Memorias del presente: vida, muerte y resistencia en Ciudad Juárez

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Conserving European biodiversity across realms

Terrestrial, freshwater, and marine ecosystems are connected via multiple biophysical and ecological processes. Identifying and quantifying links among ecosystems is necessary for the uptake of integrated conservation actions across realms. Such actions are particularly important for species using habitats in more than one realm during their daily or life cycle. We reviewed information on the habitats of 2,408 species of European conservation concern and found that 30% of the species use habitats in multiple realms. Transportation and service corridors, which fragment species habitats, were identified as the most important threat impacting ∼70% of the species. We examined information on 1,567 European Union (EU) conservation projects funded over the past 25 years, to assess the adequacy of efforts toward the conservation of “multi‐realm” species at a continental scale. We discovered that less than a third of multi‐realm species benefited from projects that included conservation actions across multiple realms. To achieve the EU's conservation target of halting biodiversity loss by 2020 and effectively protect multi‐realm species, integrated conservation efforts across realms should be reinforced by: (1) recognizing the need for integrated management at a policy level, (2) revising conservation funding priorities across realms, and (3) implementing integrated land‐freshwater‐sea conservation planning and management

Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field

Effects of elevated CO₂ on an insect omnivore : a test for nutritional effects mediated by host plants and prey

Elevated atmospheric CO₂ has generally been found to have negative impacts on the performance of insect herbivores via negative effects on plant quality. Yet, reduced food quality may lead to an increase in crop damage when pests compensate by consuming more plant tissue. The flow-on effects of elevated CO₂ level on higher trophic levels have rarely been investigated. We tested the effects of elevated CO₂ on the behavior and performance of the omnivorous bug Oechalia schellenbergii (Heteroptera: Pentatomidae) and its prey, a polyphagous chewing herbivorous pest (Helicoverpa armigera; Lepidoptera: Noctuidae), feeding on pea (Pisum sativum) foliage. We hypothesized that elevated CO₂ would impose negative nutritional effects on the omnivore by lowering the quality of plants, the prey, or both. Plants grown at elevated CO₂ were significantly larger, with reduced N content, than plants grown at ambient CO₂. H. armigera larvae feeding on elevated CO₂-grown plants were significantly smaller than those grown on ambient-grown plants, but prey N content did not differ between CO₂ treatments. The omnivore required prey to complete its development, and performed best on a mixed plant-prey diet, regardless of CO₂ level. Bugs that failed to reach adulthood were slower to develop on the elevated CO₂–prey diet; those that successfully eclosed were not affected by CO₂ treatment in terms of development time, adult weight, adult longevity, hatch rate or pre-oviposition time. The bugs did not display compensatory feeding when offered prey of similar size from different CO₂ treatments. The bugs performed best when fed larvae from the elevated-CO₂ treatment apparently because these prey were smaller and thus easier to subdue. Taken together, results indicate that elevated CO₂ may benefit generalist predators through increased prey vulnerability, which would put pest species under higher risk of predation.9 page(s

Considering the Geographic Diversity of Natural Enemy Traits in Biological Control: A Quantitative Approach Using Orius Predators as an Example

The desirable characteristics of effective natural enemies and the causes for failure of biological control efforts have been discussed extensively in the literature, yet predicting which collection site may yield efficient natural enemies remains a challenge. Insect characteristics, such as morphology, physiology, life history and behavior, often vary across geographic cline and location. These variations may reflect phenotypic plasticity across environments, or genetically based local (demic) adaptation. Parameters such as body size, photoperiod response, thermal tolerance and genetic diversity may greatly influence the outcome of biological control efforts. Therefore, geographic variation in such characteristics may be used to optimize the collection site of efficient enemies to be employed in biological control programs. The first step towards this goal is compilation of data on the trait diversity of promising natural enemies across their geographic distribution range. For example, we used published information to compile a database on the geographic distribution of various traits of 92 Orius species (Heteroptera: Anthocoridae), a genus known for its potential contribution to biological control in IPM systems. We discuss how the widespread distribution of this genus in different ecozones should enable the collection of species and populations that differ in various geographically dependent traits relevant to biological control. Finally, we suggest a quantitative method to optimize collection efforts of natural enemies. This approach balances the effects of several natural enemy traits that vary geographically. Lastly, we demonstrate the use of this method by evaluating the potential employment of two geographically distinct populations of O. albidipennis

Effects of Global Warming on Predatory Bugs Supported by Data Across Geographic and Seasonal Climatic Gradients

Global warming may affect species abundance and distribution, as well as temperature-dependent morphometric traits. In this study, we first used historical data to document changes in Orius (Heteroptera: Anthocoridae) species assemblage and individual morphometric traits over the past seven decades in Israel. We then tested whether these changes could have been temperature driven by searching for similar patterns across seasonal and geographic climatic gradients in a present survey. The historical records indicated a shift in the relative abundance of dominant Orius species; the relative abundance of O. albidipennis, a desert-adapted species, increased while that of O. laevigatus decreased in recent decades by 6 and 10–15 folds, respectively. These shifts coincided with an overall increase of up to 2.1°C in mean daily temperatures over the last 25 years in Israel. Similar trends were found in contemporary data across two other climatic gradients, seasonal and geographic; O. albidipennis dominated Orius assemblages under warm conditions. Finally, specimens collected in the present survey were significantly smaller than those from the 1980’s, corresponding to significantly smaller individuals collected now during warmer than colder seasons. Taken together, results provide strong support to the hypothesis that temperature is the most likely driver of the observed shifts in species composition and body sizes because (1) historical changes in both species assemblage and body size were associated with rising temperatures in the study region over the last few decades; and (2) similar changes were observed as a result of contemporary drivers that are associated with temperature

Considering the Geographic Diversity of Natural Enemy Traits in Biological Control: A Quantitative Approach Using <i>Orius</i> Predators as an Example

The desirable characteristics of effective natural enemies and the causes for failure of biological control efforts have been discussed extensively in the literature, yet predicting which collection site may yield efficient natural enemies remains a challenge. Insect characteristics, such as morphology, physiology, life history and behavior, often vary across geographic cline and location. These variations may reflect phenotypic plasticity across environments, or genetically based local (demic) adaptation. Parameters such as body size, photoperiod response, thermal tolerance and genetic diversity may greatly influence the outcome of biological control efforts. Therefore, geographic variation in such characteristics may be used to optimize the collection site of efficient enemies to be employed in biological control programs. The first step towards this goal is compilation of data on the trait diversity of promising natural enemies across their geographic distribution range. For example, we used published information to compile a database on the geographic distribution of various traits of 92 Orius species (Heteroptera: Anthocoridae), a genus known for its potential contribution to biological control in IPM systems. We discuss how the widespread distribution of this genus in different ecozones should enable the collection of species and populations that differ in various geographically dependent traits relevant to biological control. Finally, we suggest a quantitative method to optimize collection efforts of natural enemies. This approach balances the effects of several natural enemy traits that vary geographically. Lastly, we demonstrate the use of this method by evaluating the potential employment of two geographically distinct populations of O. albidipennis.</i

Negative Effects of <i>Phthorimaea absoluta</i>-Resistant Tomato Genotypes on the Zoophytophagous Biocontrol Agent, <i>Orius laevigatus</i> (Fieber) (Hemiptera: Anthocoridae)

Complex interactions between host plant resistance (HPR) and biological control agents, particularly omnivorous predators, can shape the outcome of an integrated pest management (IPM) program. However, such interactions are seldom explored during plant breeding programs. Therefore, in the present study, we compared the performance of the omnivorous biological control agent Orius laevigatus on six tomato genotypes with different levels of resistance to the tomato leaf miner Phthorimaea absoluta. We found that the O. laevigatus fitness components (i.e., egg deposition, egg hatching rate, and duration of egg, early nymphal, late nymphal stages, and their survival) were inferior on the wild resistant genotypes (LA 716 and LA 1777) in comparison to the resistant domesticated genotype EC 620343 and the susceptible genotypes (EC 705464 and EC 519819). It appears that the adverse effects of tomato genotypes on O. laevigatus are determined mainly by glandular and non-glandular trichome densities on the leaves. Comparison of O. laevigatus response to the tested tomato cultivars to that of P. absoluta revealed significant positive correlations in duration of the egg stages, development time of early and late larval stages, and overall immature mortality in both species. It appears, therefore, that defensive plant traits operate in a similar way on the pest and its predator in the system. Overall, the present study of the tomato-P. absoluta-O. laevigatus system provides experimental evidence for the need to optimize pest management by employing intermediate levels of crop resistance together with biological control agents

Negative Effects of Phthorimaea absoluta-Resistant Tomato Genotypes on the Zoophytophagous Biocontrol Agent, Orius laevigatus (Fieber) (Hemiptera: Anthocoridae)

Complex interactions between host plant resistance (HPR) and biological control agents, particularly omnivorous predators, can shape the outcome of an integrated pest management (IPM) program. However, such interactions are seldom explored during plant breeding programs. Therefore, in the present study, we compared the performance of the omnivorous biological control agent Orius laevigatus on six tomato genotypes with different levels of resistance to the tomato leaf miner Phthorimaea absoluta. We found that the O. laevigatus fitness components (i.e., egg deposition, egg hatching rate, and duration of egg, early nymphal, late nymphal stages, and their survival) were inferior on the wild resistant genotypes (LA 716 and LA 1777) in comparison to the resistant domesticated genotype EC 620343 and the susceptible genotypes (EC 705464 and EC 519819). It appears that the adverse effects of tomato genotypes on O. laevigatus are determined mainly by glandular and non-glandular trichome densities on the leaves. Comparison of O. laevigatus response to the tested tomato cultivars to that of P. absoluta revealed significant positive correlations in duration of the egg stages, development time of early and late larval stages, and overall immature mortality in both species. It appears, therefore, that defensive plant traits operate in a similar way on the pest and its predator in the system. Overall, the present study of the tomato-P. absoluta-O. laevigatus system provides experimental evidence for the need to optimize pest management by employing intermediate levels of crop resistance together with biological control agents