Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Plants (Basel) ; 12(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37514262

RESUMO

Somatic embryogenesis (SE) in conifers is usually characterized as a multi-step process starting with the development of proembryogenic cell masses and followed by histodifferentiation, somatic embryo development, maturation, desiccation, and plant regeneration. Our current understanding of conifers' SE is mainly derived from studies using Pinaceae species as a model. However, the evolutionary relationships between conifers are not clear. Some hypotheses consider conifers as a paraphyletic group and Gnetales as a closely related clade. In this review, we used an integrated approach in order to cover the advances in knowledge on SE in conifers and Gnetales, discussing the state-of-the-art and shedding light on similarities and current bottlenecks. With this approach, we expect to be able to better understand the integration of these clades within current studies on SE. Finally, the points discussed raise an intriguing question: are non-Pinaceae conifers less prone to expressing embryogenic competence and generating somatic embryos as compared to Pinaceae species? The development of fundamental studies focused on this morphogenetic route in the coming years could be the key to finding a higher number of points in common between these species, allowing the success of the SE of one species to positively affect the success of another.

2.
Phytochemistry ; 203: 113350, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35973612

RESUMO

Defense-related metabolome traits in pine species after infestation by Sirex noctilio are largely unknown, despite, in most cases, trees being overwhelmed. Using LC-MS-based untargeted metabolomics, we revealed the systemic metabolic changes induced by this insect in 14-year-old Pinus radiata trees, the most affected species worldwide. An immediate metabolome alteration was expressed in needles after infestation, including the up-regulation of flavonols, flavan-3-ols, oxyneolignans, auxins, proline, and tryptophan, among others. The flavan-3-ols (catechin and procyanidin B1) suggested a rapidly induced photoprotection mechanism aided by diverting proline as an alternative substrate for respiration to compensate for the progressive chlorosis that degrades photosystems. Meanwhile, glutathione, glutamate, and ascorbate levels significantly dropped in needles, which may indicate the critical oxidative stress that trees had to face since the onset of the infestation. They were not fully replenished after long-term infestation, and redox homeostasis was probably not achieved, compromising tree survival. Nevertheless, a huge auxins overexpression detected in needles throughout the infestation may reflect tolerance against the premature senescence caused by the woodwasp venom. In contrast, the metabolome of wood tissues remained initially unchanged, although it seems to collapse after three months. Overall, the metabolomics strategy adopted in this work evidenced its usefulness in uncovering the fundamental roles of plants' chemical defense that govern interactions with specific stressors.


Assuntos
Catequina , Himenópteros , Pinus , Animais , Flavonóis , Glutamatos , Glutationa , Himenópteros/fisiologia , Ácidos Indolacéticos , Prolina , Árvores , Triptofano
3.
Am J Bot ; 109(5): 706-726, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35526278

RESUMO

PREMISE: Accurate species delimitation is essential for evolutionary biology, conservation, and biodiversity management. We studied species delimitation in North American pinyon pines, Pinus subsection Cembroides, a natural group with high levels of incomplete lineage sorting. METHODS: We used coalescent-based methods and multivariate analyses of low-copy number nuclear genes and nearly complete high-copy number plastomes generated with the Hyb-Seq method. The three coalescent-based species delimitation methods evaluated were the Generalized Mixed Yule Coalescent (GMYC), Poisson Tree Process (PTP), and Trinomial Distribution of Triplets (Tr2). We also measured admixture in populations with possible introgression. RESULTS: Our results show inconsistencies among GMYC, PTP, and Tr2. The single-locus based GMYC analysis of plastid DNA recovered a higher number of species (up to 24 entities, including singleton lineages and clusters) than PTP and the multi-locus coalescent approach. The PTP analysis identified 10 species whereas Tr2 recovered 13, which agreed closely with taxonomic treatments. CONCLUSIONS: We found that PTP and GMYC identified species with low levels of ILS and high morphological divergence (P. maximartinezii, P. pinceana, and P. rzedowskii). However, GMYC method oversplit species by identification of more divergent samples as singletons. Moreover, both PTP and GMYC were incapable of identifying some species that are readily identified morphologically. We suggest that the divergence times between lineages within North American pinyon pines are so disparate that GMYC results are unreliable. Results of the Tr2 method coincided well with previous delimitations based on morphology, DNA, geography, and secondary chemistry.


Assuntos
Núcleo Celular , Pinus , Núcleo Celular/genética , DNA , América do Norte , Filogenia , Pinus/genética
4.
Sci. agric ; 79(6): e20210092, 2022. mapa, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1347910

RESUMO

The species Pinus taeda is largely used in intensive silviculture worldwide. This species has propagation through seeds, which requires determining seeds viability for their commercialization. The germination test recommended for this species usually requires up to 63 days to provide results on the quality of freshly harvested seeds, delaying commercialization and favoring contamination during the conduction of the test. The authors of this study aimed to establish the developmental stages of P. taeda seedlings to determine a criterion for interpreting the germination test with greater speed and efficiency to obtain results. The seeds were sown in transparent plastic boxes on two sheets of blotting paper and placed in a germinator at 22 °C with constant lighting. Five morphological stages of seedling development were defined with daily counts of the number of normal seedlings for each criterion, distribution in time, and the accumulated percentage of normal seedlings adjusted to time-to-event nonlinear regression. The new interpretation criterion proposed in this study is efficient, and P. taeda seedlings can be considered normal when cotyledon leaves differ by approximately 3 mm between the integument and hypocotyl, reducing the time to conduct the germination test by up to ten days compared to the criterion usually used in the routine analysis of seed laboratories.


Assuntos
Germinação/fisiologia , Pinus taeda/crescimento & desenvolvimento
5.
Am J Bot ; 107(11): 1555-1566, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33205396

RESUMO

PREMISE: Climate change is predicted to affect natural and plantation forests. The responses of conifers to overcome changing environments will depend on their adaptation to local conditions; however, intraspecific adaptive genetic variation is unknown for most gymnosperms. Studying genetic diversity associated with phenotypic variability along environmental gradients will enhance our understanding of adaptation and may reveal genetic pools important for conservation and management. METHODS: We used target enrichment and genome skimming to obtain single nucleotide polymorphisms (SNPs) from 61 individuals of Pinus patula, a pine tree native to Mexico widely used in plantation forestry. We investigated the adaptive genetic variation of two varieties with morphological and distributional differences potentially related to genetic and adaptive divergence. RESULTS: Population structure and haplotype network analyses revealed that genetic diversity between P. patula var. patula and P. patula var. longipedunculata was structured, even within populations of P. patula var. longipedunculata. We observed high genetic diversity, low inbreeding rate, and rapid linkage disequilibrium (LD) decay in the varieties. Based on outlier tests, loci showing signatures of natural selection were detected in geographically distant P. patula var. longipedunculata populations. For both varieties, we found significant correlations between climate-related environmental variation and SNP diversity at loci involved in abiotic stress, cell transport, defense, and cell wall biogenesis, pointing to local adaptation. CONCLUSIONS: Overall, significant intraspecific adaptive genetic variation in P. patula was detected, highlighting the presence of different genetic pools and signs of local adaptation that should be considered in forestry and conservation.


Assuntos
Pinus , Aclimatação , Adaptação Fisiológica/genética , Variação Genética , México , Pinus/genética , Polimorfismo de Nucleotídeo Único , Seleção Genética
6.
New Phytol ; 222(2): 714-725, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30586169

RESUMO

Belowground biota can deeply influence plant invasion. The presence of appropriate soil mutualists can act as a driver to enable plants to colonize new ranges. We reviewed the species of ectomycorrhizal fungi (EMF) that facilitate pine establishment in both native and non-native ranges, and that are associated with their invasion into nonforest settings. We found that one particular group of EMF, suilloid fungi, uniquely drive pine invasion in the absence of other EMF. Although the association with other EMF is variable, suilloid EMF are always associated with invasive pines, particularly at early invasion, when invasive trees are most vulnerable. We identified five main ecological traits of suilloid fungi that may explain their key role at pine invasions: their long-distance dispersal capacity, the establishment of positive biotic interactions with mammals, their capacity to generate a resistant spore bank, their rapid colonization of roots and their long-distance exploration type. These results suggest that the identity of mycorrhizal fungi and their ecological interactions, rather than simply the presence of compatible fungi, are key to the understanding of plant invasion processes and their success or failure. Particularly for pines, their specific association with suilloid fungi determines their invasion success in previously uninvaded ecosystems.


Assuntos
Fungos/fisiologia , Espécies Introduzidas , Pinus/microbiologia , Animais , Mamíferos/fisiologia , Micorrizas/fisiologia , Esporos Fúngicos/fisiologia
7.
Artigo em Inglês | VETINDEX | ID: vti-744253

RESUMO

El objetivo de este estudio es informar un caso de envenenamiento iatrogénico por un producto comercial basado en la trementina en un potro de 3 días y el tratamiento exitoso de esta afección. Se presentó un potro de 3 días de edad que mostraba colapso cardiorrespiratorio agudo, shock anafiláctico, dificultad respiratoria grave, disnea y edema pulmonar. La historia incluía la administración previa de un producto veterinario comercial (UNITIPAN). En el examen clínico: temperatura: (39.9 C), pulso: 135 lpm, respiración 51 lpm, membranas mucosas, congestión húmeda, tiempo de llenado capilar: tres segundos o menos. El potro fue tratado con hidratación de emergencia, duphalito, antiinflamatorio esteroideo, sulfato de atropina y antibiótico. Después de 6 horas de tratamiento, el potro se estabilizó y los signos vitales se normalizaron 8 después. En conclusión, informamos sobre un caso de intoxicación iatrogénica por un producto comercial a base de trementina en un potro de 3 días con un rápido desarrollo de signos de toxicidad aguda y una respuesta muy favorable al tratamiento sintomático.


The aim of this study is to report a case of iatrogenic poisoning by a turpentine-based commercial product in a 3-day-old foal and the successful treatment of this condition. A 3-day-old male foal presented with acute cardio-respiratory collapse, anaphylactic shock, severe respiratory distress, dyspnea and pulmonary edema. The animals history included previous administration of a commercial veterinary product (UNITIPAN). Clinical examination revealed: temperature: (39.9 C), pulse: 135 bpm, respiration: 51 bpm, mucous membranes: moist and congested, capillary refill time: 3 sec or less. The foal was treated with emergency hydration, duphalyte, steroidal anti-inflammatory, atropine sulphate and antibiotic. After 6 h of treatment, the foal was stabilized and vital signs were normalized 8 h after treatment start.


O objetivo deste estudo é relatar um caso de intoxicação iatrogênica por um produto comercial a base de terebentina em um potro de três días de idade e o sucesso do tratamento dessa condição. Um potro de três dias de idade foi apresentou um colapso cardiorrespiratório agudo, choque anafilático, desconforto respiratório grave, dispnéia e edema pulmonar. A história incluiu a administração prévia de um produto veterinário comercial (UNITIPAN). Ao exame clínico: temperatura: (39,9 C), pulso: 135 bpm, respiração 51 bpm, membranas mucosas, congestionamento úmido, tempo de enchimento capilar: três segundos ou menos. O potro foi tratado com hidratação de emergência, duphalyte, anti-inflamatório esteroidal, sulfato de atropina e antibiótico. Após seis horas de tratamento, o potro foi estabilizado e os sinais vitais foram normalizados depois de oito horas do inicio do tratamento. O presente trabalho relata um caso de intoxicação iatrogênica por um produto à base de terebintina comercial em um potro de três dias de idade com rápido desenvolvimento de sinais de toxicidade aguda e uma resposta muito favorável ao tratamento sintomático.

8.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 56(4): e153366, Dezembro 03, 2019.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1048103

RESUMO

The aim of this study is to report a case of iatrogenic poisoning by a turpentine-based commercial product in a 3-day-old foal and the successful treatment of this condition. A 3-day-old male foal presented with acute cardio-respiratory collapse, anaphylactic shock, severe respiratory distress, dyspnea and pulmonary edema. The animal's history included previous administration of a commercial veterinary product (UNITIPAN). Clinical examination revealed: temperature: (39.9 °C), pulse: 135 bpm, respiration: 51 bpm, mucous membranes: moist and congested, capillary refill time: 3 sec or less. The foal was treated with emergency hydration, duphalyte, steroidal anti-inflammatory, atropine sulphate and antibiotic. After 6 h of treatment, the foal was stabilized and vital signs were normalized 8 h after treatment start.(AU)


O objetivo deste estudo é relatar um caso de intoxicação iatrogênica por um produto comercial a base de terebentina em um potro de três días de idade e o sucesso do tratamento dessa condição. Um potro de três dias de idade foi apresentou um colapso cardiorrespiratório agudo, choque anafilático, desconforto respiratório grave, dispnéia e edema pulmonar. A história incluiu a administração prévia de um produto veterinário comercial (UNITIPAN). Ao exame clínico: temperatura: (39,9 °C), pulso: 135 bpm, respiração 51 bpm, membranas mucosas, congestionamento úmido, tempo de enchimento capilar: três segundos ou menos. O potro foi tratado com hidratação de emergência, duphalyte, anti-inflamatório esteroidal, sulfato de atropina e antibiótico. Após seis horas de tratamento, o potro foi estabilizado e os sinais vitais foram normalizados depois de oito horas do inicio do tratamento. O presente trabalho relata um caso de intoxicação iatrogênica por um produto à base de terebintina comercial em um potro de três dias de idade com rápido desenvolvimento de sinais de toxicidade aguda e uma resposta muito favorável ao tratamento sintomático.(AU)


Assuntos
Animais , Pinaceae/toxicidade , Cavalos/anormalidades , Doença Iatrogênica/veterinária , Sinais e Sintomas
9.
Braz. j. vet. res. anim. sci ; 56(4): e153366, Dezembro 03, 2019.
Artigo em Inglês | VETINDEX | ID: vti-25057

RESUMO

The aim of this study is to report a case of iatrogenic poisoning by a turpentine-based commercial product in a 3-day-old foal and the successful treatment of this condition. A 3-day-old male foal presented with acute cardio-respiratory collapse, anaphylactic shock, severe respiratory distress, dyspnea and pulmonary edema. The animal's history included previous administration of a commercial veterinary product (UNITIPAN). Clinical examination revealed: temperature: (39.9 °C), pulse: 135 bpm, respiration: 51 bpm, mucous membranes: moist and congested, capillary refill time: 3 sec or less. The foal was treated with emergency hydration, duphalyte, steroidal anti-inflammatory, atropine sulphate and antibiotic. After 6 h of treatment, the foal was stabilized and vital signs were normalized 8 h after treatment start.(AU)


O objetivo deste estudo é relatar um caso de intoxicação iatrogênica por um produto comercial a base de terebentina em um potro de três días de idade e o sucesso do tratamento dessa condição. Um potro de três dias de idade foi apresentou um colapso cardiorrespiratório agudo, choque anafilático, desconforto respiratório grave, dispnéia e edema pulmonar. A história incluiu a administração prévia de um produto veterinário comercial (UNITIPAN). Ao exame clínico: temperatura: (39,9 °C), pulso: 135 bpm, respiração 51 bpm, membranas mucosas, congestionamento úmido, tempo de enchimento capilar: três segundos ou menos. O potro foi tratado com hidratação de emergência, duphalyte, anti-inflamatório esteroidal, sulfato de atropina e antibiótico. Após seis horas de tratamento, o potro foi estabilizado e os sinais vitais foram normalizados depois de oito horas do inicio do tratamento. O presente trabalho relata um caso de intoxicação iatrogênica por um produto à base de terebintina comercial em um potro de três dias de idade com rápido desenvolvimento de sinais de toxicidade aguda e uma resposta muito favorável ao tratamento sintomático.(AU)


Assuntos
Animais , Pinaceae/toxicidade , Cavalos/anormalidades , Doença Iatrogênica/veterinária , Sinais e Sintomas
10.
Am J Bot ; 105(4): 711-725, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29683492

RESUMO

PREMISE OF THE STUDY: Both incomplete lineage sorting and reticulation have been proposed as causes of phylogenetic incongruence. Disentangling these factors may be most difficult in long-lived, wind-pollinated plants with large population sizes and weak reproductive barriers. METHODS: We used solution hybridization for targeted enrichment and massive parallel sequencing to characterize low-copy-number nuclear genes and high-copy-number plastomes (Hyb-Seq) in 74 individuals of Pinus subsection Australes, a group of ~30 New World pine species of exceptional ecological and economic importance. We inferred relationships using methods that account for both incomplete lineage sorting and reticulation. KEY RESULTS: Concatenation- and coalescent-based trees inferred from nuclear genes mainly agreed with one another, but they contradicted the plastid DNA tree in recovering the Attenuatae (the California closed-cone pines) and Oocarpae (the egg-cone pines of Mexico and Central America) as monophyletic and the Australes sensu stricto (the southern yellow pines) as paraphyletic to the Oocarpae. The plastid tree featured some relationships that were discordant with morphological and geographic evidence and species limits. Incorporating gene flow into the coalescent analyses better fit the data, but evidence supporting the hypothesis that hybridization explains the non-monophyly of the Attenuatae in the plastid tree was equivocal. CONCLUSIONS: Our analyses document cytonuclear discordance in Pinus subsection Australes. We attribute this discordance to ancient and recent introgression and present a phylogenetic hypothesis in which mostly hierarchical relationships are overlain by gene flow.


Assuntos
Pinus/genética , Fluxo Gênico , Genes de Plantas/genética , Marcadores Genéticos/genética , Hibridização Genética , Modelos Genéticos , Filogenia , Pinus/classificação , Alinhamento de Sequência
11.
Neotrop Entomol ; 47(3): 429-432, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28840501

RESUMO

We verified infestation of Oligonychus milleri (McGregor) on plantations of Pinus caribaea (Pinaceae) and of Oligonychus ununguis (Jacobi) on plantations of Eucalyptus urophylla x Eucalyptus grandis (Myrtaceae) in State of Rondônia, Northern region of Brazil. This represents the first record of O. milleri in Brazil. Oligonychus ununguis was recorded previously, on cypress. The damage caused by these two spider mites in the plantations is described herein.


Assuntos
Eucalyptus , Pinus , Tetranychidae , Animais , Brasil
12.
New Phytol ; 208(2): 497-506, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25963605

RESUMO

Coinvasive ectomycorrhizal (ECM) fungi allow Pinaceae species to invade regions otherwise lacking compatible symbionts, but ECM fungal communities permitting Pinaceae invasions are poorly understood. In the context of Pinaceae invasions on Isla Victoria, Nahuel Huapi National Park, Argentina, we asked: what ECM fungi are coinvading with Pinaceae hosts on Isla Victoria; are some ECM fungal species or genera more prone to invade than others; and are all ECM fungal species that associate with Northern Hemisphere hosts also nonnative, or are some native fungi compatible with nonnative plants? We sampled ECMs from 226 Pinaceae host plant individuals, both planted individuals and recruits, growing inside and invading from plantations. We used molecular techniques to examine ECM fungal communities associating with these trees. A distinctive subset of the ECM fungal community predominated far from plantations, indicating differences between highly invasive and less invasive ECM fungi. Some fungal invaders reported here have been detected in other locations around the world, suggesting strong invasion potential. Fungi that were frequently detected far from plantations are often found in early-successional sites in the native range, while fungi identified as late-successional species in the native range are rarely found far from plantations, suggesting a means for predicting potential fungal coinvaders.


Assuntos
Interações Hospedeiro-Patógeno , Micorrizas/fisiologia , Pinaceae/microbiologia , Argentina , Dados de Sequência Molecular , Especificidade da Espécie
13.
Anaerobe ; 30: 146-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25270831

RESUMO

Endodontic infections have a polymicrobial nature, but anaerobic bacteria prevail among the infectious microbes. Considering that it is easy to eliminate planktonic bacteria, biofilm-forming bacteria still challenge clinicians during the fight against endodontic diseases. The chemical constituents of the oleoresin of Pinus elliottii, a plant belonging to the family Pinaceae, stand out in the search for biologically active compounds based on natural products with potential application in the treatment of endodontic infections. Indeed, plant oleoresins are an abundant natural source of diterpenes that display significant and well-defined biological activities as well as potential antimicrobial action. In this context, this study aimed to (1) evaluate the in vitro antibacterial activity of the oleoresin, fractions, and subfractions of P. elliottii as well as the action of dehydroabietic acid against 11 anaerobic bacteria that cause endodontic infection in both their planktonic and biofilm forms and (2) assess the in vitro antibiofilm activity of dehydroabietic acid against the same group of bacteria. The broth microdilution technique helped to determine the minimum inhibitory concentration (MIC) of the oleoresin and fractions. This same technique aided determination of the MIC values of nine subfractions of Fraction 1, the most active fraction. The MIC, minimum bactericidal concentration, and antibiofilm activity of dehydroabietic acid against the tested anaerobic bacteria were also examined. The oleoresin and fractions, especially fraction PE1, afforded promising MIC values, which ranged from 0.4 to 50 µg/mL. Concerning the nine evaluated subfractions, PE1.3 and PE1.4 furnished the most noteworthy MIC values, between 6.2 and 100 µg/mL. Dehydroabietic acid displayed antibacterial activity, with MIC values lying from 6.2 to 50 µg/mL, as well as bactericidal effect for all the investigated bacteria, except for Prevotella nigrescens. Assessment of the antibiofilm activity revealed significant results--MICB50 lay between 7.8 and 62.5 µg/mL, and dehydroabietic acid prevented all the evaluated bacteria from forming a biofilm. Hence, the chemical constituents of P. elliottii are promising biomolecules to develop novel therapeutic strategies to fight against endodontic infections.


Assuntos
Abietanos/farmacologia , Antibacterianos/farmacologia , Bactérias Anaeróbias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Pinus/química , Extratos Vegetais/farmacologia , Pulpite/microbiologia , Abietanos/isolamento & purificação , Antibacterianos/isolamento & purificação , Bactérias Anaeróbias/isolamento & purificação , Bactérias Anaeróbias/fisiologia , Biofilmes/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA