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22. Intraguild predation between the aphidophagous ladybird beetles Harmonia axyridis and Coccinella undecimpunctata (Coleoptera: Coccinellidae): the role of body weight
- Creator:
- Félix, Sandra and Soares, António Onofre
- Type:
- article, model:article, and TEXT
- Subject:
- Harmonia axyridis, Coccinella undecimpunctata, intraguild predation (IGP), asymmetrical IGP mobility, and body-weight
- Language:
- English
- Description:
- The magnitude, direction and symmetry of intraguild predation (IGP) between the developmental stages of the aphidophagous Harmonia axyridis Pallas and Coccinella undecimpunctata L. were characterized and compared. Mobility and body weight were the main factors affecting the magnitude of IGP. H. axyridis was more often the predator than C. undecimpunctata and eggs the most vulnerable developmental stage. There was significant asymmetrical IGP on eggs by the second and later, and fourth larval stages of H. axyridis and C. undecimpunctata, respectively. Asymmetrical IGP of pupae was only recorded for the fourth larval stage of H. axyridis. There was no IGP between adults, but larvae of both species attacked heterospecifics. The best model of the relationship between rate of predation and the difference in the body weight of IG predator and prey differs for the two ladybirds. A small difference in the body weights leads to a marked increase in the rate of predation in H. axyridis but not in C. undecimpunctata. In asymmetrical combinations, increase in body weight of the intraguild predator did not significantly increase the rate of predation. Mobility and body weight were not the only important parameters involved in the symmetry of IGP. Aggressive behaviour of H. axyridis negatively affected the survival of C. undecimpunctata.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
23. Key life stages of two predatory ladybird species (Coleoptera: Coccinellidae)
- Creator:
- Kindlmann, Pavel, Yasuda, Hironori, Sato, Satoru, and Shinya, Katsuhiro
- Type:
- article, model:article, and TEXT
- Subject:
- key factor analysis, survival level, larvae, Harmonia axyridis, Coccinella septempunctata, Coccinellidae, and ladybirds
- Language:
- English
- Description:
- Development and survival of larvae of two predatory ladybird species, Harmonia axyridis (Pallas) and Coccinella septempunctata L. on hibiscus (Hibiscus syridis L.) trees was followed daily outdoors during four seasons. Data were analysed and stage-specific mortality in a stage-structured model was estimated using Manly's (1997) method. Subsequently, key factor analysis was used to determine the life stages in which the daily mortality was best correlated with the total mortality during larval life. Consistently with the results from the first two years, the larvae suffered the greatest mortality during the first and fourth instars. The k-values for these two instars were also best correlated with those for the whole larval life, especially in H. axyridis.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
24. Laboratory studies on intraguild predation and cannibalism among coccinellid larvae (Coleoptera: Coccinellidae)
- Creator:
- Rondoni, Gabriele, Onofri, Andrea, and Ricci, Carlo
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coccinellidae, Harmonia axyridis, intraguild predation, biological control, invasive species, Italy, interval-censored survival analysis, 2, and 59
- Language:
- English
- Description:
- 1_Intraguild predation (IGP) and cannibalism occur in the field and could affect the dominance structure of guilds of coccinellid species. The exotic biological control agent Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is now well established in most areas of Northern and Central Italy, but it is unclear what effect this species could have on native dominant and non-dominant coccinellids with which it co-occurs. In order to predict the trophic interactions in coccinellid guilds and the likely effect of H. axyridis, the incidence of IGP and cannibalism among the following six species were evaluated under laboratory conditions: H. axyridis, three native dominant species, Adalia bipunctata (L.), Oenopia conglobata (L.) and Coccinella septempunctata L. and two native non-dominant species, Platynaspis luteorubra (Goeze) and Scymnus apetzi (Mulsant). Unfed and fed fourth instar larvae of the above species were paired in an experimental arena and the incidence of predation recorded over a period of 24 h. In absence of aphids, the survival probabilities (SP) of A. bipunctata and O. conglobata were lowest when paired with either C. septempunctata or H. axyridis (< 0.20 SP after 24 h). The SP of C. septempunctata was similar if paired with either a conspecific larva or H. axyridis (< 0.34 SP after 24 h) and that of H. axyridis was reduced similarly if paired with either a conspecific larva or C. septempunctata (> 0.71 SP after 24 h). The SP of P. luteorubra was lower when paired with A. bipunctata and C. septempunctata (< 0.07 SP after 24 h) than with other species and that of S. apetzi was greatly reduced when paired with all the dominant and exotic species (< 0.27 SP after 24h)., 2_In presence of aphids no predatory events occurred in most combinations. H. axyridis acted as a strong predator of native dominant and non-dominant coccinellids when the aphids are scarce. We did not find any evidence, however, that the incidence of IGP among exotic and native species is higher than either IGP or cannibalism in native species. The likelihood of IGP occurring in the field is discussed., Gabriele Rondoni, Andrea Onofri, Carlo Ricci., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25. Leucopis annulipes larvae (Diptera: Chamaemyiidae) use a furtive predation strategy within aphid colonies
- Creator:
- Fréchette, Bruno, Larouche, Francois , and Lucas, Éric
- Type:
- article, model:article, and TEXT
- Subject:
- Predation strategy, active-searching predator, furtive predator, Chamaemyiidae, Leucopis annulipes, Cecidomyiidae, Aphidoletes aphidimyza, Coccinellidae, Harmonia axyridis, and Acyrthosiphon pisum
- Language:
- English
- Description:
- A laboratory experiment was conducted to determine whether the predation strategy of larvae of the aphidophagous silver fly Leucopis annulipes Zetterstedt (Diptera: Chamaemyiidae) is furtive, as are larvae of the aphidophagous midge Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae), or active like aphidophagous ladybird beetle larvae (Coleoptera: Coccinellidae). The impact of L. annulipes larvae on pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), colony disturbance was evaluated and compared with that of the furtive predator A. aphidimyza and the active-searching ladybird beetle Harmonia axyridis Pallas. Results indicate that aphids showed significantly fewer defensive acts (dropping, walking away, wriggling) in the presence of L. annulipes larvae than of ladybird beetle larvae. Furthermore, the impact of L. annulipes larvae on aphid colony disturbance was similar to that of A. aphidimyza and to a control treatment without predators. These results clearly indicate that L. annulipes larvae use a furtive predation strategy.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
26. Life history of Adalia bipunctata (Coleoptera: Coccinellidae) in Japan
- Creator:
- Sakuratani, Yasuyuki, Matsumoto, Yoshihito, Oka, Motoki, Kubo, Takahiko, Fujii, Atsushi, Uotani, Minatsu, and Teraguchi, Toru
- Type:
- article, model:article, and TEXT
- Subject:
- Adalia bipunctata, Harmonia axyridis, ladybird, univoltine, life history, immigrant, intraguild predation, and Japan
- Language:
- English
- Description:
- Adalia bipunctata is a well-known predaceous ladybird distributed in Europe, Central Asia and North America. This species has not been recorded in Japan. Recently, we found this species in the Osaka Bay area in central Japan, and assume that it was imported with goods such as timber by ships. We studied the life history and the distribution in the Osaka Bay area since the initial discovery. The larvae and adults preyed on aphids (mainly, Periphyllus viridis) on trees such as Acer buergerianum and Rhaphiolepis umbellata. The over-wintered adults appeared in March and laid eggs. The adults emerged in spring, and were in the rolled leaves throughout the rest of the year. Thus, in Japan this ladybird is univoltine with long inactivity in adult. The life history of Japanese population of A. bipunctata differs considerably from other areas where populations are multivoltine. The developmental threshold was estimated to be 6.3°C and the sum of effective temperatures was 322.6 day-degrees for the period from egg to adult emergence. Predation on prepupae of A. bipunctata by the larvae of native species such as Harmonia axyridis was observed occasionally.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27. Molecular analysis of the gut contents of Harmonia axyridis (Coleoptera: Coccinellidae) as a method for detecting intra-guild predation by this species on aphidophagous predators other than coccinellids
- Creator:
- Ingels, Brecht, Aebi, Alexandre, Hautier, Louis, Van Leeuwen, Thomas, and De Cercq, Patrick
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, Neuroptera, Chrysopidae, Chrysoperla carnea, Diptera, Syrphidae, Episyrphus balteatus, intraguild predation, gut-content analysis, 2, and 59
- Language:
- English
- Description:
- Several studies have demonstrated that the invasive ladybird Harmonia axyridis is a strong intra-guild predator of native species of ladybird. Laboratory studies have shown that H. axyridis can be an intra-guild predator of aphid predators other than coccinellids, including the hoverfly Episyrphus balteatus and lacewing Chrysoperla carnea. However, little is known about the effect of intra-guild predation (IGP) by H. axyridis on hoverfly and lacewing populations in the field. In the present study molecular analyses were used to detect the DNA of E. balteatus and C. carnea in the gut contents of H. axyridis. Primers for the syrphid and chrysopid prey were designed and feeding experiments performed to determine how long prey DNA remains detectable in the guts of this ladybird. DNA detection was influenced by the life stage of the predator and species of prey. Meal size did not affect detection time, except when fourth instar individuals of H. axyridis were fed 10 eggs or one second instar of C. carnea. Predator weight, sex and morpho-type (melanic/non-melanic) did not influence DNA detection. The half-life of the time for which the DNA of the prey remained detectable was calculated for each predator-prey combination, and ranged from 8.9 to 52.4 h. This method can be used to study the ecological importance of IGP by H. axyridis on aphidophagous predators other than coccinellids in the field., Brecht Ingels ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28. Occurrence of Harmonia axyridis (Coleoptera: Coccinellidae) in field crops
- Creator:
- Vandereycken, Axel, Brostaux, Yves, Joie, Emilie, Haubruge, Eric, and Verheggen, Francois J.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, habitat, crops, agroecosystems, ladybird, exotic species, 2, and 59
- Language:
- English
- Description:
- The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of this exotic species and its seasonal abundance in various field crops. The abundance of adults, larvae and pupae of H. axyridis was evaluated over a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. From May to September, 48 1-m² quadrats were visually inspected in each of the fields sampled on several farms every seven days. H. axyridis colonized and reproduced in all of the four crops studied, with the largest numbers recorded in corn and broad bean crops. Larvae and adults of H. axyridis were recorded mainly in corn and to a much less extent in wheat and potato crops. From 2009 to 2011, the mean weekly abundance of H. ayxridis remained constant except in corn crops, where the recorded densities of all the immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis are well described by a symmetric logistic function (S-shape) of cumulative population size. H. axyridis was not always recorded where aphids were abundant, e.g. aphids were abundant on wheat where no H. axyridis were recorded. H. axyridis start reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of the same and other species of ladybird and other aphidophagous species. H. axyridis is often considered to be bivoltine but it only completes one generation per year in field crops. The second generation generally develops late in the season in other habitats., Axel Vandereycken ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
29. Parameters of reproductive activity in females of Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Stathas, George J., Eliopoulos, Panagiotis A., Kontodimas, Dimitrios C., and Giannopapas, John
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellidae, Harmonia axyridis, reproductive activity, fecundity, mating, number of ovarioles, batch size, Aphis fabae, and temperature
- Language:
- English
- Description:
- The effects of temperatures of 15, 20, 25 and 30°C on the duration of premating and preoviposition periods of Harmonia axyridis reared on the aphid Aphis fabae, were compared in the laboratory. The course of oviposition was monitored at 25°C in females reared on Aphis fabae and the peak of egg laying was recorded at the age of 15 to 45 days. The size of egg groups (batch size), as well as daily and total fecundity was recorded. Half of the total number of eggs was laid in batches of 10-30 eggs. The mean daily and total fecundity reached a maximum of 42 and 1,641.6 eggs, respectively. Adult females oviposited for almost their entire life.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
30. Parasitylenchus sp. (Tylenchomorpha: Allantonematidae) parasitizing field populations of Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Harding, Susanne, Poinar, George, Dimitrova, Desislava V., and Steenberg, Tove
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Coccinellidae, Harmonia axyridis, parasitic nematodes, Allantonematidae, Parasitylenchus sp., field parasitism, invasive species, 2, and 59
- Language:
- English
- Description:
- Adults of the invasive harlequin ladybird, Harmonia axyridis (Coleoptera: Coccinellidae), were found to be parasitized by nematodes (Tylenchomorpha: Allantonematidae) in Denmark. The nematodes were identified as Parasitylenchus sp. Major morphological characters of the nematodes did not differ significantly from Parasitylenchus coccinellinae Iperti & van Waerebeke 1968, but minor deviations in egg dimension and tail length were measured. Parasitism was only recorded in early autumn, with prevalence ranging from 2 to 33%. Adult and juvenile nematodes occurred together in the body cavity of both female and male H. axyridis. and Susanne Harding, George O. Poinar, Desislava V. Dimitrova, Tove Steenberg.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public