Agricultural intensification (AI) is currently a major driver of biodiversity loss and related ecosystem functioning decline. However, spatio-temporal changes in community structure induced by AI, ...and their relation to ecosystem functioning, remain largely unexplored. Here, we analysed 16 quantitative cereal aphid-parasitoid and parasitoid-hyperparasitoid food webs, replicated four times during the season, under contrasting AI regimes (organic farming in complex landscapes vs. conventional farming in simple landscapes). High AI increased food web complexity but also temporal variability in aphid-parasitoid food webs and in the dominant parasitoid species identity. Enhanced complexity and variability appeared to be controlled bottom-up by changes in aphid dominance structure and evenness. Contrary to the common expectations of positive biodiversity-ecosystem functioning relationships, community complexity (food-web complexity, species richness and evenness) was negatively related to primary parasitism rates. However, this relationship was positive for secondary parasitoids. Despite differences in community structures among different trophic levels, ecosystem services (parasitism rates) and disservices (aphid abundances and hyperparasitism rates) were always higher in fields with low AI. Hence, community structure and ecosystem functioning appear to be differently influenced by AI, and change differently over time and among trophic levels. In conclusion, intensified agriculture can support diverse albeit highly variable parasitoid-host communities, but ecosystem functioning might not be easy to predict from observed changes in community structure and composition.
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•Two species new to science are described within this manuscript.•Both species discovered from the Naturalis Biodiversity Center collection.•Toxares fovealis sp.n. from Europe ...(Netherlands).•Aphidius breviflagellaris sp. n. from Asia (South Korea).•Morphological and genetic variability of Toxares deltiger Haliday is disscussed.
The genera Aphidius Nees, 1818 and Toxares Haliday, 1840 both belong to the subfamily Aphidiinae, a group whose members are obligatory koinobiont endoparasitoids of aphids (Hemiptera, Aphididae). While Toxares is a small genus with only five known species from the Holarctic and Oriental regions, Aphidius is the most diverse within the subfamily with more than 130 recognised species distributed worldwide. Here we describe two new species discovered in the collection of Naturalis Biodiversity Center: Toxares fovealis sp.n. from Europe (the Netherlands) and Aphidius breviflagellaris sp.n. from Eastern Asia (South Korea). We also analyse genetic and morphological variability of Toxares deltiger (Haliday, 1833) specimens collected in Europe and redescribe the species.
The aim of this study was to reveal the diversity of parasitoids and ascertain tritrophic parasitoid-host aphid-host plant interactions in a lagoon habitat very close to orchards, vegetable gardens, ...and cereal fields in the Çanakkale Province of northwest Turkey between April and September from 2020 to 2021. In total, 23 tritrophic parasitoid-host aphid-host plant interactions, including new association records for Europe and Turkey, were revealed on 12 parasitoid species belonging to six genera from the subfamily Aphidiinae (Hymenoptera: Braconidae) reared from 15 aphid species (Hemiptera: Aphididae) on 17 host plants from different plant families. Also, we present three tritrophic parasitoid-host aphid-host plant interactions new for Europe and five tritrophic interactions new for Turkey. Of the identified parasitoid species,
Aphidius
(
Aphidius
)
artemisicola
Tizado et Nunez-Perez, 1994 is recorded for the first time for the parasitoid fauna of Turkey. A morphological diagnosis of the newly recorded parasitoid is provided. The results of this study of the tritrophic interactions between parasitoids and their aphid hosts on host plants in a lagoon habitat enable us to more meaningfully interpret these interactions and provide data of potential significance for the biological control of pest aphids in the region. These results showed that research on the interactions of parasitoids and their host aphids on non-crop host plants in non-crop areas close to crop fields can yield data of potential significance for the biological control of aphids in agriculture.
The aim of this study was to investigate how the primary (PHP) and secondary host plants (SHP) in the fruit orchards affect the interactions of aphids and their parasitoids in northwest Turkey during ...spring and summer 2020 and 2021. In total, 67 tritrophic aphid–parasitoid-host plant interactions, including new association records for Europe and Turkey, were obtained from 16 parasitoid species from the subfamily Aphidiinae (Hymenoptera: Braconidae) reared from 25 aphid species (Hemiptera: Aphididae) on 22 PHP and SHP in the fruit orchards. Also, we evaluated the effect of the PHP and SHP on the parasitoids, aphids and their interactions. We revealed that the species richness and the values of the biodiversity indices of the parasitoids and aphids were significantly higher on the SHP than the PHP. Similarly, the aphid–parasitoid interactions on the SHP showed greater diversity than the PHP. The results of this study clearly show that the interactions of parasitoids and aphids in the fruit orchards were more diverse on the SHP compared to the PHP.
In the present study, the natural enemies of aphids (Hemiptera: Aphididae) and their host plants including herbaceous plants, shrubs and trees were analysed to reveal their biodiversity and disclose ...tritrophic associations in different habitats of the South Marmara region of northwest Turkey. As a result of field surveys, 58 natural enemy species associated with 43 aphids on 58 different host plants were identified in the region between March of 2017 and November of 2018. In 173 tritrophic natural enemy-aphid-host plant interactions including association records new for Europe and Turkey, there were 21 representatives of the family Coccinellidae (Coleoptera), 14 of the family Syrphidae (Diptera) and 15 of the subfamily Aphidiinae (Hymenoptera), as well as eight other generalist natural enemies. In these interactions, a total of 37 aphid-natural enemy associations–including 19 associations of
Acyrthosiphon pisum
(Harris) with natural enemies, 16 associations of
Therioaphis trifolii
(Monell) with natural enemies and two associations of
Aphis craccivora
Koch with natural enemies–were detected on
Medicago sativa
L. during the sampling period. Similarly, 12 associations of
Myzus cerasi
(Fabricius) with natural enemies were revealed on
Prunus avium
(L.), along with five associations of
Brevicoryne brassicae
(Linnaeus) with natural enemies (including mostly parasitoid individuals) on
Brassica oleracea
L. Also in the study, reduviids of the species
Zelus renardii
(Kolenati) are reported for the first time as new potential aphid biocontrol agents in Turkey. The results of field surveys show that the natural enemies of aphids have high biodiversity, which should be considered in the management of biological pest control.
The braconid genus Dyscritulus Hincks is a small member of the subfamily Aphidiinae, distributed in Europe and Central Asia. All its species are highly specialized parasitoids of aphids of the genera ...Drepanosiphum Koch and, probably, Periphyllus van der Hoeven which are mostly associated with maple and sycamore trees (genus Acer ). Upon examination of specimens from the Naturalis Biodiversity Center, Leiden, we unexpectedly noted unusual variability in morphological characters compared to other known Dyscritulus species. Further inspection of other material previously identified as Dyscritulus planiceps Marshall, 1896 revealed additional specimens with the same morphological variability. Here we describe a new species of the genus, Dyscritulus europaeus sp. nov. , associated with Drepanosiphum aphids on Acer .
is an important biological control agent, used in greenhouses and open fields against aphid pests. Despite this economical importance,
, along with
and
, has gone through a complex taxonomical ...history. The three species have only recently gained status as separate species again, comprising the morphologically defined
species group. Other than sporadic records probably as a consequence of escape from greenhouses, the
species group members prefer warmer regions and there are numerous records from South America, Southern Europe and Asia. Based on slide-mounted material collected in the period 1964-2001 in Africa, we describe five new species belonging to this group, and report
and
from several African countries. This data opens questions about the origin of the group and presents potential for the diversification of biological control agents against aphid pests.
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 host-use 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.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this study two molecular markers were used to establish taxonomic status and phylogenetic relationships of
Ephedrus
subgenera and species distributed in Europe. Fifteen of the nineteen currently ...known species have been analysed, representing three subgenera:
Breviephedrus
Gärdenfors, 1986,
Lysephedrus
Starý, 1958 and
Ephedrus
Haliday, 1833. The results of analysis of COI and EF1α molecular markers and morphological studies did not support this classification. Three clades separated by the highest genetic distances reported for the subfamily Aphidiinae on intrageneric level.
Ephedrus brevis
is separated from
persicae
and
plagiator
species groups with genetic distances of 19.6 % and 16.3 % respectively, while the distance between
persicae
and
plagiator
groups was 20.7 %. These results lead to the conclusion that the traditional subgeneric classification of
Ephedrus
needs revision. Species from
persicae
species group are raised to subgenus level as
Fovephedrus
Chen, 1986 and
Lysephedrus
syn. nov.
is assigned as a junior synonym of subgenus Ephedrus. Key for identification of
Ephedrus
subgenera is provided.
Ephedrus hyadaphidis
Kocić & Tomanović
sp. nov.
is described and several species are confirmed as valid species for the first time. Furthermore, two species are synonymised:
E. dysaphidis
syn. nov.
as a junior synonym of
E. cerasicola
and
E. blattnyi
syn. nov.
as a junior synonym of
E. plagiator
.
The genus
Haliday, 1833 is a small group which consists of 24 species worldwide. In South Korea, Chang and Youn (1983) recorded one species,
Starý & Schlinger, 1967, but the evidence for ...identification of this species is doubtful and further confirmation is required (personal communication with Prof. Jong-Cheol Paik).
An additional
species is recorded as new to science from South Korea. Descriptions and illustrations of the new species -
sp. nov. - are provided, together with its mitochondrial
(
) data and phylogenetic position. A key to the female of the two species present in Korea is provided.
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