Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
Mycorrhiza ; 34(3): 159-171, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38625427

RESUMO

Climate change and global warming have contributed to increase terrestrial drought, causing negative impacts on agricultural production. Drought stress may be addressed using novel agronomic practices and beneficial soil microorganisms, such as arbuscular mycorrhizal fungi (AMF), able to enhance plant use efficiency of soil resources and water and increase plant antioxidant defence systems. Specific traits functional to plant resilience improvement in dry conditions could have developed in AMF growing in association with xerophytic plants in maritime sand dunes, a drought-stressed and low-fertility environment. The most studied of such plants are European beachgrass (Ammophila arenaria Link), native to Europe and the Mediterranean basin, and American beachgrass (Ammophila breviligulata Fern.), found in North America. Given the critical role of AMF for the survival of these beachgrasses, knowledge of the composition of AMF communities colonizing their roots and rhizospheres and their distribution worldwide is fundamental for the location and isolation of native AMF as potential candidates to be tested for promoting crop growth and resilience under climate change. This review provides quantitative and qualitative data on the occurrence of AMF communities of A. arenaria and A. breviligulata growing in European, Mediterranean basin and North American maritime sand dunes, as detected by morphological studies, trap culture isolation and molecular methods, and reports on their symbiotic performance. Moreover, the review indicates the dominant AMF species associated with the two Ammophila species and the common species to be further studied to assess possible specific traits increasing their host plants resilience toward drought stress under climate change.


Assuntos
Mudança Climática , Micorrizas , Simbiose , Micorrizas/fisiologia , Europa (Continente) , América do Norte , Microbiologia do Solo , Secas , Areia/microbiologia
2.
J Sci Food Agric ; 102(6): 2352-2358, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34636032

RESUMO

BACKGROUND: Tomato is widely consumed throughout the world for its flavor and nutritional value. This functional food largely depends on the implementation of new strategies to maintain the nutraceutical value, e.g. lycopene concentration, and overcome the challenges of sustainable production and food security. The use of arbuscular mycorrhizal fungi (AMF)-based biostimulants represents one of the most promising tools for sustainable management of agricultural soils, being fundamental for organic food production, reducing fertilizers and pesticides use, and decreasing environmental damage. This study aimed at elucidating whether native arbuscular mycorrhizal fungi (AMF) could positively affect tomato yield and lycopene concentration. RESULTS: Native AMF inoculum consisted of two inoculum types: the single species Claroideoglomus claroideum, and a mix of Scutellospora calospora, Acaulospora laevis, Claroideoglomus claroideum, and Claroideoglomus etunicatum. At the end of the study up to 78% of the root system was colonized by single inoculum. Tomato diameters in single and mix mycorrhizal plants showed increases of 80% and 35% respectively. Fresh weights were 84% and 38% higher with single and mix inocula compared with the controls, respectively. The lycopene concentration in tomato fruits of plants with single and mix inoculum was higher than controls. The lycopene concentration was 124.5% and 113.9% greater in single and mix than non-inoculated plants. CONCLUSION: Tomato diameters, fresh weight and lycopene concentration was significantly higher in plants colonized by AMF compared with uninoculated plants. Results suggest that the role of single species Claroideoglomus claroideum could generate better plant performance due to its high production of extraradical mycelium. © 2021 Society of Chemical Industry.


Assuntos
Micorrizas , Solanum lycopersicum , Fungos , Licopeno , Solanum lycopersicum/microbiologia , Plantas , Solo
3.
Mycorrhiza ; 31(5): 527-544, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34286366

RESUMO

Arbuscular mycorrhizal fungi (AMF) represent an important group of root symbionts, given the key role they play in the enhancement of plant nutrition, health, and product quality. The services provided by AMF often are facilitated by large and diverse beneficial bacterial communities, closely associated with spores, sporocarps, and extraradical mycelium, showing different functional activities, such as N2 fixation, nutrient mobilization, and plant hormone, antibiotic, and siderophore production and also mycorrhizal establishment promotion, leading to the enhancement of host plant performance. The potential functional complementarity of AMF and associated microbiota poses a key question as to whether members of AMF-associated bacterial communities can colonize the root system after establishment of mycorrhizas, thereby becoming endophytic. Root endophytic bacterial communities are currently studied for the benefits provided to host plants in the form of growth promotion, stress reduction, inhibition of plant pathogens, and plant hormone release. Their quantitative and qualitative composition is influenced by many factors, such as geographical location, soil type, host genotype, and cultivation practices. Recent data suggest that an additional factor affecting bacterial endophyte recruitment could be AMF and their associated bacteria, even though the mechanisms allowing members of AMF-associated bacterial communities to actually establish in the root system, becoming endophytic, remain to be determined. Given the diverse plant growth-promoting properties shown by AMF-associated bacteria, further studies are needed to understand whether AMF may represent suitable tools to introduce beneficial root endophytes in sustainable and organic agriculture where the functioning of such multipartite association may be crucial for crop production.


Assuntos
Micorrizas , Bactérias , Fungos , Raízes de Plantas , Solo , Microbiologia do Solo
4.
Mycorrhiza ; 30(2-3): 373-387, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32227272

RESUMO

Arbuscular mycorrhizal fungi (AMF) play a fundamental role in plant growth and nutrition in natural and agricultural ecosystems. Despite the importance of such symbionts, the different developmental changes occurring during the AMF life cycle have not been fully elucidated at the molecular level. Here, the RNA-seq approach was used to investigate Rhizoglomus irregulare specific and common transcripts at two different time points of mycorrhizal establishment in Helianthus annuus in vivo. Four days after inoculation, transcripts related to cellular remodeling (actin and tubulin), cellular signaling (calmodulin, serine/threonine protein kinase, 14-3-3 protein, and calcium transporting ATPase), lipid metabolism (fatty acid desaturation, steroid hormone, and glycerophospholipid biosynthesis), and biosynthetic processes were detected. In addition to such transcripts, 16 days after inoculation, expressed genes linked to binding and catalytic activities; ion (K+, Ca2+, Fe2+, Zn2+, Mn2+, Pi, ammonia), sugar, and lipid transport; and those involved in vacuolar polyphosphate accumulation were found. Knowledge of transcriptomic changes required for symbiosis establishment and performance is of great importance to understand the functional role of AMF symbionts in food crop nutrition and health, and in plant diversity in natural ecosystems.


Assuntos
Glomeromycota , Helianthus , Micorrizas , Ecossistema , Raízes de Plantas , RNA-Seq , Simbiose
5.
Mycorrhiza ; 26(7): 699-707, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27179537

RESUMO

In recent years, arbuscular mycorrhizal fungi (AMF) have been reported to enhance plant biosynthesis of secondary metabolites with health-promoting activities, such as polyphenols, carotenoids, vitamins, anthocyanins, flavonoids and lycopene. In addition, plant growth-promoting (PGP) bacteria were shown to modulate the concentration of nutraceutical compounds in different plant species. This study investigated for the first time whether genes encoding key enzymes of the biochemical pathways leading to the production of rosmarinic acid (RA), a bioactive compound showing antioxidant, antibacterial, antiviral and anti-inflammatory properties, were differentially expressed in Ocimum basilicum (sweet basil) inoculated with AMF or selected PGP bacteria, by using quantitative real-time reverse transcription PCR. O. basilicum plants were inoculated with either the AMF species Rhizophagus intraradices or a combination of two PGP bacteria isolated from its sporosphere, Sinorhizobium meliloti TSA41 and Streptomyces sp. W43N. Present data show that the selected PGP bacteria were able to trigger the overexpression of tyrosine amino-transferase (TAT), hydroxyphenylpyruvate reductase (HPPR) and p-coumaroyl shikimate 3'-hydroxylase isoform 1 (CS3'H iso1) genes, 5.7-fold, 2-fold and 2.4-fold, respectively, in O. basilicum leaves. By contrast, inoculation with R. intraradices triggered TAT upregulation and HPPR and CS3'H iso1 downregulation. Our data suggest that inoculation with the two selected strains of PGP bacteria utilised here could represent a suitable biotechnological tool to be implemented for the production of O. basilicum plants with increased levels of key enzymes for the biosynthesis of RA, a compound showing important functional properties as related to human health.


Assuntos
Bactérias/metabolismo , Cinamatos/metabolismo , Depsídeos/metabolismo , Glomeromycota/fisiologia , Ocimum basilicum/metabolismo , Ocimum basilicum/microbiologia , Cinamatos/química , Depsídeos/química , Regulação da Expressão Gênica de Plantas , Estrutura Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ácido Rosmarínico
6.
Neurol Sci ; 36(10): 1897-902, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26081007

RESUMO

The aim of our study was to translate and to do a linguistic validation of the Composite Autonomic Symptom Score COMPASS 31. COMPASS 31 is a self-assessment instrument including 31 items assessing six domains of autonomic functions: orthostatic intolerance, vasomotor, secretomotor, gastrointestinal, bladder, and pupillomotor functions. This questionnaire has been created by the Autonomic group of the Mayo Clinic from two previous versions: the Autonomic Symptom Profile (ASP) composed of 169 items and the following COMPASS with 72 items selected from the ASP. We translated the questionnaire by means of a standardized forward and back-translation procedure. Thirty-six subjects, 25 patients with autonomic failure of different aethiologies and 11 healthy controls filled in the COMPASS 31 twice, 4 ± 1 weeks apart, once in Italian and once in English in a randomized order. The test-retest showed a significant correlation between the Italian and the English versions as total score. The evaluation of single domains by means of Pearson correlation when applicable or by means of Spearman test showed a significant correlation between the English and the Italian COMPASS 31 version for all clinical domains except the vasomotor one for the lack of scoring. The comparison between the patients with autonomic failure and healthy control groups showed significantly higher total scores in patients with respect to controls confirming the high sensitivity of COMPASS 31 in revealing autonomic symptoms.


Assuntos
Doenças do Sistema Nervoso Autônomo/diagnóstico , Sistema Nervoso Autônomo , Autoavaliação Diagnóstica , Linguística , Traduções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Neurol Res ; 45(5): 435-439, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36683154

RESUMO

OBJECTIVES: Peripheral nerve glomus tumors are extremely rare and occur with typical symptoms of peripheral neuropathic pain. Clinicians hardly consider this entity when faced with the swelling of a peripheral nerve and the diagnosis is reached only with histological examination. Nerves of limbs are usually affected and the solid glomus tumor is the most frequent histological variant. CASE DESCRIPTION: A 55-year-old man presented with a glomus tumor of the anterior supraclavicular nerve of the left cervical plexus, misdiagnosed clinically and radiologically as neuroma. Despite the preoperative suspicion and the intraoperative appearance, the histological examination revealed a glomus tumor with a prevalent muscular component, a glomangiomyoma. Once the tumor was removed, pain regressed completely. CONCLUSIONS: Because of its rarity, pre-operative diagnosis of glomus tumors is still a challenge, especially when arising from peripheral nerves. In the presence of chronic localized neuroma-type pain and sensitivity, glomus tumors should be considered in the pool of differential diagnosis, even if the imaging is not conclusive.


Assuntos
Tumor Glômico , Neuroma , Neoplasias do Sistema Nervoso Periférico , Masculino , Humanos , Pessoa de Meia-Idade , Tumor Glômico/complicações , Tumor Glômico/diagnóstico por imagem , Tumor Glômico/cirurgia , Neoplasias do Sistema Nervoso Periférico/complicações , Neoplasias do Sistema Nervoso Periférico/diagnóstico por imagem , Neoplasias do Sistema Nervoso Periférico/cirurgia , Neuroma/diagnóstico por imagem , Neuroma/cirurgia , Dor , Plexo Cervical/diagnóstico por imagem , Plexo Cervical/patologia
8.
Neurol Res ; 45(6): 530-537, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36617792

RESUMO

INTRODUCTION: Synovial sarcomas occurring as primary nerve tumors (SSPN) are rare and only 69 cases of SSPNs are reported in literature. Despite the little data available, SSPNs differ from other SSs in some distinctive aspects such as epidemiology, location, and early onset of symptoms. SSPN are consequently underdiagnosed and easily mistaken for benign or malignant peripheral nerve sheath tumors (PNST). Therefore, cytogenetic or molecular testing becomes essential in order to make a correct diagnosis. This article deals with an extremely rare case of monophasic SSPN of the posterior cords of the right brachial plexus. To our knowledge, this is only the tenth case of intraneural synovial sarcoma involving the brachial plexus. CASE PRESENTATION: We report the case of a 64-year-old man, who came to our attention due to a slow-growing painful right axillary neoformation, approximately 25 mm in size. The patient did not show any neurological impairments. Ultrasonography and constrast MRI showed a heterogeneous mass arising from the posterior cord of the right brachial plexus, resembling a schwannoma. The patient underwent total resection of tumor and capsule. Histologically, a diagnosis of monophasic synovial sarcoma was made based on histologic features and the immunohistochemical profile. CONCLUSIONS: We report a rare primary synovial sarcoma of the brachial plexus. Given its rarity, the diagnosis may be challenging and requires a core biopsy or the surgical specimen to permit immune-molecular analysis. Margin-free surgery is the mainstay of curative treatment, while chemo- or radiotherapy may have a role in advanced or margin-positive neoplasms.


Assuntos
Plexo Braquial , Neurilemoma , Neoplasias do Sistema Nervoso Periférico , Sarcoma Sinovial , Masculino , Humanos , Pessoa de Meia-Idade , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/cirurgia , Sarcoma Sinovial/patologia , Neoplasias do Sistema Nervoso Periférico/diagnóstico , Neoplasias do Sistema Nervoso Periférico/cirurgia , Neoplasias do Sistema Nervoso Periférico/patologia , Neurilemoma/diagnóstico , Neurilemoma/cirurgia , Neurilemoma/patologia , Diagnóstico Diferencial , Plexo Braquial/cirurgia
9.
Neurol Res ; 45(7): 667-675, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36789552

RESUMO

OBJECTIVE: Anatomical abnormalities in the thoracic outlet syndrome are very frequent, but radiological images are not always reliable. Therefore, the different features and abilities of CT angiogram and brachial plexus MRI to detect anatomical abnormalities have been investigated. METHODS: All radiological and surgical records of patients operated for thoracic outlet syndrome between January 2011 and December 2018 were retrospectively analyzed. Considering the CT angiogram and/or brachial plexus MRI reports of the preoperative period, the performance of these investigations was evaluated by calculating the precision (P), sensitivity (Recall) and Hamming loss (L). RESULTS: From a total of 107 patients screened, 84 were eligible for study inclusion. Out of these, 46 had surgical abnormalities (group 1), while 38 did not (group 2). Among them, 30 patients have performed CT angiogram (subgroup A), 32 brachial plexus MRI (subgroup B) and 22 both (subgroup C). The best result is obtained when both diagnostic examinations are performed (subgroup C: P = 0.62; recall = 0.52; L = 0.038). CONCLUSIONS: Prescribing both investigations in selected patients increases the probability of finding anatomic anomalies and facilitates preoperative planning. However, as the radiological images are not completely exhaustive, the surgeon should always actively search and remove any potential source of compression on the nervous vascular bundle along the thoracic outlet.


Assuntos
Plexo Braquial , Síndrome do Desfiladeiro Torácico , Humanos , Estudos Retrospectivos , Síndrome do Desfiladeiro Torácico/diagnóstico por imagem , Síndrome do Desfiladeiro Torácico/cirurgia , Plexo Braquial/diagnóstico por imagem , Plexo Braquial/cirurgia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
10.
J Neurosurg Sci ; 67(6): 758-766, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35301833

RESUMO

BACKGROUND: Despite being previously considered as congenital lesions, recent studies agree to classify cerebral cavernous malformations (CCM) as acquired forms with clear correlations with other pathological affections of the central nervous system (CNS). In addition, a special subgroup, notably known as de novo CCMs (dnCCM), are associated in a significant number of cases with developmental venous anomalies (DVAs) and, in other cases, with Radiotherapy treatments. METHODS: A mini-series of 4 patients with clinical history characterized by developing dnCCM is reported. In three patients, the dnCCM was associated with the presence of an isolated DVA. In one case, no DVA was detected, but the patient underwent brain radiotherapy. In three cases, the dnCCM was clinically symptomatic, and the patients were submitted to a surgical procedure for lesion removal. In one case, the dnCCM was detected during MRI follow-up. RESULTS: Adding a review of the literature, we describe 47 patients who presented dnCCMs. The most common presentation is a sporadic CCM with a DVA, and the onset presentation was bleeding in 4 out of 47 cases (8.5%). Bleeding of dnCCM was observed in 9 out of 47 cases (19%), and the choice treatment was surgical in 24 out of 47 cases (51%). CONCLUSIONS: We present our series with a review of the recent literature and discuss the "de novo" cavernous malformation pathogenesis. A throughout review of recent literature is reported to clarify the predisposing factors that may lead to dnCCM development in patients carrying specific genetic and molecular features. Considering the high risk of bleeding, strict follow-up and aggressive treatment should be evaluated in dnCCM management.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central , Hemangioma Cavernoso , Deficiência Intelectual , Micrognatismo , Costelas/anormalidades , Humanos , Hemangioma Cavernoso/complicações , Hemangioma Cavernoso/cirurgia , Hemangioma Cavernoso do Sistema Nervoso Central/complicações , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Imageamento por Ressonância Magnética , Deficiência Intelectual/complicações
11.
Front Plant Sci ; 14: 1240310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023909

RESUMO

The sustainable intensification of maize-based systems may reduce greenhouse-gas emissions and the excessive use of non-renewable inputs. Considering the key role that the microbiological fertility has on crop growth and resilience, it is worth of interest studying the role of cropping system on the rhizosphere bacterial communities, that affect soil health and biological soil fertility. In this work we monitored and characterized the diversity and composition of native rhizosphere bacterial communities during the early growth phases of two maize genotypes of different early vigor, using a nitrogen (N)-phosphorus (P) starter fertilization and a biostimulant seed treatment, in a growth chamber experiment, by polymerase chain reaction-denaturing gradient gel electrophoresis of partial 16S rRNA gene and amplicon sequencing. Cluster analyses showed that the biostimulant treatment affected the rhizosphere bacterial microbiota of the ordinary hybrid more than that of the early vigor, both at plant emergence and at the 5-leaf stage. Moreover, the diversity indices calculated from the community profiles, revealed significant effects of NP fertilization on richness and the estimated effective number of species (H2) in both maize genotypes, while the biostimulant had a positive effect on plant growth promoting community of the ordinary hybrid, both at the plant emergence and at the fifth leaf stage. Our data showed that maize genotype was the major factor shaping rhizosphere bacterial community composition suggesting that the root system of the two maize hybrids recruited a different microbiota. Moreover, for the first time, we identified at the species and genus level the predominant native bacteria associated with two maize hybrids differing for vigor. These results pave the way for further studies to be performed on the effects of cropping system and specific crop practices, considering also the application of biostimulants, on beneficial rhizosphere microorganisms.

12.
Environ Sci Pollut Res Int ; 30(19): 56207-56223, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36917375

RESUMO

The increased ultraviolet radiation (UV) due to the altered stratospheric ozone leads to multiple plant physiological and biochemical adaptations, likely affecting their interaction with other organisms, such as pests and pathogens. Arbuscular mycorrhizal fungi (AMF) and UV-B treatment can be used as eco-friendly techniques to protect crops from pests by activating plant mechanisms of resistance. In this study, we investigated plant (Lactuca sativa) response to UV-B exposure and Funneliformis mosseae (IMA1) inoculation as well as the role of a major insect pest, Spodoptera littoralis. Lettuce plants exposed to UV-B were heavier and taller than non-irradiated ones. A considerable enrichment in phenolic, flavonoid, anthocyanin, and carotenoid contents and antioxidant capacity, along with redder and more homogenous leaf color, were also observed in UV-B-treated but not in AMF-inoculated plants. Biometric and biochemical data did not differ between AMF and non-AMF plants. AMF-inoculated plants showed hyphae, arbuscules, vesicles, and spores in their roots. AMF colonization levels were not affected by UV-B irradiation. No changes in S. littoralis-feeding behavior towards treated and untreated plants were observed, suggesting the ability of this generalist herbivore to overcome the plant chemical defenses boosted by UV-B exposure. The results of this multi-factorial study shed light on how polyphagous insect pests can cope with multiple plant physiological and biochemical adaptations following biotic and abiotic preconditioning.


Assuntos
Micorrizas , Animais , Micorrizas/fisiologia , Lactuca , Raios Ultravioleta , Raízes de Plantas/metabolismo , Spodoptera , Folhas de Planta/química
13.
New Phytol ; 194(3): 810-822, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22380845

RESUMO

• Inoculation of crop plants by non-native strains of arbuscular mycorrhizal (AM) fungi as bio-enhancers is promoted without clear evidence for symbiotic effectiveness and fungal persistence. To address such gaps, the forage legume Medicago sativa was inoculated in an agronomic field trial with two isolates of Funneliformis mosseae differing in their nuclear rDNA sequences from native strains. • The inoculants were traced by PCR with a novel combination of the universal fungal NS31 and Glomeromycota-specific LSUGlom1 primers which target the nuclear rDNA cistron. The amplicons were classified by restriction fragment length polymorphism and sequencing. • The two applied fungal inoculants were successfully traced and discriminated from native strains in roots sampled from the field up to 2 yr post inoculation. Moreover, field inoculation with inocula of non-native isolates of F. mosseae appeared to have stimulated root colonization and yield of M. sativa. • Proof of inoculation success and sustained positive effects on biomass production and quality of M. sativa crop plants hold promise for the role that AM fungal inoculants could play in agriculture.


Assuntos
Glomeromycota/fisiologia , Medicago sativa/microbiologia , Micorrizas/fisiologia , Inoculantes Agrícolas , Agricultura , Sequência de Bases , Biomassa , Produtos Agrícolas , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Marcadores Genéticos/genética , Glomeromycota/genética , Glomeromycota/crescimento & desenvolvimento , Medicago sativa/genética , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/fisiologia , Dados de Sequência Molecular , Micorrizas/genética , Micorrizas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , Brotos de Planta/fisiologia , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Especificidade da Espécie , Simbiose
14.
Mycorrhiza ; 22(2): 81-97, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22075570

RESUMO

Soil fungi play a crucial role in producing fundamental ecosystem services such as soil fertility, formation and maintenance, nutrient cycling and plant community dynamics. However, they have received little attention in the field of conservation biology. Arbuscular mycorrhizal fungi (AMF) are beneficial soil symbionts fulfilling a key function in the complex networks of belowground/aboveground biotic interactions as they live in association with the roots of most (80%) land plant families and influence not only soil fertility but also plant nutrition, diversity and productivity. The diversity of AMF communities can decline due to habitat loss and anthropogenic disturbance, especially in agro-ecosystems, and many valuable ecotypes could become extinct before they are even discovered. Consequently, long-term strategies are urgently needed to ensure their conservation in habitats where they naturally occur and have evolved. Protected areas, where living organisms are under the care of national and international authorities, represent an appropriate place for the in situ conservation of AMF, providing them with adapted situations together with established complex networks of interactions with different components within each specific ecosystem. Here, we review data available about the main present-day threats to AMF and the current state of knowledge about their occurrence in protected sites worldwide, providing a checklist of national parks and nature reserves where they have been reported. The aim was to offer a strategic perspective to increase awareness of the importance of conserving these beneficial plant symbionts and of preserving their biodiversity in the years to come.


Assuntos
Conservação dos Recursos Naturais , Fungos/fisiologia , Micorrizas/fisiologia , Microbiologia do Solo , Biodiversidade , Fungos/isolamento & purificação , Micorrizas/isolamento & purificação , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Simbiose
15.
Sci Rep ; 12(1): 21279, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482115

RESUMO

Food production is heavily dependent on soil phosphorus (P), a non-renewable mineral resource essential for plant growth and development. Alas, about 80% is unavailable for plant uptake. Arbuscular mycorrhizal fungi may promote soil P efficient use, although the mechanistic aspects are yet to be completely understood. In this study, plant and fungal variables involved in P acquisition were investigated in maize inbred lines, differing for mycorrhizal responsiveness and low-P tolerance, when inoculated with the symbiont Rhizoglomus irregulare (synonym Rhizophagus irregularis). The expression patterns of phosphate transporter (PT) genes in extraradical and intraradical mycelium (ERM/IRM) and in mycorrhizal and control maize roots were assessed, together with plant growth responses and ERM extent and structure. The diverse maize lines differed in plant and fungal accumulation patterns of PT transcripts, ERM phenotypic traits and plant performance. Mycorrhizal plants of the low-P tolerant maize line Mo17 displayed increased expression of roots and ERM PT genes, compared with the low-P susceptible line B73, which revealed larger ERM hyphal densities and interconnectedness. ERM structural traits showed significant correlations with plant/fungal expression levels of PT genes and mycorrhizal host benefit, suggesting that both structural and functional traits are differentially involved in the regulation of P foraging capacity in mycorrhizal networks.


Assuntos
Micorrizas , Zea mays , Proteínas de Transporte de Fosfato/genética , Zea mays/genética , Zea mays/microbiologia
16.
Foods ; 11(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36429202

RESUMO

Lettuce is widely used for its healthy properties, and it is of interest to increase them with minimal environmental impact. The purpose of this work was to evaluate the effect of the arbuscular mycorrhizal fungus (AMF) Funneliformis mosseae in lettuce plants (Lactuca sativa L. cv. Salinas) cultivated in a soilless system with sub-optimal phosphorus (P) compared with non-inoculated controls at two different P concentrations. Results show that lettuce inoculation with the selected AMF can improve the growth and the nutritional quality of lettuce even at sub-optimal P. Leaf content of chlorophylls, carotenoids, and phenols, known as important bioactive compounds for human health, was higher in mycorrhizal lettuce plants compared with non-mycorrhizal plants. The antioxidant capacity in AMF plants showed higher values compared with control plants grown at optimal P nutrition level. Moreover, leaf gas exchanges were higher in inoculated plants than in non-inoculated ones. Nitrogen, P, and magnesium leaf content was significantly higher in mycorrhizal plants compared with non-mycorrhizal plants grown with the same P level. These findings suggest that F. mosseae can stimulate plants growth, improving the nutritional quality of lettuce leaves even when grown with sub-optimal P concentration.

17.
Bioresour Bioprocess ; 9(1): 45, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38647844

RESUMO

In recent years the use of organic matter soil amendments, such as agricultural by-products, has been implemented with the aim of increasing soil fertility, while minimizing the environmental impact of agriculture. Sheep wool residues (SWR) have shown beneficial effects on plant nutrition and soil properties, while only few works assessed their impact on soil microbial communities. The main aim of this work was to investigate the possible valorization of two SWR types (scoured residues, white wool, WW, and carbonized scoured residues, black wool, BW) as organic soil amendments, in pot-grown olive trees, by evaluating their impact on soil bacterial communities and mycorrhizal symbionts. The two SWR types did not negatively impact on the diversity and composition of soil bacterial communities, as revealed by PCR-denaturating gradient gel electrophoresis (PCR-DGGE) of partial 16S rRNA gene, and on the activity of native arbuscular mycorrhizal fungi (AMF), while positively affecting plant growth. Only the highest doses of one SWR type (2% BW) caused a decrease in bacterial diversity and native AMF ability to colonize olive roots. DGGE bands sequencing allowed the identification of the major bacterial taxa. Sequences corresponding to Ohtaekwangia spp., Beta proteobacterium, Blastocatella sp., Ramlibacter monticola and Massilia frigida/rubra, Dongia sp. and Chloroflexi were mainly represented in SWR-amended soils, while those represented by Chryseolinea soli and Acidobacteria were abundant in control soil. Overall, this work showed that SWR may be valorized as organic soil amendments, as soil bacteria and AMF, representing key factors of biological soil fertility, were not negatively affected, while the activity of bacterial genera and species known for their ability to decompose complex compounds was boosted. Further studies will investigate the biodegradation efficiency of the diverse bacterial taxa developing in SWR-amended soils.

18.
Front Microbiol ; 13: 826571, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35317261

RESUMO

The crop Vitis vinifera (L.) is of great economic importance as Chile is one of the main wine-producing countries, reaching a vineyard area of 145,000 ha. This vine crop is usually very sensitive to local condition changes and agronomic practices; therefore, strategies to counteract the expected future decrease in water level for agricultural irrigation, temperature increase, extreme water stress (abiotic stress), as well as increase in pathogenic diseases (biotic stress) related to climate change will be of vital importance for this crop. Studies carried out in recent years have suggested that arbuscular mycorrhizal fungi (AMF) can provide key ecosystem services to host plants, such as water uptake implementation and enhanced absorption of nutrients such as P and N, which are key factors for improving the nutritional status of the vine. AMF use in viticulture will contribute also to sustainable agronomic management and bioprotection against pathogens. Here we will present (1) the current status of grapevines in Chile, (2) the main problems in grapevines related to water stress and associated with climate change, (3) the importance of AMF to face water stress and pathogens, and (4) the application of AMF as a biotechnological and sustainable tool in vineyards.

19.
Insects ; 14(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36661948

RESUMO

Arbuscular mycorrhizal fungi (AMF) and ultraviolet-B radiation (UV-B) play important roles in plant-insect interactions by altering plant physiology and histology. We hypothesized that UV-B-induced oxidative stress was mitigated by AMF symbiosis. In this study, we conducted a multifactorial experiment to explore lettuce plant response to AMF inoculation and UV-B exposure (0.4 W m-2; 16 h d-1; 2 weeks), either together or individually, as well as the interaction with the polyphagous insect pest Myzus persicae (Sulzer). Lettuce plants subjected to UV-B radiation showed an increase in callose and oxidative stress indicators, as well as a decrease in stomatal density. Mycorrhizal colonization cancelled out the effect of UV-B on stomatal density, while the symbiosis was not affected by UV-B treatment. The plant volatile emission was significantly altered by UV-B treatment. Specifically, the non-terpene 1-undecene abundance (+M/+UVB: 48.0 ± 7.78%; -M/+UVB: 56.6 ± 14.90%) was increased, whereas the content of the non-terpene aldehydes decanal (+M/+UVB: 8.50 ± 3.90%; -M/+UVB: 8.0 ± 4.87%) and undecanal (+M/+UVB: 2.1 ± 0.65%; -M/+UVB: 1.20 ± 1.18%) and the sesquiterpene hydrocarbons (+M/+UVB: 18.0 ± 9.62 %; -M/+UVB: 19.2 ± 5.90%) was decreased. Mycorrhization, on the other hand, had no significant effect on the plant volatilome, regardless of UV-B treatment. Aphid population was unaffected by any of the treatments, implying a neutral plant response. Overall, this study provides new insights about the interactions among plants, UV-B, and AMF, outlining their limited impact on a polyphagous insect pest.

20.
World Neurosurg ; 145: 119-126, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949802

RESUMO

BACKGROUND: Isolated spinal artery aneurysms are an extremely rare cause of subarachnoid hemorrhage. A limited number of case reports and case series have been reported in the literature. Treatment options include conservative management, surgical clipping/trapping, and endovascular procedures. Owing to the uncertain natural history of these lesions, there is no consensus about the optimal treatment. CASE DESCRIPTION: A 64-year-old man presented with subarachnoid hemorrhage from a ruptured anterior spinal artery aneurysm at the C1 level. Following initial conservative management, surgical treatment was proposed owing to an increase in lesion size at angiographic follow-up. A partially thrombosed aneurysm was found during surgery, suggesting that spontaneous resolution of the aneurysm was occurring. Despite initial worsening of neurological symptoms, the patient gradually recovered after rehabilitation. CONCLUSIONS: Treatment decisions for spinal aneurysms should be made on a case-by-case basis, the goal being to offer the patient the best option, while avoiding exposure to unnecessary invasive procedures. As spontaneous resolution of a spinal artery aneurysm is unpredictable, our case highlights the importance of performing a perioperative vascular study if surgery is planned.


Assuntos
Aneurisma Roto/cirurgia , Procedimentos Endovasculares/métodos , Procedimentos Neurocirúrgicos/métodos , Doenças da Coluna Vertebral/cirurgia , Aneurisma Roto/reabilitação , Angiografia Digital , Tratamento Conservador , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/reabilitação , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa