Plant Protection Strategies Research Articles

Advancements in Bacteriophages for the Fire Blight Pathogen Erwinia amylovora.

Erwinia amylovora, the causative agent of fire blight, causes significant economic losses for farmers worldwide by inflicting severe damage to the production and quality of plants in the Rosaceae family. Historically, fire blight control has primarily relied on the application of copper compounds and antibiotics, such as streptomycin. However, the emergence of antibiotic-resistant strains and growing environmental concerns have highlighted the need for alternative control methods. Recently, there has been a growing interest in adopting bacteriophages (phages) as a biological control strategy. Phages have demonstrated efficacy against the bacterial plant pathogen E. amylovora, including strains that have developed antibiotic resistance. The advantages of phage therapy includes its minimal impact on microbial community equilibrium, the lack of a detrimental impact on plants and beneficial microorganisms, and its capacity to eradicate drug-resistant bacteria. This review addresses recent advances in the isolation and characterization of E. amylovora phages, including their morphology, host range, lysis exertion, genomic characterization, and lysis mechanisms. Furthermore, this review evaluates the environmental tolerance of E. amylovora phages. Despite their potential, E. amylovora phages face certain challenges in practical applications, including stability issues and the risk of lysogenic conversion. This comprehensive review examines the latest developments in the application of phages for controlling fire blight and highlights the potential of E. amylovora phages in plant protection strategies.

Cross-Kingdom RNA Transport Based on Extracellular Vesicles Provides Innovative Tools for Plant Protection.

RNA interference (RNAi) shows great potential in plant defense against pathogens through RNA-mediated sequence-specific gene silencing. Among RNAi-based plant protection strategies, spray-induced gene silencing (SIGS) is considered a more promising approach because it utilizes the transfer of exogenous RNA between plants and microbes to silence target pathogen genes. The application of nanovesicles significantly enhances RNA stability and delivery efficiency, thereby improving the effectiveness of SIGS and further enhancing plant resistance to diseases and pathogens. This review explores the role of RNAi in plant protection, focusing on the cross-kingdom transport of small RNAs (sRNAs) via extracellular vesicles. It also explores the potential of nanotechnology to further optimize RNA-based plant protection, offering innovative tools and methods in modern plant biotechnology.

Repellent Effects of Coconut Fatty Acid Methyl Esters and Their Blends with Bioactive Volatiles on Winged Myzus persicae (Sulzer) Aphids (Hemiptera: Aphididae).

Myzus persicae (Sulzer) (Hemiptera: Aphididae) is one of the most important aphid crop pests, due to its direct damage and its ability to transmit viral diseases in crops. The objective is to test whether spraying nanoemulsions of botanical products repels winged individuals of M. persicae in a bioassay in culture chambers. The bioactive volatiles were applied on pepper plants at a dose of 0.2% alone or at 0.1% of each component in blends. A treated plant and a control plant were placed at each side of an entomological cage inside a growth chamber. The winged individuals were released between the plants, in a black-painted Petri dish suspended by wires in the upper half of the cage. The most repellent products were farnesol (repellency index, RI = 40.24%), (E)-anethole (RI = 30.85%) and coconut fatty acid methyl ester (coconut FAME) (RI = 28.93%), alone or in the following blends: farnesol + (E)-anethole + distilled lemon oil (RI = 36.55%) or (E)-anethole + distilled lemon oil + coconut FAME (RI = 30.63%). The observed effect of coconut FAME on aphids is the first report of this product having a repellent effect on a crop pest. Repellent substances for viral disease vectors should be further investigated to develop new strategies for plant protection.

Viromes of Monocotyledonous Weeds Growing in Crop Fields Reveal Infection by Several Viruses Suggesting Their Virus Reservoir Role.

In 2019, random samples of Panicum miliaceum growing as a weed were surveyed to uncover their virus infections at two locations in Hungary. This pilot study revealed infection with three viruses, two appearing for the first time in the country. As follow-up research, in the summer of 2021, we collected symptomatic leaves of several monocotyledonous plants in the same locations and determined their viromes using small RNA high-throughput sequencing (HTS). As a result, we have identified the presence of wheat streak mosaic virus (WSMV), barley yellow striate mosaic virus (BYSMV), barley virus G (BVG), and two additional viruses, namely Aphis glycines virus 1 (ApGlV1) and Ljubljana dicistrovirus 1 (LDV1), which are described for the first time in Hungary. New hosts of the viruses were identified: Cynodon dactylon is a new host of BYSMV and LDV1, Echinocloa crus-galli is a new host of BVG, ApGlV1 and LDV1, Sorghum halepense is a new host of ApGlV1, and Panicum miliaceum is a new host of LDV1. At the same time, Zea mays is a new host of ApGlV1 and LDV1. Small RNA HTS diagnosed acute infections but failed to detect persistent ones, which could be revealed using RT-PCR. The infection rates at the different locations and plant species were different. The phylogenetic analyses of the sequenced virus variants suggest that the tested monocotyledonous weeds can host different viruses and play a virus reservoir role. Viral spread from the reservoir species relies on the activity of insect vectors, which is why their management requires an active role in plant protection strategies, which need careful planning in the changing environment.

Bio-control of soil-borne virus infection by seed application of Glycyrrhiza glabra extract and the rhamnolipid Rhapynal

Main conclusionSeed-application of the natural products protects sugar beet and wheat plants against infection with plasmodiophorid-transmitted viruses and thus may represent an efficient, environmentally friendly, easy and cost effective biocontrol strategy.In times of intensive agriculture, resource shortening and climate change, alternative, more sustainable and eco-friendly plant protection strategies are required. Here, we tested the potential of the natural plant substances Glycyrrhiza glabra leaf extract (GE) and the rhamnolipid Rhapynal (Rha) applied to seeds to protect against infection of sugar beet and wheat with soil-borne plant viruses. The soil-borne Polymyxa betae- and Polymyxa graminis-transmitted viruses cause extensive crop losses in agriculture and efficient control strategies are missing. We show that GE and Rha both efficiently protect plants against infection with soil-borne viruses in sugar beet and wheat when applied to seeds. Moreover, the antiviral protection effect is independent of the cultivar used. No protection against Polymyxa sp. was observed after seed treatment with the bio-substances at our analysis time points. However, when we applied the bio-substances directly to soil a significant anti-Polymyxa graminis effect was obtained in roots of barley plants grown in the soil as well as in the treated soil. Despite germination can be affected by high concentrations of the substances, a range of antiviral protection conditions with no effect on germination were identified. Seed-treatment with the bio-substances did not negatively affect plant growth and development in virus-containing soil, but was rather beneficial for plant growth. We conclude that seed treatment with GE and Rha may represent an efficient, ecologically friendly, non-toxic, easy to apply and cost efficient biocontrol measure against soil-borne virus infection in plants.

Antifungal Activity of Difenoconazole-Loaded Microcapsules against Curvularia lunata.

Difenoconazole-loaded (CS-DIF) microcapsules were synthesized by encapsulating difenoconazole into biocompatible chitosan. The physical and chemical properties indicated that the encapsulation and chemical loading rates were 85.58% and 61.98%, respectively. The microcapsules exhibited prominent controlled-release and surface stability performance. The cumulative release rate was only 33.6% in 168 h, and the contact angle decreased by 11.73° at 120 s compared with difenoconazole. The antifungal activity of the CS-DIF microcapsules against Curvularia lunata was confirmed through observations of colony growth, in vitro and in vivo inoculation, mycelium morphology, as well as DNA and protein leakage. The antioxidant enzyme activity of superoxide dismutase, peroxidase, and catalase decreased by 65.1%, 84.9%, and 69.7%, respectively, when Curvularia lunata was treated with 200 μg/mL microcapsules, compared with the control in 24 h. The enzymatic activity of polyphenol oxidase decreased by 323.8%. The reactive oxygen species contents of hydrogen peroxide and superoxide anions increased by 204.6% and 164%, respectively. Additionally, the soluble sugar and soluble protein contents decreased by 65.5% and 69.6%, respectively. These findings provided a novel approach to control the growth of C. lunata efficiently, laying a foundation for reducing the quantity and enhancing the efficiency of chemical pesticides. The CS-DIF microcapsules exhibited a strong inhibitory effect on fungus, effectively preventing and controlling leaf spot disease and showing potential for field applications. This study might be of great significance in ensuring plant protection strategies.

AlphaFold-guided redesign of a plant pectin methylesterase inhibitor for broad-spectrum disease resistance

Plant cell walls are a critical site where plants and pathogens continuously struggle for physiological dominance. Here we show that dynamic remodeling of pectin methylesterification of plant cell walls is a component of the physiological and co-evolutionary struggles between hosts and pathogens. A pectin methylesterase (PsPME1) secreted by Phytophthora sojae decreases the degree of pectin methylesterification, thus synergizing with an endo-polygalacturonase (PsPG1) to weaken plant cell walls. To counter PsPME1-mediated susceptibility, a plant-derived pectin methylesterase inhibitor protein, GmPMI1, protects pectin to maintain a high methylesterification status. GmPMI1 protects plant cell walls from enzymatic degradation by inhibiting both soybean and P. sojae pectin methylesterases during infection. However, constitutive expression of GmPMI1 disrupted the trade-off between host growth and defense responses. We therefore used AlphaFold structure tools to design a modified form of GmPMI1 (GmPMI1R) that specifically targets and inhibits pectin methylesterases secreted from pathogens but not from plants. Transient expression of GmPMI1R enhanced plant resistance to oomycete and fungal pathogens. In summary, our work highlights the biochemical modification of the cell wall as an important focal point in the physiological and co-evolutionary conflict between hosts and microbes, providing an important proof of concept that AI-driven structure-based tools can accelerate the development of new strategies for plant protection.

Exopolysaccharides of lactic acid bacteria as protective agents against bacterial and viral plant pathogens

In this study, 25 exopolysaccharides produced by lactic acid bacteria (LAB) were screened for their effect on plant pathogens. The molecular masses of EPS were found to be 3,8-5,0 × 104 Da. The GC–MS analysis revealed that EPSs were majorly composed of glucose (85.85–97.98 %). The FT-IR spectra of EPSs were in agreement with the typical absorption peaks of polysaccharides. EPSs showed a hydroxyl radical scavenging ability. The scavenging rate of EPS ranged from 20 to 50 % at a concentration of 5.0 mg/mL. Significant growth delay of phytopathogenic bacteria was observed after 3–6 h of cultivation. Optical density values of indicator cultures growing in the medium with EPS (1 mg/mL) were lower compared to the control by 24–100 % for Pseudomonas fluorescens, 9–46 % for P. syringae, 47–79 % for Pectobacterium carotovorum, 14–90 % for Clavibacter michiganensis, 9–100 % for Xantomonas campestris, and 45–100 % for X. vesicatorium. EPS retained their inhibitory effect on the growth of X. campestris, X. vesicatorium and C. michiganensis strains after 24–48 h of cultivation, but stimulating effect on the growth of some strains also was observed. LAB EPS showed antibiofilm activity against P. carotovorum, P. syringae, and P. fluorescent, decreasing their biofilm formation by 16–50 %, 14–39 %, and 29–59 %, respectively. Also, stimulation of biofilm formation by X. campestris (by 8–29 %), X. vesicatorium (by 3–32 %) and C. michiganensis (by 31–41 %) strains was observed. EPSs showed antiviral activity against tobacco mosaic virus (TMV). At a concentration of 100 μg/mL, they decreased the infective ability of TMV by 61–92 %. This is the first study demonstrating that LAB EPS exhibited in vitro antibacterial and antibiofilm activity against phytopathogenic bacteria and anti-viral activity against TMV. Thus, LAB EPSs could have great potential for plant protection strategies.

Salinity stress alters plant-mediated interactions between above- and below-ground herbivores

Below-ground herbivory impacts plant development and often induces systemic responses in plants that affect the performance and feeding behavior of above-ground herbivores. Meanwhile, pest-damaged root tissue can enhance a plant's susceptibility to abiotic stress such as salinity. Yet, the extent to which herbivore-induced plant defenses are modulated by such abiotic stress has rarely been studied. In this study, we examine whether root feeding by larvae of the turnip moth, Agrotis segetum (Lepidoptera: Noctuidae) affects the performance of the above-ground, sap-feeding aphid Aphis gossypii (Hemiptera: Aphididae) on cotton, and assess whether those interactions are modulated by salinity stress. In the absence of salinity stress, A. segetum root feeding does not affect A. gossypii development. On the other hand, under intense salinity stress (i.e., 600 mM NaCl), A. segetum root feeding decreases aphid development time by 16.1 % and enhances fecundity by 72.0 %. Transcriptome, metabolome and bioassay trials showed that root feeding and salinity stress jointly trigger the biosynthesis of amino acids in cotton leaves. Specifically, increased titers of valine in leaf tissue relate to an enhanced performance of A. gossypii. Taken together, salinity stress alters the interaction between above- and below-ground feeders by changing amino acid accumulation. Our findings advance our understanding of how plants cope with concurrent biotic and abiotic stressors, and may help tailor plant protection strategies to varying production contexts.

PHYLOGENETIC CONNECTIONS AND COMPARISONS OF THE AMINO ACID SEQUENCES OF SEVERAL PEPTIDE INDUCERS OF MICROBIAL ORIGIN- A FOUNDATION STUDY FOR DEVELOPMENT OF NOVEL BIOPESTICIDES

Peptides of microbial origin stand out as one of theprominent tools to elicit plant immunity. These peptides comprise one of thekey strategies of integrated pest management and are considered as candidatesto develop novel biopesticides. Manyresearch investigations have proved their potential in fending off plantpathogens and were described as sustainable plant protection strategies. Thepresent study was attempted to discover phylogenetic relationships and compareamino acid sequence alignments of various peptide elicitors of microbialorigin. Phylogenetic analysis of 33 microbial peptide elicitors resulted in twoclusters, one cluster contained 19 flagellin sequences, which is furtherdivided into one major (15 peptide sequences) and one (4 peptide sequences)minor subclusters. Further amino acid sequence alignments were carried outbased on the evolutionary relationships among the peptides. The amino acidsequence alignment of flagellin sequences using Clustal W did not present conservativeamino acid sequences except Serine (S), Alanine (A) and Aspartic acid (D).These conserved amino acids (SAxD) that are positioned in the protruding loopmay play a vital role in recognition by plant surface receptors. Alignment ofamino acid sequences of cold shock protein, xylanase, elongation factor andharpin from various sources did not present conservative amino acid sequencesexcept glycine. These investigations lay a theoretical foundation for exploringmany more microbial peptides for inducing plant resistance.

Unlocking a Mystery: Characterizing the First Appearance of Clavibacter nebraskensis in Mexican Cornfields.

The Goss's wilt and leaf blight is a disease of maize (Zea mays) caused by Clavibacter nebraskensis, which was widespread in the last several years throughout the Midwest in the United States, south in Texas, and north to Canada. The bacterium is included within the high-risk list of quarantine pathogens by many plant protection organizations and countries including Mexico. Severe blight symptoms on maize plants were found in different provinces from Coahuila and Tlaxcala, Mexico, in 2012 and 2021, respectively. Twenty bacterial isolates with morphology similar to C. nebraskensis were obtained from the diseased maize leaves. The isolates were confirmed by phenotypic tests and 16S rRNA and gyrB sequencing. Two strains were tested for pathogenicity tests on seven hybrid sweet corn cultivars available in Mexico, and the most sensitive cultivar was tested for all the strains to fulfill Koch's postulates. The phylogenetic reconstruction based on two single loci reveals a remarkable clustering of Mexican strains to American strains reported approximately 50 years ago. The presence of this pathogen represents a risk and a significant challenge for plant protection strategies in Mexico and maize diversity.

Impacts of Soil Management and Sustainable Plant Protection Strategies on Soil Biodiversity in a Sangiovese Vineyard

Vine growing is one of the most economically important sectors of Mediterranean agriculture, but its cultivation practices are highly detrimental to the environment and the associated biota. The application of both natural products inducing endogenous plant defense mechanisms and natural soil management systems represents a potential solution for the preservation and improvement of soil health and biodiversity. The Life Green Grapes project aimed at evaluating the effects of different natural and sustainable vine protection strategies and soil management on vineyard edaphic communities. Soil TOC, TN, C:N ratio, CaCO3 content and pH were measured. Microbial communities (bacteria and fungi) were characterized through NGS, while nematodes and microarthropods were isolated and identified. Obtained data highlighted a relationshipbetween bacteria, fungi and nematodes with soil chemistry, and an effect of the different soil management on the single and total edaphic communities. Network analysis evidenced a positive effect of the application of sustainable soil managements on the relationships among the different investigated soil trophic levels, suggesting that more natural soil managements allow a better interaction between soil organisms. In conclusion, this work confirms the importance of the application of sustainable and natural soil management practices in agricultural ecosystems, with the aim of conserving and improving soil biodiversity.

Bacillus thuringiensis promotes systemic immunity in tomato, controlling pests and pathogens and promoting yield

AbstractPlant pathogens and pests pose an increasing threat to worldwide food security. To improve and strengthen food security under increasingly difficult environmental, economic, and geopolitical conditions, the prospect of using microbial biocontrol agents becomes increasingly desirable. One of the most studied, and commercially used, biopesticide microorganisms is the entomopathogenic, gram-positive, soil bacterium Bacillus thuringiensis (Bt). While Bt has been known for many years as an insecticidal microorganism and used extensively in agriculture, its possible anti-phytopathogen and plant growth-promoting activities have received comparatively limited attention thus far. Here, we examine the ability of Bt to promote systemic immunity in tomato plants. We investigate how Bt influences plant immunity and disease resistance against several fungal and bacterial plant pathogens, as well as several arthropod pests. In order to determine which component of Bt (i.e., Bt spores or pure crystals) is responsible for the observed effects on pathogens or pests, we dissected the different fractions present in a commercial preparation and assessed their effects on pest and pathogen control. As previously reported in the Bt literature, our results indicate that proteins produced by Bt are likely the primary acting components against pests. In the case of pathogens, however, it appears that both the Bt spores and proteins directly act against pathogens such as the fungus Botrytis cinerea. Bt Spores and produced proteins also both induce plant immunity. Understanding the different Bt mode of action mechanisms will help in developing cost-effective and safe plant protection strategies for enhancing food security. Taken together, our findings suggest that Bt could be used in broad-spectrum pest and disease management strategies. Pending validation in agricultural settings, Bt products on the market could have additional uses in sustainable pest management and plant growth promotion.

Deep neural network-based plant protection strategy in rural garden landscape construction

Rural landscaping enhances the quality of the environment in rural areas by planting trees and flowers and plants and at the same time can contribute to the protection of plants in rural areas. The occurrence and development of landscape plant diseases are very insidious, which may lead to poor tree growth and affect the annual growth of timber, or even lead to the death of the whole forest and the reverse succession of the forest. Plant leaf disease lesion location is random, and plant leaf image shooting is susceptible to light, background, angle and other objective factors can only rely on artificial identification, but the traditional artificial identification and physiological information extraction methods such as low accuracy, low efficiency and cumbersome. The rapid development of deep neural networks provides an effective solution for plant leaf recognition based on image analysis. In this paper, a DCA-ResNet model is constructed based on ResNet101 to recognize plant leaves by introducing the attention mechanism and optimizing the model structure. The validation of the DCA-ResNet model using public datasets on three species of plant leaves and plant leaf diseases achieved accuracy rates of 96.79%, 96.64%, and 96.44%, respectively.

An Effective and Promising Strategy for Plant Protection: Synthesis of L-Carvone-Based Thiazolinone-Hydrazone/Nanochitosan Complexes with Antifungal Activity and Sustained Releasing Performance.

The development of novel natural product-derived nano-pesticide systems with loading capacity and sustained releasing performance of bioactive compounds is considered an effective and promising plant protection strategy. In this work, 25 L-carvone-based thiazolinone-hydrazone compounds 4a~4y were synthesized by the multi-step modification of L-carvone and structurally confirmed. Compound 4h was found to show favorable and broad-spectrum antifungal activity through the in vitro antifungal activity evaluation of compounds 4a~4y against eight phytopathogenic fungi. Thus, it could serve as a leading compound for new antifungal agents in agriculture. Moreover, the L-carvone-based nanochitosan carrier 7 bearing the 1,3,4-thiadiazole-amide group was rationally designed for the loading and sustained releasing applications of compound 4h, synthesized, and characterized. It was proven that carrier 7 had good thermal stability below 200 °C, dispersed well in the aqueous phase to form numerous nanoparticles with a size of~20 nm, and exhibited an unconsolidated and multi-aperture micro-structure. Finally, L-carvone-based thiazolinone-hydrazone/nanochitosan complexes were fabricated and investigated for their sustained releasing behaviors. Among them, complex 7/4h-2 with a well-distributed, compact, and columnar micro-structure displayed the highest encapsulation efficiency and desirable sustained releasing property for compound 4h and thus showed great potential as an antifungal nano-pesticide for further studies.

A metapopulation framework integrating landscape heterogeneity to model an airborne plant pathogen: The case of brown rot of peach in France

Plant disease dynamics are driven by the concurrent interplay of host susceptibility, pathogen presence, and environmental conditions. While host susceptibility and environmental conditions can readily be characterized, the transmission of an airborne pathogen depends on the biotic and abiotic conditions of the surrounding environment. We propose an original metapopulation framework integrating landscape heterogeneity, in terms of climate and host density, where populations of plant hosts are connected via air-masses which allow pathogen dispersal. We explicitly account for climatic drivers affecting pathogen transport while modelling aerial dispersal using Lagrangian simulations, as well as host phenology and infection. We calibrate the model parameters according to the literature and using Approximate Bayesian Computation against observations of brown rot incidence in French peach orchards from 2001 to 2020 across an area of 50,000 km2. We use the model to produce maps of risk, distinguishing site dangerousness (risk of causing secondary infection in other sites) and vulnerability (risk of becoming infected) across the our study area. We demonstrate that airborne transport of Monilinia spores is essential in describing the spread of brown rot in French orchards in the considered period. We find that most dangerous and vulnerable sites are located along the Rhône Valley, due to the concurrence of high density of peach cultivation, a suitable climate and persistent airborne connections. Our work represents a first step to integrate metapopulation theory, epidemiology and air-mass movements to inform plant protection strategies at the national level. Furthermore, it could be adapted to optimize crop protection under future climate projections.

Argonaute and Dicer are essential for communication between Trichoderma atroviride and fungal hosts during mycoparasitism.

Trichoderma species are known for their mycoparasitic activity against phytopathogenic fungi that cause significant economic losses in agriculture. During mycoparasitism, Trichoderma spp. recognize molecules produced by the host fungus and release secondary metabolites and hydrolytic enzymes to kill and degrade the host's cell wall. Here, we explored the participation of the Trichoderma atroviride RNAi machinery in the interaction with six phytopathogenic fungi of economic importance. We determined that both Argonaute-3 and Dicer-2 play an essential role during mycoparasitism. Using an RNA-Seq approach, we identified that perception, detox, and cell wall degradation depend on the T. atroviride-RNAi when interacting with Alternaria alternata, Rhizoctonia solani AG2, and R. solani AG5. Furthermore, we constructed a gene co-expression network that provides evidence of two gene modules regulated by RNAi, which play crucial roles in essential processes during mycoparasitism. In addition, based on small RNA-seq, we conclude that siRNAs regulate amino acid and carbon metabolism and communication during the Trichoderma-host interaction. Interestingly, our data suggest that siRNAs might regulate allorecognition (het) and transport genes in a cross-species manner. Thus, these results reveal a fine-tuned regulation in T. atroviride dependent on siRNAs that is essential during the biocontrol of phytopathogenic fungi, showing a greater complexity of this process than previously established.IMPORTANCEThere is an increasing need for plant disease control without chemical pesticides to avoid environmental pollution and resistance, and the health risks associated with the application of pesticides are increasing. Employing Trichoderma species in agriculture to control fungal diseases is an alternative plant protection strategy that overcomes these issues without utilizing chemical fungicides. Therefore, understanding the biocontrol mechanisms used by Trichoderma species to antagonize other fungi is critical. Although there has been extensive research about the mechanisms involved in the mycoparasitic capability of Trichoderma species, there are still unsolved questions related to how Trichoderma regulates recognition, attack, and defense mechanisms during interaction with a fungal host. In this work, we report that the Argonaute and Dicer components of the RNAi machinery and the small RNAs they process are essential for gene regulation during mycoparasitism by Trichoderma atroviride.

Boosting Solanum tuberosum resistance to Alternaria solani through green synthesized ferric oxide (Fe2O3) nanoparticles

Potato (Solanum tuberosum) is the third crucial global crop facing threats from Alternaria solani, a necrotrophic fungal pathogen causing early blight disease. Beyond crop impact, it leads to substantial production reduction and economic losses worldwide. This study introduces a green synthesis method for producing Ferric Oxide nanoparticles (FNPs) using dried Guava (Psidium guajava) leaves. Guava leaf extract acts as a reducing agent, with iron (III) chloride hexahydrate (FeCl3·6H2O) as the oxidizing agent. This study employed various characterization techniques for Ferric Oxide nanoparticles (FNPs). Fourier Transform Infrared Spectroscopy (FTIR) revealed peaks at 877 cm−1, 1180 cm−1, 1630 cm−1, 1833 cm−1, 2344 cm−1, and 3614 cm−1, associated with Maghemite vibrations, polyphenol compounds, and amino acids. UV–Vis spectroscopy exhibited a characteristic absorbance peak at 252 nm for FNPs. Scanning Electron Microscope (SEM) images illustrated particle sizes of 29-41 nm, and Energy Dispersive Spectroscopy (EDS) indicated elemental composition. X-ray diffraction (XRD) confirmed crystalline FNPs with peaks at 26.78, 30.64, 36.06, 38.21, 43.64, 53.52, 57.42, 63.14 and 78.32. Disease resistance assays demonstrated FNPs’ effectiveness against A. solani, reducing disease incidence and severity. In the leaf detach assay, concentrations of 15, 10 and 5 mg/L showed a dose-dependent reduction in disease severity and incidence. The Greenhouse Assay confirmed FNPs’ concentration-dependent effect on disease incidence and severity. The study also explored FNPs’ potential as biocontrol agents showing no adverse effects on overall plant development. Additionally, the study highlighted the agronomic potential of FNPs in enhancing plant growth and development emphasizing their role as micronutrients in biofortification. The findings suggest the promising application of FNPs in plant protection and biofortification strategies.

Combatting Sugar Beet Root Rot: Streptomyces Strains' Efficacy against Fusarium oxysporum.

Sugar beet root rot disease triggered by Fusarium oxysporum f. sp. radicis-betae is a destructive disease and dramatically affects the production and quality of the sugar beet industry. Employing beneficial microorganisms as a biocontrol strategy represents an eco-friendly and sustainable approach to combat various plant diseases. The distinct aspect of this study was to assess the antifungal and plant growth-promoting capabilities of recently isolated Streptomyces to treat sugar beet plants against infection with the phytopathogen F. oxysporum. Thirty-seven actinobacterial isolates were recovered from the rhizosphere of healthy sugar beet plants and screened for their potential to antagonize F. oxysporum in vitro. Two isolates SB3-15 and SB2-23 that displayed higher antagonistic effects were morphologically and molecularly identified as Streptomyces spp. Seed treatment with the fermentation broth of the selected Streptomyces strains SB3-15 and SB2-23 significantly reduced disease severity compared to the infected control in a greenhouse experiment. Streptomyces SB2-23 exhibited the highest protective activity with high efficacy ranging from 91.06 to 94.77% compared to chemical fungicide (86.44 to 92.36%). Furthermore, strain SB2-23 significantly increased plant weight, root weight, root length, and diameter. Likewise, it improves sucrose percentage and juice purity. As a consequence, the strain SB2-23's intriguing biocontrol capability and sugar beet root growth stimulation present promising prospects for its utilization in both plant protection and enhancement strategies.

Assessing Phytotoxic Effects of Herbicides and Their Impact on Potato Cultivars in Agricultural and Environmental Contexts

Phytotoxicity refers to the capacity of chemical substances or environmental factors to have a negative impact on plants. This is a crucial issue in both the context of crop cultivation and environmental protection. The research results were based on a 3-year field experiment conducted at an experimental station in Jadwisin (52°28′ N, 21°02′ E) on loamy soil. The experiment was set up using a randomized sub-block design in a split–split–plot arrangement with three replications. The first-order factor consisted of potato cultivars, while the second-order factors were weed control methods: (1) without protection; (2) mechanical weed control, extensive mechanical treatments to close rows; (3) Sencor 70 WG—pre-emergence (PRE) of potatoes; (4) Sencor 70 WG + Titus 25 WG + Trend 90 EC—PRE of potatoes; (5) Sencor 70 WG—post-emergence (POST) of potatoes; (6) Sencor 70 WG + Titus 25 WG + Trend 90 EC—POST of potatoes; (7) Sencor 70 WG + Fusilade Forte 150 EC—POST of potatoes; and (8) Sencor 70 WG + Apyros 75 WG + Atpolan 80 SC—POST of potatoes. The phytotoxic effects of herbicides on potato plants and weeds were assessed every 7 days, starting from the date when the first signs of damage appeared until they stabilized or disappeared. Phytotoxic damage to potato and weed plants was caused by the chemical weed control methods used. The response of potato plants to herbicides was significantly related to the genetic traits of the cultivars and meteorological conditions in the years of research. Phytotoxicity is an important aspect in both agriculture and environmental protection. Research on its mechanisms and impact will enable the development of effective plant protection strategies and the preservation of ecosystem balance.