Exploring the genetic resources of Lens and Rhizobium to improve the biological nitrogen fixation (BNF) ability in the lentil crop

Lentil plants (Lens culinaris) have the ability to obtain most of the N they need from N fixation by establishing an efficient symbiotic relationship with Rhizobium. Plant-based diets are gaining the recognition they deserve for sustainability and producing legumes without the use of synthetic N fertilizers is the most sustainable approach. The N fixing ability of representative lentil cultivars, as well as accessions from 6 wild Lens species, was evaluated to determine the potential for wild germplasm to contribute positively to breeding for improved BNF. The contributions of diverse Rhizobium strains from 5 species to lentil productivity under local field conditions was also investigated. Subsequently, the level of specificity of the interactions between Lens accessions and Rhizobium strains with desirable N fixing abilities was explored. How traits related to N fixation are inherited was determined in three interspecific RIL populations from parents displaying contrasting phenotypes. Differential N fixing ability was found among cultivars and wild accessions; no particular species stood out. Wild accessions exhibited indeterminate nodulation, root modifications that responded to different N sources, higher seed percentage protein content, and yields comparable to plants fertilized with synthetic N. CDC Greenstar was the only cultivar with similar yield when inoculated or fertilized. CDC Maxim inoculated with the strain NZLR-24 (Rhizobium leguminosarum bv. viciae) had 9% higher yield under field conditions compared to when inoculated the commercial strain BASF 1435 (Rlv) and 15% more compared to a non-inoculated treatment. Some wild accessions demonstrated a promiscuous ability to efficiently fix N with a broad set of strains, but no cultivar did. The higher effective capacity of the strain NZLR-24 (Rlv) was also evident when used to inoculate Lens from 6 species, making it a suitable option for improved inoculants in the Northern Great Plains, as well as showing its value for selection in future breeding efforts. The strain Oyali B (Rlv) was also noteworthy for its superior interaction with wild Lens, and it is an attractive wild-type resource. Sixteen QTL were identified for nodulation traits among the three interspecific populations; eight were meta-QTL found across two or more populations. Chromosomes 1 and 6 had Meta-QTL for number of nodules, nodule weight and specific nodule weight. Chromosome 7 had one for specific nodule weight. This study establishes the necessary groundwork for understanding the role that exotic germplasm can play for the breeding of better N fixation ability in the lentil crop

A new species of Tullbergia (Collembola, Tullbergiidae) from Buenos Aires, Argentina

A new species of Tullbergia from Argentina is described and illustrated; it is differentiated from Tullbergia paranensis by the number of vesicles of postantennal organ, pseudocelli shape and its formulae and the number of dorsal sensilla on Ant. IV. In addition a key for the identification of the members of the family from Argentina is included.Facultad de Ciencias Naturales y Muse

A new species of Tullbergia (Collembola, Tullbergiidae) from Buenos Aires, Argentina

A new species of Tullbergia from Argentina is described and illustrated; it is differentiated from Tullbergia paranensis by the number of vesicles of postantennal organ, pseudocelli shape and its formulae and the number of dorsal sensilla on Ant. IV. In addition a key for the identification of the members of the family from Argentina is included.Facultad de Ciencias Naturales y Muse

Type material of Protura (Hexapoda) housed at the collection of División Entomología of Museo de La Plata, Argentina

Los ejemplares tipo de Protura (Hexapoda) depositados en el Museo de La Plata (División Entomología) fueron examinados y listados. Para cada taxón, se brinda información actualizada y sus datos de recolección. Dichos ejemplares pertenecen a seis especies descriptas por las especialistas Julia Vidal Sarmiento y Judith Najt, entre 1970 y 1972. El material tipo incluye seis holotipos, dos alotipos y 17 paratipos. Setenta y cuatro especímenes en preparados microscópicos sin determinar son conservados en la colección general.Type specimens of Protura (Hexapoda) housed at the Museo de La Plata (División Entomología) were examined and listed. For each taxon the updated information and collection data are given. The material includes six species described by the specialists Julia Vidal Sarmiento and Judith Najt between 1970 and 1972. The type material consists on six holotypes, two allotypes and 17 paratype specimens. Seventy four undetermined specimen slides are retained in the general collection.Facultad de Ciencias Naturales y Muse

Evolutionary Heritage Influences Amazon Tree Ecology

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change

Evolutionary Heritage Influences Amazon Tree Ecology

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change

Globally invariant metabolism but density-diversity mismatch in springtails.

Soil life supports the functioning and biodiversity of terrestrial ecosystems. Springtails (Collembola) are among the most abundant soil arthropods regulating soil fertility and flow of energy through above- and belowground food webs. However, the global distribution of springtail diversity and density, and how these relate to energy fluxes remains unknown. Here, using a global dataset representing 2470 sites, we estimate the total soil springtail biomass at 27.5 megatons carbon, which is threefold higher than wild terrestrial vertebrates, and record peak densities up to 2 million individuals per square meter in the tundra. Despite a 20-fold biomass difference between the tundra and the tropics, springtail energy use (community metabolism) remains similar across the latitudinal gradient, owing to the changes in temperature with latitude. Neither springtail density nor community metabolism is predicted by local species richness, which is high in the tropics, but comparably high in some temperate forests and even tundra. Changes in springtail activity may emerge from latitudinal gradients in temperature, predation and resource limitation in soil communities. Contrasting relationships of biomass, diversity and activity of springtail communities with temperature suggest that climate warming will alter fundamental soil biodiversity metrics in different directions, potentially restructuring terrestrial food webs and affecting soil functioning

Global fine-resolution data on springtail abundance and community structure

Springtails (Collembola) inhabit soils from the Arctic to the Antarctic and comprise an estimated ~32% of all terrestrial arthropods on Earth. Here, we present a global, spatially-explicit database on springtail communities that includes 249,912 occurrences from 44,999 samples and 2,990 sites. These data are mainly raw sample-level records at the species level collected predominantly from private archives of the authors that were quality-controlled and taxonomically-standardised. Despite covering all continents, most of the sample-level data come from the European continent (82.5% of all samples) and represent four habitats: woodlands (57.4%), grasslands (14.0%), agrosystems (13.7%) and scrublands (9.0%). We included sampling by soil layers, and across seasons and years, representing temporal and spatial within-site variation in springtail communities. We also provided data use and sharing guidelines and R code to facilitate the use of the database by other researchers. This data paper describes a static version of the database at the publication date, but the database will be further expanded to include underrepresented regions and linked with trait data.</p

The global abundance of tree palms

Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests