ACS agricultural science & technology最新文献

Frass, the principal byproduct of Black Soldier Fly (BSF) farming, is increasingly valued as a sustainable organic fertilizer, partly due to its potential to harbor plant growth-promoting microorganisms (PGPM). This study investigated the presence and activity of PGPM in frass obtained from 10 rearing substrates and evaluated the effect of mandatory heat treatment (70 °C, 1 h). Using a rhizosphere-mimicking agar medium, 149 bacterial isolates were recovered and screened for PGPM-specific traits. Six promising isolates, belonging to Serratia, Peribacillus, Acinetobacter, Pseudocitrobacter, Bacillus, and Enterobacter, were further tested in vivo on Arabidopsis thaliana. They displayed variable effects on seed germination, root elongation, and root hair development linked to their phytohormone profiles. Several strains were recovered from both untreated and heat-treated frass, highlighting their thermotolerance. These findings demonstrate that BSF frass harbors PGPM with strong potential for biofertilizer development.

Former food products (FFPs) are increasingly recognized as sustainable feed ingredients. While nutritionally valuable, FFPs may contain cocoa-based confectionery, which is a source of methylxanthines such as theobromine (TB) and caffeine (CF) and can impact animal health. This study quantified TB and CF concentrations in 12 FFPs using HPLC-UV, evaluated FFP inclusion rates in animals' diets against European Union (EU) maximum levels (MLs), and dietary exposure against toxicological thresholds. TB levels ranged from 59.6 to 1147.1 μg/g and CF from 9.3 to 118.1 μg/g. All products, except one, complied with EU MLs when included at 30% in the diet (on a dry basis). Modeled animal dietary exposure (ADE) indicated that, in most proposed species, TB intake was below safety thresholds; however, the maximum exposure scenarios in piglets exceeded reported no-observed adverse effect levels (NOAEL). These findings highlight the need for species-specific and production-stage-specific evaluations and accurate quantification of methylxanthines when formulating diets with FFPs.

Sweetpotato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Brentidae), is one of the most devastating pests of sweetpotatoes in tropical and subtropical regions. Furanoterpenoids are produced when sweetpotato weevils feed on storage roots, making them potentially unmarketable and toxic to livestock and humans. However, accumulation of these furanoterpenoids in uninfested parts of weevil-infested storage roots is poorly characterized. Here we identified ipomeamarone and its precursor, dehydroipomeamarone, in weevil-infested sweetpotato storage roots and confirmed the identities of the compounds by LC-MS, LC-MS/MS, and NMR analysis. Ipomeamarone induction was systemic in the roots, with elevated levels detected in healthy parts of the roots 2-5 cm away from the site of infestation. A clear relationship between the presence of furanoterpenoids in the storage root and the behavior of C. formicarius elegantulus was found. When adults were presented with root slices taken at several distances from the point of infestation, the number of eggs laid increased progressively with distance from the point of infestation, peaking at 7 cm from the site of infestation. Both egg-laying and adult feeding were reduced on isolated root slices treated with pure ipomeamarone, underscoring the potential role of this compound as a deterrent against C. formicarius elegantulus. This study contributes to our understanding of host plant selection and could inform integrated pest management strategies against the sweetpotato weevil.

Liposomes are microscale lipid vesicles used in pharmaceuticals, food products, and most recently, agriculture. Several studies have shown that liposomes can deliver nutrients to plant leaves, often more efficiently than traditional forms. However, the delivery of plant nutrients to soil via liposomes remains understudied. Interactions between liposomes and soil microbes, including metabolism of the lipid carbon (C) and assimilation of liposome-encapsulated nutrients into soil microbial biomass, could alter the availability of nutrients within the soil. We assessed the impact of lecithin liposomes with nitrogen (N) cargo on C and N cycling during a 7-day incubation experiment. We quantified changes in concentrations of carbon dioxide, nitrous oxide, oxygen, and soil inorganic N pools including soil extractable nitrate (NO₃ ^--N) and ammonium (NH₄ ⁺-N). Liposome additions increased microbial respiration and resulted in rapid soil NO₃ ^--N immobilization, suggesting that liposomes may be a tool to immobilize N and reduce agricultural N losses.

The use of synthetic fertilizers is always more economically and environmentally unsustainable. It is necessary to improve current agricultural practices. Bioactivated fertilizers are a promising solution to enhance digestate solid fraction's fertilizing properties with an ad hoc microbial consortium and reach yields comparable to chemical fertilization (CF), thus combining circular economy with an upgraded organic agriculture. This study designed a new granulated formulation, obtained using a vacuum drying process at the industrial level, for an improved Trichoderma-activated digestate's solid fraction. This granulation aimed to improve both management operations and Trichoderma activity. After a greenhouse experimentation, yields obtained from the activated digestate (56 ± 7 g FW plant^-1) were similar to the one obtained with CF (62 ± 9 g FW plant^-1). Additionally, the bioactivated digestate gave yield production that were 21-30% higher yield than that of digestate alone. Microbial activation further led to higher nutritional values with an increment in the lycopene content between 8.8% and 15.8%. A metagenomic analysis further highlighted the persistence of Trichoderma in the tomato rhizosphere and its ability to establish positive interactions with other beneficial rhizospheric microorganisms. Activated digestate showed its potential to substitute CF, while granulation resulted in a functional formulation to convey this product.

This study evaluated three methods, methyl tert-butyl ether-sodium hydroxide (MTBE-NaOH) method, EPA method 1633, and U.S. Food and Drug Administration (FDA) chemical analytical manual (CAM) method C-010.03, for their effectiveness in extracting PFAS from soybean tissues. EPA method 1633 consistently delivered the highest and most reproducible EIS recoveries when plant tissues contained PFAS at low levels. Regarding target PFAS extraction efficiency, EPA method 1633 also demonstrated superior performance at environmentally relevant low concentrations. At higher PFAS concentrations in plant tissues, no single method clearly dominated; however, EPA method 1633 remained consistently reliable and was never significantly outperformed by the other two methods. Overall, EPA method 1633 is recommended as the default method for routine analyses at typical environmental PFAS levels, with MTBE-NaOH method preferred when accurate isotopic correction based on EIS recovery is critical in highly contaminated plant samples. A cost comparison of these three methods further supports the preference for EPA Method 1633 and MTBE-NaOH method for plant-tissue analyses. These findings contribute to PFAS risk assessment in agricultural and food safety contexts by enhancing the understanding of PFAS interactions with edible crops.

The increasing demand for bee-derived products such as honey and bee pollen has led to a rise in adulteration and mislabeling, making it essential to develop reliable tools for authentication. Lipids, which are found in both matrices, are potential biomarkers for tracing their origin and may be used for detecting fraud. In this work, a solid-liquid extraction using hexane:isopropanol (10:1, v/v) followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was optimized. The method was applied for tentative lipid screening of 15 honeys and 13 bee pollens showing a total number of lipids above 700, including fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, and sterol lipids. For the first time, a principal component analysis was carried out for botanical and geographical origin, classifying most of the samples correctly. Additionally, the method was categorized as green (environmentally friendly) and blue (practical).

The elimination of keratin-derived waste, such as pig bristles, represents a significant challenge due to its high production levels and resistance to degradation. However, the keratinous composition also makes pig bristles a valuable waste material with significant potential for bioconversion into biostimulants rich in bioavailable nitrogen, peptides, and amino acids. To achieve degradation, microorganisms with keratinolytic activity isolated from the raw material were selected. Based on the best performance in plant PGP traits, solubility, and protease activity, Sporosarcina luteola was chosen to implement a fermentation technology that converts pig bristle waste. The fermented product comprises three classes of biostimulant components: the biomass of S. luteola, the enzymatic secretions of this microorganism, and the hydrolyzed organic matter from pig bristles, which is rich in protein hydrolysates and free amino acids. The biostimulant was evaluated in soil at the biochemical level (enzymatic activities) and in plants under oxidative stress, demonstrating a positive effect. These findings highlight the fermentation process using S. luteola as a promising strategy for the comprehensive valorization of pig bristle waste, resulting in products with significant agronomic and environmental benefits.

As novel nanopesticides, cupric oxide nanoparticles (CuO NPs) have emerged as a cost-effective, ecofriendly, and sustainable alternative for controlling plant pathogens. However, additional research effort is still needed to elucidate the antibacterial mechanism involved. In this study, bioinspired CuO NPs were synthesized, and their antibiofilm strategies against R. solanacearum were systematically investigated. CuO NPs effectively inhibited the biofilm formation of R. solanacearum at various stages of maturity (24, 48, and 72 h) by damaging the cellular morphology and reducing the extracellular polysaccharide (EPS) and protein content of bacteria within biofilms. The motility activities of R. solanacearum, including swimming, swarming, and twitching, were significantly inhibited upon exposure to CuO NPs. Furthermore, we confirmed that both two-dimensional and three-dimensional structures of mature biofilms (at 24 h) were disrupted, as determined by confocal laser scanning microscopy (CLSM), atomic force microscopy (AFM), and scanning electron microscopy (SEM), revealing a scattered morphology and a disrupted surface topology pattern. Importantly, the quantitative reverse transcription polymerase chain reaction (qRT-PCR) was employed to assess the transcriptional levels of genes related to biofilm formation and virulence in R. solanacearum stems following treatment with CuO NPs. Notably downregulated genes included those involved in chemotaxis (cheA and cheW), EPS-related genes (xpsR and epsE), swimming activity (flgC, fliA), the quorum-sensing (QS) system (solR, phcB, phcS), the type III system (T3SS) (prhI and hrpG), and the two-component system (pehS and pehR). These findings provide insight into the antibiofilm properties of CuO NPs and hold promise regarding their potential as nanoenabled strategies for combating pathogens and sustainable management of crop diseases.