TY  - JOUR
AU  - Janković, M.
AU  - Plecas, M.
AU  - Sandić, D.
AU  - Popović, A.
AU  - Petrović, Andjeljko
AU  - Petrović-Obradović, Olivera
AU  - Tomanović, Željko
AU  - Gagić, V.
PY  - 2017
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4361
AB  - The functional roles of different habitats may depend on the combined effect of local habitat management and the structure and composition of the surrounding landscape. However, this interaction is not well understood due to the common practice of pooling many different habitat types in one simple landscape metric (e.g., percentage crop area). In this study, we investigate the interactive effects of local and landscape factors on the abundance and species richness of aphids and their natural enemies, as well as primary parasitism and hyperparasitism rates. We selected 41 fields in Central Serbia with three disturbance levels at the local scale (wheat fields, alfalfa fields, and fallows) embedded in 15 landscapes that varied in percentage of annual crops, grasslands, and shrublands. We found ecosystem disservices to be promoted in wheat fields, where both aphid abundances and hyperparasitism rates were approximately threefold higher than in alfalfa fields and fallows. Concurrently, alfalfa fields supported at least twofold higher primary parasitism rates and predator (coccinellid) abundances than either wheat fields or fallows. The proportion of grasslands in the surrounding landscape had no effect on any organism group while shrublands appear to be important for both polyphagus predators and pests in some crops, a pattern not revealed when all semi-natural habitats in the landscape are pooled together. Our results imply that the roles of different habitat types at both local and landscape scales should be considered in a multifunctional agricultural management approach, which if adopted may provide better ecosystem services for multiple agroecosystem types.
PB  - Springer Heidelberg, Heidelberg
T2  - Journal of Pest Science
T1  - Functional role of different habitat types at local and landscape scales for aphids and their natural enemies
EP  - 273
IS  - 1
SP  - 261
VL  - 90
DO  - 10.1007/s10340-016-0744-9
ER  - 

@article{
author = "Janković, M. and Plecas, M. and Sandić, D. and Popović, A. and Petrović, Andjeljko and Petrović-Obradović, Olivera and Tomanović, Željko and Gagić, V.",
year = "2017",
abstract = "The functional roles of different habitats may depend on the combined effect of local habitat management and the structure and composition of the surrounding landscape. However, this interaction is not well understood due to the common practice of pooling many different habitat types in one simple landscape metric (e.g., percentage crop area). In this study, we investigate the interactive effects of local and landscape factors on the abundance and species richness of aphids and their natural enemies, as well as primary parasitism and hyperparasitism rates. We selected 41 fields in Central Serbia with three disturbance levels at the local scale (wheat fields, alfalfa fields, and fallows) embedded in 15 landscapes that varied in percentage of annual crops, grasslands, and shrublands. We found ecosystem disservices to be promoted in wheat fields, where both aphid abundances and hyperparasitism rates were approximately threefold higher than in alfalfa fields and fallows. Concurrently, alfalfa fields supported at least twofold higher primary parasitism rates and predator (coccinellid) abundances than either wheat fields or fallows. The proportion of grasslands in the surrounding landscape had no effect on any organism group while shrublands appear to be important for both polyphagus predators and pests in some crops, a pattern not revealed when all semi-natural habitats in the landscape are pooled together. Our results imply that the roles of different habitat types at both local and landscape scales should be considered in a multifunctional agricultural management approach, which if adopted may provide better ecosystem services for multiple agroecosystem types.",
publisher = "Springer Heidelberg, Heidelberg",
journal = "Journal of Pest Science",
title = "Functional role of different habitat types at local and landscape scales for aphids and their natural enemies",
pages = "273-261",
number = "1",
volume = "90",
doi = "10.1007/s10340-016-0744-9"
}

Janković, M., Plecas, M., Sandić, D., Popović, A., Petrović, A., Petrović-Obradović, O., Tomanović, Ž.,& Gagić, V.. (2017). Functional role of different habitat types at local and landscape scales for aphids and their natural enemies. in Journal of Pest Science
Springer Heidelberg, Heidelberg., 90(1), 261-273.
https://doi.org/10.1007/s10340-016-0744-9

Janković M, Plecas M, Sandić D, Popović A, Petrović A, Petrović-Obradović O, Tomanović Ž, Gagić V. Functional role of different habitat types at local and landscape scales for aphids and their natural enemies. in Journal of Pest Science. 2017;90(1):261-273.
doi:10.1007/s10340-016-0744-9 .

Janković, M., Plecas, M., Sandić, D., Popović, A., Petrović, Andjeljko, Petrović-Obradović, Olivera, Tomanović, Željko, Gagić, V., "Functional role of different habitat types at local and landscape scales for aphids and their natural enemies" in Journal of Pest Science, 90, no. 1 (2017):261-273,
https://doi.org/10.1007/s10340-016-0744-9 . .

TY  - JOUR
AU  - Gagić, Vesna
AU  - Petrović-Obradović, Olivera
AU  - Fruend, Jochen
AU  - Kavallieratos, Nickolas G.
AU  - Athanassiou, Christos G.
AU  - Stary, Petr
AU  - Tomanović, Željko
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4105
AB  - Specialization is a central concept in ecology and one of the fundamental properties of parasitoids. Highly specialized parasitoids tend to be more efficient in host-use compared to generalized parasitoids, presumably owing to the trade-off between host range and hostuse efficiency. However, it remains unknown how parasitoid host specificity and host-use depends on host traits related to susceptibility to parasitoid attack. To address this question, we used data from a 13-year survey of interactions among 142 aphid and 75 parasitoid species in nine European countries. We found that only aphid traits related to local resource characteristics seem to influence the trade-off between host-range and efficiency: more specialized parasitoids had an apparent advantage (higher abundance on shared hosts) on aphids with sparse colonies, ant-attendance and without concealment, and this was more evident when host relatedness was included in calculation of parasitoid specificity. More traits influenced average assemblage specialization, which was highest in aphids that are monophagous, monoecious, large, highly mobile (easily drop from a plant), without myrmecophily, habitat specialists, inhabit non-agricultural habitats and have sparse colonies. Differences in aphid wax production did not influence parasitoid host specificity and host-use. Our study is the first step in identifying host traits important for aphid parasitoid host specificity and host-use and improves our understanding of bottom-up effects of aphid traits on aphid-parasitoid food web structure.
PB  - Public Library Science, San Francisco
T2  - Plos One
T1  - The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage
IS  - 6
VL  - 11
DO  - 10.1371/journal.pone.0157674
ER  - 

@article{
author = "Gagić, Vesna and Petrović-Obradović, Olivera and Fruend, Jochen and Kavallieratos, Nickolas G. and Athanassiou, Christos G. and Stary, Petr and Tomanović, Željko",
year = "2016",
abstract = "Specialization is a central concept in ecology and one of the fundamental properties of parasitoids. Highly specialized parasitoids tend to be more efficient in host-use compared to generalized parasitoids, presumably owing to the trade-off between host range and hostuse efficiency. However, it remains unknown how parasitoid host specificity and host-use depends on host traits related to susceptibility to parasitoid attack. To address this question, we used data from a 13-year survey of interactions among 142 aphid and 75 parasitoid species in nine European countries. We found that only aphid traits related to local resource characteristics seem to influence the trade-off between host-range and efficiency: more specialized parasitoids had an apparent advantage (higher abundance on shared hosts) on aphids with sparse colonies, ant-attendance and without concealment, and this was more evident when host relatedness was included in calculation of parasitoid specificity. More traits influenced average assemblage specialization, which was highest in aphids that are monophagous, monoecious, large, highly mobile (easily drop from a plant), without myrmecophily, habitat specialists, inhabit non-agricultural habitats and have sparse colonies. Differences in aphid wax production did not influence parasitoid host specificity and host-use. Our study is the first step in identifying host traits important for aphid parasitoid host specificity and host-use and improves our understanding of bottom-up effects of aphid traits on aphid-parasitoid food web structure.",
publisher = "Public Library Science, San Francisco",
journal = "Plos One",
title = "The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage",
number = "6",
volume = "11",
doi = "10.1371/journal.pone.0157674"
}

Gagić, V., Petrović-Obradović, O., Fruend, J., Kavallieratos, N. G., Athanassiou, C. G., Stary, P.,& Tomanović, Ž.. (2016). The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage. in Plos One
Public Library Science, San Francisco., 11(6).
https://doi.org/10.1371/journal.pone.0157674

Gagić V, Petrović-Obradović O, Fruend J, Kavallieratos NG, Athanassiou CG, Stary P, Tomanović Ž. The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage. in Plos One. 2016;11(6).
doi:10.1371/journal.pone.0157674 .

Gagić, Vesna, Petrović-Obradović, Olivera, Fruend, Jochen, Kavallieratos, Nickolas G., Athanassiou, Christos G., Stary, Petr, Tomanović, Željko, "The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage" in Plos One, 11, no. 6 (2016),
https://doi.org/10.1371/journal.pone.0157674 . .

TY  - JOUR
AU  - Plecas, M.
AU  - Gagić, V.
AU  - Janković, M.
AU  - Petrović-Obradović, Olivera
AU  - Kavallieratos, Nickolas G.
AU  - Tomanović, Željko
AU  - Thies, C.
AU  - Tscharntke, T.
AU  - Cetković, A.
PY  - 2014
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3541
AB  - The loss of landscape heterogeneity through agricultural intensification is known to affect aphid-parasitoid-hyperparasitoid interactions, with consequences for biological control. Various aspects of landscape heterogeneity (e.g. landscape composition and configuration) are expected to affect these interactions differentially, but there were few attempts to empirically compare the influence of separate landscape features on pest-parasitoid dynamics. To address these questions, we conducted three simultaneous studies in wheat fields in northern Serbia, to compare the effects of contrasting landscape contexts: (1) simple vs. more complex landscapes; (2) large- vs. small-field landscapes; (3) large-field areas with contrasting character of their marginal vegetation. We (1) found that aphid densities, parasitism rates and species richness of parasitoids and hyperparasitoids were higher in landscapes with more extensive and diversified non-crop habitats, positively affecting the biological control. We (2) did not find significant differences in aphid abundance and parasitism between large- and small-field landscapes, but we detected some contradictory patterns in aphid growth and parasitism increase; we relate both findings to certain region-specific landscape features of wider relevance. The character of marginal vegetation (3) had mixed effects on aphid-parasitoid interactions and dynamics, with respect to source of colonization. Parasitism rates above 22-24% were associated with population decline in the aphids, consistently across analyzed landscape contrasts. Other relationships were subject to significant inter-annual variability (over 2-4 years period), suggesting that effectiveness of landscape management for conservation biological control would also fluctuate year by year. Our findings show that a well-founded landscape-scale management for biological pest control in agriculture must be adjusted for differential aspects of landscape heterogeneity effects on pest-parasitoid interactions.
PB  - Elsevier Science Bv, Amsterdam
T2  - Agriculture Ecosystems & Environment
T1  - Landscape composition and configuration influence cereal aphid-parasitoid-hyperparasitoid interactions and biological control differentially across years
EP  - 10
SP  - 1
VL  - 183
DO  - 10.1016/j.agee.2013.10.016
ER  - 

@article{
author = "Plecas, M. and Gagić, V. and Janković, M. and Petrović-Obradović, Olivera and Kavallieratos, Nickolas G. and Tomanović, Željko and Thies, C. and Tscharntke, T. and Cetković, A.",
year = "2014",
abstract = "The loss of landscape heterogeneity through agricultural intensification is known to affect aphid-parasitoid-hyperparasitoid interactions, with consequences for biological control. Various aspects of landscape heterogeneity (e.g. landscape composition and configuration) are expected to affect these interactions differentially, but there were few attempts to empirically compare the influence of separate landscape features on pest-parasitoid dynamics. To address these questions, we conducted three simultaneous studies in wheat fields in northern Serbia, to compare the effects of contrasting landscape contexts: (1) simple vs. more complex landscapes; (2) large- vs. small-field landscapes; (3) large-field areas with contrasting character of their marginal vegetation. We (1) found that aphid densities, parasitism rates and species richness of parasitoids and hyperparasitoids were higher in landscapes with more extensive and diversified non-crop habitats, positively affecting the biological control. We (2) did not find significant differences in aphid abundance and parasitism between large- and small-field landscapes, but we detected some contradictory patterns in aphid growth and parasitism increase; we relate both findings to certain region-specific landscape features of wider relevance. The character of marginal vegetation (3) had mixed effects on aphid-parasitoid interactions and dynamics, with respect to source of colonization. Parasitism rates above 22-24% were associated with population decline in the aphids, consistently across analyzed landscape contrasts. Other relationships were subject to significant inter-annual variability (over 2-4 years period), suggesting that effectiveness of landscape management for conservation biological control would also fluctuate year by year. Our findings show that a well-founded landscape-scale management for biological pest control in agriculture must be adjusted for differential aspects of landscape heterogeneity effects on pest-parasitoid interactions.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Agriculture Ecosystems & Environment",
title = "Landscape composition and configuration influence cereal aphid-parasitoid-hyperparasitoid interactions and biological control differentially across years",
pages = "10-1",
volume = "183",
doi = "10.1016/j.agee.2013.10.016"
}

Plecas, M., Gagić, V., Janković, M., Petrović-Obradović, O., Kavallieratos, N. G., Tomanović, Ž., Thies, C., Tscharntke, T.,& Cetković, A.. (2014). Landscape composition and configuration influence cereal aphid-parasitoid-hyperparasitoid interactions and biological control differentially across years. in Agriculture Ecosystems & Environment
Elsevier Science Bv, Amsterdam., 183, 1-10.
https://doi.org/10.1016/j.agee.2013.10.016

Plecas M, Gagić V, Janković M, Petrović-Obradović O, Kavallieratos NG, Tomanović Ž, Thies C, Tscharntke T, Cetković A. Landscape composition and configuration influence cereal aphid-parasitoid-hyperparasitoid interactions and biological control differentially across years. in Agriculture Ecosystems & Environment. 2014;183:1-10.
doi:10.1016/j.agee.2013.10.016 .

Plecas, M., Gagić, V., Janković, M., Petrović-Obradović, Olivera, Kavallieratos, Nickolas G., Tomanović, Željko, Thies, C., Tscharntke, T., Cetković, A., "Landscape composition and configuration influence cereal aphid-parasitoid-hyperparasitoid interactions and biological control differentially across years" in Agriculture Ecosystems & Environment, 183 (2014):1-10,
https://doi.org/10.1016/j.agee.2013.10.016 . .