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1.
J Agric Food Chem ; 72(14): 7794-7806, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38561246

RESUMO

To investigate the effects of fertilization methods and types on wheat rhizosphere microorganisms, macroelement (N, K) and microelement (Zn) fertilizers were applied on wheat by foliar spraying (FS) and root irrigation (RI) methods in a field experiment. The results indicated that fertilization methods and types can have significant impacts on the diversity and structure of rhizospheric microorganisms in wheat. The application method produced more significant effects than the fertilizer type. RI-N played a more important role in improving the wheat yield and quality and affected the changes in some nitrogen-fixing bacterial communities. Finally, eight strains of bacteria belonging to Pseudomonas azotoformans and P. cedrina showed positive effects on the growth of wheat seedlings. Overall, our study provides a better understanding of the dynamics of wheat rhizosphere microbial communities and their relation to fertilization, yield, and quality, showing that plant growth-promoting rhizobacteria with nitrogen fixing may be a potential approach for more sustainable agriculture production.


Assuntos
Microbiota , Triticum , Rizosfera , Nitrogênio/análise , Fertilizantes/análise , Fertilização , Solo/química , Microbiologia do Solo
2.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612464

RESUMO

Immunodominant alloantigens in pig sperm membranes include 15 known gene products and a previously undiscovered Mr 20,000 sperm membrane-specific protein (SMA20). Here we characterize SMA20 and identify it as the unannotated pig ortholog of PMIS2. A composite SMA20 cDNA encoded a 126 amino acid polypeptide comprising two predicted transmembrane segments and an N-terminal alanine- and proline (AP)-rich region with no apparent signal peptide. The Northern blots showed that the composite SMA20 cDNA was derived from a 1.1 kb testis-specific transcript. A BLASTp search retrieved no SMA20 match from the pig genome, but it did retrieve a 99% match to the Pmis2 gene product in warthog. Sequence identity to predicted PMIS2 orthologs from other placental mammals ranged from no more than 80% overall in Cetartiodactyla to less than 60% in Primates, with the AP-rich region showing the highest divergence, including, in the extreme, its absence in most rodents, including the mouse. SMA20 immunoreactivity localized to the acrosome/apical head of methanol-fixed boar spermatozoa but not live, motile cells. Ultrastructurally, the SMA20 AP-rich domain immunolocalized to the inner leaflet of the plasma membrane, the outer acrosomal membrane, and the acrosomal contents of ejaculated spermatozoa. Gene name search failed to retrieve annotated Pmis2 from most mammalian genomes. Nevertheless, individual pairwise interrogation of loci spanning Atp4a-Haus5 identified Pmis2 in all placental mammals, but not in marsupials or monotremes. We conclude that the gene encoding sperm-specific SMA20/PMIS2 arose de novo in Eutheria after divergence from Metatheria, whereupon rapid molecular evolution likely drove the acquisition of a species-divergent function unique to fertilization in placental mammals.


Assuntos
Placenta , Sêmen , Masculino , Feminino , Gravidez , Suínos , Animais , Camundongos , DNA Complementar , Espermatozoides , Eutérios , Alanina , Isoantígenos/genética , Fertilização/genética
3.
Reprod Domest Anim ; 59(4): e14566, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38627959

RESUMO

Early pregnancy loss is a primary cause of low reproductive rates in dairy cows, posing severe economic losses to dairy farming. The accurate diagnosis of dairy cows with early pregnancy loss allows for oestrus synchronization, shortening day open, and increasing the overall conception rate of the herd. Several techniques are available for detecting early pregnancy loss in dairy cows, including rectal ultrasound, circulating blood progesterone, and pregnancy-associated glycoproteins (PAGs). Yet, there is a need to improve on existing techniques and develop novel strategies to identify cows with early pregnancy loss accurately. This manuscript reviews the applications of rectal ultrasound, circulating blood progesterone concentration, and PAGs in the diagnosis of pregnancy loss in dairy cows. The manuscript also discusses the recent progress of new technologies, including colour Doppler ultrasound (CDUS), interferon tau-induced genes (ISGs), and exosomal miRNA in diagnosing pregnancy loss in dairy cows. This study will provide an option for producers to re-breed cows with pregnancy loss, thereby reducing the calving interval and economic costs. Meanwhile, this manuscript might also act as a reference for exploring more economical and precise diagnostic technologies for early pregnancy loss in dairy cows.


Assuntos
Doenças dos Bovinos , Progesterona , Gravidez , Feminino , Bovinos , Animais , Aborto Animal/diagnóstico , Reprodução , Fertilização , Glicoproteínas , Inseminação Artificial/veterinária , Doenças dos Bovinos/diagnóstico
4.
Sci Rep ; 14(1): 6672, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509150

RESUMO

Soybean, belonging to legumes, has a specific ability to biological nitrogen fixation, which can be reinforced by seeds inoculation. However, support with a starter dose of mineral nitrogen fertilizer may be necessary to achieve high seed yields. A four-year field experiment was conducted to determine the effect of mineral N fertilization (0, 30, 60 kg ha-1), seed inoculation with two commercial inoculants and combinations of these treatments on yield components and yielding of soybean in conditions of south-western part of Poland. The synergistic effect of mineral fertilization at dose 30 kg ha-1 and inoculation on soybean productivity was the most beneficial. Similar effects were observed when 60 kg N ha-1 was applied both separately and with inoculation. However, due to the environmental impact of mineral fertilizers and to promote plants to biological nitrogen fixation (BNF), it is advisable to use lower doses of N fertilizer (at 30 kg ha-1) and inoculate soybean seeds in agro- climatic conditions of south-western Poland. Therefore, based on this study we recommend to apply starter dose of N and inoculation.


Assuntos
Soja , Nitrogênio , Fertilizantes , Polônia , Sementes , Minerais , Fertilização
5.
BMC Pregnancy Childbirth ; 24(1): 212, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509466

RESUMO

BACKGROUND: Women having experienced infertility over a period usually decide on an option for an invitro fertilisation treatment (IVF). However, in the quest to seek help and to be part of motherhood, they sometimes become unsuccessful in their fertility journey. The researchers aimed to explore the meanings and emotions attached to infertility and unsuccessful invitro fertilisation (IVF) treatment among Ghanaian women, as this area of inquiry is less explored in Africa and specifically in the Ghanaian context. METHODS: The study followed a qualitative approach and drew inspiration from the Heideggerian phenomenological philosophy and design. Six (6) women, aged between 29 and 40 years, who had experienced at least one unsuccessful IVF cycle, were purposefully selected from a private specialist fertility hospital in Kumasi, Ghana. One-on-one interviews were conducted with the participants, and the interviews were transcribed verbatim. The collected data was analyzed using Van Manen six-step framework, which helped to uncover the existential meanings and interpretations these women ascribed to their experiences. RESULTS: The results of the study revealed four main themes that were deemed essential aspects of meaning for the participants. These themes were: (1) Experiencing an Existential Faith and Hope. The participants described their journey through infertility and invitro fertilisation (IVF) treatment as a profound test of their existential faith and hope finding strength in maintaining a positive outlook despite the challenges and setbacks they faced., (2) Facing up to the Angst: This theme highlights the participants' courage in confronting the emotional dimensions of their struggles. The women acknowledged and confronted their anxieties, fears, and emotional distress associated with their infertility and unsuccessful IVF treatment., (3). Non-disclosedness: This theme refers to the participants' experiences of keeping their struggles with IVF treatment private, often due to societal and cultural factors. (4). Endured feelings of inadequacy of being-in-the-world-of-motherless: Participants expressed feelings of inadequacy, self-doubt, and a sense of being incomplete due to their inability to conceive and fulfill the societal role of motherhood. Their narratives revealed the profound impact of societal expectations on their self-perception and identity. CONCLUSION: The study's findings reveal insights into the experiences and interpretations of infertility and unsuccessful IVF treatment among Ghanaian women. Employing Heideggerian hermeneutics, the research elucidates the diverse existential, emotional, and societal aspects inherent in the struggles of infertility. The multifaceted nature of these women's journeys underscores the significance of a comprehensive approach to infertility care that recognizes the cultural, social, emotional, and existential dimensions of the IVF process. Additionally, the study emphasizes the necessity for culturally sensitive support systems and interventions to address the unique challenges faced by this population.


Assuntos
Fertilização In Vitro , Infertilidade , Humanos , Feminino , Adulto , Gana , Hermenêutica , Fertilização In Vitro/psicologia , Infertilidade/terapia , Fertilização
6.
Sci Rep ; 14(1): 6396, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493223

RESUMO

Knowledge about paternal-effect-genes (PEGs) (genes whose expression in the progeny is influenced by paternal factors present in the sperm) in fish is very limited. To explore this issue, we used milt cryopreservation as a specific challenge test for sperm cells, thus enabling selection amidst cryo-sensitivity. We created two groups of Eurasian perch (Perca fluviatilis) as a model - eggs fertilized either with fresh (Fresh group) or cryopreserved (Cryo group) milt from the same male followed by phenotypic-transcriptomic examination of consequences of cryopreservation in obtained progeny (at larval stages). Most of the phenotypical observations were similar in both groups, except the final weight which was higher in the Cryo group. Milt cryopreservation appeared to act as a "positive selection" factor, upregulating most PEGs in the Cryo group. Transcriptomic profile of freshly hatched larvae sourced genes involved in the development of visual perception and we identified them as PEGs. Consequently, larvae from the Cryo group exhibited enhanced eyesight, potentially contributing to more efficient foraging and weight gain compared to the Fresh group. This study unveils, for the first time, the significant influence of the paternal genome on the development of the visual system in fish, highlighting pde6g, opn1lw1, and rbp4l as novel PEGs.


Assuntos
Percas , Animais , Masculino , Percas/genética , Sêmen , Criopreservação , Fertilização , Espermatozoides/fisiologia , Larva
7.
PLoS Genet ; 20(3): e1011186, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38483976

RESUMO

Egg activation, representing the critical oocyte-to-embryo transition, provokes meiosis completion, modification of the vitelline membrane to prevent polyspermy, and translation of maternally provided mRNAs. This transition is triggered by a calcium signal induced by spermatozoon fertilization in most animal species, but not in insects. In Drosophila melanogaster, mature oocytes remain arrested at metaphase-I of meiosis and the calcium-dependent activation occurs while the oocyte moves through the genital tract. Here, we discovered that the oenocytes of fruitfly females are required for egg activation. Oenocytes, cells specialized in lipid-metabolism, are located beneath the abdominal cuticle. In adult flies, they synthesize the fatty acids (FAs) that are the precursors of cuticular hydrocarbons (CHCs), including pheromones. The oenocyte-targeted knockdown of a set of FA-anabolic enzymes, involved in very-long-chain fatty acid (VLCFA) synthesis, leads to a defect in egg activation. Given that some but not all of the identified enzymes are required for CHC/pheromone biogenesis, this putative VLCFA-dependent remote control may rely on an as-yet unidentified CHC or may function in parallel to CHC biogenesis. Additionally, we discovered that the most posterior ventral oenocyte cluster is in close proximity to the uterus. Since oocytes dissected from females deficient in this FA-anabolic pathway can be activated in vitro, this regulatory loop likely operates upstream of the calcium trigger. To our knowledge, our findings provide the first evidence that a physiological extra-genital signal remotely controls egg activation. Moreover, our study highlights a potential metabolic link between pheromone-mediated partner recognition and egg activation.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Feminino , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Cálcio/metabolismo , Fertilização , Oócitos/metabolismo , Feromônios/genética , Feromônios/metabolismo
8.
Ying Yong Sheng Tai Xue Bao ; 35(1): 55-61, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511440

RESUMO

Improving soil fertility is one of the key approaches for ecological restoration of the wind-sand area in northwest Liaoning Province. Taking wind-sand area in northwest Liaoning Province as test object, we conducted a fertilization experiment with treatments of inorganic fertilizer (nitrogen, phosphorus and potassium fertilizers), organic fertilizer, combined application of organic and inorganic fertilizers, and organic fertilizer combined with a biologically organic matrix (γ-polyglutamic acid), and no fertilizer as control. We measured soil organic matter content and extractable cations concentrations, vegetation coverage, and biomass under different fertilization treatments and determine the suitable fertilization mode. The results showed that compared to the control, inorganic fertilizer rapidly increased vegetation coverage and biomass, but high levels of inorganic fertilizer (150 kg N·hm-2) led to soil acidification and Ca2+ leaching. Organic fertilizer increased soil organic matter content, exchangeable K+, Ca2+, and Mg2+ contents, as well as coverage and biomass vegetation, especially combined with γ-polyglutamic acid. Overall, the combination of low levels of inorganic fertilizer (50 kg N·hm-2) and moderate levels of organic fertilizer (30000 kg·hm-2) was the best fertilization practice for the rapid and stable restoration of grassland in wind-sand area. Moreover, the extra addition of γ-polyglutamic acid (60 kg·hm-2)could effectively improve soil fertility.


Assuntos
Agricultura , Solo , Agricultura/métodos , Fertilizantes , Areia , Pradaria , Ácido Poliglutâmico , China , Nitrogênio/análise , Fertilização
9.
Int J Mol Sci ; 25(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542248

RESUMO

Strigolactones (SLs) were recently defined as a novel class of plant hormones that act as key regulators of diverse developmental processes and environmental responses. Much research has focused on SL biosynthesis and signaling in roots and shoots, but little is known about whether SLs are produced in early developing seeds and about their roles in ovule development after fertilization. This study revealed that the fertilized ovules and early developing pericarp in Xanthoceras sorbifolium produced minute amounts of two strigolactones: 5-deoxystrigol and strigol. Their content decreased in the plants with the addition of exogenous phosphate (Pi) compared to those without the Pi treatment. The exogenous application of an SL analog (GR24) and a specific inhibitor of SL biosynthesis (TIS108) affected early seed development and fruit set. In the Xanthoceras genome, we identified 69 potential homologs of genes involved in SL biological synthesis and signaling. Using RNA-seq to characterize the expression of these genes in the fertilized ovules, 37 genes were found to express differently in the fertilized ovules that were aborting compared to the normally developing ovules. A transcriptome analysis also revealed that in normally developing ovules after fertilization, 12 potential invertase genes were actively expressed. Hexoses (glucose and fructose) accumulated at high concentrations in normally developing ovules during syncytial endosperm development. In contrast, a low ratio of hexose and sucrose levels was detected in aborting ovules with a high strigolactone content. XsD14 virus-induced gene silencing (VIGS) increased the hexose content in fertilized ovules and induced the proliferation of endosperm free nuclei, thereby promoting early seed development and fruit set. We propose that the crosstalk between sugar and strigolactone signals may be an important part of a system that accurately regulates the abortion of ovules after fertilization. This study is useful for understanding the mechanisms underlying ovule abortion, which will serve as a guide for genetic or chemical approaches to promote seed yield in Xanthoceras.


Assuntos
Compostos Heterocíclicos com 3 Anéis , Lactonas , Óvulo Vegetal , Sapindaceae , Óvulo Vegetal/genética , Fertilização/genética , Sementes , Sapindaceae/genética , Hexoses/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Sci Total Environ ; 924: 171523, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38453078

RESUMO

Vegetable production is commonly accompanied by high nitrogen fertilizer rates but low nitrogen use efficiency in China. Reduced fertilization has been frequently recommended in existing studies as an efficient measurement to avoid large amount of nutrient loss and subsequent nonpoint source pollution. However, the reported responses of vegetable yield and nitrogen losses to reduced fertilization rates varied in a large range, which has resulted into large uncertainties in the potential benefits of those recommended reduction rates. Thus, we constructed the relationship between responses of nitrogen losses and vegetable yield to reduced nitrogen fertilization rates to determine the optimal range of reduction rates for nitrogen fertilization in a proportional form based on data reported in literatures across China's mainland, and evaluated the roles of greenhouse, managing options, and vegetable species on the responses. The relationships were constructed separately for 4 subregions: Northern arid and semiarid, loess plateau regions (NSL), Temperate monsoon zone (TMZ), Southeast monsoon zone (SMZ), Southwest zone (SWZ). The optimal nitrogen fertilizer reduction range for the TMZ, SMZ and SWZ were 51 % to 67 %, 40 % to 66 % and 54 % to 80 %, respectively and no reduction for NSL. Vegetable yields were not be sacrificed when fertilizations were reduced within the optimal ranges. Greenhouse and managing options showed no significant effect on the responses of both vegetable yield and nitrogen losses by the optimal reduction range but vegetable species played a relatively important role on the responses of vegetable yield. This indicated that the optimal reduction rates can be effective on reducing nitrogen loss in both open-field and greenhouse conditions across China's mainland without extra managing options. Therefore, the optimal reduction rates can still serve as a good starting point for making regional plans of nitrogen reduction that help balancing the chasing of high vegetable yield and low nitrogen loss.


Assuntos
Agricultura , Verduras , Agricultura/métodos , Fertilizantes , Nitrogênio/análise , China , Fertilização , Solo
11.
Sci Total Environ ; 924: 171581, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461973

RESUMO

Nitrogen (N) fertilization is crucial for maintaining plant productivity. Clonal plants can share resources between connected ramets through clonal integration influencing microbial communities and regulating soil biogeochemical cycling, especially in the rhizosphere. However, the effect of various N fertilization practices on microbial communities in the rhizosphere of clonal ramets remain unknown. In this study, clonal fragments of Moso bamboo (Phyllostachys edulis), consisting of a parent ramet, an offspring ramet, and an interconnecting rhizome, were established in the field. NH4NO3 solution was applied to the parent, offspring ramets or rhizomes to investigate the effect of fertilization practices on the structure and function of rhizosphere microbial communities. The differences in N availability, microbial biomass and community composition, and abundance of nitrifying genes among rhizosphere soils of ramets gradually decreased during the rapid growth of Moso bamboo, irrespective of fertilization practice. The soil N availability variation, particularly in NO3-, caused by fertilization practices altered the rhizosphere microbial community. Soil N availability and stable microbial biomass N in parent fertilization were the highest, being 9.0 % and 18.7 %, as well as 60.8 % and 90.4 % higher than rhizome and offspring fertilizations, respectively. The microbial network nodes and links in rhizome fertilization were 1.8 and 7.5 times higher than in parent and offspring fertilization, respectively. However, the diversity of bacterial community and abundance of nitrifying and denitrifying genes were the highest in offspring fertilization among three practices, which may be associated with increased N loss. Collectively, the rhizosphere microbial community characteristics depended on fertilization practices by altering the clonal integration of N in Moso bamboo. Parent and rhizome fertilization were favorable for N retention in plant-soil system and resulted in more stable microbial functions than offspring fertilization. Our findings provide new insights into precision fertilization for the sustainable Moso bamboo forest management.


Assuntos
Microbiota , Nitrogênio , Rizoma , Poaceae , Microbiologia do Solo , Solo , Fertilização
12.
Arch Gynecol Obstet ; 309(5): 2137-2141, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38478159

RESUMO

BACKGROUND: Misoprostol is a well-studied medical treatment for early pregnancy loss (EPL), with success rates ranging between 70 and 90%. However, treatment failure is associated with major patient discomfort, including the need for surgical intervention to evacuate the uterus. It was previously reported that medical treatment was especially successful among women who conceived after in vitro fertilization (IVF). We aimed to study if there is a difference in rates of medical treatment failures for EPL between pregnancies conceived by IVF and spontaneous pregnancies. METHODS: In this retrospective cohort study, we included all women who underwent medical treatment for EPL at our institute between 07/2015 and 12/2020. Treatment outcome was compared between IVF and spontaneous pregnancies. Treatment failure was defined as a need for surgical intervention, namely, dilation & curettage (D&C) and/or hysteroscopy, due to retained products of conception, which was defined as a gestational sac or endometrial thickness greater than 15 mm in a TVS scan. RESULTS: Overall, 775 patients were included, of which 195 (169/775 = 25.1%) ultimately required surgical intervention. There was no difference between the study groups in the rate of treatment failure. However, among IVF pregnancies, the rate of emergency D&C was lower (3.6% vs. 9.8%, p = 0.001), compared to spontaneous group. CONCLUSION: In cases of medical treatment for EPL, IVF pregnancies had no differences in rates of treatment failure compared to spontaneous pregnancies. That being said, IVF pregnancies have lower chances to undergo emergency D&C, compared to spontaneous pregnancies.


Assuntos
Aborto Espontâneo , Misoprostol , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Fertilização In Vitro , Fertilização , Resultado da Gravidez
13.
Sci Total Environ ; 926: 171809, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38513845

RESUMO

Soil cadmium (Cd) can affect crop growth and food safety, and through the enrichment in the food chain, it ultimately poses a risk to human health. Reducing the re-mobilization of Cd caused by the release of protons and acids by crops and microorganisms after stabilization is one of the significant technical challenges in agricultural activities. This study aimed to investigate the re-mobilization of stabilized Cd within the clay mineral-bound fraction of soil and its subsequent accumulation in crops utilizing nitrogen ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N), at 60 and 120 mg kg-1. Furthermore, the study harvested root exudates at various growth stages to assess their direct influence on the re-mobilization of stabilized Cd and to evaluate the indirect effects mediated by soil microorganisms. The results revealed that, in contrast to the NO3--N treatment, the NH4+-N treatment significantly enhanced the conversion of clay mineral-bound Cd in the soil to NH4NO3-extractable Cd. It also amplified the accumulation of Cd in edible amaranth, with concentrations in roots and shoots rising from 1.7-6.0 mg kg-1 to 4.3-9.8 mg kg-1. The introduction of NH4+-N caused a decrease in the pH value of the rhizosphere soil and stimulated the production and secretion organic and amino acids, such as oxalic acid, lactic acid, stearic acid, succinic acid, and l-serine, from the crop roots. Furthermore, compared to NO3--N, the combined interaction of root exudates with NH4+-N has a more pronounced impact on the abundance of microbial genes associated with glycolysis pathway and tricarboxylic acid cycle, such as pkfA, pfkB, sucB, sucC, and sucD. The effects of NH4+-N on crops and microorganisms ultimately result in a significant increase in the re-mobilization of stabilized Cd. However, the simulated experiments showed that microorganisms only contribute to 3.8-6.6 % of the re-mobilization of clay mineral-bound Cd in soil. Therefore, the fundamental strategy to inhibit the re-mobilization of stabilized Cd in vegetable cultivation involves the regulation of proton and organic acid secretion by crops.


Assuntos
Poluentes do Solo , Solo , Humanos , Solo/química , Cádmio/análise , Argila , Nitrogênio/metabolismo , Compostos Orgânicos/metabolismo , Produtos Agrícolas/metabolismo , Minerais/metabolismo , Fertilização , Poluentes do Solo/análise
14.
Sci Total Environ ; 926: 171865, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38518824

RESUMO

Atmospheric nitrogen (N) deposition in Mediterranean sclerophyllous forests of Holm oak (Quercus rotundifolia, Q. ilex) in Spain often exceeds empirical critical loads established for ecosystem conservation. There are still uncertainties on the capacity of canopy retention and uptake of the atmospheric N deposited of these forests. Studying and analysing all the forest nitrogen-cycle processes is essential to understand the potential effect of N deposition in these ecosystems. This study conducted a year-long short-term fertilisation experiment with labelled ammonium (15N-NH4) and nitrate (15N-NO3) to estimate foliar N absorption rates and assess the influence of leaf phenology and meteorological seasonal variations. Fertilising solutions were prepared to simulate low and high wet N deposition concentration, based on data reported from previous studies. Additionally, ecophysiological and meteorological measurements were collected to explore potential relationships between absorption rates, plant activity, and weather conditions. The results showed that Holm oak leaves were able to absorb both oxidised and reduced N compounds, with higher rates of NH4+ absorption. N recovery of both NH4+ and NO3- was higher in the low concentration treatments, suggesting reduced effectiveness of absorption as concentration increases. Foliar absorption rates were leaf-age dependent, with the highest values observed in young developing leaves. Foliar uptake showed seasonal changes with a clear reduction during the summer, linked to drought and dry weather conditions, and showing also smaller leaf net assimilation and stomatal conductance. During the rest of the year, foliar N absorption was not clearly associated to plant physiological activity but with environmental conditions. Our findings suggest that Holm oak canopies could absorb an important part of the incoming N deposition, but this process is compound, season and leaf phenology dependent. Further research is therefore needed to better understand and model this part of the N cycle.


Assuntos
Ecossistema , Quercus , Nitrogênio/análise , Florestas , Espanha , Plantas , Folhas de Planta/química , Fertilização , Quercus/fisiologia , Árvores
15.
Sci Total Environ ; 926: 172082, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38554958

RESUMO

Two main challenges which human society faces for sustainable development goals are the maintenance of food security and mitigation of greenhouse gas (GHG) emissions. Here, we examined the impacts of six fertilization treatments including unfertilized control (CK), mineral nitrogen (N, 90 kg N ha-1), mineral N plus 30 kg P ha-1 phosphorus (NP), NP combined with 3.75 Mg ha-1 straw (NP + Str), farmyard manure (Man, 75 Mg ha-1), and NP combined with manure (NP + Man) on crop productivity and carbon emissions (soil GHG emission; GHGI, yield-based GHG intensity; NGHGB, net GHG balance; carbon footprint, CF) in a maize-wheat cropping system during two years (April 2018-June 2020) in a semi-arid continental climate after 40 years of fertilization in the Northwest China. Manure and straw increased total GHG by 38-60 % compared to the mineral fertilizers alone, which was mainly due to the 49-80 % higher direct emissions of carbon dioxide (CO2) rather than nitrous oxide (N2O). Compared to the N fertilizer alone, organic amendments and NP increased cumulative energy yield by 134-202 % but decreased GHGI by 38-55 %, indicating that organic fertilizers increased crop productivity at the cost of higher GHG emissions. When the soil organic carbon changes (ΔSOC) were accounted for in the C emission balance, manure application acted as a net C sink due to the NGHGB recorded with -123 kg CO2-eq ha-1 year-1. When producing the same yield and economic benefits, the manure and straw addition decreased the CF by 59-85 % compared to N fertilization alone. Overall, the transition from mineral to organic fertilization in the semi-arid regions is a two-way independent solution to increase agricultural productivity along with the reduction of C emissions.


Assuntos
Gases de Efeito Estufa , Solo , Humanos , Pegada de Carbono , Zea mays , Triticum , Fertilizantes , Esterco , Dióxido de Carbono/análise , Carbono , Agricultura , Minerais , China , Óxido Nitroso/análise , Fertilização
16.
J Environ Manage ; 356: 120629, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518492

RESUMO

The preservation of cultivated land quality stands as a vital prerequisite for ensuring food security and sustainability. In the black soil area of northeast China, a large amount of fertilizer was used to stabilize grain production in its early stages, which damaged soil structure and polluted the ecological environment. Based on the panel data of fertilization intensity of 48 districts and counties in Heilongjiang Province from 2010 to 2020, this study takes the implementation of the "Three-Year Action Plan for the Protection of Black Soil Farmland in Heilongjiang Province for the (2018-2020)" (TYAP) policy as a natural experiment, and uses the difference-in-differences (DiD) method to identify the causal effect of the policy on the local fertilization intensity. The results of the empirical study showed that the implementation of the TYAP policy significantly reduced the fertilization intensity of the black soil cultivated land implemented by the policy during the implementation period, which resulted in a decrease of 11.97% on average compared with the areas without the policy implementation. Several robustness tests provided additional confirmation of the aforementioned findings. This study further revealed that the policy mitigated fertilization intensity by fostering advancements in agricultural mechanization.


Assuntos
Agricultura , Solo , Solo/química , Fazendas , Políticas , China , Fertilização
17.
J Environ Manage ; 356: 120718, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537467

RESUMO

Global climate change is predicted to increase exogenous N input into terrestrial ecosystems, leading to significant changes in soil C-cycling. However, it remains largely unknown how these changes affect soil C-cycling, especially in semi-arid grasslands, which are one of the most vulnerable ecosystems. Here, based on a 3-year field study involving N additions (0, 25, 50, and 100 kg ha-1 yr-1 of urea) in a semi-arid grassland on the Loess Plateau, we investigated the impact of urea fertilization on plant characteristics, soil properties, CO2 and CH4 emissions, and microbial C cycling genes. The compositions of genes involved in C cycling, including C fixation, degradation, methanogenesis, and methane oxidation, were determined using metagenomics analysis. We found that N enrichment increased both above- and belowground biomasses and soil organic C content, but this positive effect was weakened when excessive N was input (N100). N enrichment also altered the C-cycling processes by modifying C-cycle-related genes, specifically stimulating the Calvin cycle C-fixation process, which led to an increase in the relative abundance of cbbS, prkB, and cbbL genes. However, it had no significant effect on the Reductive citrate cycle and 3-hydroxypropionate bi-cycle. N enrichment led to higher soil CO2 and CH4 emissions compared to treatments without added N. This increase showed significant correlations with C degradation genes (bglA, per, and lpo), methanogenesis genes (mch, ftr, and mcr), methane oxidation genes (pmoA, pmoB, and pmoC), and the abundance of microbial taxa harboring these genes. Microbial C-cycling genes were primarily influenced by N-induced changes in soil properties. Specifically, reduced soil pH largely explained the alterations in methane metabolism, while elevated available N levels were mainly responsible for the shift in C fixation and C degradation genes. Our results suggest that soil N enrichment enhances microbial C-cycling processes and soil CO2 and CH4 emissions in semi-arid ecosystems, which contributes to more accurate predictions of ecosystem C-cycling under future climate change.


Assuntos
Ecossistema , Pradaria , Dióxido de Carbono/análise , Solo/química , Metano/análise , Fertilização
18.
Oecologia ; 204(3): 689-704, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38478083

RESUMO

Subarctic ecosystems are subjected to increasing nitrogen (N) enrichment and disturbances that induce particularly strong effects on plant communities when occurring in combination. There is little experimental evidence on the longevity of these effects. We applied N-fertilization (40 kg urea-N ha-1 year-1 for 4 years) and disturbance (removal of vegetation and organic soil layer on one occasion) in two plant communities in a subarctic forest-tundra ecotone in northern Finland. Within the first four years, N-fertilization and disturbance increased the share of deciduous dwarf shrubs and graminoids at the expense of evergreen dwarf shrubs. Individual treatments intensified the other's effect resulting in the strongest increase in graminoids under combined N-fertilization and disturbance. The re-analysis of the plant communities 15 years after cessation of N-fertilization showed an even higher share of graminoids. 18 years after disturbance, the total vascular plant abundance was still substantially lower and the share of graminoids higher. At the same point, the plant community composition was the same under disturbance as under combined N-fertilization and disturbance, indicating that multiple perturbations no longer reinforced the other's effect. Yet, complex interactions between N-fertilization and disturbance were still detected in the soil. We found higher organic N under disturbance and lower microbial N under combined N-fertilization and disturbance, which suggests a lower bioavailability of N sources for soil microorganisms. Our findings support that the effects of enhanced nutrients and disturbance on subarctic vegetation persist over decadal timescales. However, they also highlight the complexity of plant-soil interactions that drive subarctic ecosystem responses to multiple perturbations across varying timescales.


Assuntos
Ecossistema , Tundra , Plantas , Solo , Fertilização
19.
PLoS One ; 19(3): e0299299, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512895

RESUMO

This study examines the influence of lag fertilization techniques on Pakistani wheat production, highlighting the need to understand and mitigate the environmental impacts of farming methods. The basic purpose of this study is to investigate the impact of CO2 emission from fertilization and other factors on wheat production in Pakistan, using a time series of data from 1990 to 2020. CO2 emission from fertilization (CO2EF) is estimated using the default values provided by the IPCC guidelines. The ARDL approach analyses the short-run and long-run effects of CO2EF, technology level, energy use, agricultural land, and agricultural labor on wheat production. The results show that all factors have significantly impacted wheat production in Pakistan at levels of 1% and 5% significance, both in the short and long run. These findings suggest that reducing CO2EF, technology level, energy use, agricultural land, and agricultural labor on wheat production can help to increase wheat production in Pakistan. The study also highlights the importance of adopting sustainable and efficient fertilization practices, exploring alternative fertilizers, and using crop rotation systems to mitigate the adverse effects of carbon emissions from nitrogen fertilization, energy use, and the use of technology. These measures can contribute to a more sustainable and climate-resilient agriculture sector in Pakistan.


Assuntos
Carbono , Triticum , Carbono/análise , Dióxido de Carbono/análise , Agricultura/métodos , Fertilização
20.
Int J Gynaecol Obstet ; 165(1): 1-8, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38426290

RESUMO

The preconception period is a unique and opportunistic time in a woman's life when she is motivated to adopt healthy behaviors that will benefit her and her child, making this time period a critical "window of opportunity" to improve short- and long-term health. Improving preconception health can ultimately improve both fetal and maternal outcomes. Promoting health before conception has several beneficial effects, including an increase in seeking antenatal care and a reduction in neonatal mortality. Preconception health is a broad concept that encompasses the management of chronic diseases, including optimal nutrition, adequate consumption of folic acid, control of body weight, adoption of healthy lifestyles, and receipt of appropriate vaccinations. Use of the FIGO Preconception Checklist, which includes the key elements of optimal preconception care, will empower women and their healthcare providers to better prepare women and their families for pregnancy.


Assuntos
Mães , Cuidado Pré-Concepcional , Recém-Nascido , Criança , Gravidez , Feminino , Humanos , Masculino , Lista de Checagem , Cuidado Pré-Natal , Fertilização
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