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1.
Oecologia ; 192(4): 1013-1022, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32277360

RESUMO

Across latitudinal clines, the juvenile developmental rates of ectotherms often covary with the length of the growing season, due to life-history trade-offs imposed by the time-constrained environments. However, as the start of the growing season often varies substantially across years, adaptive parental effects on juvenile developmental rates may mediate the costs of a delayed season. By employing a meta-analysis, we tested whether larval developmental rates across a latitudinal cline of the common frog (Rana temporaria) are affected by fluctuating onsets of breeding, across years. We predicted that larval developmental rate will be inversely related to the onset of breeding, and that northern populations will be more prone to shorten their developmental rate in response to late breeding, as the costs of delayed metamorphosis should be highest in areas with a shorter growing season. We found that the larval period of both northern and southern populations responded to parental environmental conditions to a similar degree in absolute terms, but in different directions. In northern populations, a late season start correlated with decreased development time, suggesting that the evolution of parental effects aids population persistence in time-constrained environments. In southern populations, late season start correlated with increased development time, which could potentially be explained as a predator avoidance strategy. Our findings suggest that local ecological variables can induce adaptive parental effects, but responses are complex, and likely trade-off with other ecological factors.


Assuntos
Traços de História de Vida , Animais , Larva , Metamorfose Biológica , Rana temporaria , Estações do Ano
2.
Oecologia ; 193(1): 97-107, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32306115

RESUMO

Life history theory predicts trade-offs in allocation between survival, maintenance, growth, and reproduction, especially when resources are scarce. Individual variation in resource acquisition can affect trade-offs, but is often unaccounted for. We quantified the fitness costs of reproduction, accounting for environmental conditions, maternal characteristics and individual variation. We analyzed 10 years of data from marked kangaroos to evaluate how reproductive allocation affected annual mass change and skeletal growth, subsequent fecundity and weaning success, and survival, accounting for maternal mass or size and forage availability. Through repeated measurements of 76-91 females, we investigated how trade-offs varied within and between individuals, assessing whether individual variation could mask population-level trade-offs. In poor environments, females that weaned an offspring lost mass. Females that nursed an offspring for > 7 months had reduced skeletal growth. Females that did not gain mass over the previous 12 months rarely reproduced, especially if they had nursed an offspring for > 7 months the previous year. Reproductive allocation had no effect on weaning success, which was very low, and did not affect maternal survival, suggesting a conservative strategy. Disentangling within- and between-individual responses revealed trade-offs within individuals, but because individuals did not vary in their responses to earlier effort, these trade-offs did not drive population trends. The interacting effects of environmental conditions, maternal characteristics and individual variation on allocation trade-offs demonstrate the importance of long-term monitoring for understanding life history variations in changing environments.


Assuntos
Traços de História de Vida , Reprodução , Animais , Feminino , Fertilidade , Macropodidae
3.
Sci Total Environ ; 720: 137397, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32143035

RESUMO

In the current global change context, it is urgent to anticipate the fate of tropical forests. This means understanding tree community response to disturbance and the underlying processes. In that respect, we aim here to clarify taxonomic and functional post-disturbance trajectories, and determine the scope of the Intermediate Disturbance Hypothesis (IDH) that remains debated in tropical forests. We analyzed community trajectories following a disturbance gradient from 10 to 60% of above-ground biomass loss in a Neotropical forest over 30 years. We considered trajectories along time of community taxonomic and functional trajectories in terms of richness, evenness, composition, and redundancy. We based on the annual botanical inventories of 75 ha of a Neotropical forest and on large trait datasets comprising seven leaf, stem, and life-history traits. We identified a decoupling between taxonomic composition, differing among communities, and functional composition, similar among communities and convergent in the functional space. The taxonomic diversity followed humped-shaped trajectories along time after disturbance depending on the initial disturbance intensity, which validated the IDH (Intermediate Disturbance Hypothesis). The functional diversity trajectories, however, were homogeneous among plots and dismissed the IDH. We explained this decoupling by the variations in community functional redundancy that mitigated the functional impact of disturbance. Although consistent, the recovery of community composition, diversity, and redundancy remained divergent from the initial state after 30 years. These results acknowledged the need of decades-long cycles without disturbance to ensure community complete recovery.


Assuntos
Florestas , Traços de História de Vida , Biodiversidade , Biomassa , Árvores
4.
PLoS One ; 15(2): e0229689, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32106260

RESUMO

BACKGROUND: Conservation strategies are urgently needed for tropical turtles that are increasingly threatened by unsustainable exploitation. Studies conducted exclusively in temperate zones have revealed that typical turtle life history traits (including delayed sexual maturity and high adult survivorship) make sustainable harvest programs an unviable strategy for turtle conservation. However, most turtles are tropical in distribution and the tropics have higher, more constant and more extended ambient temperature regimes that, in general, are more favorable for population growth. METHODS: To estimate the capacity of temperate and tropical turtles to sustain harvest, we synthesized life-history traits from 165 predominantly freshwater turtle species in 12 families (Carettochelydae, Chelidae, Chelydridae, Dermatemydidae, Emydidae, Geoemydidae, Kinosternidae, Pelomedusidae, Platysternidae, Podocnemididae, Staurotypidae and Trionychidae). The influence of climate variables and latitude on turtle life-history traits (clutch size, clutch frequency, age at sexual maturity, and annual adult survival) were examined using Generalized Additive Models. The biological feasibility of sustainable harvest in temperate and tropical species was evaluated using a sensitivity analysis of population growth rates obtained from stage-structured matrix population models. RESULTS: Turtles at low latitudes (tropical zones) exhibit smaller clutch sizes, higher clutch frequency, and earlier age at sexual maturity than those at high latitudes (temperate zones). Adult survival increased weakly with latitude and declined significantly with increasing bioclimatic temperature (mean temperature of warmest quarter). A modeling synthesis of these data indicates that the interplay of life-history traits does not create higher harvest opportunity in adults of tropical species. Yet, we found potential for sustainable exploitation of eggs in tropical species. CONCLUSIONS: Sustainable harvest as a conservation strategy for tropical turtles appears to be as biologically problematic as in temperature zones and likely only possible if the focus is on limited harvest of eggs. Further studies are urgently needed to understand how the predicted population surplus in early life stages can be most effectively incorporated into conservation programs for tropical turtles.


Assuntos
Conservação dos Recursos Naturais/métodos , Tartarugas , Animais , Clima , Tamanho da Ninhada , Estudos de Viabilidade , Feminino , Água Doce , Traços de História de Vida , Masculino , Dinâmica Populacional , Temperatura , Clima Tropical , Tartarugas/crescimento & desenvolvimento , Tartarugas/fisiologia
5.
Ecol Lett ; 23(5): 811-820, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32090452

RESUMO

Fluctuating population density in stochastic environments can contribute to maintain life-history variation within populations via density-dependent selection. We used individual-based data from a population of Soay sheep to examine variation in life-history strategies at high and low population density. We incorporated life-history trade-offs among survival, reproduction and body mass growth into structured population models and found support for the prediction that different life-history strategies are optimal at low and high population densities. Shorter generation times and lower asymptotic body mass were selected for in high-density environments even though heavier individuals had higher probabilities to survive and reproduce. In contrast, greater asymptotic body mass and longer generation times were optimal at low population density. If populations fluctuate between high density when resources are scarce, and low densities when they are abundant, the variation in density will generate fluctuating selection for different life-history strategies, that could act to maintain life-history variation.


Assuntos
Evolução Biológica , Traços de História de Vida , Animais , Densidade Demográfica , Dinâmica Populacional , Reprodução , Ovinos
6.
Sci Total Environ ; 714: 136567, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31981867

RESUMO

The aim of the study was to investigate the influence of microplastics (MPs) on the ecotoxicity of common contaminants of aquatic ecosystems. As a model contaminant, the hydrophobic pesticide deltamethrin (DM) was chosen, and its effects on life history traits of Daphnia magna were studied in the presence or absence of polyethylene MPs. Commercialized DM and MPs obtained as dry powder were used in the experiment. According the manufacturer (Cospheric, Santa Barbara, CA, USA) MPs were spherical (1-4 µm in diameter), had a density of 0.96 g/cm-3 and were without any solvent. Three concentrations of polyethylene MPs were tested (0, 1, 10 mg/L) with two realistic concentrations of DM (0 and 40 ng/L) and a solvent control (acetone). During the 21 d experiment, D. magna neonates were individually exposed to the treatments, and the effects of MPs and DM alone and together were evaluated by assessing survival, number of cumulative molts, days to first brood, number of broods, number of neonates per surviving adult, and body length. Significant detrimental effects on survival were only observed for the two mixture treatments. DM alone (40 ng/L) delayed the days to first brood and reduced the number of neonates per surviving adult, whereas MPs alone (10 mg/L) induced significant reduction in the number of juveniles by surviving adults. The combined exposure to DM and MPs clearly had a synergistic effect on survival, brood number, and number of neonates per surviving female. For example, compared to exposure to 40 ng/L of DM alone, the addition of 1 mg/L of MPs resulted in a 51.1% reduction in number of neonates per surviving female and a 46% reduction in brood number. These results suggest the potential drastic effects of this kind of mixed exposure on daphnid populations, which are key components of freshwater food webs.


Assuntos
Traços de História de Vida , Animais , Daphnia , Ecossistema , Feminino , Inseticidas , Microplásticos , Nitrilos , Piretrinas , Reprodução , Poluentes Químicos da Água
7.
PLoS One ; 15(1): e0227361, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945101

RESUMO

A species presence at a particular site can change over time, resulting in temporally dynamic species pools. Ecological niche models provide estimates of species presence at different time intervals. The avifauna of La Brea includes approximately 120 species dating to approximately 15,000 years ago. Niche models predicted presence at the Last Glacial Maximum for over 90% of 89 landbird species. This confirms that niche modeling produces sensible range estimates at the Last Glacial Maximum. For 97 currently local species that are as yet undocumented at La Brea over 90% were predicted to occur; absence is due to insufficient study, lack of the ecological niche, transient occurrence or a behavioral ability to avoid entrapment. Our 366 niche models provide a prospective checklist of the landbird fauna of La Brea. The models indicate fluidity in life history strategies and a higher proportion of resident birds at the LGM (88% to 60%). We evaluated a subset of 103 species in breeding and winter periods using two climate models (MIROC-ESM, CCSM4) with a variety of differing parameters, finding differences in 5% of the niche models. Niche breadths in bark-foraging birds changed little between the present and LGM, suggesting that greater species diversity at the LGM was due to greater niche availability rather than contractions of niche breadths (i.e., niche partitioning).


Assuntos
Biodiversidade , Aves , Mudança Climática , Traços de História de Vida , Animais , Ecossistema , Extinção Biológica , Los Angeles , Modelos Biológicos , Dinâmica Populacional
8.
Sci Total Environ ; 705: 135827, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31972953

RESUMO

The gut microbiota has a crucial role in host physiology and fitness. Host-microbiota relationships can be disrupted by environmental stressors, which further affect host growth and survival. However, the link between host performance and the gut microbiota composition shaped by increasing antibiotic pollution under different food conditions is not clearly understood. In the present study, we used Daphnia magna as a model organism to investigate the interactive effects of diets (Chlorella with or without Microcystis) and antibiotics on its life history traits, gut microbiota alterations, and their relationship. The results showed that poor diet consumption by D. magna at low and high antibiotic concentrations reduced reproduction and survival. Under good diet conditions, the fitness was reduced only at a high antibiotic concentration. Under good diet conditions, high concentration of antibiotics reduced the abundance of Comamonadaceae and increased the abundance of Pseudomonadaceae, whereas under poor diet conditions, both low and high concentrations of antibiotics increased the abundance of Pseudomonadaceae. Performances of life history traits were positively correlated with an increased abundance of Comamonadaceae but were negatively correlated with increased Pseudomonadaceae abundance. The results of this study revealed the interactive effects of diet and antibiotics on D. magna fitness and correlations between bacterial abundance and life history traits, which has important implications for understanding the effects of pollutants on host-microbiota interactions through changes in phenotypes.


Assuntos
Microbioma Gastrointestinal , Traços de História de Vida , Animais , Antibacterianos , Chlorella , Daphnia , Dieta
9.
Viruses ; 12(2)2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31991772

RESUMO

The use of viral pathogens to control thepopulation size of pest insects has produced both successful and unsuccessful outcomes. Here, we investigate whether those biocontrol successes and failures can be explained by key ecological and evolutionary processes between hosts and pathogens. Specifically, we examine how heterogeneity inpathogen transmission, ecological and evolutionary tradeoffs, andpathogen diversity affect insect population density and thus successful control. Wefirst review theexisting literature and then use numerical simulations of mathematical models to further explore these processes. Our results show that thecontrol of insect densities using viruses depends strongly on theheterogeneity of virus transmission among insects. Overall, increased heterogeneity of transmission reduces theeffect of viruses on insect densities and increases thelong-term stability of insect populations. Lower equilibrium insect densities occur when transmission is heritable and when there is atradeoff between mean transmission and insect fecundity compared to when theheterogeneity of transmission arises from non-genetic sources. Thus, theheterogeneity of transmission is akey parameter that regulates thelong-term population dynamics of insects and their pathogens. Wealso show that both heterogeneity of transmission and life-history tradeoffs modulate characteristics of population dynamics such as thefrequency and intensity of ``boom--bust" population cycles. Furthermore, we show that because of life-history tradeoffs affecting thetransmission rate, theuse of multiple pathogen strains is more effective than theuse of asingle strain to control insect densities only when thepathogen strains differ considerably intheir transmission characteristics. By quantifying theeffects of ecology and evolution on population densities, we are able to offer recommendations to assess thelong-term effects of classical biocontrol.


Assuntos
Evolução Biológica , Interações Hospedeiro-Patógeno , Controle de Insetos , Insetos/fisiologia , Insetos/virologia , Controle Biológico de Vetores , Fenômenos Fisiológicos Virais , Animais , Deriva Genética , Insetos/genética , Traços de História de Vida , Modelos Biológicos , Modelos Estatísticos , Vírus/genética
10.
Insect Sci ; 27(2): 361-374, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30298557

RESUMO

Diet quality influences organismal fitness within and across generations. For herbivorous insects, the transgenerational effects of diet remain relatively underexplored. Using a 3 × 3 × 2 factorial experiment, we evaluated how N enrichment in parental diets of Neolema abbreviata (Larcordaire) (Coleoptera: Chrysomelidae), a biological control agent for Tradescantia fluminensis Vell. (Commelinaceae), may influence life history and performance of F1 and F2 offspring under reciprocal experiments. We found limited transgenerational effects of foliar nitrogen variability among life-history traits in both larvae and adults. Larval weight gain and mortality were responsive to parental diet contrary to feeding damage, pupal weight and duration taken to pupate. There were significant parental diet × test interactions in larval feeding damage, weight gain, pupal weight and time to pupation. Generally, offspring from parents under high N plants performed better even under low N test plants. Adult traits including oviposition selection, feeding weight and longevity did not respond to the effects of parental diet nor its interaction with test diet as was the case in the larval stage. However, the main effects of test diet were more important in determining adult performance in both generations suggesting limited sensitivity to parental diet in the adult stage. Our results show conflicting responses to parental diet between larvae and adults of the same generation among an insect species with both actively feeding larval and adult life stages. These transgenerational effects, or lack thereof, may have implications on the field performance of N. abbrevita under heterogeneous nutritional landscapes.


Assuntos
Besouros , Dieta , Herbivoria , Traços de História de Vida , Animais , Feminino , Larva/crescimento & desenvolvimento , Masculino , Nitrogênio , Oviposição
11.
Insect Sci ; 27(2): 317-335, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30381878

RESUMO

Drosophila suzukii is an invasive pest causing severe damages to a large panel of cultivated crops. To facilitate its biocontrol with strategies such as sterile or incompatible insect techniques, D. suzukii must be mass-produced and then stored and transported under low temperature. Prolonged cold exposure induces chill injuries that can be mitigated if the cold period is interrupted with short warming intervals, referred to as fluctuating thermal regimes (FTR). In this study, we tested how to optimally use FTR to extend the shelf life of D. suzukii under cold storage. Several FTR parameters were assessed: temperature (15, 20, 25 °C), duration (0.5, 1, 2, 3 h), and frequency (every 12, 24, 36, 48 h) of warming intervals, in two wild-type lines and in two developmental stages (pupae and adults). Generally, FTR improved cold storage tolerance with respect to constant low temperatures (CLT). Cold mortality was lower when recovery temperature was 20 °C or higher, when duration was 2 h per day or longer, and when warming interruptions occurred frequently (every 12 or 24 h). Applying an optimized FTR protocol to adults greatly reduced cold mortality over long-term storage (up to 130 d). Consequences of FTR on fitness-related traits were also investigated. For adults, poststorage survival was unaffected by FTR, as was the case for female fecundity and male mating capacity. On the other hand, when cold storage occurred at pupal stage, poststorage survival and male mating capacity were altered under CLT, but not under FTR. After storage of pupae, female fecundity was lower under FTR compared to CLT, suggesting an energy trade-off between repair of chill damages and egg production. This study provides detailed information on the application and optimization of an FTR-based protocol for cold storage of D. suzukii that could be useful for the biocontrol of this pest.


Assuntos
Resposta ao Choque Frio , Drosophila/fisiologia , Traços de História de Vida , Animais , Feminino , Fertilidade , Masculino , Comportamento Sexual Animal
12.
Proc Natl Acad Sci U S A ; 117(3): 1580-1586, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31848238

RESUMO

Consumers face numerous risks that can be minimized by incorporating different life-history strategies. How much and when a consumer adds to its energetic reserves or invests in reproduction are key behavioral and physiological adaptations that structure communities. Here we develop a theoretical framework that explicitly accounts for stochastic fluctuations of an individual consumer's energetic reserves while foraging and reproducing on a landscape with resources that range from uniformly distributed to highly clustered. First, we show that the selection of alternative life histories depends on both the mean and variance of resource availability, where depleted and more stochastic environments promote investment in each reproductive event at the expense of future fitness as well as more investment per offspring. We then show that if resource variance scales with body size due to landscape clustering, consumers that forage for clustered foods are susceptible to strong Allee effects, increasing extinction risk. Finally, we show that the proposed relationship between resource distributions, consumer body size, and emergent demographic risk offers key ecological insights into the evolution of large-bodied grazing herbivores from small-bodied browsing ancestors.


Assuntos
Evolução Biológica , Herbivoria/fisiologia , Traços de História de Vida , Reprodução , Adaptação Fisiológica , Animais , Tamanho Corporal , Aptidão Genética , Modelos Biológicos
13.
Water Res ; 168: 115165, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614238

RESUMO

Despite the concern about anthropogenic heavy metal accumulation, there remain few multi-level ecotoxicological studies to evaluate their effects in fluvial ecosystems. The toxicity of field-collected sediments exhibiting a gradient of heavy metal contamination (Cd, Pb, and Zn) was assessed in Chironomus riparius. For this purpose, larvae were exposed throughout their entire life cycle to these sediments, and toxic effects were measured at different levels of biological organization, from the molecular (lipidomic analysis and transcriptional profile) to the whole organism response (respiration rate, shape markers, and emergence rate). Alterations in the activity of relevant genes, as well as an increase of storage lipids and decrease in membrane fluidity, were detected in larvae exposed to the most contaminated sediments. Moreover, reduced larval and adult mass, decrease of larval respiration rate, and delayed emergence were observed, along with increased mentum and mandible size in larvae and decreased wing loading in adults. This study points out the deleterious effects of heavy metal exposure at various levels of biological organization and provides some clues regarding the mode of toxic action. This integrative approach provides new insights into the multi-level effects on aquatic insects exposed to heavy metal mixtures in field sediments, providing useful tools for ecological risk assessment in freshwater ecosystems.


Assuntos
Chironomidae , Traços de História de Vida , Metais Pesados , Poluentes Químicos da Água , Animais , Ecossistema , Sedimentos Geológicos , Larva , Lipídeos
14.
PLoS One ; 14(12): e0226519, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31856200

RESUMO

Resource availability during development shapes not only adult phenotype but also the phenotype of subsequent offspring. When resources are absent and periods of starvation occur in early life, such developmental stress often influences key life-history traits in a way that benefits individuals and their offspring when facing further bouts of starvation. Here we investigated the impacts of different starvation regimes during larval development on life-history traits and measures of consumption in the turnip sawfly, Athalia rosae (Hymenoptera: Tenthredinidae). We then assessed whether offspring of starved and non-starved parents differed in their own life-history if reared in conditions that either matched that of their parents or were a mismatch. Early life starvation effects were more pronounced within than across generations in A. rosae, with negative impacts on adult body mass and increases in developmental time, but no effects on adult longevity in either generation. We found some evidence of higher growth rates in larvae having experienced starvation, although this did not ameliorate the overall negative effect of larval starvation on adult size. However, further work is necessary to disentangle the effects of larval size and instar from those of starvation treatment. Finally, we found weak evidence for transgenerational effects on larval growth, with intra-generational larval starvation experience being more decisive for life-history traits. Our study demonstrates that intra-generational effects of starvation are stronger than transgenerational effects on life-history traits and consumption measures in A. rosae.


Assuntos
Himenópteros/fisiologia , Traços de História de Vida , Inanição , Animais , Feminino , Masculino , Fatores de Tempo
15.
Nat Commun ; 10(1): 5757, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848330

RESUMO

Tradeoffs affect resource allocation during development and result in fitness consequences that drive the evolution of life history strategies. Yet despite their importance, we know little about the mechanisms underlying life history tradeoffs. Many species of Colias butterflies exhibit an alternative life history strategy (ALHS) where females divert resources from wing pigment synthesis to reproductive and somatic development. Due to this reallocation, a wing color polymorphism is associated with the ALHS: either yellow/orange or white. Here we map the locus associated with this ALHS in Colias crocea to a transposable element insertion located downstream of the Colias homolog of BarH-1, a homeobox transcription factor. Using CRISPR/Cas9 gene editing, antibody staining, and electron microscopy we find white-specific expression of BarH-1 suppresses the formation of pigment granules in wing scales and gives rise to white wing color. Lipid and transcriptome analyses reveal physiological differences associated with the ALHS. Together, these findings characterize a mechanism for a female-limited ALHS.


Assuntos
Borboletas/fisiologia , Elementos de DNA Transponíveis/genética , Loci Gênicos , Proteínas de Homeodomínio/genética , Traços de História de Vida , Animais , Sistemas CRISPR-Cas/genética , Cor , Feminino , Edição de Genes/métodos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Masculino , Pigmentação/genética , Pigmentos Biológicos/biossíntese , Reprodução/genética , Fatores Sexuais , Sequenciamento Completo do Genoma , Asas de Animais/metabolismo , Asas de Animais/ultraestrutura
16.
Plant Sci ; 289: 110258, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31623797

RESUMO

High temperature stress (HTS) is one of the most crucial factors that limits plant growth and development, and reduces crop yields worldwide. Cool-season crops, particularly the legumes, are severely affected by increasing ambient temperature associated with global climate change. We characterized the HTS-induced modulations of morpho-physicochemical traits and gene expression of several chickpea genotypes and the metabolic profile of the tolerant cultivar. Higher water use efficiency and photosynthetic capacity, minimal membrane lipid peroxidation in conjunction with increased abundance of osmolytes and secondary metabolites depicted thermotolerance of ICC 1205. The adaptive responses were accompanied by high transcript abundance of heat shock proteins and antioxidant enzymes. To integrate stress-responsive signalling and metabolic networks, the HTS-induced physicochemical analysis was further extended to metabolite profiling of the thermotolerant cultivar. The screening of the metabolome landscape led to the identification of 49 HTS-responsive metabolites that include polycarboxylic acid, sugar acids, sugar alcohols and amino acids which might confer thermotolerance in chickpea. The present study, to our knowledge, is the most comprehensive of its kind in dissecting cultivar-specific differential adaptive responses to HTS in chickpea, which might potentiate the identification of genetic traits extendible to improvement of thermotolerance of crops.


Assuntos
Cicer/fisiologia , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/fisiologia , Traços de História de Vida , Cicer/genética , Genótipo , Temperatura Alta/efeitos adversos , Metaboloma , Estresse Fisiológico/genética
17.
J Plant Res ; 132(6): 719-721, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31595362

RESUMO

The past quarter-century has witnessed a revolution in our understanding of the phylogenetics, systematics, and ecology of pteridophytes (ferns and lycophytes), particularly due to the rapid accumulation of plastid sequence data and a renewed interest in the ecology of the sexual phase of the life cycle. We here compile 19 papers recently published in the Journal of Plant Research dealing with the biology of pteridophytes, grouped into six categories: (1) breeding systems, (2) species complexes and polyploidization, (3) fossil taxa, (4) gametophyte ecology, (5) systematics, (6) biodiversity. We hope this collection of papers will be of value to researchers interested in this fascinating group of plants.


Assuntos
Evolução Biológica , Gleiquênias/fisiologia , Traços de História de Vida , Lycopodiaceae/fisiologia , Selaginellaceae/fisiologia , Evolução Molecular , Gleiquênias/classificação , Gleiquênias/genética , Lycopodiaceae/classificação , Lycopodiaceae/genética , Selaginellaceae/classificação , Selaginellaceae/genética
18.
J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31612945

RESUMO

The green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), is an important agricultural pest with a wide range of host plants. To study effects of host species on the life history traits of M. persicae, aphids were individually reared on five host plants: Brassica campestris L. (Brassicales: Brassicaceae), Capsicum annuum L. (Tubiflorae: Solanaceae), Nicotiana tabacum L. (Tubiflorae: Solanaceae), Raphanus sativus L. (Brassicales: Brassicaceae), and Vicia faba L. (Rosales: Leguminosae). TWOSEX-MSchart software was used for the statistical analysis according to the age-stage, two-sex life table theory. The results showed that the shortest preadult stage and adult/total prereproductive period of M. persicae were 6.48, 0.19, and 6.67 d on V. faba, respectively. While the adult and total longevity of M. persicae on R. sativus (25.00 and 31.62 d) and N. tabacum (24.40 and 30.56 d) were significantly longer than that on the other three hosts, as was the reproductive period. The fecundity of M. persicae on R. sativus (80.83 nymphs per female), N. tabacum (71.72 nymphs per female), and V. faba (70.39 nymphs per female) was also greater than that on B. campestris and C. annuum. It was demonstrated that V. faba, R. sativus, and N. tabacum were more suitable plants for the growth of M. persicae exhibiting a shorter preadult stage, longer longevity, and greater fecundity than the remaining two species, as confirmed by the higher intrinsic rate of increase and net reproductive rate.


Assuntos
Afídeos/fisiologia , Cadeia Alimentar , Herbivoria , Traços de História de Vida , Animais , Afídeos/crescimento & desenvolvimento , Feminino , Longevidade , Magnoliopsida/fisiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Crescimento Demográfico
19.
Exp Appl Acarol ; 79(1): 35-46, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31564008

RESUMO

The brown citrus rust mite, Tegolophus brunneus Flechtmann (Acari: Eriophyidae), causes citrus rust, as does Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae). As the citrus rust damage has intensified in recent years and T. brunneus has been reported in high population levels in several regions of Brazil, this mite has caused concern to growers and technicians. Because T. brunneus has been little studied and its bioecological characteristics are unknown, this study investigated the biological and demographic parameters of T. brunneus on citrus fruits under laboratory conditions. Our results showed that the egg incubation period and viability were 3.0 and 94.5%, respectively. The larval and nymphal stage durations were 1.1 and 2.8 days, respectively. The development time of the immature stage was 6.9 days, with 92.3% survival. When females and males were maintained together, the sex ratio of offspring was 0.7; virgin females produced only males. The pre-oviposition (from adult emergence to the first egg) and total pre-oviposition (egg-to-egg) periods were 1.6 and 8.5 days, respectively. Fecundity was 8.5 eggs, and female and male longevities were 13.2 and 11.4 days, respectively. The estimate of demographic parameters indicated that the Ro and T of T. brunneus were 6.45 offspring and 13.0 days, and r and λ were 0.142 and 1.153 day-1, respectively. These results suggest that T. brunneus has high growth potential on citrus trees. Therefore, management strategies may be required to reduce the population levels and damage caused by T. brunneus in citrus groves.


Assuntos
Traços de História de Vida , Ácaros/fisiologia , Oviposição , Animais , Citrus , Demografia , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ácaros/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Dinâmica Populacional , Reprodução
20.
Mol Biol Evol ; 36(12): 2778-2789, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504759

RESUMO

Most eukaryotes inherit their mitochondria from only one of their parents. When there are different sexes, it is almost always the maternal mitochondria that are transmitted. Indeed, maternal uniparental inheritance has been reported for the brown alga Ectocarpus but we show in this study that different strains of Ectocarpus can exhibit different patterns of inheritance: Ectocarpus siliculosus strains showed maternal uniparental inheritance, as expected, but crosses using different Ectocarpus species 7 strains exhibited either paternal uniparental inheritance or an unusual pattern of transmission where progeny inherited either maternal or paternal mitochondria, but not both. A possible correlation between the pattern of mitochondrial inheritance and male gamete parthenogenesis was investigated. Moreover, in contrast to observations in the green lineage, we did not detect any change in the pattern of mitochondrial inheritance in mutant strains affected in life cycle progression. Finally, an analysis of field-isolated strains provided evidence of mitochondrial genome recombination in both Ectocarpus species.


Assuntos
Genes Mitocondriais , Feófitas/genética , Genoma Mitocondrial , Traços de História de Vida , Partenogênese/genética , Recombinação Genética
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