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Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960’s, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs. Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.

Endophytic fungi live inside plant tissues and increase their resistance to abiotic and biotic factors. Our work is concerned with interannual variations of mycoendophyte diversity of leaves of Pistacia atlantica Desf. of dayate Aiat, in the region of Laghouat (Algeria) and this for the spring of 2013 and 2016. The morphological identification revealed the presence of 26 fungal genera. The difference in diversity is very significant between the two years of sampling, according to calculated Shannon Weaver indices. Based on principal component analysis, the distribution of these leaf microorganisms is influenced by the climatic conditions of the study area. Aspergillus and Epicoccum are dominant for 2013. In 2016, Aspergillus and Cladosporium dominate. The persistence of Aspergillus gives it an important role in the fight against the stress suffered by the leaf of Pistacia atlantica.

Foraging and feeding are indispensable for survival and their timing depends not only on the metabolic state of the animal but also on the availability of food resources in their environment. Since both these aspects are subject to change over time, these behaviours exhibit rhythmicity in occurrence. As the locomotor activity of an organism is related to its disposition to acquire food, and peak feeding in fruit flies has been shown to occur at a particular time of the day, we asked if cyclic food availability can entrain their rhythmic activity. By subjecting flies to cyclic food availability i.e., feeding/starvation (FS) cycles, we provided food cues contrasting to the preferred activity times and observed if this imposed cycling in food availability could entrain the activity/rest rhythm. We found that phase control, which is a property integral to entrainment, was not achieved despite increasing starvation duration of FS cycles (FS12:12, FS10:14 and FS8:16). We also found that flies subjected to T21 and T26 FS cycles were unable to match period of the activity rhythm to short or long T-cycles. Taken together these results show that external food availability cycles do not entrain the activity/rest rhythm of fruit flies. However, we find that starvation induced hyperactivity causes masking which results in phase changes. Additionally, T-cycle experiments resulted in minor period changes during FS treatment. These findings highlight that food cyclicity by itself may not be a potent zeitgeber but may act in unison with other abiotic factors like light and temperature to help flies time their activity appropriately.

Cuscuta campestris Yunck. is a stem holoparasitic flowering plant, wide-spread and currently considered invasive worldwide. It has both ecological and agricultural significance. However, little is known on how the conditions of the environment, and abiotic stresses in particular, could affect the success of this parasite. A total of 22 potential host plants, belonging to 10 species and 4 families, were tested as C. campestris hosts under different saline regimes. The changes in survival rate (number of successful infections) and growth (as cm day−1) of the parasite were studied. Salinity did significantly change the survival and growth rate of C. campestris, which effect was species- and cultivar-dependent. While generally the survival of the parasite decreased with increasing salinization, the opposite effect was observed on several host plants. However, survival rate did not always coincide with higher growth rate. This suggests that salinity produces different effects on the parasite depending on the host plant and these depend strongly not only on the species, but also on the cultivar. These results strongly suggest that under salt stress the suitability of various crop plants as hosts for C. campestris may change significantly, thus affecting the overall success of the parasite. In the light of the increased salinization of soils, this may have a significant effect on the spread of C. campestris and its agricultural impact.

Anuran richness patterns are strongly influenced by environmental factors. However, investigations on this issue have focused on the influence of abiotic factors without considering the joint effect of many existing variables, including the data sampling methodology and human demography. In this study we investigated the relationship between 21 environmental variables and anuran richness in brazilian biomes. Environmental variables represent a combination of human demographics, topographic, climatic and vegetation characteristics, and data sampling methodologies. We used principal component factorization and regressive and autoregressive models to select the most relevant variables for explaining anuran richness. Richness was correlated with demographic density, vegetation, accumulated rainfall, accumulated rainfall in the third and fourth quarter of the year, and accumulated rainfall in the first and second half of the year. However, the regressive and autoregressive models showed that human demographic density, sampling time, and sampling methodology were the best predictors of anuran richness. Our results highlight the importance of considering the effects of the human footprint and the methodology used for data collection on anuran species richness.

Chillies and chilli-based products are important spices on a global basis. The production, processing, transport and storage phases of chillies are prone to infection by Aspergillus Section Flavi and contamination with aflatoxins (AFs), especially aflatoxin B1 (AFB1) for which legislative limits exist in many countries. We have examined the effect of the interacting abiotic factors of water availability (water activity, aw; 0.995-0.850 aw) and temperature (15-37 °C) on (a) lag phases prior to growth, (b) growth, (c) AFB1 production and (d) contour maps of optimum and boundary conditions for colonisation and toxin production by three Aspergillus flavus strains on a 10% chilli-based medium. Additional studies with whole red chillies + A. flavus conidial inoculum on AFB1 contamination during storage for 10-20 days at 30 °C were also carried out. In vitro, the lag phases before growth were delayed by lower temperatures (15, 20 °C) and aw levels (0.928-0.901 aw). There was no statistical difference in growth between the three strains. Optimal growth was at 37 °C and 0.982 aw with no growth at 0.85 aw. Optimal temperature × aw conditions for AFB1 production were at 30 °C and 0.982 aw with no statistical difference in production between strains. No AFB1 was produced at 15-20 °C at 0.901 and 0.928 aw levels, respectively. In situ studies with A. flavus inoculated whole red chillies at 0.90 and 0.95 aw found that this species became the major component of the total fungal populations at 30 °C after 10-20 days storage. AFB1 contamination was above the European legislative limits (5 μg/kg) for spices at 0.90 aw after 20 days storage and at 0.95 aw after 10 and 20 days. This suggests that storage conditions of ≥0.90 aw, especially at ≥25-30 °C represents a significant risk of contamination with AFB1 at levels where rejection might occur, even after only 10-20 days storage.

This study sought to clarify whether suspended particles containing high Cu concentrations are present in the sea-surface microlayer (S-SML). For this reason, suspended particles (10–2000 μm) in the S-SML were collected periodically from a ship mooring pond during 2018–2020, and the acid-soluble Cu concentration in the suspended particles was measured as particulate Cu (P-Cu). The highest concentration of P-Cu in the S-SML of the pond was 75 μg L−1 with a 90th percentile value of 2.5 μg L−1. This is below P-Cu values reported for the S-SML in North American ports, but 140 times higher than this found in bulk seawater in the Atlantic Ocean. The highest P-Cu concentration in the S-SML of non-organism (abiotic) origin was 17 μg L−1, and the abiotic P-Cu to P-Cu ratio varied from 0.2 to 100%, likely depending on the quality and quantity of biogenic material in the S-SML samples. It is assumed that the S-SML particles examined here contain high Cu concentrations originating from ship antifouling paints.

Globodera rostochiensis and G. pallida are some of the most successful and highly specialized plant parasitic nematodes and among the most regulated quarantine pests globally. In Switzerland, they have been monitored by annual surveys since their first detection in Swiss soil in 1958. The dataset created was reviewed to produce an overview of the development and actual status of potato cyst nematodes (PCNs) in Switzerland. Positive fields represent 0.2% of all the samples analyzed, and their distribution is limited to central-west and western Switzerland, suggesting that new introduction of PCNs and the spread of the initial introduced PCN populations did not occur. In this way, the integrated management used in Switzerland appears to be effective. However, the increasing availability of potato varieties with resistance to G. rostochiensis and the limited availability of varieties with resistance to G. pallida, together with other biotic and abiotic factors, have promoted changes in the dominance of either species. Consequently, an extended monitoring program is of interest to Swiss farmers, to avoid favoring virulent traits that could be present in Swiss Globodera populations.

Most plant fungal pathogens that cause worldwide crop losses are understudied, due to various technical challenges. With the increasing availability of sequenced whole genomes of these non-model fungi, effective genetic analysis methods are highly desirable. Here, we describe a newly developed pipeline, which combines forward genetic screening with high-throughput next-generation sequencing to enable quick gene discovery. We applied this pipeline in the notorious soilborne phytopathogen Sclerotinia sclerotiorum and identified 32 mutants with various developmental and growth deficiencies. Detailed molecular studies of three melanization-deficient mutants provide a proof of concept for the effectiveness of our method. A master transcription factor was found to regulate melanization of sclerotia through the DHN (1,8-dihydroxynaphthalene) melanin biosynthesis pathway. In addition, these mutants revealed that sclerotial melanization is important for sclerotia survival under abiotic stresses, sclerotial surface structure, and sexual reproduction. Foreseeably, this pipeline can be applied to facilitate efficient in-depth studies of other non-model fungal species in the future. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

Stomata play a central role in plant responses to abiotic and biotic stresses. Existing knowledge regarding the roles of stomata in plant stress is centered on abiotic stresses and plant-pathogen interactions, but how stomata influence plant-herbivore interactions remains largely unclear. Here, we summarize the functions of stomata in plant-insect interactions and highlight recent discoveries of how herbivores manipulate plant stomata. Because stomata are linked to interrelated physiological processes in plants, herbivory-induced changes in stomatal dynamics might have cellular, organismic, and/or even community-level impacts. We summarize our current understanding of how stomata mediate plant responses to herbivory and environmental stimuli, propose how herbivores may influence these responses, and identify key knowledge gaps in plant-herbivore interactions.

The cucurbitaceae family comprises of economically important vegetable crops grown for food and medicine. Most cucurbit crops produce cucurbitacins in leaves, flowers, fruit, seed and roots which possess various pharmacological and pharmaceutical values. Cucurbitacins are toxic to pests and diseases, and allelopathic to noxious weeds thus providing opportunities for improving tolerance to biotic stresses. Further, cucurbitacins are responsive to environmental stimuli and can therefore enhance tolerance to abiotic stress. The objective of this review was to highlight the breeding value of cucurbitacins to develop cucurbitacins-enriched genotypes for food and medicine, and for management of biotic and abiotic stresses. The following themes were discussed: a comparative analysis of cucurbitacin concentrations in edible and non-edible plant parts; genetic control and associated quantitative trait loci and molecular markers associated with cucurbitacins; pharmacological and pharmaceutical values of cucurbitacins, and potential applications for management of biotic and abiotic stresses. Results of the present study will guide genetic improvement of cucurbitacins for use as food and medicine, and in the development of genotypes tolerant to biotic and abiotic stresses.

The objective of this study was to evaluate the potential intra-species variability of 3 Fusarium langsethiae strains in response to extreme climate change (CC) conditions on an oat-based matrix. The impact of elevated temperature (25 vs 30-34 °C) coupled with increasing drought stress (0.98 vs 0.95 aw) and elevated CO2 (400 vs 1000 ppm) were examined on lag phases prior to growth, growth rate, and production of the mycotoxins T-2 and HT-2 and their ratio. In comparison to the control conditions (25 °C; 0.98; 400 ppm), exposure to increased temperature (30-34 °C), showed similar reductions in the lag phase and fungal growth rates of all 3 strains. However, with elevated CO2 a reduction in both lag phases prior to growth and growth rate occurred regardless of the aw examined. For T-2 and HT-2 mycotoxin production, T-2 showed the most intra-species variability in response to the interacting abiotic stress factors, with the 3 strains having different environmental conditions for triggering increases in T-2 production: Strain 1 produced higher T-2 toxin at 25 °C, while Strain 2 and the type strain (Fl201059) produced most at 0.98 aw/30 °C. Only Strain 2 showed a reduction in toxin production when exposed to elevated CO2. HT-2 production was higher at 25 °C for the type strain and higher at 30-34 °C for the other two strains, regardless of the aw or CO2 level examined. The HT-2/T-2 ratio showed no significant differences due to the imposed interacting CC abiotic conditions.

The plant faces different pedological and climatic challenges that influence its growth and enhancement. While, plant-microbes interactions throught the rhizosphere offer several privileges to this hotspot in the service of plant, by attracting multi-beneficial mutualistic and symbiotic microorganisms as plant growth-promoting bacteria (PGPB), archaea, mycorrhizal fungi, endophytic fungi, and others…). Currently, numerous investigations showed the beneficial effects of these microbes on growth and plant health. Indeed, rhizospheric microorganisms offer to host plants the essential assimilable nutrients, stimulate the growth and development of host plants, and induce antibiotics production. They also attributed to host plants numerous phenotypes involved in the increase the resistance to abiotic and biotic stresses. The investigations and the studies on the rhizosphere can offer a way to find a biological and sustainable solution to confront these environmental problems. Therefore, the interactions between microbes and plants may lead to interesting biotechnological applications on plant improvement and the adaptation in different climates to obtain a biological sustainable agricultures without the use of chemical fertilizers.

Multiple viral infection is an important issue in health and agriculture with strong impacts on society and the economy. Several investigations have dealt with the population dynamics of viruses with different dynamic properties, focusing on strain competition during multiple infections and the effects on viruses’ hosts. Recent interest has been on how multiple infections respond to abiotic factors such as temperature (T). This is especially important in the case of plant pathogens, whose dynamics could be affected significantly by global warming. However, few mathematical models incorporate the effect of T on parasite fitness, especially in mixed infections. Here, we investigate simple mathematical models incorporating thermal reaction norms (TRNs), which allow for quantitative analysis. A logistic model is considered for single infections, which is extended to a Lotka-Volterra competition model for mixed infections. The dynamics of these two models are investigated, focusing on the roles of T-dependent replication and competitive interactions in both transient and asymptotic dynamics. We determine the scenarios of co-existence and competitive exclusion, which are separated by a transcritical bifurcation. To illustrate the applicability of these models, we ran single- and mixed-infection experiments in plants growing at 20º C and 30º C using two strains of the plant RNA virus Pepino mosaic virus. Using a macroevolutionary algorithm, we fitted the models to the data by estimating the TRNs for both strains in single infections. Then, we used these TRNs to feed the mixed-infection model estimating the strength of competition. We found an asymmetrical pattern in which each strain dominated at different T values due to differences in their TRNs. We also identified that T can modify competition interference greatly for both isolates. The models proposed here can be useful for investigating the outcomes of multiple-infection dynamics under abiotic changes and have implications for the understanding of viral responses to global warming., J.S. has been partially funded by the CERCA Program of the Generalitat de Catalunya, by the Ministry of Economy, Industry and Competitiveness (MINECO) grant MTM2015-71509-C2-1-R, by Agencia Estatal de Investigación (AEI) grant RTI2018-098322-B-I00, and by a Ramón y Cajal contract (RYC-2017-22243). C.A. was funded by the MINECO within a PhD program grant (FPU16/02569). This work was also supported by the AEI-FEDER grants AGL2014-59556-R and AGL2017-89550-R to P.G. and PID2019-103998GB-I00 to S.F.E.

The delivery of excessive fine sediment (particles < 2 mm in diameter) to rivers can cause serious deleterious effects to aquatic ecosystems and is widely acknowledged to be one of the leading contributors to the degradation of rivers globally. Despite advances in using biological methods as a proxy, physical measures remain an important method through which fine sediment can be quantified. The aim of this study was to provide further insights into the environmental variables controlling sediment accumulation in lowland gravel bed rivers. We sampled 21 sites, during spring and autumn, selected to cover a gradient of excess fine sediment. Fine sediment was sampled using a range of methods including visual assessments, the disturbance method, and suspended sediment concentrations. A range of abiotic predictors were measured during sampling, and hydrological and antecedent flow indices were derived from local flow gauging station data. The results show reach scale visual estimates of fine sediment to be significantly and highly correlated with fully quantitative estimates of total surface sediment. Multivariate regression analysis showed that flow variables (regime, antecedent, and local flow characteristics) were strong predictors of deposited sediment metrics but poor predictors of suspended sediment. Organic content was shown to be relatively independent of total sediment quantity and is likely driven by other factors which influence the supply and breakdown of organic matter.

Most lake whitefish populations within Lake Michigan are experiencing widespread population declines due to low levels of recruitment. However, the stock within Green Bay is flourishing, and various assessment tools suggest consistent recruitment to the juvenile stage each year. The distribution of offshore and drifting lake whitefish larvae were last described in the 1970s, prior to the resurgence of the southern Green Bay stock and prior to increasing knowledge of adult spawning behavior. We conducted a Green Bay wide survey of lake whitefish larvae over three years to provide an update of larval abundance and distribution and to discern influential biotic and abiotic factors that correlate to larval densities. In contrast with historical studies, our sampling illustrated high densities of larvae in both offshore and nearshore environments. Offshore expansion may be a factor in the population increase, but long term survival effects are still unknown. This study also provides the first documentation of larvae within the southern end of the bay below Chambers Island, WI and near re-colonized rivers. Average overall densities were relatively consistent each year, ranging between 29.5 and 49.6 per 1000 m3. Lake whitefish larvae were patchy in distribution and were associated with warmer and more productive waters at small spatial scales. Larval lake whitefish appear to be distributed widely throughout the entirety of Green Bay during the drift life stage, and we discuss our results in light of re-established river spawning and the overall increase in abundance.

Eugenol is an important phenylpropanoid in strawberry and the accumulation is affected by various abiotic stresses. In this study, the expression patterns of two transcription factors (TFs) (FaMYB10 and FaEOBII) and two synthetic genes (FaEGS1 and FaEGS2) involved in eugenol synthesis were characterized in Fragaria × ananassa cv. ‘Xiaobai’. Sequence analysis showed the four genes contained several cis-acting elements that were related to phytohormones and environmental stress signal responsiveness. FaEGS1 and FaEGS2 were clustered in the same group clade. The four genes were expressed in all analysed tissues and, in particular, expressed to higher relative expression levels in leaves. The expression of FaEGS1, FaEGS2, and FaEOBII was the highest in large green fruits, and FaMYB10 had the highest expression in red-ripening fruits. The amount of eugenol showed a stage-specific profile. The expression of these four genes was up-regulated by ethephon (ETH), dark, drought, heat, and salt treatments accompanied by the increase of eugenol production. Concentration and timing of cadmium treatment affected gene expression. Cadmium inhibited the expression of FaEGS1 and FaEOBII, but significantly promoted the expression of FaEGS2 and FaMYB10 and eugenol content. The results provide a basis for elucidating the role of these genes in response to abiotic stresses, and regulating the accumulation of eugenol, an important constituent of volatile compounds in many economically important and aromatic plants.

Plant root exudates serve pivotal roles in supporting plant development and interactions with the physicochemical and biological factors in the rhizosphere. Under stress conditions, root exudation is involved in enhancing plant resource-use efficiency and facilitating the crosstalk between plant and soil microbes to ameliorate stress. Although there are a large number of root exudates that remain to be characterized, recent technological advancements have allowed for the function of many exudate compounds to be elucidated. In this review, we discuss current knowledge about the key root exudates that modulate plant resource-use efficiency under various abiotic stresses including drought, aluminum toxicity, phosphorus, nitrogen, and iron deficiency. The role that key root exudates play in shaping microbial communities in the rhizosphere under stress conditions is also an important consideration addressed in this review.

Plant food production is affected by multiple abiotic and biotic stresses. To overcome these limiting factors, synthetic agrochemicals are widely used. However, more stringent worldwide regulatory policies and the public demand to reduce their application have led to the search for new ecofriendly alternatives such as biostimulants. Their commercial use is still limited, mostly due to the lack of knowledge of the molecular mechanisms responsible for their effects on plant metabolism. The horseradish Moringa oleifera has been described as a source of metabolites with biostimulant potential in agriculture. In particular, its leaf extracts (MLE) have been used to improve food production by enhancing plant growth and abiotic and biotic stress tolerance. Nevertheless, the molecular basis of changes induced by the application of MLE, in particular to the plant transcriptome, are poorly understood. In this work, using Arabidopsis thaliana as model, we determined that MLEA induced tolerance to salinity and protection against the phytopathogen Botrytis cinerea. Additionally, we characterized the transcriptional changes of phytohormone-induced genes that were caused by MLE. Our work provides novel and valuable information that can help researchers to characterize the biostimulant effects induced by the miracle plant Moringa oleifera.

The enzymatic pool of the soil is formed for a long time under the influence of many natural factors. Therefore, information on the lability of soil enzymes under the influence of the main abiotic factors is necessary for the diagnosis of the anthropogenic influence on ecosystems. The aim of the study was to determine the variability of the activity of catalase, invertase, and urease in sod-podzolic and grey forest soils in response to the main abiotic factors and model pollution. The studied areas belonged to the subzones of middle and southern taiga and mixed forests, the average annual temperature ranged from 2.9 to 6.6 ℃, and the рНHCl level of extracts from soils was in the range of 4.2-5.6. It is shown that the activity of exozymes in the soil of southern taiga and mixed forests depends most of all on the average annual temperature and pH level. No relationship between the enzyme activity and soil organic carbon was found. Artificial soil salinity led to an increase in the activity of invertase and urease. Soil contamination with zinc (25.5 and 255.0 mg / kg of dry soil) suppressed only the invertase activity. Thus, the influence of natural abiotic factors on the activity of soil enzymes was more often than the chemical load.

Graphical abstract, Environmental structure describes physical structure that can determine heterogenous spatial distribution of biotic and abiotic (nutrients, stressors etc.) components of a microorganism’s microenvironment. This study investigated the impact of micrometre-scale structure on microbial stress sensing, using yeast cells exposed to copper in microfluidic devices comprising either complex soil-like architectures or simplified environmental structures. In the soil micromodels, the responses of individual cells to inflowing medium supplemented with high copper (using cells expressing a copper-responsive pCUP1-reporter fusion) could be described neither by spatial metrics developed to quantify proximity to environmental structures and surrounding space, nor by computational modelling of fluid flow in the systems. In contrast, the proximities of cells to structures did correlate with their responses to elevated copper in microfluidic chambers that contained simplified environmental structure. Here, cells within more open spaces showed the stronger responses to the copper-supplemented inflow. These insights highlight not only the importance of structure for microbial responses to their chemical environment, but also how predictive modelling of these interactions can depend on complexity of the system, even when deploying controlled laboratory conditions and microfluidics.

Life emerged in a geochemical context, possibly in the midst of mineral substrates. However, it is not known to what extent minerals and dissolved inorganic ions could have facilitated the evolutio...

The biotic and abiotic factors responsible for determining ranges of most species are poorly understood. The Canada Jay (Perisoreus canadensis (Linnaeus, 1766)) relies on perishable cached food for over-winter survival and late-winter breeding and the persistence of cached food could be a driver of range limits. We confirmed that the Canada Jay’s lower elevational limit on Vancouver Island, British Columbia, Canada, matches that of the subalpine zone (900 m) and then conducted simulated caching experiments to examine the influence of antimicrobial properties of subalpine tree species (biotic) and of temperature (abiotic) on the preservation of cached food. We found that two high-elevation species, yellow cedar (Callitropsis nootkatensis (D. Don) D.P. Little) and Amabilis fir (Abies amabilis Douglas ex J. Forbes), preserved cached blueberries and chicken flesh better than other trees, but they also occurred well below the lower limit of Canada Jays. The effect of temperature was similarly unclear; while food cached at 1150 m retained 17% more mass than food cached at 550 m, there was no difference in percent mass remaining of food placed 70 m above versus 120 m below the Canada Jay’s lower elevational limit. Thus, we were unable to provide definitive evidence that either of the proposed abiotic or biotic factors was responsible for setting thelower elevational limit of resident Canada Jays.

Abiotic environmental factors have a major impact on the distribution and performance of plant species. For this purpose, regarding the importance of Vicia variabilis in forage production and the possibility of using it in the improvement and reclamation of oak forest understory, this study aimed to investigate the effect of soil variables and topography on the response of this species using generalized additive models in the west of Iran. The results showed that the response pattern of V. variabilis along the gradient of clay, silt, and soil saturation moisture followed the monotonic increase model. Conversely, the response of this species along the gradient of sand percentage, bare soil percentage, and content of sulfate salts in the soil followed the monotonic decrease model. The species response pattern along the gradients of electrical conductivity, lime percentage, pH of soil, soil sodium ion, phosphorus, altitude, slope, stone and gravel percentage, and canopy cover percentage of the forest overstorey followed a unimodal model, and its optimal growth limit for these factors was 0.85 dsm–1, 5.10%, 7.26, 0.38 meql–1, 35 ppm, 1 650 m, 31%, 7%, and 25%, respectively. The results of phenological studies on V. variabilis during 2018 to 2020 showed that late June/early July was the most suitable time for livestock use of this species, and the best time to collect the seeds was mid-July to the early August. Regarding the response of this plant to the gradient of studied environmental factors, it is recommended to pay attention to its habitat characteristics and ecological requirements in improvement programs on oak forests understory vegetation.

Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative’s wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds. Resumo A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.

In this chapter, we consider impacts of the landscape on resistance management through its effects on abiotic and biotic conditions, behavior of pests, and selection for resistance. For efficient development of IRM, the environment needs to be characterized with respect to the spatial and temporal distribution of the pest, the crop or toxin, refuge habitats, and variation within these elements in space and time. Without an understanding of temporal and spatial variability in natural and human-designed landscapes, resistance management plans will be difficult to implement successfully. First, we highlight how heterogeneity over space influences resistance management; then we emphasize how variability over time affects IRM.

Abiotic stresses negatively impact ecosystems and the yield of crops, and climate change will increase their frequency and intensity. Despite progress in understanding how plants respond to individual stresses, our knowledge of plant acclimatization to combined stresses typically occurring in nature is still lacking. Here, we used a plant with minimal regulatory network redundancy, Marchantia polymorpha, to study how seven abiotic stresses, alone and in 19 pairwise combinations, affect the phenotype, gene expression, and activity of cellular pathways. While the transcriptomic responses show a conserved differential gene expression between Arabidopsis and Marchantia, we also observe a strong functional and transcriptional divergence between the two species. The reconstructed high-confidence gene regulatory network demonstrates that the response to specific stresses dominates those of others by relying on a large ensemble of transcription factors. We also show that a regression model could accurately predict the gene expression under combined stresses, indicating that Marchantia performs arithmetic multiplication to respond to multiple stresses. Lastly, two online resources (https://conekt.plant.tools and http://bar.utoronto.ca/efp_marchantia/cgi-bin/efpWeb.cgi) are provided to facilitate the study of gene expression in Marchantia exposed to abiotic stresses.

Soil respiration (Rs) plays a crucial role in the terrestrial carbon cycle. We attempted to investigate how changes in water and nitrogen affect the Rs of grassland ecosystems through biotic and abiotic factors under the context of global change. We conducted a 4-year manipulative field experiment with a randomized complete block design in a 2 × 4 factorial consisting of two water addition levels and three nitrogen addition levels in a typical temperate grassland in China to explore the response of Rs to different water and nitrogen addition treatments in the growing season, and the potential factors controlling Rs were analyzed using structural equation modeling (SEM). Water addition significantly enhanced the cumulative Rs in all years. The precipitation during the months of vigorous plant growth (May to July) was an important factor in determining the average Rs during the growing season. Nitrogen addition alone had no significant impacts on Rs except for short-term positive effects caused by low nitrogen addition (25 kg N ha−1 yr−1) during the period after nitrogen application in the first year. Although soil microbes and plant roots contributed to Rs, the main factors controlling Rs were still temperature and soil moisture. These findings indicate that water addition could promote Rs in semiarid grassland ecosystems. Changes in environmental factors could control Rs by affecting soil microorganisms and plant roots activity.

Key Message Endophytes are crucial for the promotion of rice growth and stress tolerance and can be used to increase rice crop yield. Endophytes can thus be exploited in biotechnology and genetic engineering as eco-friendly and cost-effective means for the development of high-yielding and stress-tolerant rice plants. Abstract Rice (Oryza sativa) crop is continuously subjected to biotic and abiotic stresses, compromising growth and consequently yield. The situation is exacerbated by climate change impacting on ecosystems and biodiversity. Genetic engineering has been used to develop stress-tolerant rice, alongside physical and chemical methods to mitigate the effect of these stresses. However, the success of these strategies has been hindered by short-lived field success and public concern on adverse effects associated. The limited success in the field of stress-tolerant cultivars developed through breeding or transgenic approaches is due to the complex nature of stress tolerance as well as to the resistance breakdown caused by accelerated evolution of pathogens. It is therefore necessary to develop novel and acceptable strategies to enhance rice stress tolerance and durable resistance and consequently improve yield. In the last decade, plant growth promoting (PGP) microbes, especially endophytes, have drawn the attention of agricultural scientists worldwide, due to their ability to mitigate environmental stresses in crops, without causing adverse effects. Increasing evidence indicates that endophytes effectively confer fitness benefits also to rice under biotic and abiotic stress conditions. Endophyte-produced metabolites can control the expression of stress-responsive genes and improve the physiological performance and growth of rice plants. This review highlights the current evidence available for PGP microbe-promoted tolerance of rice to abiotic stresses such as salinity and drought and to biotic ones, with special emphasis on endophytes. Associated molecular mechanisms are illustrated, and prospects for sustainable rice production also in the light of the impending climate change, discussed.

In semi-arid Mediterranean ecosystems, biotic and abiotic constraints have led to intense forest destruction and ecosystem deterioration and particularly to limitation in the production of Argan tree. Reforestation is thus more than ever a major challenge and an absolute necessity. The use of arbuscular mycorrhizal fungi (AMF) is of great importance in the processes of sustainable regeneration of the vegetation cover, given their roles in the improvement of plant growth and in the protection of soils. In the current study, Argan seedlings were inoculated with five arbuscular mycorrhizal fungi complexes and six arbuscular mycorrhizal fungi monospecific isolates. Growth, nutrition, photosynthetic pigments, and mycorrhizal colonization were under study. The soil samples were obtained from different ecosystems. Trap culture with Maize (Zea mays L.) was used for the production of mycorrhizal inoculum directly for complexes. Monospecific isolates were then produced from spore suspension using the technique of micropipette tips. Germinated seeds of Argan tree were inoculated separately with eleven fungal inoculants, under nursery conditions. Eight-month aged seedlings were compared for their growth and nutritional status. All the considered AMF inoculants stimulated significantly the growth of Argan seedlings; an increase in plant height between 33 and 70% was recorded. The aerial dry weight showed an increase of 62 to 124%, and the root dry weight showed an increase of 24 to 86% compared to the control. Similarly, the mineral contents in inoculated seedlings were significantly increased compared to the control non-inoculated seedlings. The analysis of the chlorophyll contents in leaves showed a significant improvement in inoculated seedlings. In conclusion, this first use of arbuscular mycorrhizal fungi isolates had shown that either complexes or monospecific isolates could improve significantly growth, mineral nutrition, and photosynthesis of Argan seedlings under nursery conditions. Hence, the use of inoculation with suitable consortium from these isolates is a recommended eco-friendly strategy for the restoration of degraded Argan ecosystems.

Carbon monoxide (CO), nitric oxide (NO) and hydrogen sulfide (H2S) are gasotransmitters known for their roles in plant response to (a)biotic stresses. The crosstalk between these gasotransmitters and potassium ions (K+) has received considerable attention in recent years, particularly due to the dual role of K+ as an essential mineral nutrient and a promoter of plant tolerance to abiotic stress. This review brings together what it is known about the interplay among NO, CO, H2S and K+ in plants with focus on the response to high salinity. Some findings obtained for plants under water deficit and metal stress are also presented and discussed since both abiotic stresses share similarities with salt stress. The molecular targets of the gasotransmitters NO, CO and H2S in root and guard cells that drive plant tolerance to salt stress are highlighted as well.

Erratic rainfall often results in intermittent drought and/or waterlogging and limits maize (Zea mays L.) productivity in many parts of the Asian tropics. Developing climate-resilient maize germplasm possessing tolerance to these key abiotic stresses without a yield penalty under optimal growing conditions is a challenge for breeders working in stress-vulnerable agro-ecologies in the region. Breeding stress-resilient maize for rainfed stress-prone ecologies is identified as one of the priority areas for CIMMYT-Asia maize program. We applied rapid cycle genomic selection (RCGS) on two multiparent yellow synthetic populations (MYS-1 and MYS-2) to improve grain yield simultaneously under drought and waterlogging conditions using genomic-estimated breeding values (GEBVs). Also, the populations were simultaneously advanced using recurrent phenotypic selection (PS) by exposing them to managed drought and waterlogging and intermating tolerant plants from the two selection environments. Selection cycles per se (C1, C2, and C3) of the two populations developed using RCGS and PS approach and their test-cross progenies were evaluated separately in multilocation trials under managed drought, waterlogging, and optimal moisture conditions. Significant genetic gains were observed with both GS and PS, except with PS in MYS-2 under drought and with GS in MYS-1 under waterlogging. Realized genetic gains from GS were relatively higher under drought conditions (110 and 135 kg ha−1 year−1) compared to waterlogging (38 and 113 kg ha−1 year−1) in both MYS-1 and MYS-2, respectively. However, under waterlogging stress PS showed at par or better than GS as gain per year with PS was 80 and 90 kg ha−1, whereas with GS it was 90 and 43 kg ha−1 for MYS-1 and MYS-2, respectively. Our findings suggested that careful constitution of a multiparent population by involving trait donors for targeted stresses, along with elite high-yielding parents from diverse genetic background, and its improvement using RCGS is an effective breeding approach to build multiple stress tolerance without compromising yield when tested under optimal conditions.

Biochar application can influence soil nitrogen (N) cycle through biological and abiotic processes. However, studies on comprehensive examination of the effects of biochar application on microbially mediated N‐cycling processes (N mineralization, nitrification, denitrification, and fixation) and soil N fate (i.e., plant N uptake, soil N2O emission, and N leaching) are warranted. Therefore, the aim of this study was to examine the effects of biochar application on soil N transformation, microbial functional gene abundance, enzyme activity, and plant N uptake. To achieve the objective of this study, a meta‐analysis involving 131 peer‐reviewed field experiments was conducted. Results showed that field application of biochar significantly enhanced soil NH4+ and NO3‐ content, N mineralization, nitrification, N2 fixation, and plant N uptake by 5.3%, 3.7%, 15.3%, 48.5%, 14.7%, and 18.3%, respectively, but reduced N2O emissions and N leaching by 14.9% and 10.9%, respectively. Biochar application also increased the abundance of soil denitrifying/nitrifying genes (amoA, narG, nirS/nirK+S, and nosZ), proportion of N2 fixation bacteria, and N‐acetyl‐glucosaminidase activity by 18.6%–87.6%. Soil NO3‐ content was positively correlated with AOA‐amoA abundance, and soil N2O emission was positively correlated with the relative abundance of genes (e.g., amoA, narG, and nirS/nirK) involved in N2O production. Furthermore, long‐term biochar application tended to increase AOB‐amoA and nirK+S abundance, especially soil N2O emission and N leaching. Overall, the findings of this study indicated that biochar application accelerated microbially mediated N‐cycling processes under field conditions, thereby enhancing soil N availability and plant productivity. However, long‐term biochar application may increase N losses. Therefore, future studies should be conducted to examine the effect of long‐term biochar application on the soil N cycle and the underlying microbial mechanisms.

While many cities have embraced urban agriculture, research examining crop productivity in urban environments is limited. Little is known about how abiotic and biotic factors affecting productivity on urban farms compare with those in rural environments. In this study, we investigated environmental factors influencing strawberry (Fragaria x ananassa) productivity for two cultivars at ten farms across a rural-urban gradient in Michigan, USA over a three-year period. We evaluated key drivers of production, namely temperature, pathogens, pests, and pollinators, which we hypothesized would be altered by urbanization. We found no direct effect of urbanization on strawberry production or fruit pathogen and pest damage. However, temperature, an environmental correlate of urbanization, significantly influenced crop productivity. In particular, cooler temperatures at rural farms and warmer temperatures at urban farms limited fruit number in the peak production year. We found no relationship between urbanization and overall abundances of arthropod pests, their predators, or pollinators. However, we found opposite effects of urbanization for two arthropod groups – Vespidae (paper wasps) and Araneae (spiders). Vespidae abundance was positively associated with increased urbanization. These omnivorous wasps are both predators of strawberry pests and pests of fruits themselves. Conversely, spiders, which are predators of strawberry pests, were negatively associated with urbanization. Greater pollinator visitation incrementally improved fruit weight, but only at low to moderate levels of pathogen and pest damage. At high levels of damage, the benefits of pollination were not apparent. Our study reveals that environmental drivers of variation in crop yield, such as pathogen and herbivore damage and pollinator visitation, can be comparable across rural-urban gradients. Some factors, however, such as temperature stress and the abundances of certain pest and beneficial organisms may be affected by urbanization.

Glycogen synthase kinase 3 (GSK3) family members are highly conserved serine/threonine protein kinases in eukaryotes. Unlike animals, plants have evolved with multiple homologs of GSK3s involved in a diverse array of biological processes. Emerging evidence suggests that GSK3s act as signaling hubs for integrating perception and transduction of diverse signals required for plant development and responses to abiotic and biotic cues. Here we review recent advances in understanding the molecular interactions between GSK3s and an expanding spectrum of their upstream regulators and downstream substrates in plants. We further discuss how GSK3s act as key signaling nodes of multilayer regulation of plant development and stress response through either being regulated at the post-translational level or regulating their substrates via phosphorylation.

In recent years, modern agroclimatic environmental conditions in the European North of the Russian Federation are determined by constant fluctuations of biotic and abiotic factors, which require a high level of plasticity and stability of crop yield and quantitative characteristics from cultivars used in agricultural production. Therefore, determining the plant response to changing environmental factors in order to select the most promising breeding seeds, is an important task for breeders. The research was conducted on experimental field of N. Laverov Federal Center for Integrated Arctic Research of the Ural Branch of the Russian Academy of Sciences, in the nursery of competitive variety testing in 2017—2019. Cultivars of spring barley of local selection were studied. Indicators of cultivar plasticity and stability were calculated by the method of S.A. Eberhart, W.A. Rassell (1966), the indicator of genetic flexibility — by the method of R.A. Udachin (1990). Various weather conditions during the research period enabled to evaluate the breeding material comprehensively. The hydrothermal coefficient (according to G.T. Selyaninov) varied from 1.85 to 3.06 during the research years. Ten cultivar samples of spring barley were analyzed to identify a plastic stable genotype. As a result, a high level of stability was shown by samples k-037712 (Ϭ 2 = 0.01), k-038404 (Ϭ 2 = 0.02). Samples with a neutral genotype were identified: k-039257, k-036982 ( b i < 1) and a sample weakly responding to environmental changes — k-038806 ( b i = 0.23). The b i value is very close to 1 in Kotlassky cultivar, which shows a high ecological plasticity. Sample k-038806 has the lowest coefficient of linear regression (0.23), therefore, it is suitable for cultivation on unfertilized soils. The selected genetic sources will be used in breeding to develop highly productive cultivars of spring barley for the conditions of the European North of the Russian Federation.

GATA transcription factors have been reported to function in plant growth and development and during various biotic/abiotic stresses in Arabidopsis and rice. However, the functions of wheat GATAs, particularly in the regulation of seed dormancy and germination, remain unclear. Here, we identified 78 TaGATAs in wheat and divided them into five subfamilies. Sixty-four paralogous pairs and 52 orthologous pairs were obtained, and Ka/Ks ratios showed that the TaGATAs had undergone strong purifying election during the evolutionary process. Triplet analysis indicated that a high homologue retention rate could explain the large number of TaGATAs in wheat. Gene structure analysis revealed that most members of the same subfamily had similar structures, and subcellular localization prediction indicated that most TaGATAs were located in the nucleus. Gene ontology annotation results showed that most TaGATAs had molecular functions in DNA and zinc binding, and promoter analysis suggested that they may play important roles in growth, development, and biotic/abiotic stress response. We combined three microarray datasets with qRT-PCR expression data from wheat varieties of contrasting dormancy and pre-harvest sprouting resistance levels during imbibition in order to identify ten candidate genes (TaGATA17/-25/-34/-37/-40/-46/-48/-51/-72/-73) that may be involved in the regulation of seed dormancy and germination in wheat. These findings provide valuable information for further dissection of TaGATA functions in the regulation of seed dormancy and germination, thereby enabling the improvement of wheat pre-harvest sprouting resistance by gene pyramiding.

The lampricides TFM and niclosamide are added to streams to control invasive larval sea lamprey (Petromyzon marinus) populations in the Laurentian Great Lakes. Lampricide effectiveness depends upon TFM and niclosamide bioavailability which is influenced by both abiotic and biotic factors. For example, at lower pH, TFM bioavailability is higher because a greater proportion exists as un-ionized TFM (TFM-OH), which easily crosses the gills. At higher pH, however, the negatively charged ionized species of TFM (TFM-O−) predominates, which is less easily taken-up, meaning more TFM must be applied. Although water alkalinity does not directly affect TFM speciation, as a buffer it influences how much expired water crossing the gills is acidified by CO2 and metabolic acid excretion. In poorly buffered waters, greater acidification of the expired water increases TFM bioavailability in the gill microenvironment than in better buffered, higher alkalinity waters where more TFM must be applied. Hence, sea lamprey and non-target fishes such as lake sturgeon (Acipenser fulvescens) are more sensitive to lampricides in low pH, low alkalinity waters. Differences in gill structure and microenvironment acidification might also explain why TFM sensitivity of young-of-the-year lake sturgeon approaches or exceeds that of sea lamprey in higher alkalinity waters. Other biotic factors such as body size and metabolic rate also contribute to differences in lampricide sensitivity. We conclude that better understanding of the abiotic and biotic factors influencing lampricide bioavailability can be used to refine treatment protocols to improve lampricide effectiveness and to better protect non-target fishes from lampricide toxicity.

Brassinosteroids (BRs) are the sixth important plant hormones that induce their effect at micro-level concentration. The importance of its analogous under in vitro condition for many studies includes the study of response in plants aimed at improving various developmental, physiological, morphological, biochemical processes without the involvement of climatic factors, nutrients and diseases. BR improves and increases regeneration and multiplication rate by induction of callus growth, somatic embryos, tracheary elements, shoot elongation, formation of 2embryogenic tissue, stimulation of branch elongation, etc. These provide rapid disease-free clonal propagation of improved varieties within less time and space. BRs improve photosynthetic processes, antioxidant enzymes activities, synthetic seed production and elicitation of secondary metabolites production. Most importantly, it provides resistance from abiotic stresses, for example, oxidative and salinity stress. This review summarizes role of brassinosteroid and its various analogs in improving different morphological, physiological and biochemical attributes in various crop plants grown in vitro, both under normal as well as abiotic stress conditions.

Animal populations are assessed to estimate rates of artificial and natural mortality at ecologically relevant spatial and temporal scales to develop exploitation quotas. But how the population’s natural mortality rate and how the ability to observe the population changes through time are poorly understood in most invasive fishes, despite efforts to control their populations. By investigating a 30-year abundance index of invasive sea lamprey (Petromyzon marinus) in Lake Superior, we found that the index was highly correlated (R2 = 0.75) with biotic and abiotic factors hypothesized to influence sea lamprey natural mortality and their availability to index traps. The index was lowest in years (1) following winters with below average ice cover on Lake Superior, (2) when stream discharge during sea lamprey migration was below average, (3) when adult sea lamprey were smaller than average, and (4) when adult sea lamprey were more likely to be distributed in tributaries on the east side of Lake Superior. These results highlight the need for policy makers to consider invasive species abundance indexes not just in the context of control effort, but also in the context of biotic and abiotic conditions because they could markedly influence natural mortality or the ability to observe highly suppressed populations.

Silicon (Si) is known to alleviate the adverse impact of different abiotic and biotic stresses by different mechanisms including morphological, physiological, and genetic changes. Photosynthesis, one of the most important physiological processes in the plant is sensitive to different stress factors. Several studies have shown that Si ameliorates the stress effects on photosynthesis by protecting photosynthetic machinery and its function. In stressed plants, several photosynthesis-related processes including PSII maximum photochemical quantum yield (Fv/Fm), the yield of photosystem II (φPSII), electron transport rates (ETR), and photochemical quenching (qP) were observed to be regulated when supplemented with Si, which indicates that Si effectively protects the photosynthetic machinery. In addition, studies also suggested that Si is capable enough to maintain the uneven swelling, disintegrated, and missing thylakoid membranes caused during stress. Furthermore, several photosynthesis-related genes were also regulated by Si supplementation. Taking into account the key impact of Si on the evolutionarily conserved process of photosynthesis in plants, this review article is focused on the aspects of silicon and photosynthesis interrelationships during stress and signaling pathways. The assemblages of this discussion shall fulfill the lack of constructive literature related to the influence of Si on one of the most dynamic and important processes of plant life i.e. photosynthesis. Previous article in issue

Hyptis suaveolens is an exotic plant that has become established in Nigeria because it is grows vigorously and produces allelochemicals that adversely affect the growth of adjacent plants. In this study, we predict the distribution of Hyptis suaveolens in Nigeria using a Maximum Entropy modelling approach. Pearson correlations were used to select five bioclimatic variables to which type of soil and altitude were added to give a total of seven environmental variables that were then included in the MaxEnt model. This model predicts that Hyptis suaveolens can colonize 25%, 45% and 25% of the total land area in FCT, Nasarawa and the River States in Nigeria. In addition, Hyptis suaveolens in Nigeria grows mainly in sandy clay and sandy loam soils. Bioclimatic conditions most suitable for this species include temperatures between 26– 30 °C, 9–10 hour photoperiod, low altitudes of around 200–800 m and rainfall within the range of 200–800mm. The MaxEnt model indicates that Hyptis suaveolens is currently a threat to the survival of native species of plants in the North Central part of Nigeria. The MaxEnt model further reveals that because of its high adaptability and tolerance of changes in abiotic factors, Hyptis suaveolens is likely to invade a new environment, the humid forest zone in Nigeria. As this species can become very abundant, we recommend that its spread is monitored and controlled, particularly in areas of high suitability.

Both abiotic environmental conditions and variation in social environment are known to impact the acquisition of sexual signals. However, the influences of abiotic environmental and social factors are rarely compared to each other. Here we test the relative importance of these factors in determining whether and when male red-backed fairy-wrens, Malurus melanocephalus, moult into ornamented breeding plumage, a known sexual signal. One-year-old male red-backed fairy-wrens vary in whether or not they acquire ornamentation, whereas males age 2 years and older vary in their timing of ornament acquisition. It is unclear whether these processes are determined by the same or different factors, and we examined both events using a combination of long-term breeding records and nonbreeding social networks. We found that 1-year-old males that paired prior to the start of the breeding season were more likely to acquire ornamented plumage, but rainfall did not influence whether 1-year-old males acquired ornamented plumage. Thus, for young individuals, social cues appear to play a larger role than abiotic environmental factors in determining ornament acquisition. For older males, timing of ornamented plumage acquisition was constrained by rainfall, with drier nonbreeding seasons leading to poorer physiological condition and later moult dates. Thus, sexual signal variation in older males appears to be a condition-dependent trait, driven by abiotic environmental and physiological factors rather than social cues. These findings reveal that factors influencing sexual signal expression can vary with age when age classes exhibit different forms of signal variation. Our results suggest that social environment may drive sexual signal variation in young individuals, whereas abiotic environmental variation may drive sexual signal variation in older individuals.

Wildflower plantings are an important mitigation tool within agri-environmental schemes to counter insect decline in resource-scarce agricultural landscapes. Effectiveness of wildflower plantings for insect conservation is typically studied at the community or species level. It is the individual, however, that is subject to changing abiotic and biotic conditions, not the species per se. Accordingly, functional traits of individuals, i.e., the intraspecific functional diversity within species, likely mediate responses to wildflower resources and landscape context. Here we focused on the ecologically and economically important wild insect pollinator Bombus terrestris to study its intraspecific functional diversity and plant-pollinator individual interactions in wildflower plantings. We found considerable trait variation among flower-visiting B. terrestris workers. Locally, this variation could be attributed to flowering plant traits, with larger workers visiting larger inflorescences and individuals with longer tongues preferentially feeding on zygomorphic but not radial symmetric flowers. In addition, wildflower plantings with high floral abundance attracted individuals with larger pollen baskets. At the landscape scale, increasing proportion of arable land resulted in smaller B. terrestris individuals in wildflower plantings, and a decrease in the overall size diversity of workers. These findings highlight the so far little considered role of intraspecific variation in functional traits of wild pollinators, which can mediate the trait-matching between plants and pollinator individuals. Landscape simplification from agriculture threatens intraspecific pollinator diversity, with potential harmful effects for pollinator fitness and plant reproduction. Tailored wildflower plantings can thus serve as an important tool to increase intraspecific variation in simplified landscapes. When designing seed mixtures for these plantings, high complementarity in plant traits is key for promoting high intraspecific trait diversity of bumblebees and potentially of other associated insect species.

Species interactions are important for determining the biological organization of natural communities. Presumably, as interacting organisms become more similar in resource niches, the magni...

Understanding the temporal variation in abundance patterns of vector or potential vector species, as well as the abiotic factors associated with these patterns, enables the creation of strategic measures aimed at preventing diseases spread by these organisms. Here, we evaluate through circular and linear analyses the temporal variation in abundance patterns of native mosquito species and verify how abiotic factors (temperature and rainfall) have influenced these patterns. For this purpose, fortnightly collections were carried out during one year in a remnant of the Atlantic Forest in Southern Brazil. We collected 1891 specimens belonging to 24 species. From those, 10 species were abundant enough to evaluate temporal variation in abundance patterns. We found different periods of occurrence for different species of mosquitoes and the distribution of abundances also differed throughout the year. Temperature was the main abiotic factor associated with temporal variation in abundance patterns presented by mosquito species. In this way, the application of these analyses is particularly interesting for the understanding of temporal variation in abundance patterns and subsequent adoption of preventive strategies for organisms of medical importance such as mosquitoes.

The endophytic microbiome may influence the ecological performance of plants, including forest trees. Various abiotic and biotic factors may shape the endophyte communities directly but also indirectly, by modifying the quality of host plants as a substrate. We hypothesized that potentially antifungal or fungistatic condensed tannins (CTs) would determine the quality of aspen (Populus tremula) leaves as a substrate for endophytic fungi. By subjecting the plants to nitrogen fertilization (N) or herbivory (H; leaf beetles) we aimed to change the internal “chemical landscape”, especially the CT levels, in aspen leaves. We expected that this would lead to changes in the fungal community composition, in line with the predictions of heterogeneity-diversity relationship hypothesis. To test this we conducted a greenhouse study where aspen plants were subjected to N and H treatments, individually or in combination. The chemical status of the leaves was analysed using GC/MS (114 metabolites), LC/MS (11 phenolics) and UV-spectrometry (CTs) and the endophytic communities were characterized using culture-dependent sequencing. Nitrogen treatment, alone or in combination with herbivory had a suppressing effect on the concentration and within-treatment variation in the CT precursors, catechins, and resulted in similar trend also in CTs. Nitrogen increased the concentration of certain amino acids, and it also tended to increase most of the analysed sugars sugars. Herbivory had a negligible effect on chemical traits. In N-treated plants, the endophyte richness and abundance were higher than in plants exposed to H, but in general, the diversity of the culturable endophytes remaind stable despite the subtle changes in leaf chemistry.

KEY MESSAGE We propose that anion channels are essential players for green plants to respond and adapt to the abiotic stresses associated changing climate via reviewing the literature and analyzing the molecular evolution, comparative genetic analysis, and bioinformatics analysis of the key anion channel gene families. Climate change-induced abiotic stresses including heatwave, elevated CO2, drought, and flooding, had a major impact on plant growth in the last few decades. This scenario could lead to the exposure of plants to various stresses. Anion channels are confirmed as the key factors in plant stress responses, which exist in the green lineage plants. Numerous studies on anion channels have shed light on their protein structure, ion selectivity and permeability, gating characteristics, and regulatory mechanisms, but a great quantity of questions remain poorly understand. Here, we review function of plant anion channels in cell signaling to improve plant response to environmental stresses, focusing on climate change related abiotic stresses. We investigate the molecular response and evolution of plant slow anion channel, aluminum-activated malate transporter, chloride channel, voltage-dependent anion channel, and mechanosensitive-like anion channel in green plant. Furthermore, comparative genetic and bioinformatic analysis reveal the conservation of these anion channel gene families. We also discuss the tissue and stress specific expression, molecular regulation, and signaling transduction of those anion channels. We propose that anion channels are essential players for green plants to adapt in a diverse environment, calling for more fundamental and practical studies on those anion channels towards sustainable food production and ecosystem health in the future.

The conservation of protected areas is nowadays one of the concerns of international and national institutions. This study aims to contribute to better conservation of the ichthyological fauna of the lagoon area of the Azagny National Park (PNA). This national park has been dealing with the harmful effects of human activities for years. Thus, from March 2019 to February 2020, sampling campaigns were carried out to characterize this space, for better conservation. The results obtained are based on the analysis of abiotic and biotic (fish) data collected at 6 stations. The physicochemical parameters were measured using a multiparameter and the fish population collected using 10 gillnet batteries of 10, 25, 30, 35, 40 and 50 mm mesh void. The analysis of the ichthyological population of the lagoon area reveals a diversity of 53 species belonging to 30 families and 12 orders. 11 species were newly collected while 31 species previously recorded in these hydrosystems were not captured in the present study. The Shannon (H’> 2) and Equitability (E> 0.5) indices calculated reflect a good organization and stability of the ichthyological population of the hydrosystems of the PNA lagoon zone. The Monte-Carlo test indicates that the variables rate of nitrate, width, rate of dissolved oxygen, water temperature, alkalinity, salinity, rate of dissolved solid and phosphorus are those which discriminate specific richness, abundance and the distribution of the stand.

Bread wheat (Triticum aestivum L.) plays a major role among the few crop species being extensively grown as staple food sources. As the human population grows, new methods and approaches must be found to attain wheat cultivars with improved characteristics. The challenge now is to produce higher-yielding varieties with good technological quality that are resistant or tolerant to a wide range of biotic and abiotic stresses. However, because of the critical nutritional status of human population, there is an urgent need for development of such wheat varieties that would be more nutritious (with improved protein, zinc, iron, etc. value), meeting our health demands. This article summarises present status in this field.