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Deserts are subject to significant anthropogenic pressure. The capacity to buffer against changes in the local environment and biodiversity are critical for ecosystem functioning. Foundation species can be a solution to rapidly assess ecological function and provide a simple nature‐based solution to protect against continuing biodiversity losses. A foundation species is defined as a species that exerts and promotes a positive set of processes for the biotic network. Two different shrub species in the central drylands of California were used to assay a potential buffer for plant species richness and to examine the species‐specificity of foundation facilitation. A five‐year dataset in two distinct regions differing in aridity was used to test the hypothesis that the direct effects of foundation plants facilitate other plant species and buffer diversity losses to a changing climate. The predicted positive effects of both shrub species on species richness increased with increasing local temperatures sampled. Finally, projected temperature increases for the region in trained Bayesian models demonstrated that both shrub species can profoundly increase in their capacity to facilitate plant species richness. Colloquially, this positive ecological effect can be described as the patronus charm hypothesis because regardless of the form of the protector, shrub species provided a talisman against local loss of richness driven by temperature increases. [ABSTRACT FROM AUTHOR]

An assessment was carried out at Nuclear Technology Development Centre to evaluate the capacity of the plant species Epipremnum pinnatum to uptake, translocate and accumulate Th and U. The experiments were conducted under controlled conditions in a greenhouse, using cultivation in soil from uranium mine and cultivation in nutrient solution (hydroponic technique) using standards of the elements of interest. The plant species was analysed by Neutron Activation , k0 standardization method. The ANOVA test, R software and Tukey's correction were applied, the results of which showed that the candidate biomonitor plant presented good Th and U uptake in both experiments, indicating a preference for accumulate in the roots. [ABSTRACT FROM AUTHOR]

Current rates of climate change are exceeding the capacity of many plant species to track climate, thus leading communities to be in disequilibrium with climatic conditions. Plant canopies can contribute to this disequilibrium by buffering macro‐climatic conditions and sheltering poorly adapted species to the oncoming climate, particularly in their recruitment stages. Here we analyse differences in climatic disequilibrium between understorey and open ground woody plant recruits in 28 localities, covering more than 100,000 m2, across an elevation range embedding temperature and aridity gradients in the southern Iberian Peninsula. This study demonstrates higher climatic disequilibrium under canopies compared with open ground, supporting that plant canopies would affect future community climatic lags by allowing the recruitment of less arid‐adapted species in warm and dry conditions, but also it endorse that canopies could favour warm‐adapted species in extremely cold environments as mountain tops, thus pre‐adapting communities living in these habitats to climate change. [ABSTRACT FROM AUTHOR]

The purification effect of a natural wetland landscape is often low when the focus is placed on the landscape effect. The effective combination of constructed wetland technology with landscape construction is challenging. Taking the Yuhe Wetland Park in Datong, Shanxi Province, China, as an example, the COD, phosphorus, and nitrogen removal capacities of aquatic plant species were determined, as well as the effects of the soil and the microbial communities. The highest COD and P removal capacity was observed for Typha orientalis Presl. which the purification rate reached 76.9% and 76.6%, and the highest N removal capacities were found for Scirpus validus Vahl., the rate of purification was 83.4%. Gram-negative bacteria were dominant. [ABSTRACT FROM AUTHOR]

Exploration of the novel species of the genus Paenibacillus with plant-growth promoting characteristics at the low-temperature environment is of great significance for the development of psychrotolerant biofertilizer in forestry and agriculture. During the course of isolation of root endophytes of Larix gmelinii in the island frozen soil, three strains designated as T3-5-0-4, N1-5-1-14 and N5-1-1-5 were isolated. The three strains showed plant growth-promoting properties at the low temperature, such as phosphate solubilization, indole-3-acetic acid biosynthesis and siderophore production. According to pairwise sequence analyses of the 16S rRNA genes, the three strains represent putatively novel taxa within the genus Paenibacillus. The strains have typical chemotaxonomic characteristics of the genus Paenibacillus by having meso-diaminopimelic acid as diagnostic diamino acid, anteiso-C15:0 as the predominant fatty acid and MK-7 as the predominant menaquinone. The polar lipid profiles of all strains contained diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The sizes of the genomes of the stains ranged from 5.66 to 9.07 Mb and the associated G+C contents ranged from 37.9% to 44.7%. Polyphasic taxonomic study including determination of genome relatedness indices revealed that the strains are representatives of three novel species in the genus Paenibacillus. Consequently, isolates T3-5-0-4, N1-5-1-14 and N5-1-1-5 are proposed as novel species for which the names of Paenibacillus endoradicis sp. nov. (CFCC15691T = KCTC43441T), Paenibacillus radicibacter sp. nov, (CFCC15694T = KCTC43442T) and Paenibacillus radicis sp. nov. (CFCC15710T = KCTC43173T), respectively. Moreover, analysis for biosynthetic genes showed that the strains have potential for plant growth-promoting characteristics, plant rhizospheres colonization and low-temperature adaption, most of which are consistent with the results of the bioactivity test. [ABSTRACT FROM AUTHOR]

A plant's stress response involves the production of phytochemicals, including phenolic compounds. Their synthesis can be modulated by organic (ORG) or non-organic (NORG) farming systems in which they are grown. To examine this issue, thirteen plant-based foods cultivated in ORG and NORG systems were compared in terms of antioxidant capacity, total content of phenolics, anthocyanins, flavan-3-ols and flavonols. The results showed that NORG fruits tended to have higher phenolic compounds content, whereas ORG fruits had more antioxidant capacity. NORG legume stood out for having higher values from all the parameters analyzed in comparison to its ORG equivalent. ORG nuts showed more flavan-3-ols and flavonols than their NORG counterparts, nonetheless, tended to be less antioxidant. ORG vegetables displayed higher phenolics and anthocyanins, which reflected in higher antioxidant capacity than NORG ones. These findings suggest that farming systems differentially modulate phenolic compound composition and antioxidant capacity based on the plant species studied. [ABSTRACT FROM AUTHOR]

The humid tropics harbor great biological diversity, in addition to native species with forage potential as alternatives for animal feed. However, using trees and shrubs and having plantations are limited by the absence of information on their growth and seed germination. Therefore, the goal was to evaluate the germination capacity of native plant species with forage potential in tropical rainforest conditions, selecting eight species with important nutritional value: Bauhinia tarapotensis, Crescentia cujete, Zygia longifolia, Cecropia ficifolia, Piptocoma discolor, Piper bredemeyeri, Calathea lutea and Heliconia rostrata. Two treatments were evaluated: T1: Seeds (sexual and asexual) immersed for 12 hours in water, and T2: Seeds (sexual and asexual) without any pre-germination treatment (control). Significant differences were found in the germination percentage among species, treatments and the interaction of the two factors (p < 0.01). The species C. cujete, C. ficifolia and P. discolor presented better germination percentages with T1, in contrast to P. bredemeyeri, which adapted better to T2. In the same sense, H. rostrata (93%), C. cujete (91%) and Z. longifolia (89%) with T1, were the species with the highest germination capacity when compared to the other species, being desirable for use as fodder in agricultural production systems, due to their high germination power. In general, the pre-germinative treatment with water was very effective in increasing the permeability of the seed coat and, therefore, favored the breaking of endogenous physiological dormancy. [ABSTRACT FROM AUTHOR]

Climate warming is shifting the distributions of mountain plant species to higher elevations. Cold‐adapted plant species are under increasing pressure from novel competitors that are encroaching from lower elevations. Plant capacity to adjust to these pressures may be measurable as variation in trait values within a species. In particular, the strength and patterns of intraspecific trait variation along abiotic and biotic gradients can inform us whether and how species can adjust their anatomy and morphology to persist in a changing environment.Here, we tested whether species specialized to high elevations or with narrow elevational ranges show more conservative (i.e. less variable) trait responses across their elevational distribution, or in response to neighbours, than species from lower elevations or with wider elevational ranges. We did so by studying intraspecific trait variation of 66 species along 40 elevational gradients in four countries in both hemispheres. As an indication of potential neighbour interactions that could drive trait variation, we also analysed plant species' height ratio, its height relative to its nearest neighbour.Variation in alpine plant trait values over elevation differed depending on a species' median elevation and the breadth of its elevational range, with species with lower median elevations and larger elevational range sizes showing greater trait variation, i.e. a steeper slope in trait values, over their elevational distributions. These effects were evidenced by significant interactions between species' elevation and their elevational preference or range for several traits: vegetative height, generative height, specific leaf area and patch area. The height ratio of focal alpine species and their neighbours decreased in the lower part of their distribution because neighbours became relatively taller at lower elevations. In contrast, species with lower elevational optima maintained a similar height ratio with neighbours throughout their range.Synthesis. We provide evidence that species from lower elevations and those with larger range sizes show greater intraspecific trait variation, which may indicate a greater ability to respond to environmental changes. Also, larger trait variation of species from lower elevations may indicate stronger competitive ability of upslope shifting species, posing one further threat to species from higher ranges. [ABSTRACT FROM AUTHOR]

Decorative plants can efficiently purify formaldehyde and improve the quality of indoor air. The existing studies primarily revealed that the aerial and underground parts of plants' capacity to purify formaldehyde, while the performance of stems is unclear. A formaldehyde fumigation experiment was conducted on Epipremnum aureum and Rohdea japonica in a sealed chamber. Results showed the stems could remove formaldehyde. The efficiency of removal by the stems of each plant was 0.089 and 0.137 mg∙m−3∙h−1, respectively, the rate of purification was 40.0 and 61.6%, respectively. Both were related to plant species and the latter was affected by other factors like exposed area. To further explore the mechanism of phytoremediation, the correlation between the concentration of formaldehyde and CO2 during the experiment was investigated. Results showed when leaves of plants were exposed to formaldehyde, the concentration of CO2 increased with the decrease in concentration of formaldehyde, and the change in concentration of CO2 could be used as an indicator of the degree of decontamination of formaldehyde by the plants. [ABSTRACT FROM AUTHOR]

Aim: To examine calcicole and calcifuge plant strategies, as well as nutrient‐acquisition strategies, as drivers of the distribution of species in response to edaphic factors, and the degree to which these strategies may act as filters to species establishment in ecological restoration on heavily altered or reconstructed substrates. Location: An 82,000‐ha area within a major mining province in the Mid‐West region of Western Australia, harboring vegetation communities ranging from species‐poor halophytic scrub on saline flats to dense biodiverse shrubland on the skeletal soils of ancient Banded Ironstone Formations (BIF). Methods: Univariate and multivariate analyses were employed to examine how variation in soil chemistry and landscape position (undulating plains, slopes, and BIF crests and ridges) influenced patterns of floristic diversity, calcifuge plant strategies, and nutrient‐acquisition strategies in 538 plant species from 830 relevés. Results: Landscape position was the strongest driver of species richness and vegetation functional composition. Soils became increasingly acidic and P‐impoverished along an increasing elevational gradient. Vegetation from different landscape positions was not compositionally dissimilar, but vegetation of BIF crests and ridges was up to twice as biodiverse as vegetation from adjacent lower‐relief areas and harbored higher proportions of calcifuge species and species with mycorrhizal associations. Main conclusions: Topographic and edaphic complexity of BIF landforms in an otherwise relatively homogenous landscape has likely facilitated species accumulation over long time periods. They represent musea of regional floristic biodiversity, excluding only species that cannot establish or are inferior competitors in heavily weathered, acidic, skeletal, and nutrient‐impoverished soils. Plant strategies likely represent a major filter in establishing biodiverse, representative vegetation on postmining landforms in geologically ancient regions. [ABSTRACT FROM AUTHOR]

Pollinators can mediate facilitative or competitive relationships between plant species, but the relative importance of these two conflicting phenomena in shaping community‐wide pollinator resource use remains unexplored. This article examines the idea that the arrangement of large samples of plant species in Hutchinsonian pollinator niche space (n‐dimensional hypervolume whose axes represent pollinator types) can help to evaluate the comparative importance of facilitation and competition as drivers of pollinator resource use at the community level. Pollinator composition data were gathered for insect‐pollinated plants from the Sierra de Cazorla mountains (southeastern Spain), comprising ~95% of widely distributed insect‐pollinated species. The following questions were addressed at regional (45 sites, 221 plant species) and local (1 site, 73 plant species) spatial scales: (1) Do plant species clusters occur in pollinator niche space? Four pollinator niche spaces differing in dimensionality were considered, the axes of which were defined by insect orders, families, genera, and species. (2) If all plant species form a single, indivisible cluster, are they overdispersed or underdispersed within the cluster relative to a random arrangement? "Clusterability" tests failed to reject the null hypothesis that there was only one pollinator‐defined plant species cluster in pollinator niche space, irrespective of spatial scale, pollinator niche space, or pollinator importance measurement (proportions of pollinator individuals or flowers visited by each pollinator type). Observed means of interspecific dissimilarity in pollinator composition were smaller than randomly simulated values in the order‐, family‐, and genus‐defined pollinator niche spaces. This finding revealed an underdispersed arrangement of plant species in each of these pollinator niche spaces. In the undisturbed montane habitats studied, arrangement of insect‐pollinated plant species in the various niche spaces defined by pollinator composition did not support a major role for interspecific competition as a force shaping community‐wide pollinator resource use by plants, but rather suggested a situation closer to the facilitation‐dominated extreme in a hypothetical competition‐facilitation gradient. Results also highlight the importance of investigations on complete or nearly complete insect‐pollinated plant communities for suggesting and testing novel hypotheses on the ecology and evolution of plant–pollinator systems. [ABSTRACT FROM AUTHOR]

1. Host recognition and movement among plant species is widely studied in adult insects. These behaviours are rarely considered in juveniles despite evidence that they also move between plants. 2. This study investigated what may influence caterpillars of a generalist moth Helicoverpa punctigera to move among individual plants and whether caterpillars gravitate towards more vigorously flowering plants in the field. 3. This study tested caterpillar behaviour towards potted plants of a primary and secondary host species. The plants were inserted into the ground 50 cm apart. Caterpillars were placed, alone, onto either the primary or secondary host and left for 24 h before recording their final position. Individual caterpillars were also placed on the ground equidistant from each plant species, and their orientation behaviour was filmed. 4. Caterpillars placed on either a primary or secondary host plant for 24 h moved to the other plant species a quarter of the time. 5. They mostly moved to the primary host when placed at equal distance from each plant species and appeared to track volatiles by raising and swaying their heads. 6. In field surveys of two native daisy hosts at multiple field sites, the number of flower heads on each plant or stand was recorded along with the number of Helicoverpa larvae. Almost all caterpillars were on the primary host species, and 76% were on plants with more flower heads than the median. 7. This study concludes that H. punctigera caterpillars approach plants with attractive volatiles but wander from both attractive and less attractive plants (Restlessness hypothesis). They therefore gravitate towards vigorously flowering primary hosts. [ABSTRACT FROM AUTHOR]

Several studies have previously reported that nanomaterial uptake and toxicity in plants are species dependent. However, the differences between photosynthetic pathways, C3 and C4, following nanomaterial exposure are poorly understood. In the current work, wheat and rice, two C3 pathway species are compared to amaranth and maize, which utilize the C4 photosynthetic mechanism. These plants were cultured in soils which were spiked with CuO, Ag, TiO2, MWCNT, and FLG nanomaterials. Overall, the C4 plant exhibited higher resilience to NM stress than C3 plants. In particular, significant differences were observed in chlorophyll contents with rice returning a 40.9–54.2% decrease compared to 3.5–15.1% for maize. Fv/Fm levels were significantly reduced by up to 51% in rice whereas no significant reductions were observed in amaranth and maize. Furthermore, NM uptake in the C3 species was greater than that in C4 plants, a trend that was also seen in metal concentration. TEM results showed that CuO NPs altered the chloroplast thylakoid structure in rice leaves and a large number of CuO NPs were observed in the vascular sheath cells. In contrast, there were no significant changes in the chloroplasts in the vascular sheath and no significant CuO NPs were found in maize leaves. This study was the first to systematically characterize the effect of metal and carbon-based nanomaterials in soil on C3 and C4 plants, providing a new perspective for understanding the impact of nanomaterials on plants. [ABSTRACT FROM AUTHOR]

Summary: The endodermis surrounds and protects the vasculature partly by depositing hydrophobic suberin in the cell walls. Yet, some cells remain unsuberised. These historically termed 'passage cells' are assumed to provide a low‐resistance pathway to the xylem. Only recently have we started to gain molecular insights into these cells, which allow us to probe how roots coordinate communication with the environment across barriers with single‐cell precision. Increased understanding of root physiology at a high‐resolution is intriguing, as it is likely to provide us with new tools to improve overall plant health. With this in mind, we here provide a brief overview of passage cells, their presence across plant species, as well as a molecular update and future directions for passage cell‐related research. [ABSTRACT FROM AUTHOR]

Pre-emergent herbicides have been developed for their long residual effect; however, they can make sensitive successor cultures unfeasible. Waste remediation techniques are needed for sustainable agricultural systems; for this, the edaphoclimatic asymmetries in the country must be considered. This study aimed to evaluate the remedial capacity of the herbicide diclosulam by covering crops under different edaphoclimatic conditions. Treatments were arranged in an n × 2 factorial scheme, the first factor being the number of plant species in each location and the second being the presence or absence of diclosulam in the soil. The physiological and growth characteristics of 15 potential phytoremediation species were evaluated. Herbicide residues in the environment were positively correlated with the soil pH; organic matter, aluminum, and silt contents; and aluminum saturation. The effectiveness of phytoremediation varied between species and between regions. Plant species suitable for efficient phytoremidation systems of diclosulam residues were Canavalia ensiformis for Couto Magalhães de Minas, Cajanus cajan and Canavalia ensiformis for Diamantina, Raphanus sativus for Erechim and Cajanus cajan for São João Evangelista. [ABSTRACT FROM AUTHOR]

Remnants of native tallgrass prairie experience elevated atmospheric nitrogen (N) deposition in urban areas, with potential effects on species traits that are important for N cycling and species composition. We quantified bulk (primarily wet) inorganic N (NH4+-N + NO3--N) deposition at six sites along an urban development gradient (6–64% urban) in the Dallas-Fort Worth metropolitan area from April 2014 to October 2015. In addition, we conducted a phytometer experiment with two common native prairie bunchgrass species––one well studied (Schizachyrium scoparium) and one little studied (Nasella leucotricha)––to investigate ambient N deposition effects on plant biomass and tissue quality. Bulk inorganic N deposition ranged from 6.1–9.9 kg ha-1 yr-1, peaked in spring, and did not vary consistently with proportion of urban land within 10 km of the sites. Total (wet + dry) inorganic N deposition estimated using bulk deposition measured in this study and modeled dry deposition was 12.9–18.2 kg ha-1 yr-1. Although the two plant species studied differ in photosynthetic pathway, biomass, and tissue N, they exhibited a maximum 2-3-fold and 2-4-fold increase in total biomass and total plant N, respectively, with 1.6-fold higher bulk N deposition. In addition, our findings indicate that while native prairie grasses may exhibit a positive biomass response to increased N deposition up to ~18 kg ha-1 yr-1, total inorganic N deposition is well above the estimated critical load for herbaceous plant species richness in the tallgrass prairie of the Great Plains ecoregion and thus may negatively affect these plant communities. [ABSTRACT FROM AUTHOR]

Aims: Tidal marsh vegetation along estuaries is exposed to strong environmental gradients that determine which species — enabled through specific traits — can establish and persist. With these ecosystems under anthropogenic pressure, in-depth knowledge on the conservation of remaining tidal wetlands and restoration potentials is needed. In this study we elaborate the habitat conditions in the natural vegetation of the Elbe estuary and analyze: (a) which abiotic factors drive species composition; and (b) which species traits are key to the plants’ strategies in this specific ecotone. Location: Three sites in the Elbe estuary (river kilometer 671–703). Methods: We collected data on soil nutrients, inundation period and wave height and sampled traits of the 17 most abundant plant species, which we analyzed by RLQ (three-table analysis, including environment variables [R], species abundance [L] and a species traits table [Q]). Results: We detected a strong ˈwave–disturbance–inundation gradientˈ, which separated sparsely vegetated low-lying plots receiving high wave impact and exposed to long inundation periods, from high-lying plots showing dense vegetation and aerated soils. Close to the shore, plants showed low organ density and high investment into rhizomes, with a correlation of 0.72 between mass fraction of rhizome and phosphorus content of rhizome tissue. On higher elevations, plants strongly expressed traits relating to competition, like high allocation to stem biomass. Further, we found species with high leaf chlorophyll content showing low specific leaf area values and a negative correlation with the nutrient gradient. Conclusion: The results of our study are particularly relevant for restoration measures in order to re-establish healthy marsh vegetation. However, changes in the environmental conditions, for instance stronger wave energies by a higher shipping frequency in the river channel and sea level rise may trigger changes in species composition through plant trait adaptations, for example by demanding a stem flexibility beyond what would be structurally feasible. [ABSTRACT FROM AUTHOR]

Functional traits can determine pairwise species interactions, such as those between plants and pollinators. However, the effects of biogeography and evolutionary history on trait‐matching and trait‐mediated resource specialization remain poorly understood.We compiled a database of 93 mutualistic hummingbird–plant networks (including 181 hummingbird and 1,256 plant species), complemented by morphological measures of hummingbird bill and floral corolla length. We divided the hummingbirds into their principal clades and used knowledge on hummingbird biogeography to divide the networks into four biogeographical regions: Lowland South America, Andes, North & Central America, and the Caribbean islands. We then tested: (a) whether hummingbird clades and biogeographical regions differ in hummingbird bill length, corolla length of visited flowers and resource specialization, and (b) whether hummingbirds' bill length correlates with the corolla length of their food plants and with their level of resource specialization.Hummingbird clades dominated by long‐billed species generally visited longer flowers and were the most exclusive in their resource use. Bill and corolla length and the degree of resource specialization were similar across mainland regions, but the Caribbean islands had shorter flowers and hummingbirds with more generalized interaction niches. Bill and corolla length correlated in all regions and most clades, that is, trait‐matching was a recurrent phenomenon in hummingbird–plant associations. In contrast, bill length did not generally mediate resource specialization, as bill length was only weakly correlated with resource specialization within one hummingbird clade (Brilliants) and in the regions of Lowland South America and the Andes in which plants and hummingbirds have a long co‐evolutionary history. Supplementary analyses including bill curvature confirmed that bill morphology (length and curvature) does not in general predict resource specialization.These results demonstrate how biogeographical and evolutionary histories can modulate the effects of functional traits on species interactions, and that traits better predict functional groups of interaction partners (i.e. trait‐matching) than resource specialization. These findings reveal that functional traits have great potential, but also key limitations, as a tool for developing more mechanistic approaches in community ecology. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Trait‐based invasiveness studies typically categorize exotic species as invasive or noninvasive, implicitly assuming species form two homogenous groups. However, species can become invasive in different ways (e.g., high abundance, fast spread), likely relying on different functional traits to do so. As such, binary classification may obscure traits associated with invasiveness. We tested whether (1) the way in which invasiveness is quantified influences its correlation with functional traits and (2) different demography‐based metrics are related to different sets of traits. Using a case study of 251 herbs exotic to Victoria, Australia, we quantified species' invasiveness using 10 metrics: four continuous, demography‐based dimensions of invasiveness (spread rate, local abundance, geographic and environmental range sizes) and six binary classifications of invasiveness (based on alternative sources and invasion criteria). We examined the correlation between species' invasiveness and a set of four traits known to relate to plant demography and invasion. Then, we examined whether different demographic dimensions of invasiveness were better explained by different sets of traits. We found that the way invasiveness was quantified was important: different traits were linked with different invasiveness metrics, and some traits showed opposite effects across metrics. Species with fast spread were either tall with small seeds (i.e., good colonizers), or had heavy, animal‐dispersed seeds. Plants with a large environmental range had greater plasticity for some traits. Locally abundant plants had low SLA and heavy seeds (i.e., strong competitors). Animal dispersal was also key to reach a large geographic range. No traits were consistently related to the six binary classifications. Our results indicate that exotic plants are invasive in different ways and rely on different combinations of traits to be so. Some traits (e.g., seed mass) had complex relationships with invasion: they apparently promote, hampered, or had no influence on different dimensions of invasiveness. Our findings are consistent with the notion that plant species use strategies that may be near optimal under some, but not all, ecological conditions. Compared to binary classifications of invasiveness, the use of invasiveness dimensions advances clearer hypothesis testing in invasion science. [ABSTRACT FROM AUTHOR]

Specialization in mutualisms is thought to be a major driver of diversification, but few studies have explored how novel specialization evolves, or its relation to the evolution of other niche axes. A fundamental question is whether generalist interactions evolve to become more specialized (i.e., oscillation hypothesis) or if partner switches evolve without any change in niche breadth (i.e., musical chairs hypothesis). We examined alternative models for the evolution of specialization by estimating the mutualistic, climatic, and edaphic niche breadths of sister plant species, combining phylogenetic, environmental, and experimental data on Acmispon strigosus and Acmispon wrangelianus genotypes across their overlapping ranges in California. We found that specialization along all three niche axes was asymmetric across species, such that the species with broader climatic and edaphic niches, Acmispon strigosus, was also able to gain benefit from and invest in associating with a broader set of microbial mutualists. Our data are consistent with the oscillation model of specialization, and a parallel narrowing of the edaphic, climatic, and mutualistic dimensions of the host species niche. Our findings provide novel evidence that the evolution of specialization in mutualism is accompanied by specialization in other niche dimensions. [ABSTRACT FROM AUTHOR]

Premise: The distribution and even the survival of plant species are influenced by temperature. In an old climatically buffered infertile landscape (OCBIL) in Brazil, we previously characterized different strategies for foliar water uptake (FWU). It is possible that photosystem II tolerance to heat and excessive light intensity varies among species with different FWU capacities. Methods: The relationship between FWU, photoinhibition, and thermotolerance was investigated in seven species from this ecosystem. Results: The species with slow water absorption and high water absorption are those that presented less photoinhibition. Contrastingly, the species that have fast and low water absorption presented greater thermotolerance when their leaves are totally hydrated. However, when there is greater leaf dehydration, the most thermotolerant species were those with slow but high water absorption. Conclusions: Foliar water uptake is an important trait for plants to tolerate excessive light intensity and higher temperatures. Plants in this OCBIL may be differentially affected by future global warming, and the best strategy to deal with this expected climate change is with slow and high absorption of water. [ABSTRACT FROM AUTHOR]

Culturomic tools enable the exploration of trends in human–nature interactions, although they entail inherent biases and necessitate careful validation. Furthermore, people may engage with nature across different culturomic data sets differently. We evaluated people's digital interest and engagement with plant species based on Wikipedia and Google data and explored the conservation implications of these temporal interest patterns. As a case study, we explored the digital footprints of the most popular plant species in Israel. We analyzed 4 years of daily page views from Hebrew Wikipedia and 10 years of daily Google search volume in Israel. We modeled popularity of plant species in these 2 data sets based on a suite of plant attributes. We further explored the seasonal trends of people's interest in each species. We found differences in how people interacted digitally with plants in Wikipedia and Google. Overall, in Google, searches for species that have utility to humans were more common, whereas in Wikipedia, plants that serve as cultural emblems received more attention. Furthermore, in Google, popular species attracted more attention over time, opposite to the trend in Wikipedia. In Google, interest in species with short bloom duration exhibited more pronounced seasonal patterns, whereas in Wikipedia, seasonality of interest increased as bloom duration increased. Together, our results suggest that people's digital interactions with nature may be inherently different depending on the sources explored, which may affect use of this information for conservation. Although culturomics holds much promise, better understanding of its underpinnings is important when translating insights into conservation actions. Article impact statement: Comparing trends in plant popularity in Google and Wikipedia shows that people's engagement with nature differs across corpora. [ABSTRACT FROM AUTHOR]

The phenomenon of relapsing malaria has been recognised for centuries. It is caused in humans by the parasite species Plasmodium vivax and Plasmodium ovale , which can arrest growth at an early, asymptomatic stage as hypnozoites inside liver cells. These dormant parasites can remain quiescent for months or years, then reactivate causing symptomatic malaria. The dynamics of hypnozoite dormancy and reactivation are well documented but the molecular basis remains a complete mystery. Here, I observe that the process has striking parallels with plant vernalisation, whereby plants remain dormant through the winter before flowering in spring. Vernalisation is thoroughly studied in several plant species and its mechanisms are known in exquisite detail. Vernalisation may thus provide a useful framework for interrogating hypnozoite biology. Hypnozoites are dormant malaria parasites that can reactivate and cause relapses of malarial disease. They are an important factor in malaria biology and in the feasibility of malaria elimination programmes. The behaviour of Plasmodium hypnozoites has been documented clinically but the molecular-genetic basis of this behaviour is entirely unknown. Hypnozoites appear to have an intrinsic 'reactivation clock', encoded genetically or epigenetically, that is also sensitive to certain stimuli from the mammalian host. The hypnozoite 'clock' bears striking similarities to the phenomenon of vernalisation in flowering plants, which is well-characterised on a molecular-genetic level. The molecular biology of vernalisation can be used to build a conceptual model for the pathways that could underlie hypnozoite dormancy and reactivation. [ABSTRACT FROM AUTHOR]

Background: To address the need for easy and reliable species classification in plant genetic resources collections, we assessed the potential of five classifiers (Random Forest, Neighbour-Joining, 1-Nearest Neighbour, a conservative variety of 3-Nearest Neighbours and Naive Bayes) We investigated the effects of the number of accessions per species and misclassification rate on classification success, and validated theirs generic value results with three complete datasets. Results: We found the conservative variety of 3-Nearest Neighbours to be the most reliable classifier when varying species representation and misclassification rate. Through the analysis of the three complete datasets, this finding showed generic value. Additionally, we present various options for marker selection for classification taks such as these. Conclusions: Large-scale genomic data are increasingly being produced for genetic resources collections. These data are useful to address species classification issues regarding crop wild relatives, and improve genebank documentation. Implementation of a classification method that can improve the quality of bad datasets without gold standard training data is considered an innovative and efficient method to improve gene bank documentation. [ABSTRACT FROM AUTHOR]

This year marks the 100th anniversary of the experiments by Garner and Allard that showed that plants measure the duration of the night and day (the photoperiod) to time flowering. This discovery led to the identification of Flowering Locus T (FT) in Arabidopsis and Heading Date 3a (Hd3a) in rice as a mobile signal that promotes flowering in tissues distal to the site of cue perception. FT/Hd3a belong to the family of phosphatidylethanolamine-binding proteins (PEBPs). Collectively, these proteins control plant developmental transitions and plant architecture. Several excellent recent reviews have focused on the roles of PEBPs in diverse plant species; here we will primarily highlight recent advances that enhance our understanding of the mechanism of action of PEBPs and discuss critical open questions. [ABSTRACT FROM AUTHOR]

Iron bioavailability varies dramatically between soil types across the globe. This has given rise to high levels of natural variation in plant iron responses, allowing members of even a single species to thrive across a wide range of soil types. In recent years we have seen the use of genome-wide association analysis to identify natural variants underlying plant responses to changes in iron availability in both Arabidopsis and important crop species. These studies have provided insights into which genes have been important in shaping local adaptation to iron availability in different plant species and have allowed the discovery of novel regulators and mechanisms, not previously identified using mutagenesis approaches. Furthermore, these studies have allowed the identification of markers that can be used to accelerate breeding of future elite varieties with increased resilience to iron stress and improved nutritional quality. The studies highlighted here show that, in addition to studying plant responses to iron alone, it is important to consider these responses within the context of plant nutrition more broadly and to also consider iron regulation in relation to additional traits of agronomic importance such as yield and disease resistance. [ABSTRACT FROM AUTHOR]

The use of plant species to stabilize and accumulate trace elements in contaminated soils is considered of great usefulness given the difficulty of decontaminating large areas subjected to mining for long periods. In this work, the bioaccumulation of trace elements is studied by relating the concentrations in leaves and roots of three plants of Mediterranean distribution (Dittrichia viscosa, Cistus salviifolius, Euphorbia pithyusa subsp. cupanii) with the concentrations of trace elements in contaminated and uncontaminated soils. Furthermore, in the case of D. viscosa, to know the concentration of each element by biomass, the pool of trace elements was determined both in the aerial part and in the roots. The bioaccumulation factor was not high enough in any of the species studied to be considered as phytoextractors. However, species like the ones studied in this work that live on soils with a wide range of concentration of trace elements and that develop a considerable biomass could be considered for stabilization of contaminated soils. The plant species studied in this work are good candidates for gentle-remediation options in the polluted Mediterranean. [ABSTRACT FROM AUTHOR]

Ex situ conservation is widely used to protect wild plant species from extinction. However, it remains unclear how genetic variation of ex situ plant collections reflects diversity of wild source populations. We conducted a global meta‐analysis of the genetic representativeness of ex situ populations by comparing genetic diversity (i.e., AR, allelic richness; He, expected heterozygosity; PPB, percent polymorphic bands; and SWI, Shannon–Winner index), inbreeding coefficient (FIS), and genetic differentiation between ex situ plant collections and their wild source populations. Genetic diversity (i.e., He, PPB, and SWI) was significantly lower in ex situ populations than their wild source populations, whereas genetic differentiation between ex situ and wild populations (ex‐situ‐wild FST), but not that among ex situ populations, was significantly higher than among wild populations. Outcrossing species, but not those with mixed mating system, had significantly lower genetic diversity in ex situ populations and significantly higher ex‐situ‐wild FST. When the collection size for ex situ conservation was ≥30 or 50, PPB, He, and ex‐situ‐wild FST were not significantly different between ex situ and wild populations, indicating a relatively high genetic representativeness. Collecting from the entire natural distribution range and mixing collections from different sources could significantly increase the genetic representativeness of ex situ populations. Type of ex situ conservation (i.e., planting or seed bank) had no effect on genetic representativeness. The effect size of He decreased and the effect size of ex‐situ‐wild FST increased as the duration of ex situ conservation increased. Our results suggest that current ex situ plant collections do not effectively capture the genetic variation of wild populations. Low genetic representativeness of ex situ populations was caused by both initial incomplete sampling from wild populations and genetic erosion during ex situ conservation. We emphasize that it is necessary to employ more thorough sampling strategies in future collecting efforts and to add new individuals where needed. Article impact statement: Low genetic representativeness of living plant collections is a worldwide problem in ex situ conservation. [ABSTRACT FROM AUTHOR]

Premise of research. Rapid environmental changes have raised questions about the capacity of plant populations to adapt to novel conditions. Salinity is increasing in both urban and rural areas because of irrigation and road deicing salt. While adaptation to salinity is found in some plant species, salt impairs plant fitness for the vast majority. Breeding to enhance adaptation to salinity has proved difficult, suggesting barriers to adaptation. Methodology. In this project, we assessed the capacity for adaptation to soil salinity. We planted an experimental population of Chamaecrista fasciculata (partridge pea, Fabaceae) in both roadside and greenhouse conditions. We assessed lifetime fitness as a composite of germination, survival, and the number of flowers or fruits produced. We estimated additive genetic variance for fitness in each greenhouse salinity treatment using aster models. Pivotal results. Significant additive genetic variance for fitness was detected in the control treatment in the greenhouse, in the low-salinity treatment in the greenhouse, and in the roadside experimental plot. Gene-by-environment interactions were also significant. This gene-by-environment interaction is caused by both differences in genetic variation among environments and a change in the ranks of the families. In the control and low-salinity treatments in the greenhouse experiment, the relative ranks of fitness among the paternal families visually demonstrate the gene-by-environment interaction. Conclusions. The findings of the roadside experiment demonstrate that this population has the potential to adapt to a salinized environment. This research found a gene-by-environment interaction that may alter the fitness of various families over small geographic scales, such as those found in a roadside. Reducing deicing salt usage may improve the health and quality of roadside ecosystems by enhancing the potential of some species to adapt. [ABSTRACT FROM AUTHOR]

Aim: Numerous studies have assessed whether species niches are conserved in geographically separated regions. However, most of them were performed on invasive species, with the limitation that such species have likely not yet reached their potential distribution in the invaded region. Here we test the hypothesis of niche conservatism in the entire group of 25 amphitropical desert disjunct plant species, naturally distributed in North and South America but absent in the tropics. We also assessed the influence of ecological (intensity of biotic interactions) and species‐specific factors (dispersal ability and adaptation to stress) on species niche differentiation between the two continents. Location: North America and South America. Time period: Recent. Major taxa studied: Plants. Amphitropical desert disjunct species. Methods: Species' presence coordinates and five biologically relevant climatic variables were used to quantify niche differentiation of species between continents by means of principal component analysis. Then, structural equation modelling was performed to assess the influence on niche differentiation of proxies for intensity of biotic interactions (habitat net primary productivity), species dispersibility (dispersal mode and plant traits), and adaptation to stress (leaf size). Results: Niche shift was detected for 24 out of the 25 species, mostly towards cooler environments in South America (−2.5 °C average) with respect to North America. These niche shifts were best explained by the productivity of species' habitats, in particular by the displacement of species' niches away from the more productive and competitive environments of South America. Main conclusions: Niche shift seems to be the rule in amphitropical desert plants. Our findings highlight a previously undetected connection between amphitropical disjunct species and macroecological characteristics of the Americas. We show that prevalent environments differ between South and North America, and suggest that associated biotic contexts (mainly competition from widespread tropical and subtropical forests in South America) play a determinant role on species' distribution and niches. [ABSTRACT FROM AUTHOR]

O ne of the main metals explored in the world is copper (Cu), a native element, which is rarely found pure in nature. The mining and processing of copper generates environmental debates due to the generation of polluting agents in the areas of concentration, smelting and refining, in addition to the negative impacts imposed on the vegetation and topography of the mined area. The study aimed to investigate the initial morphometric performance of the white ipe (Tabebuia roseo-alba (Ridl.) Sandwith) in a substrate composed of copper mining tailings and increasing percentages of organic matter, evaluate its phytoremediator potential and the Dickson's Quality Index (IQD). The experimental design was the entirely randomized one. Morphometric data of the treatment were collected regarding height, stem diameter and number of leaves of the plant species where they were later submitted to statistical and IQD analysis, in addition to calculations related to the index and translocation factor of copper in the plant and its phytoextracting capacity. The phytomass compartmentalized in roots and aerial part was collected, placed in a drying oven, ground and sent to the laboratory for the proper evaluation of the copper metal in the compartments of the plant species, in addition to the chemical evaluation of the substrate. It was concluded that white ipe has the potential to phytostabilize the copper element coming from mining tailings, as well as achieving a satisfactory IQD in treatment composed of 90% of mining tailings and 10% of organic matter. [ABSTRACT FROM AUTHOR]

Questions: Are hedgerows efficient corridors for forest‐dwelling species within agricultural landscapes? Do time and space interact synergistically to enhance forest plant species accumulation in hedgerows (i.e. the species–time–area relationship)? Does the distribution profile of forest herbs along hedgerows differ between specialist and generalist species? Location: Agricultural landscapes in northern France. Methods: We assembled a chronosequence of 99 dated (1725–2008) hedgerows, which were surveyed for forest plant species and a number of local‐proximal descriptors. A subset of 29 hedgerows were further sampled for species occurrence data in 5‐m segments. We used generalized linear models to test the interaction between time (hedgerow age) and space on species richness. Space was characterized by both habitat size (hedgerow length, width and height) and spatial connectedness: i.e. whether a hedgerow is attached to a woodland and how much woodland habitat is available in the surroundings. We used generalized linear mixed‐effects models to test whether the probability of occurrence of forest herbs along hedgerows differ between specialists and generalists. Results: Hedgerow age and length interacted synergistically to increase forest plant species richness. Hedgerows attached to woodlands hosted systematically more species. Taller and wider hedgerows with a lower intensity of adjacent land uses hosted more forest plant species. Increasing the spatial connectedness of hedgerows had a positive effect on the probability of occurrence of dispersal‐limited forest specialists in the understorey, which was not the case for generalists. Conclusion: As predicted by the species–time–area relationship, ancient and long hedgerows attached to woodlands host more species and are more effective corridors. Creating new hedgerows to connect isolated woodlands can be a suitable strategy to restore functional connectivity, but it will be effective only in the longer term. The conservation of the most ancient hedgerows within intensively managed agricultural landscapes, especially those attached to ancient woodlands, should therefore be a priority. [ABSTRACT FROM AUTHOR]

Introduction: Plant identification applications for use on smartphones have been increasing in availability, accuracy, and utilization. We aimed to perform an introductory study to determine if a plant identification application (ID app) used on a smartphone could identify toxic plants, and to compare apps to determine which is most reliable. Methods: We compared three popular iPhone plant ID apps, PictureThis (PT), PlantSnap (PS), and Pl@ntNet (PN), used to identify 17 commonly encountered toxic plants. Apps were used to photograph the entire plant, leaves, and flowers of ≥ 10 different plants for each species. Two toxicologists performed plant identification with confirmation of identification performed by a botanist, and inter-researcher agreement was confirmed. For each plant species, scores for accuracy of app identification of leaves, flowers, and whole plant were combined to create an overall composite score used to compare accuracy of each app (95% C.I.). Results: PictureThis had the best performance with 10/17 (59% [36 to 78]) plant species identified 100% correctly, as opposed to 8/17 (47% [26 to 69]) for Pl@ntNet and 1/17 for PlantSnap (5.8% [1.1 to 27]). Conclusion: A plant identification app may be a useful tool to assist healthcare providers and the public in identifying toxic plants. [ABSTRACT FROM AUTHOR]

Plant movements are generally slow, but some plant species have evolved the ability to move very rapidly at speeds comparable to those of animals. Whereas movement in animals relies on the contraction machinery of muscles, many plant movements use turgor pressure as the primary driving force together with secondarily generated elastic forces. The movement of stomata is the best-characterized model system for studying turgor-driven movement, and many gene products responsible for this movement, especially those related to ion transport, have been identified. Similar gene products were recently shown to function in the daily sleep movements of pulvini, the motor organs for macroscopic leaf movements. However, it is difficult to explain the mechanisms behind rapid multicellular movements as a simple extension of the mechanisms used for unicellular or slow movements. For example, water transport through plant tissues imposes a limit on the speed of plant movements, which becomes more severe as the size of the moving part increases. Rapidly moving traps in carnivorous plants overcome this limitation with the aid of the mechanical behaviors of their three-dimensional structures. In addition to a mechanism for rapid deformation, rapid multicellular movements also require a molecular system for rapid cell-cell communication, along with a mechanosensing system that initiates the response. Electrical activities similar to animal action potentials are found in many plant species, representing promising candidates for the rapid cell–cell signaling behind rapid movements, but the molecular entities of these electrical signals remain obscure. Here we review the current understanding of rapid plant movements with the aim of encouraging further biological studies into this fascinating, challenging topic. [ABSTRACT FROM AUTHOR]

Tolerance and suppression are distinct components of competition among plants, and recognizing how they affect competitive outcomes is important for understanding the mechanisms and consequences of competition. We used simulations informed by experimental trials to ask whether tolerance or suppression of competitors was more important for the survival of native plants experiencing competition with an exotic invasive species. When competition was pairwise, tolerance and suppression contributed equally to competitive rank in simulations. However, when multiple native genotypes competed together against an invader, the ability to tolerate competition was up to 50 times more important than the ability to suppress the invader. In two‐competitor communities the chief advantage of suppressing competitors was a global decrease in their abundance, but this advantage did not exist in communities of multiple competitors – which is more representative of natural conditions – because decreased competitor abundance benefited all plants regardless of their competitive ability. We suggest that this concept is analogous to a 'demolition derby,' an automotive contest where participants attempt to have the last functional vehicle on the playing field. Because strong suppressors share the benefits of eliminating competitors with other remaining competitors, we propose that tolerance of competitors is more beneficial than suppression when competition occurs in a multiplayer scenario – in a demolition derby and in nature. This finding has implications for our understanding of how competition influences plant species coexistence, plant community structure and invasion outcomes. [ABSTRACT FROM AUTHOR]

Modern agriculture and plant breeding must continuously meet the high and increasingly growing requirements of consumers and recipients. In this context, one of the conditions for effective management of any farm is access to quick and efficient diagnostics of plant pathogens, the result of which, together with the assessment of experts, provide breeders with tools to effectively reduce the occurrence of plant diseases. This paper presents information about biodiversity and spectrum of endophytic and phytopathogenic bacterial species identified in plant samples delivered to the Plant Disease Clinic in 2013-2019. During the tests, using the Biolog Gen III system, the species affiliation of the majority of detected bacterial strains found in plant tissues as an endophyte and not causing disease symptoms on plants was determined. These data were compiled and compared with the number of found identifications for a given species and data on the pathogenicity of bacterial species towards plants. In this way, valuable information for the scientific community was obtained about the species composition of the bacterial microbiome of the crop plants studied by us, which were confronted with available literature data. In the study, special attention was paid to tomato, which is the plant most often supplied for testing in the Plant Disease Clinic due to its economic importance. [ABSTRACT FROM AUTHOR]

The vast majority of terrestrial plants exchange nutrients with fungal partners forming different mycorrhizal types. The minority of plants considered as non‐mycorrhizal, however, are not necessarily free of any fungi, but are frequently colonized by elusive fungal endophytes, such as dark septate endophytes (DSE) or fine root endophytes (FRE). While a functional role of FRE in the improvement of nutrient gain was recently elucidated, the function of DSE is still in discussion and was here addressed for 36 plant species belonging to the families Equisetaceae, Cypereaceae and Caryophyllaceae.Molecular and microscopic staining approaches were conducted to verify the presence of DSE in the investigated species. Stable isotope natural abundances of the elements carbon, nitrogen, hydrogen and oxygen and total nitrogen concentrations were analysed for the respective species of the target plant families and accompanying mycorrhizal and non‐mycorrhizal (Brassicaceae) plant species.Staining approaches confirmed the presence of DSE in all investigated species within the families Equisetaceae, Cyperaceae and Caryophyllaceae. A co‐colonization with Paris‐type arbuscular mycorrhiza (AM) was occasionally found by staining and molecular approaches in species of the Equisetaceae. Species of the Equisetaceae, Cyperaceae and Caryophyllaceae were significantly 15N‐enriched in comparison to accompanying plants. In addition, a significant 13C and 2H enrichment and increased total nitrogen concentrations were found for representatives of the Equisetaceae.The 15N enrichment found here for representatives of Equisetaceae, Cyperaceae and Caryophyllaceae provides evidence for a functional role of the ubiquitous DSE fungi. DSE fungi obviously provide access to 15N‐enriched soil organic compounds probably in exchange for organic carbon compounds from plant photosynthesis. As indicated by additional 13C and 2H enrichments, representatives of the Equisetaceae apparently gain simultaneously organic carbon compounds from their AM fungi of the Paris‐morphotype. Thus, species of the Equisetaceae have to be considered as partially, or in case of the achlorophyllous fertile Equisetum arvense, as fully mycoheterotrophic at least in some stages of their life cycle.So far, mostly underappreciated fungi classified as DSE are suggested to occupy an ecologically relevant role similar to mycorrhizae and the occurrence of simultaneous functions of DSE and AM fungi in Equisetaceae is proposed. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Sugar transporters called SWEETs are utilized by plants for a variety of functions. Invading pathogens utilize them for the supply of nutrition, thus rendering the host susceptible, as shown in several plant species. Therefore, naturally occurring and genetically manipulated SWEET gene variants are being deployed for the development of resistant crop cultivars. [ABSTRACT FROM AUTHOR]

In the study of factors shaping species' poleward range boundaries, climatic constraints are often assigned greater importance than biotic interactions such as competition. However, theory suggests competition can truncate a species' fundamental niche in harsh environments. We test this by challenging a mechanistic niche model – containing explicit competition terms – to predict the poleward range boundaries of two globally distributed, ecologically similar aquatic plant species. Mechanistic competition models accurately predicted the northern range limits of our study species, outperforming competition‐free mechanistic models and matching the predictive ability of statistical niche models fit to occurrence records. Using the framework of modern coexistence theory, we found that relative nonlinearity in competitors' responses to temperature fluctuations maintains their coexistence boundary, highlighting the importance of this fluctuation‐dependent mechanism. Our results support a more nuanced, interactive role of climate and competition in determining range boundaries, and illustrate a practical, process‐based approach to understanding the determinants of range limits. [ABSTRACT FROM AUTHOR]

Facilitation by nurse plants likely increases from outside the canopy to the center of the canopy as stresses decrease towards the center of the canopy. These stress gradients may be important in controlling plant distributions, with stress-tolerant species specializing outside the canopy or at the canopy edge, and stress intolerant species specializing at the center of the canopy. We tested if interactions with nurse plants control the distribution of understory species, and if plants species specializing in the understory environment experience higher physiological stress when grown outside the canopy than species specializing in the open environments. We tested these predictions in field sites in the arid environment of Saudi Arabia. We measured the environmental conditions, understory species abundance, and functional and physiological traits of species found under nurse plant Acacia gerrardii. We found that Acacia trees have an overall facilitative impact on the understory species. Species found more commonly under nurse tree canopies experience significant physiological stress when growing outside canopies. In contrast, species found more commonly outside canopies do not experience significant physiological stress when growing either under canopies or outside canopies. Our results demonstrate that differences in species ability to tolerate environmental stresses are important in structuring herbaceous plant communities under nurse plants in these extremely stressful environments. [ABSTRACT FROM AUTHOR]

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The flora of the Thracian Lowland region was analyzed in 13 target localities (seminatural grasslands) near rapeseed fields for a 3-year period. A total of 245 flowering species were registered in the experimental fields, 178 of them were enthomophyllic plant species. Eleven adventitious and invasive species were recorded in representative experimental fields and their margin. The share of adventive species are small percent of the species composition, but pose a future threat to biodiversity. Maintaining the relative naturalness of these areas has a big role in the nutrition for the pollinators. This study provides data about the identification, observation in the field margins. The collected data could be a base for evaluation of the ecosystem services provided by agrocoenoses and neighboring semi-natural grasslands in the Thracian Lowland. [ABSTRACT FROM AUTHOR]

Studies were conducted from 2015 to 2018 to evaluate spotted lanternfly (SLF) distribution and developmental suitability of different plant species in the U.S. Tree bands on 283 trees spanning 33 species captured 21,006 SLF in 2 yr. More SLF per tree were trapped on tree-of-heaven Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae) than on other species, on average, and most adults were captured on tree-of-heaven. Frequency of detection of adult SLF was higher on tree-of-heaven than on other species but was actually equal or lower on tree-of-heaven than on all other species combined for younger SLF stages in 2015. An enclosed choice test between tree-of-heaven and black walnut Juglans nigra L. (Fagales: Juglandaceae) revealed nymphs showed little consistent preference, whereas adults consistently and significantly preferred tree-of-heaven. No-choice field sleeve studies evaluated SLF survivorship on 26 host plant species in 17 families. Ten plant species supported SLF for an average of ≥45 d, with the rest unable to support SLF for >30 d. Eight species were able to support development from first instar to adult: black walnut, chinaberry Melia azedarach L. (Sapindales: Meliaceae), oriental bittersweet Celastrus orbiculatus Thunb. (Celastrales: Celastraceae), tree-of-heaven, hops Humulus lupulus L. (Rosales: Cannabaceae), sawtooth oak Quercus acutissima Carruthers (Fagales: Fagaceae), butternut Juglans cinerea L, and tulip tree Liriodendron tulipifiera L. (Magnoliales: Magnoliaceae). The ability of SLF to develop to adult on hosts other than tree-of-heaven may impact pest management decisions. [ABSTRACT FROM AUTHOR]

With fast-evolving next-generation sequencing technology, a great amount of plant genome and transcriptome data are becoming available. Due to the availability of mature microRNA (miRNA) sequence information from the miRBase (release 21) database, it is possible to predict endogenous target mimics (eTMs) in plant by searching seed-matched target sites. We identified a total of 2669 non-redundant eTM records in 43 plant species to create a specialized web-based database platform. The platform is named PendoTMBase, which can provide details of the eTMs. Predicted pairing structure between eTMs and their target miRNA, expression levels of eTMs pairs and associated GO annotations are also stored in the database. With evaluations performed in silico, we have found that the eTMs are representative and fit for genetic studies and high value-added plants breeding. The platform also provides a function of predicting novel eTMs based on the miRNA sequences submitted by users. [ABSTRACT FROM AUTHOR]

In order to detect the effects of fertilization and mowing on stoichiometry characteristics of four plant species in an semi-arid steppe in Inner Mongolia. Four plant species including Artemisia frigida, Potentilla tanacetifolia, Aneurotepidimu chinemis, and Melissitus ruthenica in the steppe were collected in August 2014. Contents of carbon, nitrogen and phosphorus, and ratios of C : N and N : P in different plants in field experiment under nitrogen fertilization and mowing treatments were investigated. The effects of nitrogen fertilization and mowing on carbon, nitrogen and phosphorus, and ratios of C : N and N : P were analyzed with ANOV As. The differences of stoichiometry characteristics under different treatments were analyzed with Post-Hoc tests. The results wer'e as follows: Neither nitrogen fertilization nor mowing allowed carbon content in the steppe. Nitrogen fertilization significantly devated the plant nitrogen content (P<0.05), thus decreased the C: N ratio (P<0.05) and increased the N : P ratio (P<0.05). Mowing increased the nitrogen content of Melissitus ruthenica by 0.18% ( P<0.05), decreased the nitrogen content of Aneurotepidimu chinensis by 0.13% (P<0.05), but did not affect the nitrogen content of Aartemisia frigida or Potentilla tanacetifolia. Mowing significantly devaled the phosphorus contents of Artemisia frigida and Potentilla tanacetifolia ( P < 0. 05), but did not affect the phosphorus content of Melissitus ruthenica or Aneruotepidimu chinensis. The study has approved that nitrogen fertilization and mowing can affect the plant stoichiomtry characteristics in the steppe, but the affect varied with species. The results provide data support for the study on plant functional trails in the grassland. [ABSTRACT FROM AUTHOR]

To determine the effect of rivers, environmental conditions, and isolation by distance on the distribution of species in Amazonia. Location: Brazilian Amazonia. Time period: Current. Major taxa studied: Birds, fishes, bats, ants, termites, butterflies, ferns + lycophytes, gingers and palms. We compiled a unique dataset of biotic and abiotic information from 822 plots spread over the Brazilian Amazon. We evaluated the effects of environment, geographic distance and dispersal barriers (rivers) on assemblage composition of animal and plant taxa using multivariate techniques and distance- and raw-data-based regression approaches. Environmental variables (soil/water), geographic distance, and rivers were associated with the distribution of most taxa. The wide and relatively old Amazon River tended to determine differences in community composition for most biological groups. Despite this association, environment and geographic distance were generally more important than rivers in explaining the changes in species composition. The results from multi-taxa comparisons suggest that variation in community composition in Amazonia reflects both dispersal limitation (isolation by distance or by large rivers) and the adaptation of species to local environmental conditions. Larger and older river barriers influenced the distribution of species. However, in general this effect is weaker than the effects of environmental gradients or geographical distance at broad scales in Amazonia, but the relative importance of each of these processes varies among biological groups. [ABSTRACT FROM AUTHOR]

Aerial drones are providing a new source of high‐resolution imagery for mapping of plant species of interest, amongst other applications. On‐board detection algorithms could open the door to allow for applications in which drones can intelligently interact with their environment. However, the majority of plant detection studies have focused on detection in post‐flight processed orthomosaics. Greater research into developing detection algorithms robust to real‐world variations in environmental conditions is necessary, such that they are suitable for deployment in the field under variable conditions.We outline the steps necessary to develop such a system, show by example how real‐world considerations can be addressed during model training and briefly illustrate the performance of our best performing model in the field when integrated with an aerial drone.Our results show that introducing variations in brightness as an additional augmentation strategy during training is beneficial when dealing with real‐life data. We achieved a 27% improvement in the F1‐score obtained on the unseen test set when using this approach. Further improvements to the model performance were obtained through the use of weight map‐based loss, accounting for uncertainty in the annotation masks due to the indistinct nature of the edges of the target plants using weighting. This resulted in a 15% improvement in precision for the best configuration of hyper‐parameters, yielding a final model with an F1‐score of 83% and accuracy of 96%. Finally, results computed on the fly show that such a system is deployable in the field.This study shows that it is possible for a commercially available drone, integrated with a deep learning model, to detect invasive plants in the field and demonstrates methodology which could be applied to developing similar systems for other plant species of interest. The ability to perform detection on the fly is necessary for future applications in which intelligent interaction between a drone and its environment is required. [ABSTRACT FROM AUTHOR]

Allelopathic potential of Thymus pulegioides L. chemical polymorphism was investigated under natural and laboratory conditions. A field analysis of 127 natural habitats hosting chemotypes of T. pulegioides with different ratios of phenolics, geraniol, and ɑ-terpinyl acetate was conducted. Effects of chemotypes, and their main compounds on seed germination and radicle growth of Trifolium pratense L. and Poa pratensis L. were conducted under laboratory conditions. Field analysis showed that Poa species were more plentiful in comparison with Trifolium species, independent of the chemotypical composition of T. pulegioides habitats. Laboratory tests with plant-acceptors showed a stronger inhibitory effect of essential oils on the germination and radicle growth of P. pratensis but in some instances germination was stimulated. Dissimilar effects were observed for the same allelochemical through air and water on the same plant-acceptor. Significantly, different effects of essential oils on radicle growth occurred in T. pratense and P. pratensis: with sensitivity to the phenolic chemotype via air and the ɑ-terpinyl acetate chemotype through water. This demonstrates that chemical polymorphism can expand communication opportunities of T. pulegioides with associated plant species. Combining investigations in natural habitats with laboratory experiments can help understand the effect of chemical polymorphism on plant-plant ecological interactions. [ABSTRACT FROM AUTHOR]

Questions: The biodiversity of deserts is becoming increasingly threatened due to global change including the introduction of invasive species. Desert shrubs are foundational species that can facilitate native plant communities but can also benefit exotic species. The influence of exotic plants on the establishment of benefactors from seeds or seedlings is a critical knowledge gap. We tested if the establishment, survival, or growth of seedlings for a benefactor shrub species in California was reduced by the invasive grasses that they facilitate in the field. Location: San Joaquin Desert, California, USA. Methods: We conducted a field survey to determine if a native shrub, Ephedra californica, facilitated the invasive grass Bromus madritensis. Using seed collected from the field, we conducted a competition experiment on Ephedra californica, using a densities series of Bromus madritensis and under manipulated conditions of light, water, and simulated herbivory. We measured seedling establishment, survival, and biomass of Ephedra californica and Bromus madritensis. Results: In the field, Ephedra californica facilitated Bromus madritensiswithin the shrub canopy. In the competition experiment, Bromus madritensishad consistent negative effects on Ephedra californica emergence and seedling survival at all resource and herbivory levels. The emergence and survival of Ephedra californica was reduced in low light, but none of the manipulated conditions increased the competitive effect of Bromus madritensis. Conclusions: Reciprocal costs of facilitation by shrubs were evident in emergence and seedling survival but not in growth once established. Water, herbivory, and shade did not mitigate these costs, but also did not exacerbate competition from exotics. Direct competition with exotic plant species is the most significant impact tested here on dryland shrub species and manipulations of resources or herbivory may not effectively promote shrub recruitment. Native shrubs are well adapted to variable desert conditions and could be effective foundational species if invasive grasses are reduced. [ABSTRACT FROM AUTHOR]