Chemical and Biological Technologies in Agriculture最新文献

Nickel (Ni) pollution in soil is a major environmental challenge to global food security necessitating its effective remediation. In this regard using plant growth promoting rhizobacteria (PGPR) and bioorganic fertilizers (BOF) to increase the effectiveness of Ni phytoextraction together with hyper-accumulator plants is an effective strategy. Thus, the aim of this study was to assess how BOF, alone or in combination with Bacillus sp. MN54 (herein after referred to as BS), promotes the growth and detoxifies Ni in Brassica juncea L. under both non-contaminated and Ni-contaminated soil conditions. The experimental design included both non-spiked and Ni-spiked soils (with two Ni concentrations: 50 and 100 mg kg⁻¹), with the addition of BS and BOF at two different application rates (1% and 2%). Results showed that Ni negatively affected the growth attributes and yield of Brassica juncea but the integrated incorporation of BOF and BS significantly improved plant growth and physiological attributes. However, Ni stress increased antioxidant enzyme activities and triggered the production of reactive oxygen species in the plants. Likewise, the highest increases in Ni bioconcentration factor (19.9%, 72.83%, and 74.2%), Ni bioaccumulation concentration (30.6%, 327.4%, and 366.8%), and Ni translocation factor (22.2%, 82%, and 69%) were observed in soils supplemented with 2% BOF and BS under non-contaminated, 50 mg kg⁻¹, and 100 mg kg⁻¹ Ni-stressed conditions, respectively. The enhanced plant growth with BS and BOF under Ni stress suggested that both could efficiently promote Ni phytoextraction and simultaneously improve soil health in Ni-contaminated soil. This highlighted their potential as sustainable soil amendments for remediating Ni-contaminated soils, promoting resilient plant growth and supporting long-term ecosystem recovery.

Background

Root rot, wilt diseases, and rooting processes have been the major factors that constrain schefflera production. This study focuses on the impact of innovative applications of eco-friendly materials like chitosan nanoparticles loaded with l-proline or indole butyric acid to replace traditional chemical fungicides in controlling root rot and wilt diseases, as well as the vegetative propagation success of leafy stem schefflera cuttings.

Results

Fusarium foeten (strain 1) and Fusarium falciforme (strains 2 and 4) were first identified as root rot and wilt pathogens of schefflera in Egypt based on morphological features and confirmed with molecular analyses. Fusarium foetens (strain 1) and F. falciforme (strain 2) have the most aggressive action, as the infection percentages significantly increased in the pathogenicity test. The disease incidence reached 38.88 and 44.44%, respectively, whereas the disease severity was 18.51 and 26.84%, respectively. Chitosan nanoparticles at a concentration of 25 mg/L were the most effective dose, leading to a significant reduction in disease incidence to 25.00%, disease severity to 4.17%, and playing a vital role in activating plant defense, which correlates well with improved growth characteristics. The novel strategy of L-proline loaded on chitosan nanoparticles (LP-CSNPs) application occupied the first rank at protective influence against root rot and wilt disease-induced oxidative stress, signaling a defensive function that was freelance verified. L-proline loaded on chitosan nanoparticles (LP-CSNPs) at 0.125–0.25 g/L had a significant impact on reducing the incidence and severity of root rot and wilt diseases, as well as improving photosynthetic pigments and free radical scavenging activities, which included strengthening plant defense and further validating the findings from the biochemical trait analysis. The TT biplot graph was an influential statistical tool to study the impacts of treatments on schefflera production and its attributes and to discover the interrelationships among them.

Conclusions

Applying LP-CSNPs is one of the best techniques to manage schefflera root rot and wilt diseases, since it can be utilized as a growth stimulator and defense activator with sustainable increased efficiency.

Graphical Abstract

Background

Phosphine (PH₃) resistance in stored grain insect pests poses a significant challenge to effective pest control strategies worldwide. This study delved into understanding PH₃-resistant mechanism, with the objective of informing robust and sustainable pest management strategies that could mitigate the impacts of PH₃ resistance.

Results

In this regard, the transcriptomic analysis identified 23 genes associated with chitin synthesis and cuticle formation, which showed significant expression in PH₃-resistant (R) strains compared to susceptible strains. Micro-computed tomography (Micro-CT) revealed an extended and tighter cuticular structure in the PH₃-R Tribolium castaneum than PH₃-susceptible strains but with no changes in the cuticle thickness. This altered cuticle structure may reduce PH₃ penetration through cuticles rather than completely closing spiracles during fumigation. It is also hypothesized to prevent water loss from the insect body, as water production decreased in PH₃-R T. castaneum due to the down-regulation of the electron transport chain function. Validation of several chitin synthesis gene expression levels revealed consistent results with those of transcriptomic analysis.

Conclusion

Overall, integrating physical treatments using synthetic amorphous silicates, water absorbents, and cuticle-damaging materials during PH₃ fumigation is recommended for its prolonged and controlled usage in the field.

Graphical abstract

Background

Over the past decade, researchers have been exploring the potential therapeutic benefits of volatile oils (VOs) in addressing various disorders, particularly those associated with an increase in fungal infections. This study aimed to analyze the chemical compositions of three different thyme species growing in Palestine using gas chromatography–mass spectroscopy (GC–MS) and explore their antifungal characteristics. The thyme species investigated in this research encompass Origanum syriacum L., Clinopodium serpyllifolium subsp. fruticosum (L.) Bräuchler, and Thymbra capitata (L.) Cav.

Methods

The VOs of the investigated plants were extracted by hydrodistillation technique equipped with Cleavenger apparatus and characterized by utilizing GC–MS equipment. Moreover, the extracted VOs were evaluated for their antifungal activity using the broth microdilution assay against several clinically isolated Candida species and one ATCC strain.

Results

The GC–MS characterization results of O. syriacum VO revealed the presence of 22 components and the abundant molecules were thymol (37.36%), carvacrol (27.71%), γ-terpinene (17.47%), and p-cymene (7.80%), while 19 compounds were characterized in the C. serpyllifolium VO and the major components were p-cymene (37.58%), carvacrol (22.93%), and γ-terpinene (21.91%). In addition, 23 compounds were identified in T. capitata VO and the main components were carvone (59.45%), pulegone (21.59%), menthone (4.24%), and isomenthone (3.71%). According to the antifungal assay results, VO extracted from O. syriacum has the highest activity among all the screened VOs.

Conclusion

All the VOs screened in this study exhibit promising antifungal activities for various potential medical applications. Consequently, we strongly advocate for further biological investigations of these oils in the near future.

Graphical Abstract

The production of safe and high-quality silage has always been the main concern. This experiment aimed to investigate the impact of waste dried soybean curd residue (SR) and Lactobacillus plantarum CCZZ1 on the fermentation quality and microbial community of total mixed ration (TMR) silage based on Napier grass (Pennisetum purpureum). Napier grass was made into TMR, and SR at 3%, 6% or 9% on dry material basis was included, which replaced the equivalent amount of corn meal, then they were inoculated without or with Lactobacillus plantarum CCZZ1 (10⁵ cfu g⁻¹; LP). The research results showed that incorporating SR even at 3% resulted in significant reduction in ammonia nitrogen content (87.3 g kg⁻¹ total nitrogen vs. 109.7 g kg⁻¹ total nitrogen), increased lactic acid content (34.4 g kg⁻¹ DM vs. 25.5 g kg⁻¹ DM), and higher relative abundance of Lactobacillus (94.5% vs. 32.2%). Additionally, it led to decreased relative abundances of pathogenic microorganisms such as Escherichia coli (< 0.1% vs. 9.68%), Staphylococcus epidermidis (< 0.1% vs. 9.46%), and Streptococcus pneumoniae (< 0.1% vs. 8.53%) during the ensiling process. When SR was used together with LP inoculation, they were further improved. These findings suggest that the inclusion of SR, even at a 3% level without LP inoculation, can effectively improve the fermentation quality and microbial profile of TMR silage based on fresh Napier grass. This offers a promising technical approach to utilizing SR and producing safe and high-quality TMR silage based on fresh grass.

Graphical Abstract

Background

Winter wheat grain samples from 185 sites across southern Shanxi region were processed and analyzed using a non-destructive approach. For this purpose, spectral data and protein content of grain and grain powder were obtained. After combining six types of preprocessed spectra and four types of multivariate statistical models, a relationship between hyperspectral datasets and grain protein is presented.

Results

It was found that the hyperspectral reflectance of winter wheat grain and powder was positively correlated with the protein contents, which provide the possibility for hyperspectral quantitative assessment. The spectral characteristic bands of protein content in winter wheat extracted based on the SPA algorithm were proved to be around 350–430 nm; 851–1154 nm; 1300–1476 nm; and 1990–2050 nm. In powder samples, SG-BPNN had the best monitoring effect, with the accuracy of R_v² = 0.814, RMSE_v = 0.024 g/g, and RPD_v = 2.318. While in case of grain samples, the SG-SVM model exhibited the best monitoring effect, with the accuracy of R_v² = 0.789, RMSE_v = 0.026 g/g, and RPD_v = 2.177.

Conclusions

Based on the experimental findings, we propose that a combination of spectral pretreatment and multivariate statistical modeling is helpful for the non-destructive and rapid estimation of protein content in winter wheat.

Graphical Abstract

Background

Duke cherry is a non-climacteric fruit but deteriorates quickly during storage due to thin pericarp and succulent fruit tissue. The application of edible coatings, essential oils, or their combination is an appropriate technique to maintain the quality characteristics and reduce the deterioration of fruits during storage. This research assessed the effect of Aloe vera gel (AVG), thymol, and their combined use on the physicochemical and qualitative properties of duke cherries kept at 5 °C and 80% relative humidity for 28 d.

Results

Compared to the uncoated fruits, duke cherries coated with a combination of AVG and thymol, showed more values of firmness (12.76–100.32%), total phenol (9.99–45.09%), antioxidant activity (7.90–84.56%), and sensory scores(50.15–100.00%), as well as the activity of guaiacol peroxidase (GPX) (12.03–185.11%) and catalase (CAT) (10.20–243.66%) enzymes during cold storage. Moreover, duke cherries coated with a combination of AVG and thymol had remarkably lower values of weight loss (32.57–42.67%), respiration rate (34.96–49.78%), stem browning (24.50–50.53%), spoilage percentage (84.55–100%), anthocyanin (14.21–23.16%), and total soluble solids/titratable acidity (TSS/TA) (35.64–50.15%), as well as hydrogen peroxide (H₂O₂) (16.66–32.35%) and malondialdehyde (MDA) (15.23–31.05%).

Conclusion

The application of AVG and thymol, particularly their combination, can have a high practical potential to extend shelf-life and preserve the quality of duke cherries during cold storage. This treatment has various advantages including natural, edible, cost-effective, and efficient.

Graphical Abstract

Background

Guayulins comprise a family of sesquiterpene compounds with potential industrial applications that are extracted from the resinous fraction of the guayule plant (Parthenium argentatum, A. Gray). If a whole industry is to be developed around guayulins, not only their activity should be assessed, but also their stability because the quality of the final products is likely influenced by the time that elapses from harvesting to processing. Thus, the aim of the present study was to evaluate the stability of guayulin compounds from harvested guayule stems or extracted resin after storage at different temperatures to find in which form, stems or resin, is the storage better.

Results

Results showed that, once extracted, the resin could be stored at 20-25 °C for 3 months or more without significant losses of guayulin content. In the case of harvested stems, however, the findings were more complex, with guayulins A and B degrading over time and guayulins C and D showing enrichment. In addition, analysis of the thermal and thermo-oxidative degradation of the resin and guayulins showed that while guayulins A and B showed a maximum decomposition rate around 280 °C, guayulins C and D decomposed at 245 °C. Such thermal differences might be attributed to the observed oxidation of guayulin A and B standards into guayulin C and D, respectively.

Conclusion

These findings provide, for the first time, information on the stability of guayulins after harvesting and resin extraction, which could help to the development of an integral industrial process from harvesting to commercializing.

Graphical Abstract

Background

Research interest in plant essential oils has increased significantly due to their natural properties and consumer demand for safer methods of food preservation. Plants produce large amounts of secondary metabolites, which have potential activity against fungal pathogens. This study aimed at screening essential oils for their antifungal effects on citrus against Penicillium digitatum, morphological effect and finally determine which essential oils are the most effective.

Results

The EC₅₀ of seven selected cinnamon (0.424 μL/mL), patchouli (0.513 μL/mL), vetiver (0.612 μL/mL), dill (1.597 μL/mL), origanum (1.971 μL/mL) and ylang (2.214 μL/mL) was determined. In addition, cinnamon substantially reduced sporulation (100%) followed by patchouli (86.02%), vetiver (82.73%), and chamomile (79.04%), respectively. Our GC–MS result determined variance in concentration of essential oils compound composition. The total compound composition in all seven essential oils > 1% was found to be 3 in cinnamon, 5 in dill, 10 in origanum, 13 in ylang, 11 in patchouli, 9 in chamomile and 16 in vetiver. Addition of essential oils significantly altered fungal morphology by scanning electron cryomicroscopy. Patchouli and origanum showed broken hyphae while there was an indication of severe deformation and collapse of spores in cinnamon and chamomile.

Conclusion

Based on our findings, we report that these essential oils could potentially be applicable in controlling P. digitatum with reduced concern for human health, environmental contamination and possibly replacement of synthetic treatments.

Graphical abstract

Background

Surfactants are added to spray solutions because they significantly improve foliar uptake of active ingredients (AIs) into the leaves. It was intended to investigate whether surfactant solutions forming a dried deposit on Prunus leaf surfaces after they were sprayed, lead to structural and functional changes of the cuticle/atmosphere interface. This could potentially result in irreversibly enhanced leaf surface wetting, which should be of major disadvantage. Enhanced wetting could promote leaching of ions and promote leaf surface colonization with microorganisms.

Results

Prunus laurocerasus leaf surfaces were sprayed with aqueous solutions of non-ionic alcohol ethoxylates, a cationic, an anionic and one large polar surfactant. Directly after spraying and drying of the different surfactant solutions, wetting contact angles of deionized water (without surfactant) were significantly lower (between 6 and 54°) compared to wetting contact angles on untreated leaves (77°). Leaf surface wettability with deionized water was more pronounced with non-ionic alcohol ethoxylates (wetting contact angles ranging between 6 and 22°) compared to the other 3 surfactants (wetting contact angles ranging between 42 and 54°). Wetting contact angles of deionized water on leaf surfaces treated with non-ionic alcohol ethoxylates continuously increased again over time resulting in final wetting contact angles not different from untreated leaf surfaces. The time-dependent recovery of wetting contact angles was dependent on the degree of ethoxylation of the non-ionic alcohol ethoxylates. The wetting contact angle recovery rate was lower the higher the degree of ethoxylation of the alcohol ethoxylates was. With the cationic, anionic and large polar surfactant a recovery of wetting contact angles was not observed. In addition, on fully dehydrated and dead leaves wetting contact angle recovery was not observed for any of the tested surfactants after spraying and drying. Analytical determinations of the amounts of alcohol ethoxylates on the leaf surfaces after spraying and drying showed that amounts of alcohol ethoxylates decreased over time on the surface (24–72 h).

Conclusion

Our results indicate that non-ionic alcohol ethoxylates diffused within hours from the leaf surface into the leaf over time and thus fully disappeared from the leaf surface. This was not the case with the cationic, anionic and the large polar surfactants remaining on the leaf surface.

Graphical Abstract