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1.
Microbiome ; 12(1): 83, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725008

RESUMO

BACKGROUND: Fungi and bacteria coexist in a wide variety of environments, and their interactions are now recognized as the norm in most agroecosystems. These microbial communities harbor keystone taxa, which facilitate connectivity between fungal and bacterial communities, influencing their composition and functions. The roots of most plants are associated with arbuscular mycorrhizal (AM) fungi, which develop dense networks of hyphae in the soil. The surface of these hyphae (called the hyphosphere) is the region where multiple interactions with microbial communities can occur, e.g., exchanging or responding to each other's metabolites. However, the presence and importance of keystone taxa in the AM fungal hyphosphere remain largely unknown. RESULTS: Here, we used in vitro and pot cultivation systems of AM fungi to investigate whether certain keystone bacteria were able to shape the microbial communities growing in the hyphosphere and potentially improved the fitness of the AM fungal host. Based on various AM fungi, soil leachates, and synthetic microbial communities, we found that under organic phosphorus (P) conditions, AM fungi could selectively recruit bacteria that enhanced their P nutrition and competed with less P-mobilizing bacteria. Specifically, we observed a privileged interaction between the isolate Streptomyces sp. D1 and AM fungi of the genus Rhizophagus, where (1) the carbon compounds exuded by the fungus were acquired by the bacterium which could mineralize organic P and (2) the in vitro culturable bacterial community residing on the surface of hyphae was in part regulated by Streptomyces sp. D1, primarily by inhibiting the bacteria with weak P-mineralizing ability, thereby enhancing AM fungi to acquire P. CONCLUSIONS: This work highlights the multi-functionality of the keystone bacteria Streptomyces sp. D1 in fungal-bacteria and bacterial-bacterial interactions at the hyphal surface of AM fungi. Video Abstract.


Assuntos
Hifas , Microbiota , Micorrizas , Raízes de Plantas , Microbiologia do Solo , Streptomyces , Micorrizas/fisiologia , Micorrizas/classificação , Streptomyces/classificação , Streptomyces/isolamento & purificação , Streptomyces/genética , Streptomyces/fisiologia , Hifas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Fósforo/metabolismo , Interações Microbianas/fisiologia , Solo/química , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo
2.
New Phytol ; 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38044555

RESUMO

Arbuscular mycorrhizal (AM) fungi-associated hyphosphere microbiomes can be considered as the second genome of the mycorrhizal phosphorus uptake pathway. Their composition can be thought of as a stably recurring component of a holobiont, defined by the hyphosphere core microbiome, which is thought to benefit AM fungal fitness. Here, we review evidence indicating the existence of the hyphosphere core microbiome, highlight its functions linked to those functions lacking in AM fungi, and further explore the mechanisms by which different core members ensure their stable coexistence. We conclude that deciphering and utilizing the hyphosphere core microbiome provides an entry point for understanding the complex interactions among plants, AM fungi, and bacteria.

3.
Sci China Life Sci ; 66(6): 1426-1439, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36811801

RESUMO

Ecology seeks to explain species coexistence, but experimental tests of mechanisms for coexistence are difficult to conduct. We synthesized an arbuscular mycorrhizal (AM) fungal community with three fungal species that differed in their capacity of foraging for orthophosphate (P) due to differences in soil exploration. We tested whether AM fungal species-specific hyphosphere bacterial assemblages recruited by hyphal exudates enabled differentiation among the fungi in the capacity of mobilizing soil organic P (Po). We found that the less efficient space explorer, Gigaspora margarita, obtained less 13C from the plant, whereas it had higher efficiencies in Po mobilization and alkaline phosphatase (AlPase) production per unit C than the two efficient space explorers, Rhizophagusintraradices and Funneliformis mosseae. Each AM fungus was associated with a distinct alp gene harboring bacterial assemblage, and the alp gene abundance and Po preference of the microbiome associated with the less efficient space explorer were higher than those of the two other species. We conclude that the traits of AM fungal associated bacterial consortia cause niche differentiation. The trade-off between foraging ability and the ability to recruit effective Po mobilizing microbiomes is a mechanism that allows co-existence of AM fungal species in a single plant root and surrounding soil habitat.


Assuntos
Microbiota , Micorrizas , Voo Espacial , Micorrizas/metabolismo , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Fungos/genética , Fungos/metabolismo , Solo , Bactérias/metabolismo , Microbiologia do Solo
4.
Environ Microbiol ; 25(4): 867-879, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36588345

RESUMO

Arbuscular mycorrhizal (AM) fungi form a continuum between roots and soil. One end of this continuum is comprised of the highly intimate plant-fungus interface with intracellular organelles for nutrient exchange, while on the other end the fungus interacts with bacteria to compensate for the AM fungus' inability to take up organic nutrients from soil. How both interfaces communicate in this highly complex tripartite mutualism is widely unknown. Here, the effects of phosphate-solubilizing bacteria (PSB) Rahnella aquatilis dwelling at the surface of the extraradical hyphae of Rhizophagus irregularis was analysed based on the expression of genes involved in C-P exchange at the peri-arbuscular space (PAS) in Medicago truncatula. The interaction between AM fungus and PSB resulted in an increase in uptake and transport of Pi along the extraradical hyphae and its transfer from AM fungus to plant. In return, this was remunerated by a transfer of C from plant to AM fungus, improving the C-P exchange at the PAS. These results demonstrated that a microorganism (i.e., a PSB) developing at the hyphosphere interface can affect the C-P exchange at the PAS between plant and AM fungus, suggesting a fine-tuned communication operated between three organisms via two distantly connected interfaces.


Assuntos
Medicago truncatula , Micorrizas , Rahnella , Fósforo/metabolismo , Carbono/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Medicago truncatula/microbiologia , Rahnella/metabolismo , Fosfatos/metabolismo , Micorrizas/genética , Micorrizas/metabolismo , Raízes de Plantas/metabolismo , Bactérias/metabolismo , Solo
5.
New Phytol ; 238(6): 2578-2593, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36694293

RESUMO

The extraradical hyphae of arbuscular mycorrhizal (AM) fungi are colonized by different bacteria in natural and agricultural systems, but the mechanisms by which AM fungi interact with the hyphosphere soil microbiome and influence soil organic phosphorus (P) mobilization remain unclear. We grew Medicago in two-compartment microcosms, inoculated with Rhizophagus irregularis, or not, in the root compartment and set up P treatments (without P, with P addition as KH2 PO4 or nonsoluble phytate) in the hyphal compartment. We studied the processes of soil P turnover and characterized the microbiome functional profiles for P turnover in the hyphosphere soil by metagenomic sequencing. Compared with the bulk soil, the hyphosphere soil of R. irregularis was inhabited by a specific bacterial community and their functional profiles for P turnover was stimulated. At the species level, the shift in hyphosphere soil microbiome was characterized by the recruitment of the genome bin2.39 harbouring both gcd and phoD genes and genome bin2.97 harbouring the phoD gene, which synergistically drove nonsoluble phytate mobilization in the hyphosphere soil. Our results suggest that AM fungi recruits a specific hyphosphere soil microbiome and stimulated their functional profiles for P turnover to enhance utilization of phytate.


Assuntos
Microbiota , Micorrizas , Micorrizas/metabolismo , Fósforo/metabolismo , Solo , Ácido Fítico/metabolismo , Fungos/metabolismo , Bactérias/metabolismo , Raízes de Plantas/metabolismo , Microbiologia do Solo
6.
New Phytol ; 238(2): 859-873, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36444521

RESUMO

The mycorrhizal pathway is an important phosphorus (P) uptake pathway for more than two-thirds of land plants. The arbuscular mycorrhizal (AM) fungi-associated hyphosphere microbiome has been considered as the second genome of mycorrhizal P uptake pathway and functionality in mobilizing soil organic P (Po). However, whether there is a core microbiome in the hyphosphere and how this is implicated in mining soil Po are less understood. We established on-site field trials located in humid, semiarid, and arid zones and a microcosm experiment in a glasshouse with specific AM fungi and varying soil types to answer the above questions. The hyphosphere microbiome of AM fungi enhanced soil phosphatase activity and promoted Po mineralization in all sites. Although the assemblage of hyphosphere microbiomes identified in three climate zones was mediated by environmental factors, we detected a core set in three sites and the subsequent microcosm experiment. The core members were co-enriched in the hyphosphere and dominated by Alphaproteobacteria, Actinobacteria, and Gammaproteobacteria. Moreover, these core bacterial members aggregate into stable guilds that contributed to phosphatase activity. The core hyphosphere microbiome is taxonomically conserved and provides functions, with respect to the mineralization of Po, that AM fungi lack.


Assuntos
Microbiota , Micorrizas , Micorrizas/metabolismo , Fósforo/metabolismo , Fungos/metabolismo , Bactérias/metabolismo , Solo , Microbiologia do Solo , Monoéster Fosfórico Hidrolases/metabolismo , Raízes de Plantas/metabolismo
7.
Cancer Research and Clinic ; (6): 115-119, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-996197

RESUMO

Objective:To investigate the application of 3.0T multiparametric magnetic resonance imaging (Mp-MRI) prostate imaging-reporting and data system (PI-RADS) V2.1 score combined with prostate-specific antigen density (PSAD) in the diagnosis of prostate cancer (PCa).Methods:The clinical data of 82 patients with suspected PCa who were admitted to Nantong Second People's Hospital from May 2017 to Octorber 2021 were retrospectively analyzed. The 3.0T Mp-MRI PI-RADS V2.1 score, serum PSAD level and pathological diagnosis were obtained from all patients. The 3.0T Mp-MRI PI-RADS V2.1 score and its distribution as well as serum PSAD level between patients with pathologically diagnosed PCa and patients with prostatic hyperplasia (BPH) were compared. The diagnostic efficiency of 3.0T Mp-MRI PI-RADS V2.1 score and serum PSAD level alone and in combination for PCa was analyzed using receiver operating characteristic (ROC) curve, with pathological results as the gold standard.Results:Pathological diagnosis showed that there were 43 cases (52.44%) of PCa and 39 cases (47.56%) of BPH. There was a statistical difference in the distribution of 3.0T Mp-MRI PI-RADS V2.1 score between PCa and BPH patients ( Z = 32.25, P<0.001). The 3.0T Mp-MRI PI-RADS V2.1 score of PCa patients was higher than that of BPH patients [(4.29±0.25) points vs. (2.24±0.11) points, P < 0.001], the serum PSAD level was higher than that of BPH patients [(0.49±0.15) ng·ml -1·cm -3 vs. (0.27±0.08) ng·ml -1·cm -3, P < 0.001]. The ROC curve analysis showed that area under the curve of 3.0T Mp-MRI PI-RADS V2.1 score, serum PSAD level alone and both together for the diagnosis of PCa were 0.766 (95% CI 0.659-0.852, P < 0.001), 0.793 (95% CI 0.689- 0.874, P < 0.001) and 0.816 (95% CI 0.715-0.893, P < 0.001). Conclusions:3.0T Mp-MRI PI-RADS V2.1 score and serum PSAD level are both elevated in PCa patients. They have certain values in the diagnosis of PCa, and the combination of the two has higher diagnostic efficiency.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991758

RESUMO

Objective:To analyze the safety and effectiveness of superselective embolization of the uterine arteries in the treatment of uterine fibroids.Methods:The clinical data of 60 patients with uterine fibroids who were admitted to Zhejiang Veteran Hospital from February 2020 to February 2022 were retrospectively analyzed. These patients were divided into a control group and an observation group ( n = 30/group) according to different surgical methods. The control group underwent conventional surgery. The observation group underwent superselective embolization of the uterine arteries. Uterine size, uterine fibroid size, postoperative hormone level, and complications were compared between the two groups. Results:There was no significant difference in total response rate between the observation and control groups [93.33 (28/30) vs. 83.33 (25/30), χ2 = 1.46, P > 0.05]. After surgery, serum estradiol, luteinizing hormone, follicle-stimulating hormone, and progesterone levels in the observation group were (164.14 ± 19.97) ng/L, (2.43 ± 1.47) IU/L, (2.51 ± 1.14) IU/L, and (5.05 ± 0.43) μg/L, respectively, which were significantly lower than (190.23 ± 21.62) ng/L, (3.78 ± 1.63) IU/L, (3.94 ± 1.23) IU/L, (8.22 ± 1.35) μg/L in the control group ( t = 4.86, 3.37, 4.67, 12.25, all P < 0.05). The incidence of postoperative complications in the observation group was significantly lower than that in the control group [3.33% (1/30) vs. 20.00% (6/30), χ2 = 4.04, P < 0.05). Conclusion:Compared with conventional surgery, superselective embolization of the uterine arteries is more effective on uterine fibroids, better keep postoperative hormone level stable, and reduce or avoid short- and long-term complications. Therefore, superselective embolization of the uterine arteries for the treatment of uterine fibroids deserves the clinical promotion.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-989734

RESUMO

Objective:To investigate the effects of Neibu Huangqi Decoction combined with Kangfuxin Liquid on wound healing after hemorrhoid fistula.Methods:Randomized controlled trial. A total of 90 patients with hemorrhoid fistula surgery in Tangshan Hospital of Traditional Chinese Medicine from January 2020 to June 2021 were selected as the observation objects and divided into 2 groups by random number table method, with 45 cases in each group. The control group was treated with Kangfuxin Liquid after surgery, and the observation group was treated with Neibu Huangqi Decoction. Both groups were treated continuously for 14 days. Wound symptom score was performed before and after treatment. The levels of TNF-α, IL-6 and IL-8 were determined by ELISA. The wound healing time was observed and the wound healing rate was calculated. Adverse reactions were recorded and clinical efficacy was evaluated.Results:The total effective rate was 93.33% (42/45) in the observation group and 66.67% (30/45) in the control group, with statistical significance ( χ2=9.89, P=0.002). After treatment, the scores of pain [(0.63±0.14) vs. (0.97±0.27), t=7.50], exudation [(0.67±0.12) vs. (1.09±0.31), t=8.48], edema [(0.78±0.17) vs.(1.25±0.36), t=7.92], pruritus [(0.78±0.20) vs. (1.32±0.33), t=9.39] were lower than those in the control group ( P<0.01); serum TNF-α [(33.46±2.86) μg/L vs. (45.78±3.92) μg/L, t=25.39], IL-6 [(41.86±5.84) μg/L vs. (56.12±6.75) μg/L, t=15.98], IL-8 [(27.40±3.58) ng/L vs. (36.16±3.84) ng/L, t=16.69] were lower than those in the control group ( P<0.01). The wound healing time of the observation group was shorter than that of the control group ( t=8.60, P<0.01), and the wound healing rate was higher than that of the control group ( t=24.65, P<0.01). During treatment, the incidence of adverse reactions was 11.11% (5/45) in the observation group and 6.67% (3/45) in the control group, without statistical significance ( χ2=0.14, P=0.711). Conclusion:Neibu Huangqi Decoction combined with Kangfuxin Liquid can promote wound healing, reduce inflammatory cytokines, relieve pain and exudation, improve clinical efficacy, and have few adverse reactions.

10.
Journal of Geriatric Cardiology ; (12): 779-787, 2023.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1010209

RESUMO

BACKGROUND@#The benefits of healthy lifestyles are well recognized. However, the extent to which improving unhealthy lifestyles reduces cardiovascular disease (CVD) risk needs to be discussed. We evaluated the impact of lifestyle improvement on CVD incidence using data from the China-PAR project (Prediction for Atherosclerotic Cardiovascular Disease Risk in China).@*METHODS@#A total of 12,588 participants free of CVD were followed up for three visits after the baseline examination. Changes in four lifestyle factors (LFs) (smoking, diet, physical activity, and alcohol consumption) were assessed through questionnaires from the baseline to the first follow-up visit. Cox proportional hazard models were used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). The risk advancement periods (RAPs: the age difference between exposed and unexposed participants reaching the same incident CVD risk) and population-attributable risk percentage (PAR%) were also calculated.@*RESULTS@#A total of 909 incident CVD cases occurred over a median follow-up of 11.14 years. Compared with maintaining 0-1 healthy LFs, maintaining 3-4 healthy LFs was associated with a 40% risk reduction of incident CVD (HR = 0.60, 95% CI: 0.45-0.79) and delayed CVD risk by 6.31 years (RAP: -6.31 [-9.92, -2.70] years). The PAR% of maintaining 3-4 unhealthy LFs was 22.0% compared to maintaining 0-1 unhealthy LFs. Besides, compared with maintaining two healthy LFs, improving healthy LFs from 2 to 3-4 was associated with a 23% lower risk of CVD (HR = 0.77, 95% CI: 0.60-0.98).@*CONCLUSIONS@#Long-term sustenance of healthy lifestyles or improving unhealthy lifestyles can reduce and delay CVD risk.

11.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1007891

RESUMO

OBJECTIVE@#This study aimed to investigate the association between fruit and vegetable intake and arterial stiffness.@*METHODS@#We conducted a cohort-based study comprising 6,628 participants with arterial stiffness information in the Prediction for Atherosclerotic Cardiovascular Disease Risk in China (China-PAR) project. A semi-quantitative food-frequency questionnaire was used to assess baseline (2007-2008) and recent (2018-2021) fruit and vegetable intake. We assessed changes in fruit and vegetable intake from 2007-2008 to 2018-2021 in 6,481 participants. Arterial stiffness was measured using the arterial velocity-pulse index (AVI) and arterial pressure-volume index (API). Elevated AVI and API values were defined according to diverse age reference ranges.@*RESULTS@#Multivariable-adjusted linear regression models revealed that every 100 g/d increment in fruit and vegetable intake was associated with a 0.11 decrease in AVI ( B= -0.11; 95% confidence interval [ CI]: -0.20, -0.02) on average, rather than API ( B = 0.02; 95% CI: -0.09, 0.13). The risk of elevated AVI (odds ratio [ OR] = 0.82; 95% CI: 0.70, 0.97) is 18% lower in individuals with high intake (≥ 500 g/d) than in those with low intake (< 500 g/d). Furthermore, maintaining a high intake in the past median of 11.5 years of follow-up was associated with an even lower risk of elevated AVI compared with a low intake at both baseline and follow-up ( OR = 0.64; 95% CI: 0.49, 0.83).@*CONCLUSION@#Fruit and vegetable intake was negatively associated with arterial stiffness, emphasizing recommendations for adherence to fruit and vegetable intake for the prevention of arterial stiffness.


Assuntos
Humanos , Rigidez Vascular , Frutas , Verduras , Aterosclerose , China
12.
Plant Cell ; 34(10): 4066-4087, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35880836

RESUMO

Most plant species can form symbioses with arbuscular mycorrhizal fungi (AMFs), which may enhance the host plant's acquisition of soil nutrients. In contrast to phosphorus nutrition, the molecular mechanism of mycorrhizal nitrogen (N) uptake remains largely unknown, and its physiological relevance is unclear. Here, we identified a gene encoding an AMF-inducible ammonium transporter, ZmAMT3;1, in maize (Zea mays) roots. ZmAMT3;1 was specifically expressed in arbuscule-containing cortical cells and the encoded protein was localized at the peri-arbuscular membrane. Functional analysis in yeast and Xenopus oocytes indicated that ZmAMT3;1 mediated high-affinity ammonium transport, with the substrate NH4+ being accessed, but likely translocating uncharged NH3. Phosphorylation of ZmAMT3;1 at the C-terminus suppressed transport activity. Using ZmAMT3;1-RNAi transgenic maize lines grown in compartmented pot experiments, we demonstrated that substantial quantities of N were transferred from AMF to plants, and 68%-74% of this capacity was conferred by ZmAMT3;1. Under field conditions, the ZmAMT3;1-dependent mycorrhizal N pathway contributed >30% of postsilking N uptake. Furthermore, AMFs downregulated ZmAMT1;1a and ZmAMT1;3 protein abundance and transport activities expressed in the root epidermis, suggesting a trade-off between mycorrhizal and direct root N-uptake pathways. Taken together, our results provide a comprehensive understanding of mycorrhiza-dependent N uptake in maize and present a promising approach to improve N-acquisition efficiency via plant-microbe interactions.


Assuntos
Compostos de Amônio , Micorrizas , Compostos de Amônio/metabolismo , Regulação da Expressão Gênica de Plantas , Micorrizas/fisiologia , Nitrogênio/metabolismo , Fósforo/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Solo , Zea mays/metabolismo
13.
Sci Total Environ ; 838(Pt 2): 155997, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35588830

RESUMO

Synergies to achieve high phosphorus (P) use efficiency (PUE) and mitigate greenhouse gas (GHG) emissions are critical for developing strategies aimed toward agricultural green development. However, the potential effects of such synergies in the entire P supply chain through optimizing P management in crop production are poorly understood. In this study, a partial life cycle of a GHG emissions model was developed to quantify the P-related GHG emissions in the entire P supply chain in China. Our results showed that 16.3 kg CO2-equivalent (CO2-eq) was produced from the entire P supply chain per unit of P used for grain agriculture (maize, rice, and wheat). P-related GHG emissions in China increased more than five-fold from 1980 (7.2 Tg CO2-eq) to 2018 (44.9 Tg CO2-eq). GHG emissions were found to be strongly associated with the intensity of grain production in China, and they varied considerably across production regions owing to the differences in the P fertilizer production efficiency. Mineral P fertilizer use in crop production was the primary source of P-related GHG emissions. The results suggest that sustainable P management by matching mineral P fertilizer rates and fertilizer types with crop needs can mitigate GHG emissions by 10.8-27.7 Tg (24.0-65.1%). Moreover, this can improve PUE and reduce mineral P input by 0.7-1.4 Tg (24.0-46.0%). These findings highlight that potential synergies between high PUE and low P-related GHG emissions can be achieved via sustainable P management, thereby enhancing green agricultural development in China and other regions worldwide.


Assuntos
Fertilizantes , Gases de Efeito Estufa , Agricultura/métodos , Dióxido de Carbono/análise , China , Fertilizantes/análise , Efeito Estufa , Gases de Efeito Estufa/análise , Fósforo
14.
Sci Total Environ ; 814: 152739, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34974004

RESUMO

Sustainable phosphorus (P) management presents challenges in crop production and environmental protection; the current understanding of chemical P-fertilizer manufacturing, rock phosphate (RP) mining, P loss within supply chains, and strategies to mitigate loss is incomplete because of a fragmented understanding of P in the crop production supply chain. Therefore, we develop a knowledge-based management theoretical framework to analyze P supply chains to explore ways to mitigate China's P crisis. This framework connects upstream P industries and crop production, addressing knowledge gaps and stakeholder involvement. We demonstrate the potential to improve P use efficiency in the supply chain, thereby mitigating the P crisis using optimized P management. Our results showed that P footprint and grain production demand for RP can be reduced without yield penalty using a crop-demand-oriented P supply chain management that integrates P use in crop production, P-fertilizer manufacturing, and RP mining. Food security and P-related environment sustainability can be achieved by sharing responsibility and knowledge among stakeholders.


Assuntos
Agricultura , Fósforo , China , Conservação dos Recursos Naturais , Produção Agrícola , Fertilizantes , Abastecimento de Alimentos , Fósforo/análise
15.
Sci Total Environ ; 804: 150183, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34520915

RESUMO

Sustainable phosphorus (P) management is crucial to both food security and environmental conservation. The optimization of P input from mineral fertilizers has been advocated as an effective approach to improve P use efficiency. However, strategies for maximizing P use efficiency by linking soil-crop systems and fertilizer types with the P flow, from a whole P supply chain perspective, are lacking. In this study, a meta-analysis and substance flow analysis (SFA) were employed to evaluate the effects of different mineral P fertilizer types on crop yield and P flow from rock phosphate (RP) exploitation to P use in China. Compared to single superphosphate (SSP), triple superphosphate (TSP), and calcium magnesium phosphate (CMP), a significantly higher yield was obtained when diammonium phosphate (DAP) and monoammonium phosphate (MAP) were used 2005 onwards. However, P loss, from RP extraction to application, was 24% higher for DAP and MAP than for SSP, TSP, and CMP. DAP and MAP use led to a 6% larger P footprint than SSP, TSP, and CMP use. The P use efficiency could be improved by 22%, 36%, and 40% in wheat, maize, and rice production, respectively, by integrating the soil-crop system with mineral P fertilizer types, while P loss and P footprint could be reduced by 13% and 17%, respectively. These results indicate that P use efficiency can be significantly improved by integrating mineral P fertilizer types with soil-crop systems, providing an effective approach for RP exploitation to improve P use efficiency and alleviate the overexploitation of RP.


Assuntos
Fertilizantes , Fósforo , Agricultura , China , Produção Agrícola , Fertilizantes/análise , Minerais , Nitrogênio , Fósforo/análise , Solo
16.
Trends Plant Sci ; 27(4): 402-411, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34782247

RESUMO

More than two-thirds of terrestrial plants acquire nutrients by forming a symbiosis with arbuscular mycorrhizal (AM) fungi. AM fungal hyphae recruit distinct microbes into their hyphosphere, the narrow region of soil influenced by hyphal exudates. They thereby shape this so-called second genome of AM fungi, which significantly contributes to nutrient mobilization and turnover. We summarize current insights into characteristics of the hyphosphere microbiome and the role of hyphal exudates on orchestrating its composition. The hyphal exudates not only contain carbon-rich compounds but also promote bacterial growth and activity and influence the microbial community structure. These effects lead to shifts in function and cause changes in organic nutrient cycling, making the hyphosphere a unique and largely overlooked functional zone in ecosystems.


Assuntos
Microbiota , Micorrizas , Bactérias/metabolismo , Fungos/metabolismo , Micorrizas/metabolismo , Nitrogênio/metabolismo , Raízes de Plantas/metabolismo , Solo/química , Microbiologia do Solo
17.
Environ Microbiol Rep ; 14(1): 119-129, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34951128

RESUMO

Two-component systems (TCS) are ubiquitous among bacteria, playing key roles in signalling events. However, to what extent the TCS of Rahnella aquatilis (a Phosphate solubilizing bacteria) is influenced by the hyphosphere of the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis is totally unknown. Here, the expression of 16 genes encoding the TCS of R. aquatilis (i.e. involved in carbon-sensing and nutrient-sensing) and of eight genes regulated by the PhoR TCS (i.e. involved in inorganic and organic phosphorus mobilization) were analysed at regular intervals in presence of hyphae of R. irregularis. The study was conducted under in vitro culture conditions with phytate as the unique source of phosphorus. In presence of the AM fungus, the expression of TCS genes involved in carbon-sensing and nutrient-sensing were stimulated. Only, BaeS at 30 and 120 min, and BaeR at 60 min were inhibited. In addition, the PhoR TCS stimulated the expression of genes encoding phosphatase but inhibited the expression of genes involved in gluconic acid production. As the mechanism of coupling environmental changes with cellular physiological changes, TCS plays a pivotal role in regulating specific gene expression in R. aquatilis, recognizing environmental signals. More importantly, TCS genes may regulate bacteria response to hyphal carbon to mobilize phosphorus efficiently in the hyphosphere.


Assuntos
Micorrizas , Rahnella , Fungos , Hifas/metabolismo , Micorrizas/metabolismo , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Rahnella/metabolismo
18.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-929068

RESUMO

The application of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (Cas) can be limited due to a lack of compatible protospacer adjacent motif (PAM) sequences in the DNA regions of interest. Recently, SpRY, a variant of Streptococcus pyogenes Cas9 (SpCas9), was reported, which nearly completely fulfils the PAM requirement. Meanwhile, PAMs for SpRY have not been well addressed. In our previous study, we developed the PAM Definition by Observable Sequence Excision (PAM-DOSE) and green fluorescent protein (GFP)‍-reporter systems to study PAMs in human cells. Herein, we endeavored to identify the PAMs of SpRY with these two methods. The results indicated that 5'-NRN-3', 5'-NTA-3', and 5'-NCK-3' could be considered as canonical PAMs. 5'-NCA-3' and 5'-NTK-3' may serve as non-priority PAMs. At the same time, PAM of 5'-NYC-3' is not recommended for human cells. These findings provide further insights into the application of SpRY for human genome editing.


Assuntos
Humanos , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas , DNA , Edição de Genes/métodos , Streptococcus pyogenes/metabolismo
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-934345

RESUMO

Objective:To develop an accurate, specific and rapid and non-destructive technique for the identification of Candida auris and its relatives without destroying the cell wall. Methods:The study was conducted in Beijing Institute of Radiation Medicine in 2021. Surface-enhanced Raman spectroscopy (SERS) substrates were prepared by sodium citrate reduction. Through SERS, the collected SERS fingerprint spectra were analyzed by orthogonal partial least-squares-discrimination analysis (OPLS-DA) using SIMCA 14.1 (Umetrics, Sweden). Four strains of Candida auris, 4 strains of Candida heamulonii, 3 strains of Candida pseudohaemulonii and 4 strains of Candida duobushaemulonii were effectively identified and distinguished. Results:Within the 95% confidence interval, the sample analysis results presented an oval. The four Candida species detected in this study could be well separated. R2X(cum)=0.629, R2Y(cum)=0.947, Q2(cum)=0.915. R2X, R2Y and Q2 all>0.5 and closed to 1, suggesting that the model in this study was well established, and had good prediction ability. The results of the 10-fold-cross validation showed that the accuracy of both the model training data and test data are 100%, indicating that the model established in this research had good classification capabilities. Conclusions:This research has developed a new technique that can identify Candida auris and its relatives in a highly accuracy, specific and rapid way without destroying the cell wall. Being cost-effective and easy to operate, this technique has great potential to be applied in clinical fungal testing.

20.
Front Plant Sci ; 12: 780454, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956276

RESUMO

Maximizing the function of indigenous arbuscular mycorrhizal (AM) fungi by choosing specific crop genotypes offers one of the few untapped opportunities to improve the sustainability of agriculture. In this study, the differences in mycorrhizal responsiveness (MR) in plant growth and shoot phosphorus (P) content among cotton (Gossypium spp. L.) genotypes from different release dates were compared and then the relationships between MR and P uptake-related traits were determined. The experimental design in a greenhouse included 24 genotypes released from 1950 to present in Xinjiang Province, inoculation with or without AM fungi, and P levels (15 and 150 mg P kg-1 added as KH2PO4). Results showed that the modern cotton genotypes exhibited a higher degree of mycorrhizal colonization, the hyphal length density (HLD), and mycorrhizae-induced changes in shoot growth than the old genotypes when inoculated with indigenous AM fungi at both the P levels. Moreover, MR was highly correlated with the HLD at low P levels and the HLD may provide useful insights for future cotton breeding aimed at delivering crop genotypes that can benefit more from AM fungi.

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