ACS agricultural science & technology最新文献

A precise measurement of soil potassium (K) concentration is crucial for enhancing agricultural productivity and promoting sustainable land management. The efficiency of real-time soil quality monitoring is hampered by the time-consuming laboratory analysis that is commonly associated with conventional methods. The present research introduces an innovative approach utilizing a field-effect transistor (FET) structure coated with reduced graphene oxide-decorated valinomycin (rGO-v) for the detection of potassium ions in soil samples. The sensor exploits the distinctive electrical properties of reduced graphene oxide (rGO) and the specific affinity of valinomycin for potassium ions. To construct the device, we applied rGO-v onto an FET substrate. The conductance of the FET can be modified by the interaction between valinomycin and potassium ions, enabling the detection of potassium ions. Some of the advantages of this technology are its high sensitivity, fast response time, and potential for miniaturization. In addition, the device is tuned to demonstrate an enhanced sensitivity of 0.98 μA/(kg/ha) below the threshold voltage. The sensor exhibits a response time of 40 s and demonstrates exceptional stability in the face of unfavorable conditions, specifically humidity. Therefore, valinomycin-decorated reduced graphene oxide, when subjected to appropriate gate bias, demonstrates promising results as a versatile, cost-effective, and easy-to-use potassium ion sensor.

The present work aimed to obtain chitosan derivatives with greater solubility in water, good physicochemical properties, and potent antifungal activity against plant pathogens. In this study, the modification of chitosan (CS) with vanillic acid (VA) was achieved via free radical grafting by optimizing the VA to CS ratio. The grafted CS (VA-g-CS) samples were characterized, and their antifungal activity toward Fusarium solani and Fusarium proliferatum was evaluated. All VA-g-CS samples demonstrated successful conjugation between CS and VA, with different grafting degrees, altered surface morphology, and improved water solubility. The results indicated that VA-g-CS with a mass ratio of 0.5:1 exhibited the highest content of VA (74.6 ± 1.42 mg of VAE/g) with an amino substitution percentage of 50.3 ± 0.54%. Increasing the concentration of VA-g-CS from 1.0 to 5.0 mg/mL enhanced their antifungal activity. Furthermore, VA-g-CS (0.5:1) at 5.0 mg/mL showed better antifungal activity than other grafted CS, with more than 80 and 76% inhibition against F. solani and F. proliferatum, respectively. The modification of CS with VA offers a new strategy for controlling plant pathogenic fungi.

Mycotoxin contamination of food may lead to cancer and is caused by fungal pathogens. In this study, we discovered that two natural products, phenylacetate and acetophenone, inhibit the growth of mycotoxin-producing fungi of agricultural importance. Using disc diffusion assays, we observed that both chemicals demonstrated antifungal activity against mycotoxin-producing Aspergillus flavus. The efficacies of acetophenone and phenylacetate synergized against A. flavus and four additional mycotoxin-producing fungi such as A. parasiticus, Penicillium expansum, Fusarium oxysporum, and F. verticillioides. Using growth kinetic assay, we observed that phenylacetate and acetophenone inhibited growth rates of human fungal pathogens, Candida albicans and C. auris. High-performance liquid chromatography analysis of aflatoxins extracted from A. flavus demonstrated that acetophenone treatment inhibited the production of aflatoxins, while phenylacetate did not have such an effect. This study identifies the phenylacetate–acetophenone combination as a potential antifungal for the mycotoxin-producing fungal treatment of food.

Effective nitrogen management is of paramount importance for achieving high tomato yields, given its role in promoting growth and biomass production. The use of slow-release fertilizers (SRFs) is crucial for the reduction of nitrogen loss through leaching and volatilization, thereby mitigating the risk of water pollution and eutrophication. The objective of this study is to evaluate the impact of a novel sandy loam soil treated with slow-release fertilizer pellets comprising hydroxyapatite (HAP) and carboxylated cellulose nanocrystal (CNC_CA) composites on tomato growth. Greenhouse pot experiments were conducted using urea (U), HAP-U, HAP-CNC_CA-U, and control treatments under normal irrigation conditions. The slow-release fertilizers resulted in a notable enhancement in plant growth parameters, including height, stem diameter, number of leaves, chlorophyll content, fresh weight, and dry weight, in comparison to the untreated soils (P < 0.05). The HAP-CNC_CA-U treatment demonstrated a 32% increase in fresh biomass and a 26% increase in dry biomass in comparison to the urea treatment. The slow-release results indicated that the nitrogen release was prolonged, with a cumulative nitrogen release of 31% from HAP-CNC_CA-U within 6 days, in comparison to the complete release observed with urea. These findings illustrate the potential of HAP-CNC_CA-U as an effective nitrogen management system for sustainable tomato cultivation.

Although fabrication of various fullerenols as agronanozymes has undergone remarkable expansion through employing various approaches, there is a lack of knowledge regarding the understanding of metallic-ion-free fullerenols. A feasible preparation technology to fabricate metallic-ion-free fullerenols was developed by heating-treatment oversaturated fullerene using H₂O₂ solution in o-dichlorobenzene. It was characterized as C₆₀(OH)₃₆·9H₂O by various measurements. Maize exposure of 50 mg/L C₆₀(OH)₃₆·9H₂O was investigated to significantly enhance growth traits, including seed germination and seedling growth. Additionally, through the integration of ESR spectrum, radical scavenging assay, and peroxidase-like catalytic performance in vitro, DAB staining to visualize the accumulated H₂O₂ content in vivo as well as investigating the activation of antioxidative performance, it offers insights into the combinational action mechanism of C₆₀(OH)₃₆·9H₂O on crop growth regulation. C₆₀(OH)₃₆·9H₂O directly scavenged accumulated H₂O₂ and indirectly activated the antioxidant system to suppress the H₂O₂ accumulation that acts like peroxidase activity. The present study gives an updated knowledge on synthesizing metallic-ion-free fullerenols with particular emphasis to their application as potential peroxidase-like nanozymes for regulatory roles in the improvement of crop growth.

Our research focused on developing a highly sensitive whole-spore real-time immuno-PCR (RT-iPCR) assay for the detection of three wheat fungal pathogens: Pyrenophora tritici-repentis (Ptr), Fusarium graminearum (Fg), and Puccinia striiformis forma specialis (f. sp.) tritici (Pst). RT-iPCR measurements were compared to more well-established quantitative PCR (qPCR) assays to compare their performance. While specificity remained a challenge for RT-iPCR, the direct spore measurements negate the need for DNA extraction, making RT-iPCR a potentially valuable technique that warrants further research. An alternative approach was developed to determine DNA extraction efficiency and quantification of spore numbers by qPCR, which is currently a methodological gap in most qPCR spore measurements. DNA extraction efficiency determined for Fg, Pst, and Ptr spores were 5.0 ± 0.1, 7.0 ± 0.4, and 290 ± 36%, respectively, demonstrating important implications for the accuracy of these techniques when DNA recovery is not considered.

In the past decade, many studies have investigated the effects of biostimulants on viticulture. However, the impact of pyroligneous acid (PA) on grape (Vitis vinifera) production has not yet been reported. In this study, PA at varying concentrations (0, 4, 8, and 12% PA) and application frequencies (14-, 21-, and 28-day intervals) were applied to enhance the growth, yield, and quality of grapes (cv. KWAD7-1). The results showed that the treated grapes responded differently to PA application. The 4 and 8% PA showed a nonsignificant (p > 0.05) increase in yield of about 0.37- and 0.18-fold, respectively, compared to the 0% PA. The 12% PA, on the other hand, reduced the yield by approximately 0.03-fold compared to the 0% PA. Carotenoid, total phenolics, flavonoid, and sugar were altered by the PA. Interestingly, the 4% PA significantly (p < 0.05) improved total carotenoids (0.34-fold), total phenolics (0.26-fold), and flavonoids (0.26-fold) compared to the 0% PA. The 4% PA applied at 21-day and 28-day intervals remarkably improved vine and leaf growth, respectively. In conclusion, the 21-day interval of PA application significantly (p < 0.05) improved fruit fresh weight, juice weight, juice volume, press weight, °Brix, pH, salinity, total dissolved solids, electrical conductivity, and titratable acidity. Further study is necessary to assess how PA can influence the metabolites present in grape wine.

Fruit flies are naturally attracted to fermenting yeast because yeasts are necessary for Drosophila courtship and egg production and serve as a food source for larval development. Therefore, fermentation-based traps have been used to lure fruit fly pests. Such traps contain sucrose solution as the sole source of carbohydrates for yeast fermentation. However, the volatile organic compounds (VOCs) produced during sucrose fermentation by yeast have yet to be determined. We used SPME-GC/MS analysis and identified VOCs produced by Saccharomyces cerevisiae grown on 50 mM sucrose for 1 h, 1 day, and 4 days. A total of 101 VOCs were identified, representing acids, alcohols, aldehydes, and ketones. The abundance of VOCs varied, with five major VOCs (2-methylbutanol, 3-methylbutanol, ethanol, 2-phenethyl alcohol, and ethyl octanoate) representing 80% of all volatile abundance. The abundance of some VOCs increases over time, whereas others decrease or do not change over time. Future studies will determine specific VOCs that contribute to attracting fruit flies to sucrose-fermenting yeast.

Push–pull technology refers to a promising mixed cropping practice for sustainable agricultural intensification, which uses properties of intercrop and border crop species to defend a focal crop against pests. Currently, the most widely practiced system uses Desmodium spp. as intercrop and Brachiaria or Napier grass as border crops to protect maize (Zea mays) against both insect pests and parasitic weeds. Several previous studies have demonstrated the efficacy of the push–pull system, but research on the underlying chemical mechanisms has mostly been limited to laboratory and glasshouse experiments that may not fully reproduce the complexity of the system under natural conditions. To address this limitation, we performed a large-scale study in farmer-operated push–pull maize fields in three east African countries. We compared maize leaf extracts from plants grown on push–pull fields with maize from fields employing conventional agricultural practices to assess the influence of push–pull cultivation on the maize metabolome. We identified two benzoxazinoid glycosides, which are known to have antiherbivore properties and were present in greater relative abundance in push–pull-cultivated maize leaves across three countries. Our data thus suggest that maize cultivated under push–pull has an increased resistance to herbivore attack compared to maize grown under conventional local agricultural practices.