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Ant evolutionary success depends mainly on the coordination of colony members, who recognize nestmates based on the cuticular hydrocarbon (CHC) profile of their epicuticle. While several studies have examined variations in this crucial factor for colony identity, few have investigated the anthropic impact on CHC profiles, and none have focused on Lasius paralienus. Here, we surveyed the changes in L. paralienus CHC assemblages across agroecosystems and assessed whether different vineyard management influences these profiles. Soil sampling within ant nests and in close surroundings was performed to measure microhabitat variations. Our results show that the cuticular chemical composition of Lasius paralienus is mainly affected by the differences between areas, with an existing but unclear anthropic influence on them. Normalized soil respiration partially explains these interarea variations. Irrespective of the conventional or organic management, human activities in agroecosystems mostly impacted L. paralienus linear alkanes, a specific class of CHCs known to play a major role against dehydration, but also affected the abundance of compounds that can be pivotal for maintaining the colony identity. Our findings suggest that vineyard practices primarily affect features of the ant cuticle, potentially enhancing microclimate adaptations. Still, the potential effects as disruptive factors need further investigation through the implementation of behavioral bioassays.
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Formigas , Hidrocarbonetos , Formigas/fisiologia , Animais , Hidrocarbonetos/análise , Ecossistema , Solo/química , Fazendas , Agricultura/métodos , Comportamento AnimalRESUMO
This study was carried out to investigate the effects of melatonin applications on postharvest quality changes of organic and conventionally grown plum fruit. Melatonin was applied in 0, 50, and 100 µmol L- 1 for organic and conventional samples. The fruits were stored at + 2.0 °C and 90% relative humidity for 28 days. During the storage period, the color, weight loss, firmness, Soluble solids concentration (SSC), titratable acidity (TA), pH, total antioxidant content, and total phenolics were evaluated at 7-day intervals. While no effect of melatonin applications on weight loss of organically grown plums was observed, it was determined that weight loss decreased as the dose of melatonin increased in conventionally grown plums. The lowest weight loss during storage was determined in conventionally grown plums treated with 100 µmolL- 1 melatonin. It was observed that the firmness values decreased as the storage period increased in both cultivation methods. The firmness decreased as the dose of melatonin application increased in organically grown plums, while the firmness increased as the dose of melatonin application increased in conventional cultivation. Melatonin application did not positively affect SSC, pH, and color values. However, it was determined that the mean TA values decreased as the dose of melatonin increased in both cultivation methods. When the total phenol content of organic and conventional plums was examined, it was determined that melatonin application decreased the number of phenolic compounds. The highest phenolic content was determined in the control samples. The total amount of antioxidants was 1.71 µmol TE g- 1 on the 28th day in the highest (100 µmol L- 1) melatonin-treated conventionally grown plums.
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Armazenamento de Alimentos , Frutas , Melatonina , Prunus domestica , Melatonina/farmacologia , Armazenamento de Alimentos/métodos , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Frutas/química , Prunus domestica/efeitos dos fármacos , Prunus domestica/crescimento & desenvolvimento , Antioxidantes/metabolismo , Fenóis/metabolismo , Agricultura Orgânica/métodosRESUMO
The abundance and diversity of antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) in agricultural landscapes may be important for the spread of antimicrobial resistance (AMR) in the environment. The aim of this study was to apply screening methods for ARB and ARGs to investigate the impact of farming on the prevalence of AMR in a country with low antibiotic usage. We have analyzed samples (n = 644) from soil and wild terrestrial animals and plants (slugs, snails, mice, shrews, earthworms, and red clover) collected over two years in agricultural fields accompanied by nearby control areas with low human activity. All samples were investigated for the occurrence of 35 different ARGs using high-throughput quantitative PCR (HT-qPCR) on a newly developed DNA array. In addition, samples from the first year (n = 415) were investigated with a culture-based approach combined with whole-genome sequencing (WGS) to identify antimicrobial-resistant E. coli (AREC). ARGs were detected in 59.5% of all samples (2019 + 2020). AREC, which was only investigated in the 2019 samples, was identified in 1.9% of these. Samples collected in the autumn showed more ARGs and AREC than spring samples, and this was more pronounced for organic fields than for conventional fields. Control areas with low human activity showed lower levels of ARGs and a lack of AREC. The use of livestock manure was correlated with a higher level of ARG load than other farming practices. None of the soil samples contained antibiotics, and no association was found between AMR and the levels of metals or pesticides. High qualitative similarity between HT-qPCR and WGS, together with the positive controls to the validation of our 35 ARG assays, show that the microfluid DNA array may be an efficient screening tool on environmental samples. In conclusion, even in a country with a very low consumption of antimicrobials by production animals, our results support the hypothesis of these animals being a source of AREC and ARGs in agricultural environments, primarily through the use of manure.
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According to their nutritional value, their ability to adapt to the various environmental conditions, and their versatility, cereals are among the most cultivated plants in the world. However, the ongoing climate changes subject crops to important environmental stress that for some varieties leads to high production losses. Therefore, the selection of species and varieties that are more versatile and adaptable to different environmental conditions can be important. However, the characteristics of some cereals are not completely known; this is a priority before aiming to improve their cultivation. The aim of this study is to characterize select species that are potentially suitable for local environmental conditions and that possess nutritional value. The elemental composition was assessed in different cereal species grown following intensive and organic agriculture practices. Six species were grown for this study with techniques of intensive agriculture: Triticum monococcum L., Triticum dicoccum L., Triticum aestivum L., variety Verna, Triticum durum Desf., variety Senatore Cappelli, Triticum durum Desf., variety Claudio, and Avena strigosa Schreb.; four of these were also grown following organic procedures: Triticum monococcum L., Triticum dicoccum L., Triticum aestivum L., variety Verna, and Triticum durum Desf., variety Senatore Cappelli. The study considered twenty elements, including major nutrients (Ca, K, Mg, P, and S), seven micronutrients (B, Cu, Fe, Mn, Mo, Se, and Zn), and trace elements with toxic properties (Al, Ba, Cd, Cr, Na, Rb, Sc, and Sr) that can be accumulated at the seed level. The results highlight the differences in the element concentrations in the cereal seeds in relation to the genus and species; the highest concentrations of the major nutrients appeared in T. monococcum; the concentrations were 6.9, 2.09, 7.2, and 2.9 mg/g for K, Mg, P, and S, respectively. The highest concentrations of certain micronutrients, B, Ca, Mo, and Se (16, 785, 3.69, and 0.34 µg/g), were in A. strigosa. There is also evidence that the element content can be affected by the adopted cultivation procedure; however, the effects of the growing procedure can be significantly different when different species are considered. T. monococcum, grown by an organic procedure, presented lower concentrations of the major nutrients, while it demonstrated a modest increase in the micronutrients in the T. durum variety organic S. Cappelli, and the production procedure did not affect the elemental composition of the T. aestivum variety Verna. The survey also highlights that the studied species and the growing procedure affected the capacity to accumulate and translocate trace hazardous elements for human health at the seed level.
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Grão Comestível , Triticum , Grão Comestível/química , Triticum/química , Agricultura Orgânica , Valor Nutritivo , Oligoelementos/análise , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimentoRESUMO
The article presents information reflecting current consideration of strategy of food production from position of of economic sustainability, ensuring population health through compliance of principles of food safety, accessibility and quality improvement. The organic food industry with systems of production, processing, distribution and retailing develops since the 1940s and has huge impact on strategies of food consumption by population, especially in high-income countries. The priorities, goals and objectives of development of organic production in the Russian Federation are targeted to ensure favorable state of environment and preservation of human health.
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Saúde da População , Humanos , Federação Russa , Alimentos Orgânicos/economia , Inocuidade dos Alimentos , Abastecimento de Alimentos/economiaRESUMO
Soil degradation has been accelerated by the use of chemical pesticides and poor agricultural practices, which has had an impact on crop productivity. Recently, there has been a lot of interest in the use of eco-friendly biochar applications to enhance soil quality and sequester carbon in sustainable agriculture. This study aimed to determine the individual and combined effects of Leaf Waste Biochar (LWB) and the bio-control agent Trichoderma harzianum (BCA) on the development of bacterial wilt in eggplants (Solanum melongena) caused by Ralstonia solanacearum (RS). The effects of LWB and BCA on eggplant physiology and defense-related biochemistry were comprehensively examined. Inoculated (+RS) and un-inoculated (-RS) eggplants were grown in potting mixtures containing 3% and 6% (v/v) LWB, both with and without BCA. The percentage disease index was considerably reduced (90%) in plants grown in the 6% LWB+ BCA amended treatments. Moreover, the plants grown in LWB and inoculated with BCA had higher phenolics, flavonoids and peroxidase contents compared to the non-amended control. The level of NPK was significantly increased (92.74% N, 76.47% P, 53.73% K) in the eggplants cultivated in the 6% LWB + BCA composition. This study has shown that the association of T. harzianum with biochar improved plant growth and reduced R. solanacearum induced wilt. Furthermore, the combined impact of biochar and T. harzianum was greater in terms of wilt suppression and increase in plant physiological measurements when the biochar concentration was 6%. Biochar and bio-control agents triggered biochemical alterations, thus enhancing the management of disease-infested soils.
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Traditional Chinese herbal medicines not only cure human diseases, but also play an important role as insecticides. Compared with conventional chemical agents, traditional Chinese herbal medicines are characterized by low toxicity, low residues, and being eco-friendly, and they have become a research hotspot. Traditional Chinese herbal medicines have tremendous flexibility and indefinite potential. Therefore, this paper reviewed the types of insecticides belonging to traditional Chinese herbal medicines in Inner Mongolia, China, including their traditional uses, secondary metabolites, biological activities, action mechanisms, application methods, and development status. In addition, the most relevant issues involved in the development of traditional Chinese herbal medicines was discussed. We believe that traditional Chinese herbal medicines can be better implemented and developed; such that its other advantages, such as an insect repellent, can be promoted. Moreover, this study lays a solid foundation for further research on traditional Chinese herbal medicines in Inner Mongolia, China.
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Sustainable farming on ever-shrinking agricultural land and declining water resources for the growing human population is one of the greatest environmental and food security challenges of the 21st century. Conventional, age-old organic farming practices alone, and foods based on costly cellular agriculture, do not have the potential to be upscaled to meet the food supply challenges for feeding large populations. Additionally, agricultural practices relying on chemical inputs have a well-documented detrimental impact on human health and the environment. As the available farming methods have reached their productivity limits, new approaches to agriculture, combining friendly, age-old farming practices with modern technologies that exclude chemical interventions, are necessary to address the food production challenges. Growing genetically modified (GM) crops without chemical inputs can allow agricultural intensification with reduced adverse health and environmental impacts. Additionally, integrating high-value pleiotropic genes in their genetic improvement coupled with the use of modern agricultural technologies, like robotics and artificial intelligence (AI), will further improve productivity. Such 'organic-GM' crops will offer consumers healthy, agrochemical-free GM produce. We believe these agricultural practices will lead to the beginning of a potentially new chemical-free GM agricultural revolution in the era of Agriculture 4.0 and help meet the targets of the United Nations Sustainable Development Goals (SDGs). Furthermore, given the advancement in the genome editing (GE) toolbox, we ought to develop a new category of 'trait-reversible GM crops' to avert the fears of those who believe in ecological damage by GM crops. Thus, in this article, we advocate farming with no or minimal chemical use by combining chemical-free organic farming with the existing biofortified and multiple stress tolerant GM crops, while focusing on the development of novel 'biofertilizer-responsive GE crops' and 'trait-reversible GE crops' for the future.
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Produtos Agrícolas , Edição de Genes , Plantas Geneticamente Modificadas , Desenvolvimento Sustentável , Nações Unidas , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Edição de Genes/métodos , Humanos , Agricultura/métodosRESUMO
Livestock and dairy farmers are increasingly required to maintain productivity and profitability while mitigating the environmental harm associated with high-input agriculture. Accordingly, to reduce reliance on synthetic fertilizers, a wide range of organically derived products are being evaluated for their effects on sward growth and forage quality. This study used glasshouse experiments to investigate the responses of four grass species to a novel organic fertilizer derived from the mass production of black soldier fly larvae [Hermetia illucens, HexaFrass™, Meath, Ireland]. Although there was some variability among trials, overall our results indicate that application of HexaFrass produced increased shoot growth of Perennial Ryegrass (PRG; Lolium perenne L.), Timothy (Phleum pratense L.), and Cocksfoot (Dactylis glomerata L.) compared with growth achieved in no-fertilizer control plants. In addition to increases in shoot fresh and dry weight, shoot chlorophyll content was also positively related to the HexaFrass application rate. At nitrogen-equivalent application rates, HexaFrass resulted in lower shoot growth compared with the application of urea, suggesting that the nitrogen contained in HexaFrass may not be immediately plant-available. Of relevance to grazing or silage systems, the addition of HexaFrass resulted in increased shoot regrowth of PRG and Timothy after shoots had been cut. Based on our results, insect-frass-based fertilizers may have a role in low input, organic, and/or regenerative pasture-based livestock systems, although issues may occur due to the relatively high costs and low availability compared with other organic soil amendments such as farmyard manure and slurry.
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Seedcorn maggot, Delia platura (Meigen) (Diptera: Anthomyiidae), is an economically important early-season pest of corn and soybean in the United States. Adult seedcorn maggot is attracted to decomposing plant residues for oviposition, creating potential management issues where growers typically use tillage to incorporate fertility amendments and to create a seedbed. The use of growing degree-day models to time planting dates is an important tool for effectively managing this pest, but their use has not been examined in organic crop production. Here, we report the results of experiments to determine the effects of cover crops, tillage, and relative planting date on seedcorn maggot in corn and soybean in 2 experiments: The first during the transition to organic from conventional management and the second during the 3 yr following organic certification in central Pennsylvania, United States. Overall, delaying the planting date by 1-2 wk reduced fly emergence in corn, but not in soybean in both experiments. Seedcorn maggot emergence was also consistently greater in corn than in soybean, with 6 times more flies in corn than in soy. About 15 times more seedcorn maggot flies emerged from corn in treatments in which cover crops were managed with tillage compared to treatments in which cover crops were terminated with a roller-crimper followed by no-till planting of corn. Fly emergence was negatively related to the proportion of legumes in the cover crop mixture preceding corn. These results can help inform soil, cover crop, and crop decisions for organic growers in the Mid-Atlantic United States.
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Produtos Agrícolas , Dípteros , Feminino , Animais , Larva , Solo , Zea mays , Glycine max , AgriculturaRESUMO
Rhizoctonia solani Kühn (teleomorph: Thanatephorus cucumeris [Frank] Donk) is an aggressive soilborne pathogen with a wide host range that survives saprophytically between crops, presenting a challenge for organic vegetable farmers who lack effective management tools. A 2-year field experiment was conducted at two organic farms to compare anaerobic soil disinfestation (ASD) and worm-cured compost (vermicompost) to manage bottom rot caused by R. solani subspecies AG1-IB in field-grown organic lettuce (Lactuca sativa). At each farm, four replicate plots of seven treatments were arranged in a randomized complete block design. Randomization was restricted by grouping treatments to evaluate ASD, and treatments to evaluate vermicompost in starter plugs. ASD experiment treatments were three different ASD carbon sources that are commonly used and widely available to local farmers in Vermont: compost, cover crop residues, and poultry manure fertilizer, as well as a tarped control. Vermicompost experimental treatments were vermicompost compared with two types of controls: a commercial biocontrol product (RootShield PLUS + G), and unamended (untarped control). This study demonstrated that the ASD method is achievable in a field setting on Vermont farms. However, neither ASD nor vermicompost produced significant disease suppression or resulted in higher marketable yields than standard growing practices. Given the laborious nature of ASD, it is likely more appropriate in a greenhouse setting with high-value crops that could especially benefit from being grown in plastic tarped beds (e.g., tomatoes and strawberries). This study is the first known attempt of field-implemented ASD for soil pathogen control in the northeastern United States.
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Compostagem , Lactuca , Doenças das Plantas , Rhizoctonia , Solo , Lactuca/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Compostagem/métodos , Solo/química , Rhizoctonia/fisiologia , Microbiologia do Solo , Anaerobiose , Agricultura Orgânica/métodosRESUMO
Biopesticide fungicides are naturally derived compounds that offer protection from plant diseases through various modes of action, including antimicrobial activity and upregulation of defense responses in host plants. These plant protectants provide a sustainable and safe alternative to conventional pesticides in integrated disease management programs and are especially salient in the management of high-risk and economically important diseases such as late blight of tomato and potato, for which host resistance options are limited. In this study, a commercially available biopesticide, EF400 comprised of clove (8.2%), rosemary (8.1%), and peppermint oils (6.7%) (Anjon AG, Corcoran, CA), was investigated for its effects on the Phytophthora infestans-tomato pathosystem. Specifically, we evaluated the impact of EF400 on P. infestans growth in culture, disease symptoms in planta, and activation of host defenses through monitoring transcript accumulation of defense-related genes. The application timing and use rate of EF400 were further investigated for managing tomato late blight. EF400 delayed the onset of tomato late blight symptoms, although not as effectively as the copper hydroxide fungicide Champ WG (Nufarm Americas Inc., Alsip, IL). Pathogen mycelial growth and sporangial quantity on late blight-susceptible tomato leaves were significantly reduced with EF400. The biopesticide also had an enhancing or suppressing effect on the transcript accumulation of three defense-related genes: Pin2, PR1a, and PR1b. Our work in exploring a commercially available horticultural oil biopesticide meaningfully contributed to the essential knowledge base for optimizing recommendations for the management of tomato late blight.
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Phytophthora infestans , Doenças das Plantas , Óleos de Plantas , Solanum lycopersicum , Solanum lycopersicum/microbiologia , Phytophthora infestans/efeitos dos fármacos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Óleos de Plantas/farmacologia , Fungicidas Industriais/farmacologia , Agentes de Controle Biológico/farmacologia , Mentha piperita/química , Interações Hospedeiro-Patógeno/efeitos dos fármacosRESUMO
Organic agriculture is a farming method that provides healthy food and is friendly to the environment, and it is developing rapidly worldwide. This study compared microbial communities in organic farming (Or) paddy fields to those in nonorganic farming (Nr) paddy fields based on 16S rDNA sequencing and analysis. The predominant microorganisms in both soils were Proteobacteria, Chloroflexi, Acidobacteria, Actinobacteria, and Nitrospirota. The alpha diversity of the paddy soil microbial communities was not different between the nonorganic and organic farming systems. The beta diversity of nonmetric multidimensional scaling (NMDS) revealed that the two groups were significantly separated. Distance-based redundancy analysis (db-RDA) suggested that soil pH and electrical conductivity (EC) had a positive relationship with the microbes in organic paddy soils. There were 23 amplicon sequence variants (ASVs) that showed differential abundance. Among them, g_B1-7BS (Proteobacteria), s_Sulfuricaulis limicola (Proteobacteria), g_GAL15 (p_GAL15), c_Thermodesulfovibrionia (Nitrospirota), two of f_Anaerolineaceae (Chloroflexi), and two of g_S085 (Chloroflexi) showed that they were more abundant in organic soils, whereas g_11-24 (Acidobacteriota), g__Subgroup_7 (Acidobacteriota), and g_Bacillus (Firmicutes) showed differential abundance in nonorganic paddy soils. Functional prediction of microbial communities in paddy soils showed that functions related to carbohydrate metabolism could be the major metabolic activities. Our work indicates that organic farming differs from nonorganic farming in terms of microbial composition in paddy soils and provides specific microbes that might be helpful for understanding soil fertility.
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Actinobacteria , Microbiota , Oryza , Solo/química , Microbiologia do Solo , RNA Ribossômico 16S/genética , Agricultura/métodos , Bactérias/genética , Actinobacteria/genética , Oryza/genéticaRESUMO
Crop domestication has led to the development of distinct trait syndromes, a series of constrained plant trait trade-offs to maximize yield in high-input agricultural environments, and potentially constrained trait plasticity. Yet, with the ongoing transition to organic and diversified agroecosystems, which create more heterogeneous nutrient availability, this constrained plasticity, especially in root functional traits, may be undesirable for nutrient acquisition. Such agricultural systems require a nuanced understanding of the soil-crop continuum under organic amendments and with intercropping, and the role crop genetic resources play in governing nutrient management and design. In this study, we use a functional traits lens to determine if crops with a range of domestication histories express different functional trait plasticity and how this expression changes with soil amendments and intercropping. We utilize a common garden experiment including five wheat (Triticum aestivum) varietals with a range of domestication histories planted in a factorial combination with amendment type (organic and inorganic) and cropping design (monoculture or intercropped with soybean). We use bivariate, multivariate and trait space analyses to quantify trait variation and plasticity in five leaf and five root functional traits. Almost all leaf and root traits varied among varieties. Yet, amendment type was nearly inconsequential for explaining trait expression across varieties. However, intercropping was linked to significant differences in root acquisitive strategies, regardless of the varietals' distinct history. Our findings show substantial leaf and root trait plasticity, with roots expressing greater trait space occupation with domestication, but also the strong role of management in crop trait expression. We underscore the utility of a functional trait-based approach to understand plant-soil dynamics with organic amendments, as well as the role of crop genetic histories in the successful transition to low-input and diversified agroecosystems.
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We tested the novel cross of the old local breed Deutsches Lachshuhn and the layer breed White Rock, as well as purebred Deutsches Lachshuhn, for their suitability as dual-purpose chickens under 100% organic husbandry conditions, and compared their performance and welfare with the two dual-purpose crosses New Hampshire × Bresse and Bresse × White Rock, which are already established in Germany. Chicks were reared in mixed-sex groups until slaughter of the males at 15 or 18 weeks of life. Data on laying performance and animal welfare were recorded until the hens' 72nd week of life. Laying performance of Deutsches Lachshuhn × White Rock was almost twice as high as that in purebred hens, while fattening performance of the males did not differ. Deutsches Lachshuhn × White Rock, New Hampshire × Bresse and Bresse × White Rock realized a balanced performance profile of 242-250 eggs per hen alive and a final live weight of the males of 2924-3105 g after 18 weeks of rearing. The efficiency of a pair of chickens (one male and one female) was very similar for the crosses (3.69-3.77 kg feed kg-1 marketable product), while purebred Deutsches Lachshuhn was less efficient (6.35 kg feed kg-1 marketable product). Crossing the breed Deutsches Lachshuhn with a layer breed therefore improved laying performance and overall efficiency of the birds compared to purebred Deutsches Lachshuhn.
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Organic agriculture is of great socioeconomic significance because it can promote the nutritional quality of horticultural crops and is environmentally friendly. However, owing to the lack of techniques for studying complex aroma-related chemical profiles, limited information is available on the influence of organic practices on the flavor quality of strawberries, one of the primary factors driving consumer preferences. Here, two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GC×GC-TOF-MS) and flavoromics analysis was employed to investigate the profiles and differences in the volatile organic compounds (VOCs) of strawberries under organic (without imidacloprid) and conventional (with imidacloprid) agricultural practices. A total of 1164 VOCs, representing 23 chemical classes (e.g., aldehydes, terpenes, and furanone compounds), were detected, which is the highest number of VOCs that have ever been detected in strawberries. The sensory evaluation results indicated that there was a notable influence of imidacloprid (IMI) on the aroma of the strawberries. Principal component analysis and partial least squares discriminant analysis results suggested that the composition of volatile compounds significantly differed in the present study between the IMI-treated and non-IMI-treated groups. Furthermore, the flavor-related indicators of 25 key contributors to the differences between the two treatment groups suggested that VOC profiles can be considered an indicator for distinguishing between strawberries from different agricultural practices. Flavoromics can provide new insights into the quality of strawberries from different agricultural practices.
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Potassium humate is a widely used biostimulant known for its ability to enhance growth and improve tolerance to abiotic stress. However, the molecular mechanisms explaining its effects remain poorly understood. In this study, we investigated the mechanism of action of potassium humate using the model plant Arabidopsis thaliana. We demonstrated that a formulation of potassium humate effectively increased the fresh weight accumulation of Arabidopsis plants under normal conditions, salt stress (sodium or lithium chloride), and particularly under osmotic stress (mannitol). Interestingly, plants treated with potassium humate exhibited a reduced antioxidant response and lower proline accumulation, while maintaining photosynthetic activity under stress conditions. The observed sodium and osmotic tolerance induced by humate was not accompanied by increased potassium accumulation. Additionally, metabolomic analysis revealed that potassium humate increased maltose levels under control conditions but decreased levels of fructose. However, under stress, both maltose and glucose levels decreased, suggesting changes in starch utilization and an increase in glycolysis. Starch concentration measurements in leaves showed that plants treated with potassium humate accumulated less starch under control conditions, while under stress, they accumulated starch to levels similar to or higher than control plants. Taken together, our findings suggest that the molecular mechanism underlying the abiotic stress tolerance conferred by potassium humate involves its ability to alter starch content under normal growth conditions and under salt or osmotic stress.
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Arabidopsis , Arabidopsis/genética , Potássio/metabolismo , Amido , Maltose/farmacologia , Estresse Fisiológico , Sódio/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Organic farming in extensive production regions, such as the Canadian prairies have a particularly difficult challenge of replenishing soil reserves of phosphorus (P). Organic grains are exported off the farm while resupply of lost P is difficult due to limited availability of animal manures and low solubility of rock organic fertilizers. As a result, many organic farms on the prairies are deficient in plant-available P, leading to productivity breakdown. A portion of the solution may involve crop genetic improvement. A hypothetical 'catch and release' wheat ideotype for organic production systems is proposed to (i) enhance P uptake and use efficiency but (ii) translocate less P from the vegetative biomass into the grain. Root traits that would improve P uptake efficiency from less-available P pools under organic production are explored. The need to understand and classify 'phosphorus use efficiency' using appropriate indices for organic production is considered, as well as the appropriate efficiency indices for use if genetically selecting for the proposed ideotype. The implications for low seed P and high vegetative P are considered from a crop physiology, environmental, and human nutrition standpoint; considerations that are imperative for future feasibility of the ideotype.
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The abrupt variation in climatic patterns has become a global concern in terms of food security. Biochar, known to ameliorate climatic adversities by sequestering carbon and activating systemic resistance pathways in plants, has become increasingly relevant. Therefore, the study was aimed to characterize leaf waste biochar (LWB) by Fourier-transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray (SEM-EDX) and X-ray diffraction analytical techniques as well as determination of its impact on the development of bacterial wilt (BW) in eggplant (Solanum melongena) caused by Ralstonia solanacearum (RS). The effect of LWB on the physiology and defence-associated biochemistry of eggplants was investigated thoroughly. Eggplants either inoculated (+RS) or uninoculated (-RS) were cultivated in potting mixture containing 3 and 6% (v/v) LWB separately. In comparison with substrate (soil only), percentage disease index was significantly reduced (71%) in plants grown in 6% LWB-amended treatments. Biochar-induced increase in level of total chlorophyll content as well as in biochemicals such as phenolics, flavonoids and peroxidases were evident on plants in terms of resistance response against BW. Moreover, biochar also significantly affected the level of NPK in the eggplants. In conclusion, biochar-triggered biochemical alterations played a pivotal role in the management of BW along with the curing of the disease-infested soils.
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Background: Transforming food systems is necessary to address the global issues of severe biodiversity loss, hunger, and malnutrition as well as the consequences of the rapidly advancing climate change. Agroecology as a systemic approach has been recognised as a promising path of change exemplified in various case studies strengthening this transformation. The aim of this study is to get insight specifically for Austria and Germany in providing an overview of the advancement in agroecology in both countries and identify agroecology-related initiatives. Methods: 21 interviews with experts were conducted to determine the recognition, understanding, and development of agroecology in Austria and Germany in terms of movement, practice, policies, education, and research. In addition, information about agroecology-related initiatives was collected from interviews with 24 representatives of initiatives and literature analysis. Data was analysed according to five activity categories under which agroecology manifest: movement, practice, living lab, science and research infrastructure, and training and education. Results: Results show that the term agroecology is not commonly used in Austria and Germany, where the concept is mainly associated to a scientific discipline. Practices considered agroecological are implemented primarily through organic agriculture, which is very developed in Austria and to a lesser extent in Germany. Many networks, food policy councils, associations, and scientific projects related to agroecology exist, each with specific purposes and ambitions to change farming and food systems. While most selected initiatives do not explicitly refer to agroecology, all follow certain agroecological principles and aim at contributing to accelerate the agroecological transition. Conclusions: Clarifying the concept of agroecology, overcoming economic and political barriers as well as fostering participation of a multitude of stakeholders in the transition is essential for the future development of agroecology in Austria and Germany.