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1.
New Phytol ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39155785

RESUMO

Strengthening future food security through the application of unsustainable levels of inorganic nitrogen (N) fertilizers to crop fields may exacerbate environmental damage. Coordination of N-use efficiency (NUE) and plant growth is, therefore, crucial for sustainable agriculture. Auxin plays pivotal roles in developmental and signaling responses that affect NUE. Hence, a better understanding of these processes provides great potential to improve crop NUE. This review summarizes the effects of auxin on N-related and root developmental processes that either directly or indirectly affect NUE in the model plant Arabidopsis and major crop species to highlight the potential of fostering sustainable agricultural development in the future through modulating auxin-related processes.

2.
Animals (Basel) ; 14(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39123670

RESUMO

Reproductive traits in dairy cattle are crucial for herd productivity and profitability. This study investigates the influence of relatedness to high immune response (HIR) Immunity+ sires on reproductive performance indicators in Polish Holstein-Friesian cows. A total of 5094 cows were analyzed, categorized based on their relatedness to HIR Immunity+ sires, and assessed for various reproductive parameters, including age at first insemination, gestation length, days open, calving interval, and calving ease. The results showed that the level of relatedness to HIR Immunity+ sires influenced certain reproductive traits, such as service period, gestation length, and age at first and second calving. Additionally, cows related to HIR Immunity+ sires exhibited a higher frequency of twin pregnancies and more complicated births. While some benefits were observed in certain reproductive traits among cows related to HIR Immunity+ sires, such as reduced age at first insemination and shortened gestation length, the overall impact on reproductive efficiency remains inconclusive. Further studies are needed to fully elucidate the effects of using semen from HIR Immunity+ sires on reproductive performance in dairy cattle.

3.
Anim Biotechnol ; 35(1): 2362677, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38860914

RESUMO

Ruminant animals, such as dairy cattle, produce CH4, which contributes to global warming emissions and reduces dietary energy for the cows. While the carbon foot print of milk production varies based on production systems, milk yield and farm management practices, enteric fermentation, and manure management are major contributors togreenhouse gas emissions from dairy cattle. Recent emerging evidence has revealed the existence of genetic variation for CH4 emission traits among dairy cattle, suggests their potential inclusion in breeding goals and genetic selection programs. Advancements in high-throughput sequencing technologies and analytical techniques have enabled the identification of potential metabolic biomarkers, candidate genes, and SNPs linked to methane emissions. Indeed, this review critically examines our current understanding of carbon foot print in milk production, major emission sources, rumen microbial community and enteric fermentation, and the genetic architecture of methane emission traits in dairy cattle. It also emphasizes important implications for breeding strategies aimed at halting methane emissions through selective breeding, microbiome driven breeding, breeding for feed efficiency, and breeding by gene editing.


Assuntos
Cruzamento , Metano , Animais , Metano/metabolismo , Bovinos/genética , Indústria de Laticínios/métodos , Feminino
4.
BMC Plant Biol ; 24(1): 462, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802731

RESUMO

In this comprehensive genome-wide study, we identified and classified 83 Xylanase Inhibitor Protein (XIP) genes in wheat, grouped into five distinct categories, to enhance understanding of wheat's resistance to Fusarium head blight (FHB), a significant fungal threat to global wheat production. Our analysis reveals the unique distribution of XIP genes across wheat chromosomes, particularly at terminal regions, suggesting their role in the evolutionary expansion of the gene family. Several XIP genes lack signal peptides, indicating potential alternative secretion pathways that could be pivotal in plant defense against FHB. The study also uncovers the sequence homology between XIPs and chitinases, hinting at a functional diversification within the XIP gene family. Additionally, the research explores the association of XIP genes with plant immune mechanisms, particularly their linkage with plant hormone signaling pathways like abscisic acid and jasmonic acid. XIP-7A3, in particular, demonstrates a significant increase in expression upon FHB infection, highlighting its potential as a key candidate gene for enhancing wheat's resistance to this disease. This research not only enriches our understanding of the XIP gene family in wheat but also provides a foundation for future investigations into their role in developing FHB-resistant wheat cultivars. The findings offer significant implications for wheat genomics and breeding, contributing to the development of more resilient crops against fungal diseases.


Assuntos
Resistência à Doença , Fusarium , Doenças das Plantas , Proteínas de Plantas , Triticum , Triticum/genética , Triticum/microbiologia , Triticum/imunologia , Fusarium/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Imunidade Vegetal/genética , Estudo de Associação Genômica Ampla , Genes de Plantas , Genoma de Planta , Filogenia
5.
J Anim Breed Genet ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38745529

RESUMO

In the past, small population sizes and unequal ancestor contributions have resulted in high inbreeding rates (ΔF) in the Friesian horse. Two decades ago, the studbook implemented a mating quota and started publishing individual kinships and reduced ΔF below 1% per generation. However, since then, the breeding population size has decreased and this raises the question whether current breeding strategies are sufficient to keep ΔF below desired rates. The aim of this study was to (1) reflect on past inbreeding trends and their main determinants, using pedigree analysis and (2) evaluate the effectiveness of the current and additional breeding strategies using stochastic simulations. We estimated the current ΔF (2013-2022) at 0.72% per generation. While the total contribution of the top 10 sires to the number of offspring per year has decreased from 75% in 1980 to 35% in 2022, this was mainly due to an increased number of approved studbook sires, and not due to more equalized contributions among sires. Of the simulated breeding strategies, selecting only breeding stallions with a below average mean kinship (i.e., "mean kinship selection") was most effective to decrease ΔF (from 0.66% to 0.33%). Increasing the number of breeding sires only had an effect when also a mating quota was applied. However, its effect remained limited. For example, a ~1.5 fold increase, combined with a mating quota of 80 offspring per sire per year, reduced ΔF from 0.55% to 0.51%. When increasing the number of breeding mares, a practically unfeasible large increase was needed for a meaningful reduction in ΔF (e.g. twice as many mares were needed to reduce ΔF from 0.66% to 0.56%). Stratified mating quotas, a novel approach in which we assigned each sire a mating quota (of 60, 80, 100 or 120 offspring per year) based on its mean kinship to recently born foals, resulted in a lower ΔF (0.43%) than a general mating quota of 90 offspring per sire per year (0.55%). Overall, while the current ΔF is below 1%, we recommend to implement additional strategies to further reduce ΔF below 0.5% in the Friesian horse population. For this breed and similar populations, we recommend to focus on breeding strategies based on kinship levels to effectively reduce ΔF.

6.
Plants (Basel) ; 13(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38674477

RESUMO

This five-year study (2016-2021) across diverse Moroccan agro-climatic zones investigated genotype by environment (G × E) interactions in wheat, focusing on variations in agronomic traits and quality attributes such as protein and gluten content. Significant environmental effects were observed on key traits, like yield, thousand kernel weight (TKW), and spikes per square meter (Spk/m2), highlighting environmental factors' role in wheat yield variability. In the Tassaout (TST) location, notable genotypic effects emerged for traits like biomass, underscoring genetic factors' importance in specific contexts, while in Sidi El Aidi (SEA) and Marchouch (MCH), genotypic effects on yield and its components were predominantly absent, indicating a more substantial environmental influence. These findings illustrate the complexity of G × E interactions and the need for breeding strategies considering genetic potential and environmental adaptability, especially given the trade-offs between yield enhancement and quality maintenance. Insights from the biplot and heatmap analyses enhanced the understanding of genotypes' dynamic interactions with environmental factors, establishing a basis for strategic genotype selection and management to optimize wheat yield and quality. This research contributes to sustainable wheat breeding in Morocco, aligning with global efforts to adapt wheat breeding strategies to changing climatic conditions.

7.
Heliyon ; 10(8): e29095, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38655336

RESUMO

This working paper reviews the research and development in genetic improvement and breeding strategies of Bonga, Menz, Afar and Horro sheep in Ethiopia. This review aims to provide structured information regarding the Ethiopian indigenous sheep breeds (Bonga, Afar, Menz, and Horro) breeding programs and its progress. Genetic diversity is an essential element for genetic improvement, preserving populations, evaluation and adapting to variable environmental situations. Sustainable breeding techniques and sensible use of indigenous breed have been developed as result of recent research approaches to the conservation of sheep genetic resources. However, there is still growing interest of the government and of farmers in different breeding program to improve indigenous sheep breeds. There is no comprehensive study showing the performance of indigenous sheep breeds (Bonga, Afar, Menz, and Horro) genetic improvement under different breeding program and its progress, both biological and economic, to substantiate the argument on the benefit of different breeding programs for smallholders farmers. Programs for the sheep breeds Menz, Afar, Horro, and Bonga have now been developed at the community level. The idea behind the nucleus breeding program is to develop elite breeding animals by gathering the finest male and female breeding participants from the population in one central location. The first stage in creating a breeding program is defining the breeding goals. Planning breeding programs requires a thorough grasp of the farmers' (beneficiaries') breeding goals and production objectives. Therefore, this review makes it evident that numerous instruments and techniques, including choice experiments, participatory rural assessment procedures, and rating animals from flocks, have been used to define and ascertain the breeding aim of Afar, Horro, Bonga and Menz sheep breeds in Ethiopia.

8.
Planta ; 259(5): 123, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622376

RESUMO

MAIN CONCLUSION: Pigeonpea has potential to foster sustainable agriculture and resilience in evolving climate change; understanding bio-physiological and molecular mechanisms of heat and drought stress tolerance is imperative to developing resilience cultivars. Pigeonpea is an important legume crop that has potential resilience in the face of evolving climate scenarios. However, compared to other legumes, there has been limited research on abiotic stress tolerance in pigeonpea, particularly towards drought stress (DS) and heat stress (HS). To address this gap, this review delves into the genetic, physiological, and molecular mechanisms that govern pigeonpea's response to DS and HS. It emphasizes the need to understand how this crop combats these stresses and exhibits different types of tolerance and adaptation mechanisms through component traits. The current article provides a comprehensive overview of the complex interplay of factors contributing to the resilience of pigeonpea under adverse environmental conditions. Furthermore, the review synthesizes information on major breeding techniques, encompassing both conventional methods and modern molecular omics-assisted tools and techniques. It highlights the potential of genomics and phenomics tools and their pivotal role in enhancing adaptability and resilience in pigeonpea. Despite the progress made in genomics, phenomics and big data analytics, the complexity of drought and heat tolerance in pigeonpea necessitate continuous exploration at multi-omic levels. High-throughput phenotyping (HTP) is crucial for gaining insights into perplexed interactions among genotype, environment, and management practices (GxExM). Thus, integration of advanced technologies in breeding programs is critical for developing pigeonpea varieties that can withstand the challenges posed by climate change. This review is expected to serve as a valuable resource for researchers, providing a deeper understanding of the mechanisms underlying abiotic stress tolerance in pigeonpea and offering insights into modern breeding strategies that can contribute to the development of resilient varieties suited for changing environmental conditions.


Assuntos
Secas , Fabaceae , Melhoramento Vegetal , Fabaceae/genética , Genômica/métodos , Resposta ao Choque Térmico
9.
J Appl Genet ; 65(3): 419-428, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38355922

RESUMO

Genetic information of bean seed traits can be an immense help to the breeder in selection of suitable genotypes and the appropriate breeding strategies. Therefore, the investigation aims to assess the genetic variability and to elucidate the genetic analysis of seed dietary fibre, carbohydrate, seed calcium and phosphorus contents of Phaseolus vulgaris in the high Guinean Savannah zone conditions. 5 × 5 half-diallel crosses of these traits were conducted in randomized complete block design with three replications. Results revealed high differences between five lines beans (p < 0.05), suggesting the sufficient genetic diversity for these traits. High broad sense heritability values were recorded for seed dietary fibre, carbohydrate and seed calcium content, attesting a strong implication of the genetic factors in the control of these traits; thereby, these traits can be improved through regular selection. The ratio GCA/SCA was greater than unity only for seed phosphorus content. It indicates the prevalence of additive gene effect in the involvement of the genetic control for this trait. The combining ability analysis revealed highly significant differences between parental GCA effects and F1 cross SCA effects. The PB, BI, CT and PR lines beans will prove useful in common bean breeding programmes as donor genotypes, in the development of bean genetic resources for betterment improvement of nutritional traits.


Assuntos
Fibras na Dieta , Genótipo , Phaseolus , Fósforo , Sementes , Phaseolus/genética , Sementes/genética , Sementes/química , Fósforo/análise , Fósforo/metabolismo , Fibras na Dieta/análise , Cálcio/análise , Cálcio/metabolismo , Variação Genética , Melhoramento Vegetal , Cruzamentos Genéticos , Fenótipo
10.
Mol Biol Rep ; 50(12): 10509-10524, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37921982

RESUMO

The focus is now on harnessing energy from green sources through sustainable technology to minimize environmental pollution. Several crop residues including rice and wheat straw are having enormous potential to be used as lignocellulosic source material for bioenergy production. The lignocellulosic feedstock is primarily composed of cellulose, hemicellulose, and lignin cell wall polymers. The hemicellulose and lignin polymers induce crosslinks in the cell wall, by firmly associating with cellulose microfibrils, and thereby, denying considerable access of cellulose to cellulase enzymes. This issue has been addressed by various researchers through downregulating several genes associated in monolignol biosynthesis in Arabidopsis, Poplar, Rice and Switchgrass to increase ethanol recovery. Similarly, xylan biosynthetic genes are also targeted to genetically culminate its accumulation in the secondary cell walls. Regulation of cellulose synthases (CesA) proves to be an effective tool in addressing the negative impact of these two factors. Modification in the expression of cellulose synthase aids in reducing cellulose crystallinity as well as polymerisation degree which in turn increases ethanol recovery. The engineered bioenergy crops and various fungal strains with state of art biomass processing techniques presents the most recent integrative biotechnology model for cost effective green fuels generation along with production of key value-added products with minuscule disturbances in the environment. Plant breeding strategies utilizing the existing variability for biomass traits will be key in developing dual purpose varieties. For this purpose, reorientation of conventional breeding techniques for incorporating useful biomass traits will be effective.


Assuntos
Arabidopsis , Oryza , Lignina/metabolismo , Melhoramento Vegetal , Celulose/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Polímeros , Oryza/genética , Oryza/metabolismo , Arabidopsis/metabolismo , Etanol/metabolismo , Biomassa
11.
Zoology (Jena) ; 159: 126104, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37515906

RESUMO

Animal reproductive success implies the performance of several behaviours, such as courting, mate searching, copulation, offspring production and care. These behaviours usually have high energetic and ecological costs. Therefore, to maximise their reproductive success, animals should make choices throughout their lives, such as deciding how much energy to invest in different activities, according to their conditions and needs. In temperate estuaries, the fiddler crab L. uruguayensis has a short reproductive period, with two synchronous spawning events. Considering that reproductive behaviours incur high energetic cost to fiddler crabs, we estimated how this species manages its activity budget throughout the reproductive period, to quantify trade-offs between the time spent on reproductive behaviours versus time spent on other activities. By analysing videos of females and males recorded in the field at different moments of the reproductive period, we observed that pre-copulatory behaviours, such as female wandering and male waving were more intense at the beginning of the reproductive period, suggesting that most matings occurred before the first spawning event but not before the second one. The ecological conditions during the breeding season and the individual strategies adopted by males and females mostly determine when and how much time to spend on courtship behaviours, and behavioural plasticity can be expected whenever the conditions change. The strategy used by L. uruguayensis for energy management, females' ability to store male gametes and environmental temperatures might have been the main factors determining the relative time spent in courtship behaviours during the reproductive period.


Assuntos
Braquiúros , Feminino , Masculino , Animais , Estuários , Reprodução , Temperatura , Copulação , Comportamento Sexual Animal
12.
Plants (Basel) ; 12(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37299176

RESUMO

Soil salinity is a major abiotic stress in global agricultural productivity with an estimated 50% of arable land predicted to become salinized by 2050. Since most domesticated crops are glycophytes, they cannot be cultivated on salt soils. The use of beneficial microorganisms inhabiting the rhizosphere (PGPR) is a promising tool to alleviate salt stress in various crops and represents a strategy to increase agricultural productivity in salt soils. Increasing evidence underlines that PGPR affect plant physiological, biochemical, and molecular responses to salt stress. The mechanisms behind these phenomena include osmotic adjustment, modulation of the plant antioxidant system, ion homeostasis, modulation of the phytohormonal balance, increase in nutrient uptake, and the formation of biofilms. This review focuses on the recent literature regarding the molecular mechanisms that PGPR use to improve plant growth under salinity. In addition, very recent -OMICs approaches were reported, dissecting the role of PGPR in modulating plant genomes and epigenomes, opening up the possibility of combining the high genetic variations of plants with the action of PGPR for the selection of useful plant traits to cope with salt stress conditions.

13.
Animals (Basel) ; 13(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37174480

RESUMO

The brood reduction hypothesis, which explains asynchronous hatching in birds, as an adaptation that enables selective survival of older nestlings when availability of food is unpredictable. This study was conducted in order to determine whether the brood reduction hypothesis can explain asynchronous hatching in passerines. Infrared cameras were installed inside nest boxes where great tits (Parus major) were attempting to reproduce in order to determine whether the parents practiced selective feeding of older nestlings. According to the results of the study, no significant difference was observed between the hatching order and the average number of feedings per nestling. In addition, when examining the distribution of food according to hatching order over time, every 30 min, beginning at 9 a.m., selective distribution of food to older nestlings was not observed. In conclusion, use of the brood reduction hypothesis, which supports selective provision of beneficial feeding of older and larger nestlings, to explain the asynchronous hatching of passerines is problematic, thus conduct of future studies focusing on other hypotheses in order to explain the asynchronous hatching of this passerine bird will be necessary.

14.
Trends Plant Sci ; 28(10): 1178-1191, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37208203

RESUMO

Many newly created early maturing varieties exhibit poor stress resistance and low yield, whereas stress-resistant varieties are typically late maturing. For this reason, the polymerization of early maturity and other desired agronomic qualities requires overcoming the negative connection between early maturity, multi-resistance, and yield, which presents a formidable challenge in current breeding techniques. We review the most salient constraints of early maturity breeding in current crop planting practices and the molecular mechanisms of different maturation timeframes in diverse crops from their origin center to production areas. We explore current breeding tactics and the future direction of crop breeding and the issues that must be resolved to accomplish the polymerization of desirable traits in light of the current obstacles and limitations.


Assuntos
Produtos Agrícolas , Melhoramento Vegetal , Fenótipo , Produtos Agrícolas/genética , Agricultura
15.
Front Plant Sci ; 14: 1135237, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37025131

RESUMO

Phenolic acids and flavonoids are large groups of secondary metabolites ubiquitous in the plant kingdom. They are currently in the spotlight due to the numerous health benefits associated with their consumption, as well as for their vital roles in plant biological processes and in plant-environment interaction. Tomato, eggplant and pepper are in the top ten most consumed vegetables in the world, and their fruit accumulation profiles have been extensively characterized, showing substantial differences. A broad array of genetic and genomic tools has helped to identify QTLs and candidate genes associated with the fruit biosynthesis of phenolic acids and flavonoids. The aim of this review was to synthesize the available information making it easily available for researchers and breeders. The phenylpropanoid pathway is tightly regulated by structural genes, which are conserved across species, along with a complex network of regulatory elements like transcription factors, especially of MYB family, and cellular transporters. Moreover, phenolic compounds accumulate in tissue-specific and developmental-dependent ways, as different paths of the metabolic pathway are activated/deactivated along with fruit development. We retrieved 104 annotated putative orthologues encoding for key enzymes of the phenylpropanoid pathway in tomato (37), eggplant (29) and pepper (38) and compiled 267 QTLs (217 for tomato, 16 for eggplant and 34 for pepper) linked to fruit phenolic acids, flavonoids and total phenolics content. Combining molecular tools and genetic variability, through both conventional and genetic engineering strategies, is a feasible approach to improve phenolics content in tomato, eggplant and pepper. Finally, although the phenylpropanoid biosynthetic pathway has been well-studied in the Solanaceae, more research is needed on the identification of the candidate genes behind many QTLs, as well as their interactions with other QTLs and genes.

16.
New Phytol ; 237(4): 1100-1114, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36352520

RESUMO

Cotton's fundamental requirements for long periods of growth and specific seasonal temperatures limit the global arable areas that can be utilized to cultivate cotton. This constraint can be alleviated by breeding for early-maturing varieties. By delaying the sowing dates without impacting the boll-opening time, early-maturing varieties not only mitigate the yield losses brought on by unfavorable weathers in early spring and late autumn but also help reducing the competition between cotton and other crops for arable land, thereby optimizing the cropping system. This review presents studies and breeding efforts for early-maturing cotton, which efficiently pyramid early maturity, high-quality, multiresistance traits, and suitable plant architecture by leveraging pleiotropic genes. Attempts are also made to summarize our current understanding of the molecular mechanisms underlying early maturation, which involves many pathways such as epigenetic, circadian clock, and hormone signaling pathways. Moreover, new avenues and effective measures are proposed for fine-scale breeding of early-maturing crops to ensure the healthy development of the agricultural industry.


Assuntos
Agricultura , Melhoramento Vegetal , Fenótipo , Estações do Ano , Gossypium/genética
17.
Front Plant Sci ; 13: 844635, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35300006

RESUMO

Compared to sole crops, intercropping-especially of legumes and cereals-has great potential to improve crop yield and resource use efficiency, and can provide many other ecosystem services. However, the beneficial effects of intercrops are often greatly dependent on the end use as well as the specific species and genotypes being co-cultivated. In addition, intercropping imposes added complexity at different levels of the supply chain. While the need for developing crop genotypes for intercropping has long been recognized, most cultivars on the market are optimized for sole cropping and may not necessarily perform well in intercrops. This paper aims to place breeding targets for intercrop-adapted genotypes in a supply chain perspective. Three case studies of legumes and cereals intercropped for human consumption are used to identify desirable intercrop traits for actors across the supply chains, many of which are not targeted by traditional breeding for sole crops, including certain seed attributes, and some of which do not fit traditional breeding schemes, such as breeding for synchronized maturity and species synergies. Incorporating these traits into intercrop breeding could significantly reduce complexity along the supply chain. It is concluded that the widespread adoption and integration of intercrops will only be successful through the inclusion and collaboration of all supply chain actors, the application of breeding approaches that take into account the complexity of intercrop supply chains, and the implementation of diversification strategies in every process from field to fork.

18.
Curr Zool ; 68(1): 41-55, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35169628

RESUMO

Color polymorphisms are widely studied to identify the mechanisms responsible for the origin and maintenance of phenotypic variability in nature. Two of the mechanisms of balancing selection currently thought to explain the long-term persistence of polymorphisms are the evolution of alternative phenotypic optima through correlational selection on suites of traits including color and heterosis. Both of these mechanisms can generate differences in offspring viability and fitness arising from different morph combinations. Here, we examined the effect of parental morph combination on fertilization success, embryonic viability, newborn quality, antipredator, and foraging behavior, as well as inter-annual survival by conducting controlled matings in a polymorphic lacertid Podarcis muralis, where color morphs are frequently assumed to reflect alternative phenotypic optima (e.g., alternative reproductive strategies). Juveniles were kept in outdoor tubs for a year in order to study inter-annual growth, survival, and morph inheritance. In agreement with a previous genome-wide association analysis, morph frequencies in the year-old juveniles matched the frequencies expected if orange and yellow expressions depended on recessive homozygosity at 2 separate loci. Our findings also agree with previous literature reporting higher reproductive output of heavy females and the higher overall viability of heavy newborn lizards, but we found no evidence for the existence of alternative breeding investment strategies in female morphs, or morph-combination effects on offspring viability and behavior. We conclude that inter-morph breeding remains entirely viable and genetic incompatibilities are of little significance for the maintenance of discrete color morphs in P. muralis from the Pyrenees.

19.
Evolution ; 76(2): 373-384, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34854483

RESUMO

The hidden-state speciation and extinction (HiSSE) model helps avoid spurious results when testing whether a character affects diversification rates. However, care must be taken to optimally analyze models and interpret results. Recently, Tonini et al. (TEA hereafter) studied anuran (frog and toad) diversification with HiSSE methods. They concluded that their focal state, breeding in phytotelmata, increases net diversification rates. Yet this conclusion is counterintuitive, because the state that purportedly increases net diversification rates is 14 times rarer among species than the alternative. Herein, I revisit TEA's analyses and demonstrate problems with inferring model likelihoods, conducting post hoc tests, and interpreting results. I also reevaluate their top models and find that diverse strategies are necessary to reach the parameter values that maximize each model's likelihood. In contrast to TEA, I find no support for an effect of phytotelm breeding on net diversification rates in Neotropical anurans. In particular, even though the most highly supported models include the focal character, averaging parameter estimates over hidden states shows that the focal character does not influence diversification rates. Finally, I suggest ways to better analyze and interpret complex diversification models-both state-dependent and beyond-for future studies in other organisms.


Assuntos
Extinção Biológica , Especiação Genética , Animais , Anuros/genética , Filogenia , Melhoramento Vegetal
20.
Environ Microbiome ; 16(1): 20, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711269

RESUMO

BACKGROUND: Bacteria associated with plants can enhance the plants' growth and resistance against phytopathogens. Today, growers aim to reduce the use of mineral fertilizers and pesticides. Since phytopathogens cause severe yield losses in crop production systems, biological alternatives gain more attention. Plant and also seed endophytes have the potential to influence the plant, especially seed-borne bacteria may express their beneficiary impact at initial plant developmental stages. In the current study, we assessed the endophytic seed microbiome of seven genetically diverse barley accessions by 16S rRNA gene amplicon sequencing and verified the in vitro plant beneficial potential of isolated seed endophytes. Furthermore, we investigated the impact of the barley genotype and its seed microbiome on the rhizosphere microbiome at an early growth stage by 16S rRNA gene amplicon sequencing. RESULTS: The plant genotype displayed a significant impact on the microbiota in both barley seed and rhizosphere. Consequently, the microbial alpha- and beta-diversity of the endophytic seed microbiome was highly influenced by the genotype. Interestingly, no correlation was observed between the endophytic seed microbiome and the single nucleotide polymorphisms of the seven genotypes. Unclassified members of Enterobacteriaceae were by far most dominant. Other abundant genera in the seed microbiome belonged to Curtobacterium, Paenibacillus, Pantoea, Sanguibacter and Saccharibacillus. Endophytes isolated from barley seeds were affiliated to dominant genera of the core seed microbiome, based on their 16S rRNA gene sequence. Most of these endophytic isolates produced in vitro plant beneficial secondary metabolites known to induce plant resistance. CONCLUSION: Although barley accessions representing high genetic diversity displayed a genotype-dependent endophytic seed microbiome, a core seed microbiome with high relative abundances was identified. Endophytic isolates were affiliated to members of the core seed microbiome and many of them showed plant beneficial properties. We propose therefore that new breeding strategies should consider genotypes with high abundance of beneficial microbes.

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