvae feed and develop on the nitrogen-fixing root nodules. Producers commonly apply prophylactic insecticide treatments to the seed at planting as well as one or two post-emergent insecticide sprays to control PLW damage. To develop alternative management strategies based on integrated pest management (IPM), this field study evaluated pulse crops grown in Montana for adult feeding preference and larval development. Ten different field pea varieties, along with two faba bean, lentil and chickpea varieties, were evaluated during the 2020 and 2021 field seasons at the Montana State University Arthur H. Post Agronomy Farm. RESULTS: Significant PLW pest pressure was observed within the research plots during both experimental years. Field pea and faba bean were preferred by the foliage feeding adult stage, with all but one variety averaging 39.2 to 86.3 average notches per plant. The pea variety Lifter was significantly preferred over all other comparisons, averaging 142.4 and 95.0 notches per plant in 2020 and 2021, respectively. Adult PLW feeding on lentil and chickpea was minimal, averaging 3.3 to 8.2 and 0.5 to 1.6 notches per plant, respectively. Numbers of larvae were highest on the roots of pea varieties, a known reproductive host, and almost nil on lentil and chickpea roots. Faba bean is also known as reproductive host, but, unexpectedly, larval populations were also low on the two faba bean varieties. CONCLUSIONS: The results from this study provide some limited evidence for alternative IPM strategies for field peas based on host plant tolerance or resistance within the range of varieties tested. Adult preference and larval development of PLW varied between the different pulse crops with field peas and faba beans being the most susceptible and lentils and chickpeas being the least susceptible. Host plant resistance against PLW could provide more sustainable IPM approaches in the future. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Larva , Pisum sativum , Gorgojos , Animales , Gorgojos/crecimiento & desarrollo , Gorgojos/fisiología , Larva/crecimiento & desarrollo , Larva/fisiología , Pisum sativum/crecimiento & desarrollo , Montana , Lens (Planta)/crecimiento & desarrollo , Cicer/crecimiento & desarrollo , Productos Agrícolas/crecimiento & desarrollo , Vicia faba/crecimiento & desarrollo , Conducta AlimentariaRESUMEN
BACKGROUND: Dendroctonus valens along with its symbiotic fungi have caused unprecedented damage to pines in China. Leptographium procerum, its primary symbiotic fungus, facilitates the invasion and colonization of the pest, thereby aggravating ecological threats. Assessing shifts in the niches and ranges of D. valens and its symbiotic fungus could provide a valuable basis for pest control. Here, we conducted niche comparisons between native and invasive populations of D. valens. Then, we employed standard ecological niche models and ensembles of small models to predict the potential distributions of D. valens and L. procerum under climate change conditions and to estimate areas of overlap. RESULTS: The niche of invasive population of D. valens in Chinese mainland only occupied a limited portion of the niche of native population in North America, leaving a substantial native niche unfilled and without any niche expansion. The suitable regions for D. valens are predicted in central and southern North America and central and northeastern Chinese mainland. The overlap with the suitable regions of L. procerum included eastern North America and the central and northeastern Chinese mainland under historical climatic scenarios. The regions susceptible to their symbiotic damage will shift northward in response to future climate change. CONCLUSIONS: Projected distributions of D. valens and its symbiotic fungus, along with areas vulnerable to their symbiotic damage, provide essential insights for devising strategies against this association. Additionally, our study contributes to comprehending how biogeographic approaches aid in estimating potential risks of pest-pathogen interactions in forests within a warming world. © 2024 Society of Chemical Industry.
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Cambio Climático , Simbiosis , Gorgojos , Animales , China , Gorgojos/microbiología , Gorgojos/fisiología , Especies Introducidas , Escarabajos/microbiología , Escarabajos/fisiología , Modelos Biológicos , Ecosistema , Distribución Animal , Pinus/parasitología , Pinus/microbiologíaRESUMEN
Leptographium procerum has been demonstrated to play important roles in the invasive success of red turpentine beetle (RTB), one of the most destructive invasive pests in China. Our previous studies found that bacterial volatile ammonia plays an important role in the maintenance of the RTB-L. procerum invasive complex. In this study, we found a GPCR gene Gpr-1 that was a response to ammonia but not involved in the ammonia-induced carbohydrate metabolism. Deletion of Gpr-1 significantly inhibited the growth and pathogenicity but thickened the cell wall of L. procerum, resulting in more resistance to cell wall-perturbing agents. Further analyses suggested that Gpr-1 deletion caused growth defects that might be due to the dysregulation of the amino acid and lipid metabolisms. The thicker cell wall in the ΔGpr-1 mutant was induced through the cell wall remodeling process. Our results indicated that Gpr-1 is essential for the growth of L. procerum by regulating the nutritional metabolism, which can be further explored for potential applications in the management of RTB.
Asunto(s)
Escarabajos , Ophiostomatales , Gorgojos , Animales , Amoníaco , Corteza de la Planta , Simbiosis , Gorgojos/fisiología , Ophiostomatales/genética , Escarabajos/genética , Receptores Acoplados a Proteínas G/genéticaRESUMEN
BACKGROUND: Insect pest resistance to insecticides and societal pressure to reduce pesticide load has increased oilseed rape (OSR) farmers' motivation to protect and exploit parasitoids for pest control. However, parasitoid presence and parasitism must be made visible to influence farmers' spraying decisions. Parasitism of cabbage seed weevil (CSW) (Ceutorhynchus obstrictus (Marsham)) reduces damage to OSR immediately, making them a good case for demonstrating conservation biocontrol to farmers. We assessed the occurrence and activity of CSW parasitoids in 84 OSR fields over 2 years and identified the impact of associated local landscape factors. RESULTS: Mean cabbage seed weevil infestation rates were 11% and 10% in 2020 and 2021, and parasitism rates were high in both years (75% and 74%, respectively). Temporal and spatial dynamics of OSR in the landscape surrounding the focal fields were important for both CSW and parasitoid numbers, suggesting a dilution effect for increasing OSR area since the previous year. A multimodel inference analysis showed that OSR-related factors were important predictors for both the infestation rate of CSW and the number of parasitoids. For parasitoids, protected nature areas and hedgerows were important. Parasitism rates were high and largely unaffected by landscape factors. CONCLUSION: CSW and its parasitoids respond similarly to interannual changes in the OSR resource; in addition, parasitoids benefit from uncropped areas in the surrounding landscape. The complexity of the pest and parasitoid response to landscape factors limits the prospect of designing landscapes for improved pest control by the parasitoids. Parasitoids of CSW may be present as local populations in agricultural landscapes with the potential for consistent and substantial parasitism. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.