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1.
iScience ; 26(9): 107462, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37636074

RESUMEN

One Biosecurity is an interdisciplinary approach to policy and research that builds on the interconnections between human, animal, plant, and ecosystem health to effectively prevent and mitigate the impacts of invasive alien species. To support this approach requires that key cross-sectoral research innovations be identified and prioritized. Following an interdisciplinary horizon scan for emerging research that underpins One Biosecurity, four major interlinked advances were identified: implementation of new surveillance technologies adopting state-of-the-art sensors connected to the Internet of Things, deployable handheld molecular and genomic tracing tools, the incorporation of wellbeing and diverse human values into biosecurity decision-making, and sophisticated socio-environmental models and data capture. The relevance and applicability of these innovations to address threats from pathogens, pests, and weeds in both terrestrial and aquatic ecosystems emphasize the opportunity to build critical mass around interdisciplinary teams at a global scale that can rapidly advance science solutions targeting biosecurity threats.

2.
Sci Total Environ ; 839: 156398, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35654201

RESUMEN

Honey bees (Apis mellifera) are the current model species for pesticide risk assessments, but considering bee diversity, their life histories, and paucity of non-eusocial bee data, this approach could underestimate risk. We assessed whether honey bees were an adequate risk predictor to non-targets. We conducted oral and contact bioassays for Leioproctus paahaumaa, a solitary ground-nesting bee, and A. mellifera, using imidacloprid (neonicotinoid) and dimethoate (organophosphate). The bees responded inconsistently; L. paahaumaa were 36 and 194 times more susceptible to oral and topically applied imidacloprid than A. mellifera, but showed comparable sensitivity to dimethoate. Furthermore, the proposed safety factor of ten applied to honey bee endpoints did not cover the interspecific sensitivity difference. Our standard-setting study highlights the urgent need for more comparative inter-species toxicity studies and the development of standardized toxicity protocols to ensure regulatory pesticide risk assessment frameworks are protective of diverse pollinators.


Asunto(s)
Insecticidas , Plaguicidas , Animales , Abejas , Dimetoato/toxicidad , Insecticidas/toxicidad , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad , Plaguicidas/toxicidad
3.
Environ Entomol ; 50(1): 86-96, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33269804

RESUMEN

Ants represent a highly diverse and ecologically important group of insects found in almost all terrestrial ecosystems. A subset of ant species have been widely transported around the globe and invade many natural ecosystems, often out-competing native counterparts and causing varying impacts on recipient ecosystems. Decisions to control non-native ant populations require an understanding of their interactions and related impacts on native communities. We employed stable isotope analysis and metabarcoding techniques to identify potential dietary niche overlap and identify gut contents of 10 ant species found in natural ecosystems in Aotearoa New Zealand. Additionally, we looked at co-occurrence to identify potential competitive interactions among native and non-native ant species. Ants fed mainly across two trophic levels, with high dietary overlap. Relative to other ant species sampled, two non-native ant species, Linepithema humile and Technomyrmex jocosus, were found to feed at the lowest trophic level. The largest isotopic niche overlap was observed between the native Monomorium antarcticum and the invasive Ochetellus glaber, with analyses revealing a negative co-occurrence pattern. Sequence data of ant gut content identified 51 molecular operational taxonomic units, representing 22 orders and 34 families, and primarily consisting of arthropod DNA. Although we generally found high dietary overlap among species, negative occurrence between a dominant, non-native species and a ubiquitous native species indicates that species-specific interactions could be negatively impacting native ecosystems. Our research progresses and informs the currently limited knowledge around establishing protocols for metabarcoding to investigate ant diet and interactions between native and non-native ant species.


Asunto(s)
Hormigas , Animales , Dieta , Ecosistema , Especies Introducidas , Nueva Zelanda
4.
Insects ; 11(12)2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33348605

RESUMEN

Intraguild predation interactions have substantial theoretical and practical implications for the dynamics of natural competitor populations used for biological control. Intraguild predation on parasitized aphids not only has a direct, negative effect on the parasitoid species, but it may indirectly influence the predator's development, survival, reproduction and predation rates. In this study, we used two-sex life table theory, life table parameters and predation rates of Aphidoletes aphidimyza (Rondani) to compare when its populations fed on aphids (Myzus persicae Sulzer) (Hemiptera: Aphididae) that were either unparasitized or parasitized by Aphidius gifuensis (Ashmead) (Hymenoptera: Braconidae). Our results showed that individuals of A. aphidimyza were capable of completing their development and attaining maturity when they fed on parasitized aphids. Although feeding on parasitized aphids did not influence the survival rates of immature A. aphidimyza, it did significantly slow their development and extended their longevity, thereby reducing the fecundity and predation rates of A. aphidimyza. These findings may be pivotal for better understanding the sustained coexistence of predators with parasitoids in the biological control of aphids.

5.
Insects ; 11(4)2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32326018

RESUMEN

The difficulty to locate mates and overcome predation can hamper species establishment and population maintenance. The effects of sparseness between individuals or the effect of predators on the probability of population growth can be difficult to measure experimentally. For testing hypotheses about population density and predation, we contend that habitat complexity can be simulated using insect mazes of varying mathematical difficulty. To demonstrate the concept, we investigated whether the use of 3D printed mazes of varying complexity could be used to increase spatial separation between sexes of Drosophila simulans, and whether the presence of a generalist predator hampered mate-finding. We then examined how increasing D. simulans population density might overcome the artificially created effects of increasing the distance between mates and having a predator present. As expected, there was an increase in time taken to find a mate and a lower incidence of mating as habitat complexity increased. Increasing the density of flies reduced the searching time and increased mating success, and overcame the effect of the predator in the maze. Printable 3D mazes offer the opportunity to quickly assess the effects of spatial separation on insect population growth in the laboratory, without the need for large enclosed spaces. Mazes could be scaled up for larger insects and can be used for other applications such as learning.

6.
Ecotoxicol Environ Saf ; 183: 109585, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31509930

RESUMEN

The two biological control agents, predatory mite Amblydromalus limonicus Garman & McGregor (Acari: Phytoseiidae) and entomopathogenic fungi (EPF) Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), have the potential to independently suppress the invasive tomato potato psyllid (TPP), Bactericera cockerelli (Sulc), in New Zealand. The integrated strategy of combining the release of predatory mites and EPF may further promote biocontrol of pests. To examine the compatibility of A. limonicus and B. bassiana, we tested the lethal effects of B. bassiana on A. limonicus females on B. cockerelli and calculated the sublethal concentrations of B. bassiana. The effects of sublethal concentrations (LC10 and LC30) of EPF on predatory mite females were assessed on the reproduction parameters of the parental generation (F0). We also evaluated the transgenerational effects of EPF on life table parameters and predation rates of the offspring generation (F1) that was fed on the psyllids. Our results showed that A. limonicus females were susceptible to B. bassiana and the LC50 was 2.2 × 105 conidia mL-1. Sublethal concentrations of EPF (LC30) significantly reduced the fecundity, longevity, oviposition period and predation rates of F0 predatory mite females. However, life table and predation rates of F1 predatory mites were not influenced by sublethal concentrations (LC30), except for the reduction of the preadult and total pre-oviposition period, and the predation rate of F1 males. Also, F1 population parameters including the intrinsic rate of increase (rm), finite rate of increase (λ), gross reproduction rate (GRR), and net reproduction rate (R0) were not significantly influenced by sublethal concentrations (LC10 and LC30). This result suggests that the transgenerational effects of entomopathogenic fungi cannot be carried over to F1. In conclusion, the simultaneous application of both biological control agents does have the potential to control TPP at appropriate intervals during the crop season. Further evaluation in the field will be needed to confirm the viability of this approach to control TPP.


Asunto(s)
Beauveria/fisiología , Hemípteros/microbiología , Ácaros/fisiología , Control Biológico de Vectores/métodos , Solanum lycopersicum/crecimiento & desarrollo , Animales , Beauveria/patogenicidad , Femenino , Fertilidad/fisiología , Longevidad/fisiología , Masculino , Ácaros/microbiología , Nueva Zelanda , Oviposición/efectos de los fármacos , Conducta Predatoria/fisiología , Reproducción/efectos de los fármacos , Estaciones del Año
7.
Ecology ; 100(9): e02749, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31339564

RESUMEN

Worldwide, anthropogenic change is causing biodiversity loss, disrupting many critical ecosystem functions. Most studies investigating the relationship between biodiversity and ecosystem functioning focus on species richness, predominantly within the context of productivity-related functions. Consequently, there is limited understanding of how other biodiversity measures, such as species evenness (the distribution of abundance among species), affect complex multitrophic functions such as pollination. We explore the effect of species evenness on the ecosystem function of pollination using a controlled experiment with selected plants and insects in flight cages. We manipulated the relative abundances of plant and pollinator species, while holding species richness, composition, dominance order, and total abundance constant. Then, we tested how numerical species evenness affected network structure and consequently, seed production, in our artificial communities. Contrary to our expectation, numerical dominance in plant communities increased complementarity in pollinator use (reduced pollinator sharing) among plant species. As predicted by theory, this increased complementarity resulted in higher seed production for the most dominant and rare plant species in our cages. Our results show that in a controlled experimental setting, numerical species evenness can alter important aspects of plant-pollinator networks and plant reproduction, irrespective of species richness, composition, and total abundance. Extending this understanding of how species evenness affects ecosystem functioning to natural systems is crucial as anthropogenic disturbances continue to alter species' abundances, likely disrupting ecosystem functions long before extinctions occur.


Asunto(s)
Ecosistema , Polinización , Biodiversidad , Plantas
8.
Pest Manag Sci ; 75(12): 3200-3209, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30957393

RESUMEN

BACKGROUND: Tomato/potato psyllid (TPP), Bactericera cockerelli (Sulc), is a recently established invasive pest of solanaceous crops in New Zealand. No alternative control strategies are available against TPP due to the development of insecticidal resistance. We investigated the combined use of the predatory mites Amblydromalus limonicus or Neoseiulus cucumeris with either the fungus Beauveria bassiana (suspensions and dry conidia) or with Typha orientalis pollen as a control of TPP in greenhouse bell pepper over 7 weeks. RESULTS: All treatments significantly reduced TPP densities compared with the control. A. limonicus resulted in significantly lower TPP densities than any other combination with N. cucumeris. B. bassiana suspensions did not affect A. limonicus densities when they were combined. However, the application of dry B. bassiana conidia significantly reduced the densities of A. limonicus. The use of T. orientalis pollen resulted in significantly higher densities of A. limonicus but densities of N. cucumeris did not increase. The combined use of A. limonicus with B. bassiana suspensions or T. orientalis pollen resulted in significantly decreased TPP populations and greater crop yield. CONCLUSION: The synergistic application of A. limonicus with B. bassiana suspensions could be a suitable strategy to control TPP in the greenhouse. © 2019 Society of Chemical Industry.


Asunto(s)
Beauveria/fisiología , Hemípteros , Ácaros/fisiología , Control Biológico de Vectores/métodos , Polen/fisiología , Conducta Predatoria/efectos de los fármacos , Alimentación Animal/análisis , Animales , Dieta , Femenino , Typhaceae/fisiología
9.
Annu Rev Entomol ; 64: 51-71, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30256668

RESUMEN

Three species of Vespula have become invasive in Australia, Hawai'i, New Zealand, and North and South America and continue to spread. These social wasp species can achieve high nest densities, and their behavioral plasticity has led to substantial impacts on recipient communities. Ecologically, they affect all trophic levels, restructuring communities and altering resource flows. Economically, their main negative effect is associated with pollination and the apicultural industry. Climate change is likely to exacerbate their impacts in many regions. Introduced Vespula spp. likely experience some degree of enemy release from predators or parasites, although they are exposed to a wide range of microbial pathogens in both their native and introduced range. Toxic baits have been significantly improved over the last decade, enabling effective landscape-level control. Although investigated extensively, no effective biological control agents have yet been found. Emerging technologies such as gene drives are under consideration.


Asunto(s)
Especies Introducidas , Control Biológico de Vectores , Avispas , Animales , Cambio Climático , Conducta Alimentaria , Humanos
10.
Pest Manag Sci ; 75(5): 1317-1327, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30353644

RESUMEN

BACKGROUND: Predator-prey interactions consist of direct consumption of prey by predators and indirect non-consumptive effects on prey. Predator cues can induce predation stress in prey that negatively influences the survival, development, reproduction, and feeding behaviour of the prey. This study evaluated the effects of hemipteran-tending ant (Technomyrmex albipes) odour on the development, survival, reproduction, and predation rates of the predatory mite Amblydromalus limonicus when feeding on an invasive pest of solanaceous crops, Bactericera cockerelli. The age-stage, two-sex life table theory was used to compare the demographic characteristics and predation rates of A. limonicus in the presence and absence of ant odour. RESULTS: We show that exposure to ant odour did not alter the development, survival rate, and fecundity of A. limonicus, but induced a sexually dimorphic response in its longevity; consumption rates also showed that dimorphic response-predation rates increased in female A. limonicus, but not in males. CONCLUSION: To our knowledge, this is the first report indicating increased consumption rates by natural enemies exposed to odour from a mutualist of pest (ant). This finding may provide new insights into understanding tri-partite interaction involving a pest, its predator, and a mutulist of the pest. © 2018 Society of Chemical Industry.


Asunto(s)
Hormigas/metabolismo , Hemípteros , Ácaros/efectos de los fármacos , Odorantes , Conducta Predatoria/efectos de los fármacos , Simbiosis , Animales , Hormigas/fisiología , Longevidad/efectos de los fármacos , Ácaros/fisiología , Reproducción/efectos de los fármacos , Análisis de Supervivencia
11.
Exp Appl Acarol ; 76(1): 109-121, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30194653

RESUMEN

Habitat dispersion, diet and density can influence the per capita population growth of predators, and dispersed habitat can provide a spatial refuge that reduces the possibility of cannibalism among predators, thereby increasing their realized population growth rate. We tested the influence of variable habitat dispersion (dispersed patches, general patches and aggregated patches), two diets (Typha orientalis pollen and Ephestia kuehniella eggs) and initial predator density-one or two Amblydromalus limonicus (Garman and McGregor) (Acari: Phytoseiidae) founder females-on the population growth of A. limonicus in 7 days. Dispersed patches resulted in a higher total number of A. limonicus than the other two types of habitat dispersion from days 3-7 when fed on either of the diets, and started with either one or two A. limonicus females. Compared with E. kuehniella eggs, T. orientalis pollen resulted in more A. limonicus regardless of one or two founder females. Compared with two founder females, beginning with one founder female on pollen produced significantly more predatory mite females in dispersed and aggregated patches. A four-way ANOVA showed that the main effects indicated that habitat, diet, density, and time significantly influenced the number of immature and female A. limonicus. Significant interactions between habitat dispersion and diet were detected on immature and female A. limonicus. Our findings suggest that increasing the dispersion of artificial shelters on crop leaves may stimulate the control efficiency of predators in greenhouses. Furthermore, T. orientalis pollen provides a high nutritional quality supplemental diet that could enhance the ability of A. limonicus to control pests.


Asunto(s)
Ecosistema , Ácaros/fisiología , Control Biológico de Vectores , Conducta Predatoria , Animales , Dieta , Femenino , Control Biológico de Vectores/métodos , Densidad de Población , Crecimiento Demográfico
12.
Proc Biol Sci ; 284(1860)2017 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-28794218

RESUMEN

Two main mechanisms may buffer ecosystem functions despite biodiversity loss. First, multiple species could share similar ecological roles, thus providing functional redundancy. Second, species may respond differently to environmental change (response diversity). However, ecosystem function would be best protected when functionally redundant species also show response diversity. This linkage has not been studied directly, so we investigated whether native and exotic pollinator species with similar traits (functional redundancy) differed in abundance (response diversity) across an agricultural intensification gradient. Exotic pollinator species contributed most positive responses, which partially stabilized overall abundance of the pollinator community. However, although some functionally redundant species exhibited response diversity, this was not consistent across functional groups and aggregate abundances within each functional group were rarely stabilized. This shows functional redundancy and response diversity do not always operate in concert. Hence, despite exotic species becoming increasingly dominant in human-modified systems, they cannot replace the functional composition of native species.


Asunto(s)
Biodiversidad , Ecosistema , Insectos , Especies Introducidas , Agricultura , Animales , Nueva Zelanda , Polinización
13.
Biol Rev Camb Philos Soc ; 92(3): 1769-1784, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27807946

RESUMEN

Sensory-based conservation harnesses species' natural communication and signalling behaviours to mitigate threats to wild populations. To evaluate this emerging field, we assess how sensory-based manipulations, sensory mode, and target taxa affect success. To facilitate broader, cross-species application of successful techniques, we test which behavioural and life-history traits correlate with positive conservation outcomes. We focus on seabirds, one of the world's most rapidly declining groups, whose philopatry, activity patterns, foraging, mate choice, and parental care behaviours all involve reliance on, and therefore strong selection for, sophisticated sensory physiology and accurate assessment of intra- and inter-species signals and cues in several sensory modes. We review the use of auditory, olfactory, and visual methods, especially for attracting seabirds to newly restored habitat or deterring birds from fishing boats and equipment. We found that more sensory-based conservation has been attempted with Procellariiformes (tube-nosed seabirds) and Charadriiformes (e.g. terns and gulls) than other orders, and that successful outcomes are more likely for Procellariiformes. Evolutionary and behavioural traits are likely to facilitate sensory-based techniques, such as social attraction to suitable habitat, across seabird species. More broadly, successful application of sensory-based conservation to other at-risk animal groups is likely to be associated with these behavioural and life-history traits: coloniality, philopatry, nocturnal, migratory, long-distance foraging, parental care, and pair bonds/monogamy.


Asunto(s)
Comunicación Animal , Conducta Animal , Aves/fisiología , Conservación de los Recursos Naturales , Animales , Ecosistema
14.
PeerJ ; 4: e2779, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28028464

RESUMEN

BACKGROUND: Functional traits are the primary biotic component driving organism influence on ecosystem functions; in consequence, traits are widely used in ecological research. However, most animal trait-based studies use easy-to-measure characteristics of species that are at best only weakly associated with functions. Animal-mediated pollination is a key ecosystem function and is likely to be influenced by pollinator traits, but to date no one has identified functional traits that are simple to measure and have good predictive power. METHODS: Here, we show that a simple, easy to measure trait (hairiness) can predict pollinator effectiveness with high accuracy. We used a novel image analysis method to calculate entropy values for insect body surfaces as a measure of hairiness. We evaluated the power of our method for predicting pollinator effectiveness by regressing pollinator hairiness (entropy) against single visit pollen deposition (SVD) and pollen loads on insects. We used linear models and AICC model selection to determine which body regions were the best predictors of SVD and pollen load. RESULTS: We found that hairiness can be used as a robust proxy of SVD. The best models for predicting SVD for the flower species Brassica rapa and Actinidia deliciosa were hairiness on the face and thorax as predictors (R2 = 0.98 and 0.91 respectively). The best model for predicting pollen load for B. rapa was hairiness on the face (R2 = 0.81). DISCUSSION: We suggest that the match between pollinator body region hairiness and plant reproductive structure morphology is a powerful predictor of pollinator effectiveness. We show that pollinator hairiness is strongly linked to pollination-an important ecosystem function, and provide a rigorous and time-efficient method for measuring hairiness. Identifying and accurately measuring key traits that drive ecosystem processes is critical as global change increasingly alters ecological communities, and subsequently, ecosystem functions worldwide.

15.
J Chem Ecol ; 41(11): 1018-27, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26432279

RESUMEN

Vespula wasps are widely distributed invasive alien species that are able to reach high population densities in the 1.2 M ha of beech forests (Fuscospora spp.) of New Zealand's South Island. These endemic temperate forests have an abundance of carbohydrate-rich honeydew produced by native scale insects (Ultracoelostoma spp.). A characteristic aroma is associated with the honeydew in beech forests, which we hypothesized is the signal used by wasps to harvest the vast resources previously exploited by birds and other insects. Volatile collections were taken of black beech tree trunks with honeydew and sooty mold present, and analyzed with a gas chromatograph-mass spectrometer. Eleven compounds (benzaldehyde, benzyl alcohol, 2-phenylethyl acetate, 2-phenylethanol, phenylacetaldehyde, methyl 2-phenylacetate, ethyl 2-phenylacetate, methyl salicylate, n-octanol, octan-3-ol, and 1-octen-3-ol) were positively identified from the headspace, and were shown to elicit an electrophysiological response from Vespula vulgaris worker antennae by using electroantennography (EAG). Field trials with delta traps individually baited with these compounds confirmed wasp attraction to 8 of the 11 compounds tested, with 2-phenylethyl acetate, methyl salicylate, and octan-3-ol capturing the same numbers of wasps as the control. In later trials, attraction to a 1:1 blend of benzaldehyde and n-octanol was significantly higher (45%) than to any other treatment. Many of the chemicals identified are known to be associated with fermenting sugars, or with fungal aroma. Benzaldehyde and n-octanol are common compounds produced by many different species in nature. The ability to respond to generic signals emanating from sugar resources is likely to contribute to the success of V. vulgaris as an invasive species.


Asunto(s)
Cadena Alimentaria , Hemípteros/fisiología , Especies Introducidas , Compuestos Orgánicos Volátiles/metabolismo , Avispas/fisiología , Animales , Nueva Zelanda , Odorantes
16.
Proc Natl Acad Sci U S A ; 112(20): E2648-57, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25941361

RESUMEN

Food availability is a primary driver of avian population regulation. However, few studies have considered the effects of what is essentially a massive supplementary feeding experiment: the practice of wild bird feeding. Bird feeding has been posited as an important factor influencing the structure of bird communities, especially in urban areas, although experimental evidence to support this is almost entirely lacking. We carried out an 18-mo experimental feeding study at 23 residential properties to investigate the effects of bird feeding on local urban avian assemblages. Our feeding regime was based on predominant urban feeding practices in our region. We used monthly bird surveys to compare avian community composition, species richness, and the densities of local species at feeding and nonfeeding properties. Avian community structure diverged at feeding properties and five of the commonest garden bird species were affected by the experimental feeding regime. Introduced birds particularly benefitted, with dramatic increases observed in the abundances of house sparrow (Passer domesticus) and spotted dove (Streptopelia chinensis) in particular. We also found evidence of a negative effect on the abundance of a native insectivore, the grey warbler (Gerygone igata). Almost all of the observed changes did not persist once feeding had ceased. Our study directly demonstrates that the human pastime of bird feeding substantially contributes to the structure of avian community in urban areas, potentially altering the balance between native and introduced species.


Asunto(s)
Biota , Aves/fisiología , Ciudades , Métodos de Alimentación/veterinaria , Análisis de Varianza , Animales , Humanos , Especies Introducidas , Nueva Zelanda , Densidad de Población
17.
Environ Entomol ; 43(6): 1514-25, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25368982

RESUMEN

Honeydew is abundant in many ecosystems and may provide an alternative food source (a buffer) for pollinators during periods of food shortage, but the impact of honeydew on pollination systems has received little attention to date. In New Zealand, kanuka trees (Myrtaceae: Kunzea ericoides (A. Rich) Joy Thompson) are often heavily infested by the endemic honeydew-producing scale insect Coelostomidia wairoensis (Maskell) (Hemiptera: Coelostomidiidae) and the period of high honeydew production can overlap with kanuka flowering. In this study, we quantified the sugar resources (honeydew and nectar) available on kanuka and recorded nocturnal insect activity on infested and uninfested kanuka during the flowering period. Insects were abundant on infested trees, but flowers on infested trees received fewer insect visitors than flowers on uninfested trees. There was little evidence that insects had switched directly from nectar-feeding to honeydew-feeding, but it is possible that some omnivores (e.g., cockroaches) were distracted by the other honeydew-associated resources on infested branches (e.g., sooty molds, prey). Additional sampling was carried out after kanuka flowering had finished to determine honeydew usage in the absence of adjacent nectar resources. Moths, which had fed almost exclusively on nectar earlier, were recorded feeding extensively on honeydew after flowering had ceased; hence, honeydew may provide an additional food source for potential pollinators. Our results show that honeydew resources can impact floral visitation patterns and suggest that future pollinator studies should consider the full range of sugar resources present in the study environment.


Asunto(s)
Carbohidratos/análisis , Heces/química , Conducta Alimentaria/fisiología , Hemípteros/química , Insectos/fisiología , Kunzea/química , Néctar de las Plantas/química , Animales , Hemípteros/fisiología , Interacciones Huésped-Parásitos/fisiología , Kunzea/parasitología , Nueva Zelanda , Polinización/fisiología
18.
PLoS One ; 8(7): e70316, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23922978

RESUMEN

Sooty mould fungi are ubiquitous, abundant consumers of insect-honeydew that have been little-studied. They form a complex of unrelated fungi that coexist and compete for honeydew, which is a chemically complex resource. In this study, we used scanning electron microscopy in combination with T-RFLP community profiling and ITS-based tag-pyrosequencing to extensively describe the sooty mould community associated with the honeydews of two ecologically important New Zealand coelostomidiid scale insects, Coelostomidia wairoensis and Ultracoelostoma brittini. We tested the influence of host plant on the community composition of associated sooty moulds, and undertook limited analyses to examine the influence of scale insect species and geographic location. We report here a previously unknown degree of fungal diversity present in this complex, with pyrosequencing detecting on average 243 operational taxonomic units across the different sooty mould samples. In contrast, T-RFLP detected only a total of 24 different "species" (unique peaks). Nevertheless, both techniques identified similar patterns of diversity suggesting that either method is appropriate for community profiling. The composition of the microbial community associated with individual scale insect species varied although the differences may in part reflect variation in host preference and site. Scanning electron microscopy visualised an intertwined mass of fungal hyphae and fruiting bodies in near-intact physical condition, but was unable to distinguish between the different fungal communities on a morphological level, highlighting the need for molecular research. The substantial diversity revealed for the first time by pyrosequencing and our inability to identify two-thirds of the diversity to further than the fungal division highlights the significant gap in our knowledge of these fungal groups. This study provides a first extensive look at the community diversity of the fungal community closely associated with the keystone insect-honeydew systems of New Zealand's native forests and suggests there is much to learn about sooty mould communities.


Asunto(s)
Hongos/aislamiento & purificación , Hemípteros/microbiología , Animales , Biodiversidad , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , Hongos/clasificación , Hongos/genética , Hemípteros/fisiología , Nueva Zelanda , Árboles/microbiología
19.
FEMS Microbiol Ecol ; 81(3): 537-46, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22468989

RESUMEN

Scale insects are important ecologically and as agricultural pests. The majority of scale insect taxa feed exclusively on plant phloem sap, which is carbon rich but deficient in essential amino acids. This suggests that, as seen in the related aphids and psyllids, scale insect nutrition might also depend upon bacterial symbionts, yet very little is known about scale insect-bacteria symbioses. We report here the first identification and molecular characterization of symbiotic bacteria associated with the New Zealand giant scale Coelostomidia wairoensis, using fluorescence in situ hybridization (FISH), transmission electron microscopy (TEM) and 16S rRNA gene-based analysis. Dissection and FISH confirmed the location of the bacteria in large, paired, multilobate organs in the abdominal region of the insect. TEM indicated that the dominant pleomorphic bacteria were confined to bacteriocytes in the sheath-enclosed bacteriome. Phylogenetic analysis revealed the presence of three distinct bacterial types, the bacteriome-associated B-symbiont (Bacteroidetes), an Erwinia-related symbiont (Gammaproteobacteria) and Wolbachia sp. (Alphaproteobacteria). This study extends the current knowledge of scale insect symbionts and is the first microbiological investigation of the ecologically important coelostomidiid scales.


Asunto(s)
Bacteroidetes/aislamiento & purificación , Gammaproteobacteria/aislamiento & purificación , Hemípteros/microbiología , Wolbachia/aislamiento & purificación , Animales , Bacteroidetes/clasificación , Bacteroidetes/genética , Bacteroidetes/fisiología , Femenino , Gammaproteobacteria/clasificación , Gammaproteobacteria/genética , Gammaproteobacteria/fisiología , Hemípteros/fisiología , Hibridación Fluorescente in Situ , Nueva Zelanda , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Simbiosis , Wolbachia/clasificación , Wolbachia/genética , Wolbachia/fisiología
20.
J Chem Ecol ; 37(11): 1231-41, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22089823

RESUMEN

The quantity and chemical composition of honeydew produced by scale insects may influence wider community structure, but little is known about the detailed chemical composition of the honeydew found in forest ecosystems. We used gas chromatography-mass spectrometry to examine the amino acid and carbohydrate composition of honeydew from three New Zealand communities. Low molecular weight carbohydrates (mono-, di-, and tri-saccharides) were derivatized using a modified trimethylsilyl (TMS) method, and amino and non-amino organic acids were derivatized using methylchloroformate (MCF). These recently developed derivatization methods allowed us to detect atypical compounds such as sugar alcohols, fatty acids, and non-amino organic acids, in addition to the more routinely studied compounds such as sugars and amino acids. Some compounds could not be identified and may be novel. Multivariate analysis showed that honeydew from each scale insect species had a distinctive amino acid and carbohydrate signature. We suggest these chemical signatures may influence the types of consumers that are attracted to different honeydews and may explain the characteristic communities associated with these honeydews.


Asunto(s)
Biopolímeros/análisis , Biopolímeros/metabolismo , Hemípteros/química , Hemípteros/metabolismo , Animales , Biopolímeros/química , Cromatografía de Gases y Espectrometría de Masas , Peso Molecular , Especificidad de la Especie , Árboles
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