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2. Alternative foods for the multicoloured Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Berkvens, Nick, Landuyt, Carmen, Deforce, Koen, Berkvens, Dirk, Tirry, Luc, and de Clercq, Patrick
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellidae, Harmonia axyridis, invasive species, development, frugivory, fungivory, pollinivory, and reproduction
- Language:
- English
- Description:
- The multicoloured Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae) may potentially exploit a range of "alternative" food sources. The nutritional value of three common non-prey food groups, i.e. fruit, fungi and pollen, is examined in this study. Development, reproduction and survival of the species were assessed in the laboratory on diets of apple, pear and raspberries and the fungi Oidium lycopersicum, Botrytis cinerea, Sclerotinia sclerotiorum and Rhizoctonia solani. When fed exclusively on these foods this ladybird failed to complete its development or reproduce. However, larval and adult survival was prolonged by 4 to 8 days and 55 to 67 days, respectively, when fruit was offered compared with only water. During a field study H. axyridis adults were collected monthly from March to October at two locations near Ghent, Belgium. Gut analysis demonstrated that, despite the continued presence of aphids, over 90% of all the adults collected contained pollen throughout the year. The pollen belonged to 53 different pollen types. Monthly average numbers of pollen grains in the gut varied from 5 to 233 grains. In contrast, there were about 35,000 grains in the guts of H. axyridis females that successfully developed and reproduced in the laboratory on diet that consisted of only pollen. This suggests that in the field in the majority of cases pollinivory mainly only provided complementary nutrients for this coccinellid. The use of alternative non-prey foods like pollen and fruit may play a role in sustaining populations of this coccinellid at times when the optimal prey is absent.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Aproceros leucopoda (Hymenoptera: Argidae): An East Asian pest of elms (Ulmus spp.) invading Europe
- Creator:
- Blank, Stephan M., Hara, Hideho, Mikulás, József, Csóka, György, Ciornei, Constantin, Constantineanu, Raoul, Constantineanu, Irinel, Roller, Ladislav , Altenhofer, Ewald, Huflejt, Tomasz, and Vétek, Gábor
- Type:
- article, model:article, and TEXT
- Subject:
- Argidae, Aproceros leucopoda, sawfly, Ulmus, Europe, invasive species, pest species, identification, bionomy, dispersal, and Dutch elm disease
- Language:
- English
- Description:
- An invasive sawfly Aproceros leucopoda Takeuchi, 1939, which originates from East Asia, has colonized elms (Ulmus spp.) in Austria, Hungary, Poland, Romania, Slovakia and the Ukraine, at least since 2003. In Europe, the larvae can completely defoliate native and non-native elm trees and may cause at least partial dieback. Field observations indicate that elms are infested independent of their age and site characteristics. The life cycle of A. leucopoda is described based on material reared in Hokkaido, Japan. Parthenogenetic reproduction, short life cycle of summer generations and the ability to produce four generations per year result in the production of numerous progeny. The evolution of a seasonal dimorphism in head morphology, a simple cocoon that is attached directly to the host plant and a short period spent in the cocoon stage during summer, are putative apomorphies shared by Aproceros Takeuchi, 1939 and Aprosthema Konow, 1899. These traits reduce developmental costs and contribute to the proliferation of A. leucopoda. No specialized parasitoid, that can effectively reduce outbreaks of this species, is known. It is likely that this pest will spread into central and south-western Europe. Further monitoring of A. leucopoda is required to assess future range extensions in Europe, its exacerbating effect on Dutch elm disease and to find a suitable biocontrol agent. Concise keys to imaginal and larval stages are presented that will facilitate the identification of A. leucopoda.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Assessement of possible diel and sex-related differences in round goby (Neogobius melanostomus) diet
- Creator:
- Všetičková, Lucie, Janáč, Michal, Roche, Kevin, and Jurajda, Pavel
- Type:
- article, model:article, and TEXT
- Subject:
- invasive species, diel feeding, inter-sex differences, nest-guarding, and breeding season
- Language:
- English
- Description:
- Several aspects of invasive round goby (Neogobius melanostomus) biology are based on sporadic observations or anecdotal reports only, e.g. they are night feeders, they prey on eggs and larvae of native fish and male feeding ceases or is highly restricted during breeding due to nest-guarding. To test the general validity of such hypotheses, we assessed diel and inter-sex differences in diet and feeding intensity of 232 gobies (144 female [54 day:90 night] and 88 male [39 day:49 night]) caught during the breeding season. Gobies took primarily aquatic insect larvae and did not predate on eggs, larvae or juveniles of native fish. Unlike previous studies, we observed no diel difference in feeding intensity or diet composition; hence no universal diel pattern can be implied for round goby feeding. On the other hand, we observed significant inter-sex differences in both feeding intensity and diet composition, with males consuming less food than females, presumably due to restricted feeding activity during nest-guarding. Inter-sex shifts in both diet composition and amount of food were less than expected, however, suggesting that, under most conditions, there is no reason to expect a fatal decrease in male energy intake, as suggested by some earlier studies.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Chamois introductions to Central Europe and New Zealand
- Creator:
- Martínková, Natália, Zemanová, Barbora, Kranz, Andreas, Giménez, Mabel D., and Hájková, Petra
- Type:
- article, model:article, and TEXT
- Subject:
- Alpine chamois, animal translocations, introduction, invasive species, and Rupicapra rupicapra
- Language:
- English
- Description:
- Chamois (Rupicapra rupicapra) introductions were popular at the beginning of the 20th century when first animals were shipped from Austria to the Czech Republic and New Zealand. The historical record of the Czech introduction indicates Neuberg Mürzsteg Game Reserve in Eastern Alps, Styria, Austria as the main area of origin of founders. First animals for the New Zealand population are thought to have originated from Ebensee, Upper Austria, Austria and later more animals came from the Mürzsteg region. We sequenced mitochondrial control region of chamois from the introduced populations and their putative source areas, and we applied median-joining networks and Bayesian inference analysis to distinguish the regions of origin of female founders. We found the Mürzsteg region as the most likely source population for introductions to the Czech Republic and New Zealand, supplemented with close association with sequences from Ebensee in populations from the Czech Republic. Genetic diversity present in the Czech Republic was further relocated to the introduced populations in Slovakia in the 1960’s.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Diapause and post-diapause quiescence demonstrated in overwintering Harmonia axyridis (Coleoptera: Coccinellidae) in northwestern Europe
- Creator:
- Raak-Van Den Berg, C. Lidwien, Peter Willem De Jong, Hemerik, Lia, and Van Lenteren, Joop C.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, invasive species, hibernation, diapause, quiescence, pre-oviposition period, semi-field esperiment, 2, and 59
- Language:
- English
- Description:
- The Asian ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is regarded as an invasive species in many parts of the world. In a previous study we hypothesised that H. axyridis enters diapause at the end of October and then shifts to a quiescent state in December in northwestern Europe. In the present study we test this idea of a short, early period of diapause by sampling beetles from their hibernation sites immediately after their migratory flights in October, subsequently keeping them in outdoor cages, and then, after certain time-intervals, measuring the pre-oviposition time under optimal egg-laying laboratory conditions at 25°C. We did this at both short (12L) and long (16L) photoperiods, since a photoperiodic response is an indicator of true diapause, rather than quiescence. A significant, albeit small, difference in pre-oviposition period between the two photoperiods, which disappears in December, corroborates our earlier hypothesis that the ladybirds are in a state of diapause until mid-December. Compared with that of native ladybirds the diapause of H. axyridis generally is relatively short and weak; moreover, it appears to have become shorter over the last decade. This flexibility in diapausing behaviour may be an important factor that contributes to the invasive success of H. axyridis., C. Lidwien Raak-Van Den Berg ... [et al.]., and Obsahuje seynam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Diet of the American mink Neovison vison in an agricultural landscape in western Poland
- Creator:
- Keawczyk, Agata J., Bogdziewicz, Michał, and Czyz, Michał J.
- Type:
- article, model:article, and TEXT
- Subject:
- invasive species, feeding ecology, farmland, predation, and Mustelidae
- Language:
- English
- Description:
- We studied the diet of the American mink (Neovison vison) in small artificial watercourses located in a farmland area of the valley of the River Barycz in Poland. Rodents, mainly Microtus spp., were the most frequent prey identified, occurring in 88.3 % of all analyzed mink scat. Minks also fed willingly on fish, birds and amphibians, whereas insects, crayfish and reptiles accounted for only a small part of the biomass of food consumed. The food niche breadth of the mink’s diet was wide, and varied significantly between seasons; in spring and autumn minks preyed mainly on rodents and fish, while the winter and summer diets consisted of a broad characterization of prey items. The proportion of mammals in the diet also decreased significantly during the summer months. These patterns differ from those previously reported in Europe, and demonstrate the plasticity of the mink diet across habitats.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Distribution and dispersal of the invasive Asian chestnut gall wasp, Dryocosmus kuriphilus (Hymenoptera: Cynipidae), across the heterogeneous landscape of the Iberian Peninsula
- Creator:
- Gil-Tapetado, Diego, Gómez, José F, Cabrero-Sañudo, Francisco J, and Nieves-Aldrey, José L
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, Hymenoptera, Pyrenejský poloostrov, Iberian Peninsula, Cynipidae, Dryocosmus kuriphilus, Asian chestnut gall wasp, invasive species, niche models, dispersal, distribution, 2, and 59
- Language:
- English
- Description:
- Dryocosmus kuriphilus (Hymenoptera: Cynipidae), also known as the Asian chestnut gall wasp, is a non-native invasive species that has recently appeared in many regions of Europe, including the Iberian Peninsula. This species is an important pest of chestnut trees in several regions and is of concern for foresters in these areas. The results of this research revealed 14 different hotspots of infestation of D. kuriphilus and resulted in the development of models that predict the distribution of D. kuriphilus in Spain over the next 37 years (2019-2055). These results indicate a rapid spread in all Spanish chestnut forests and identify areas that are theoretically highly suitable and susceptible to colonization by this cynipid based on predictions of three different niche models. Although D. kuriphilus is able to induce galls on all chestnut trees, the models indicate that there are differences in the suitability of the different regions for this species. This differential suitability results in some areas having better environmental conditions than others for D. kuriphilus, which is a factor that should be taken into account in its management and biological control. This study of the current distribution, patterns of dispersal using GIS and potentially suitable areas for D. kuriphilus, using niche models will assist in the management and control of this pest in Spain., Diego Gil-Tapetado, José F. Gómez, Francisco J. Cabrero-Sañudo, José L. Nieves-Aldrey., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Effects of larval diet on female reproductive output of the European coccinellid Adalia bipunctata and the invasive species Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Ware, Remy L., Yguel, Benjamin, and Majerus, Michael E.N.
- Type:
- article, model:article, and TEXT
- Subject:
- Adalia bipunctata, aphidophagous guilds, cannibalism, Coccinellidae, Harmonia axyridis, intraguild predation, invasive species, larval diet, oviposition, ovariole number, reproductive fitness, and resource competition
- Language:
- English
- Description:
- Cannibalism and intraguild predation (IGP) are both common phenomena amongst aphidophagous coccinellids and serve as vital alternative feeding strategies which can prolong survival during periods of aphid scarcity. A reduction in essential prey density and the acceptance of conspecific or heterospecific prey are likely to have a considerable influence on both larval development and adult reproduction. However, little is known about the legacy of larval diet on adult performance. This paper considers the effects of the diet provided to larvae of Harmonia axyridis (Pallas) and Adalia bipunctata (Linnaeus) (Coleoptera: Coccinellidae) on the reproductive output of the resulting females. Results showed that larval diets, including treatments analogous to competition and IGP, did not affect adult longevity, ovipositional lag, proportion of eggs laid in clutches or ovariole number in H. axyridis or A. bipunctata. However, some variation in the maximum clutch size and oviposition rate was seen. A larval diet of unlimited aphids resulted in the largest clutches of eggs being laid by both species. The total number of eggs laid over 30 days was largest for H. axyridis when larvae were reared on unlimited aphids or limited aphids supplemented with either conspecific or heterospecific eggs, whereas oviposition was lower for A. bipunctata females that had received conspecific or heterospecific eggs in their larval diets. The results have also enabled us to make some general comparisons of reproductive parameters between the two species, and to refute the hypothesis that the maximum clutch size laid by a female ladybird is limited by the number of ovarioles within an ovary. We conclude that IGP of A. bipunctata eggs by H. axyridis larvae has a positive effect on reproductive output and is therefore likely to further contribute to the spread and increase of H. axyridis in Britain.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Effects of salinity on temperature-dependent photosynthetic parameters of a native C3 and a non-native C4 marsh grass in the Yangtze Estuary, China
- Creator:
- Ge, Z.-M., Zhang, L.-Q., Yuan, L., and Zhang, C.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, Čína, China, carboxylation efficiency, coastal wetlands, gas exchange, invasive species, marsh grass, Yangtze Estuary, 2, and 581
- Language:
- Multiple languages
- Description:
- The invasion of Spartina alterniflora along the coasts of China has allowed this C4 grass to outcompete often much of the native, salt marsh vegetation, such as Phragmites australis (C3 grass), in the Yangtze Estuary. In this study, native grass, P. australis, and non-native grass, S. alterniflora, were grown in fresh and saline water (moderate salinity of 15‰ and high salinity of 30‰) to compare the effects of salinity on photosynthetic and biochemical parameters in combination with measurement temperatures. The C4 grass, S. alterniflora, showed a greater CO2 assimilation rate than P. australis, across the tested temperatures. The net photosynthetic rate declined significantly with increasing salinity as a result of inhibited stomatal conductance together with a greater decrease in the maximum rate of electron transport (Jmax). In P. australis, salt treatments shifted the optimum temperatures for the maximum rate of carboxylation by Rubisco (Vcmax) and J max to lower temperatures. S. alterniflora showed a greater salt tolerance to moderate stress than that of the native grass, with lower sensitivity of V cmax, Jmax, and the maximum rate of phosphoenolpyruvate carboxylation. Both moderate and high stress decreased significantly stomatal conductance of S. alterniflora; high salinity reduced significantly photosynthetic efficiency and Jmax. Our findings indicated that the combination of stomatal conductance, enzyme activity, and electron transport affected the photosynthetic performance of the plants in response to salt treatments. The success of S. alterniflora could be probably attributed to its C4 photosynthetic pathway and the tolerance to moderate salinity. In this study, a modified parameterization of the photosynthetic model was suggested to support a more reasonable simulation of photosynthesis under salt stress., Z.-M. Ge, L.-Q. Zhang, L. Yuan, C. Zhang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
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