97 research outputs found
Searching for new predators of the invasive Halyomorpha halys: the role of the black garden ant Lasius niger
In recent years, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae, Cappaeini) has become an invasive pest in North America and Europe, where it caused extensive damage to agriculture, resulting in great economic losses. Evaluating the potential of native predators in the invaded areas, ants might represent good candidates thanks to their biology, ecology, and behavior. In Italy, H. halys proved to be the top key pest in pear orchards, where the black garden ant, Lasius niger (L.) (Hymenoptera: Formicidae, Lasiini), is the most abundant ant species. The aim of this study was to evaluate the predatory ability of L. niger on the eggs and on all the juvenile instars of H. halys under laboratory conditions. The results indicate that L. niger significantly reduces the survival of the second and third nymphal instars by 56 and 58%, respectively, but it is unable to reduce the egg hatching and the survival of the first, fourth, and fifth instars. Our preliminary results obtained in laboratory conditions suggest a possible role of the ant L. niger in controlling H. halys invasion mainly acting on the smaller and more mobile nymphal stages. The effective role of this species as potential biocontrol agents of H. halys in fruit orchards in association with other ant species as well as with other predatory insects is discussed
Unlike rolling stones: not every Myrmecina species actively rolls away from danger (Hymenoptera, Formicidae)
Actively rolling away is a very rare escape strategy in the animal kingdom, which to date has only been documented in a few arthropod and one vertebrate species. One of these arthropods is a West-Palearctic ant, Myrmecina graminicola, which has very recently been demonstrated to actively curb into a ball-like shape rolling away upon disturbance, and to selectively display this behavior only under particular circumstances. We tested whether one of the other three W-Palearctic Myrmecina species, the rare insular endemism M. sicula, exhibited the same behavioral response, using the same experimental approach used for M. graminicola. Our results showed that M. sicula reacted to moderate disturbance by either freezing its body or walking away. Only when the individual lost contact with the substratum, it could curl into a ball-like shape, yet this was significantly less refined than the one displayed by M. graminicola, as the appendages of M. sicula are not tightly kept close to its body. However, M. sicula never performed the active rolling behavior that is readily exhibited by M. graminicola. Ecological, morphological, and phylogenetic constraints may have determined the lack of a developed active rolling escape-strategy in M. sicula. Further investigations are required to assess the presence or absence of this unique behavior across Myrmecina lineages
First report on the acrobat ant Crematogaster scutellaris storing live aphids in its oak-gall nests
This study provides new data about the role of ants in mutualistic interactions with aphids mediated by galls. We focused our investigation on galls induced by the cynipid Andricus kollari by conducting a survey and a subsequent experiment in an Italian oak forest. The ants Crematogaster scutellaris, Colobopsis truncata and Temnothorax italicus frequently used the galls as nests: Crematogaster scutellaris occupied galls which were located higher on the oak trees, while C. truncata and T. italicus were located at lower positions. In addition, galls occupied by C. scutellaris showed varied internal architecture in relation to the colony composition. Importantly, field surveys revealed for the first time that C. scutellaris nest galls also contained live individuals of the non-galligenous aphid Panaphis juglandis. Field experiments suggested that the ants actively seek, collect and stock live aphids. No signs of predation and injuries were detected on the stored aphids, which were probably kept for safe overwintering, though we cannot exclude a possible occasional use as food. This report reveals a possible novel relationship which could have important consequences on the phenology and presence of aphids on the host plant
First report on the acrobat ant Crematogaster scutellaris storing live aphids in its oak-gall nests
This study provides new data about the role of ants in mutualistic interactions with aphids mediated by galls. We focused our investigation on galls induced by the cynipid Andricus kollari by conducting a survey and a subsequent experiment in an Italian oak forest. The ants Crematogaster scutellaris, Colobopsis truncata and Temnothorax italicus frequently used the galls as nests: Crematogaster scutellaris occupied galls which were located higher on the oak trees, while C. truncata and T. italicus were located at lower positions. In addition, galls occupied by C. scutellaris showed varied internal architecture in relation to the colony composition. Importantly, field surveys revealed for the first time that C. scutellaris nest galls also contained live individuals of the non-galligenous aphid Panaphis juglandis. Field experiments suggested that the ants actively seek, collect and stock live aphids. No signs of predation and injuries were detected on the stored aphids, which were probably kept for safe overwintering, though we cannot exclude a possible occasional use as food. This report reveals a possible novel relationship which could have important consequences on the phenology and presence of aphids on the host plant
Role of heme oxygenase-1 (HSP32) and HSP90 in glioblastoma
Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The current treatment regimes for glioblastoma demonstrated a low efficiency and offer a poor prognosis. Advancements in conventional treatment strategies have only yielded modest improvements in overall survival. The heat shockproteins, heme oxygenase-1 (HO-1) and Hsp90, serve these pivotal roles in tumor cells and have been identified as effective targets for developing therapeutics. This topic review summarizes the current preclinical and clinical evidences and rationale to define the potential of HO-1 and Hsp90 in GBM progression and chemoresistance
Assessing ant diversity in agroecosystems: The case of italian vineyards of the adige valley
Assessing ant diversity in agroecosystems: The case of Italian vineyards of the Adige Valley Agroecosystems have gained a dominant position on worldwide land-usage, and therefore preserving their biodiversity is crucial for environmental sustainability. Ants are one of the most widespread groups of terres-Trial arthropods, and, thanks to their significant diversification, they are considered as a good proxy group for bio-diversity monitoring, also in agroecosystems. Vineyards are economically valuable cultures widespread worldwide, and hosting many ant species, that provide meaningful ecosystem services and disservices. Despite the important role that ants play in these agroecosystems, ant biodiversity in vineyards is still poorly studied, especially in Italy. In this context, we present a first detailed quantitative and qualitative assessment of the ant fauna of Italian vine-yards from the Adige Valley based on pitfall traps data, and discuss the results in comparison with the few other similar assessments from Europe and other continents. We document an assemblage of 22 species (7-16 per or-chard), mostly dominated by three disturbance-Tolerant species (including an introduced species). Vineyards ant faunas appear to be rather heterogeneous worldwide, mainly following local ecological and biogeographical con-straints, and the role that most ant species play in these agroecosystems is presently unknown
A global database of ant species abundances
What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51, 388 ant abundance and occurrence records of more than 2,693 species and 7,953 morphospecies from local assemblages collected at 4,212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. Data were collected between 1949 and 2014, and include, for each geo-referenced sampling site, both the identity of the ants collected and details of sampling design, habitat type, and degree of disturbance. The aim of compiling this data set was to provide comprehensive species abundance data in order to test relationships between assemblage structure and environmental and biogeographic factors. Data were collected using a variety of standardized methods, such as pitfall and Winkler traps, and will be valuable for studies investigating large-scale forces structuring local assemblages. Understanding such relationships is particularly critical under current rates of global change. We encourage authors holding additional data on systematically collected ant assemblages, especially those in dry and cold, and remote areas, to contact us and contribute their data to this growing data set
Climate mediates the effects of disturbance on ant assemblage structure
Many studies have focused on the impacts of climate change on biological assemblages, yet little is known about howclimate interacts with other major anthropogenic influences on biodiversity, such as habitat disturbance. Using a unique global database of 1128 local ant assemblages, we examined whether climate mediates the effects of habitat disturbance on assemblage structure at a global scale. Species richness and evenness were associated positively with temperature, and negatively with disturbance. However, the interaction among temperature, precipitation and disturbance shaped species richness and evenness. The effectwas manifested through a failure of species richness to increase substantially with temperature in transformed habitats at low precipitation. At low precipitation levels, evenness increased with temperature in undisturbed sites, peaked at medium temperatures in disturbed sites and remained low in transformed sites. In warmer climates with lower rainfall, the effects of increasing disturbance on species richness and evenness were akin to decreases in temperature of up to 98C. Anthropogenic disturbance and ongoing climate change may interact in complicated ways to shape the structure of assemblages, with hot, arid environments likely to be at greatest risk. © 2015 The Author(s) Published by the Royal Society. All rights reserved
- …