Synthetic Fungicides Research Articles

Biofungicides Based on Plant Extracts: On the Road to Organic Farming.

Phytopathogenic fungi are responsible for diseases in commercially important crops and cause major supply problems in the global food chain. Plants were able to protect themselves from disease before humans played an active role in protecting plants. They are known to synthesize a variety of secondary metabolites (SMs), such as terpenes, alkaloids, and phenolic compounds, which can be extracted using conventional and unconventional techniques to formulate biofungicides; plant extracts have antifungal activity and various mechanisms of action against these organisms. In addition, they are considered non-phytotoxic and potentially effective in disease control. They are a sustainable and economically viable alternative for use in agriculture, which is why biofungicides are increasingly recognized as an attractive option to solve the problems caused by synthetic fungicides. Currently, organic farming continues to grow, highlighting the importance of developing environmentally friendly alternatives for crop production. This review provides a compilation of the literature on biosynthesis, mechanisms of action of secondary metabolites against phytopathogens, extraction techniques and formulation of biofungicides, biological activity of plant extracts on phytopathogenic fungi, regulation, advantages, disadvantages and an overview of the current use of biofungicides in agriculture.

Synthesis and Evaluation of Copper Oleate Nanoparticles Against Citrus Anthracnose Caused by Colletotrichum gloeosporioides: In Situ Experiments, In Vitro Bioassays, and Field Trials

AbstractAnthracnose in citrus is a severe disease caused by Colletotrichum species. Synthetic fungicides have been used to combat this citrus disease; however, they may have adverse health effects on humans and cause harmful environmental impacts. During a search for environmentally friendly fungicides, we successfully prepared organic copper (copper (II) oleate) nanoparticles by using natural chitosan polymer as a coating agent and stabilizer and by combining an exchange reaction and in situ coating method. Organic copper nanoparticles coated with chitosan polymer (Cu‐oleate@CS NPs) with Cu contents ranged from 5.0 to 6.0 % by weight. The nanoparticles have an average particle size ranging from 50 nm to 60 nm (TEM), covered by a layer of polymer with a thickness of about 10 to 12 nm. The analytical results of zeta potential and dynamic solution size showed that the nanoparticles are uniformly dispersed (90–120 nm by DLS), with high stability (zeta potential=−61.7 mV) and low cytoxicity to Vero healthy cell line. Cu‐oleate@CS NPs significantly inhibited the mycelial growth of C. gloeosporioides in vitro at 500 and 1000 μg/mL. In field trials, the best antifungal efficacy of Cu‐oleate@CS NPs against citrus anthracnose on orange plants was found at a spray concentration of 0.33 % with a disease control efficacy of 54.18 % at 14 days after the second spraying. Our study results demonstrated a novel preparation of Cu‐oleate@CS NPs and suggested that it could be used as a promising nanoformulation to control citrus anthracnose in vitro and in vivo.

Exploring eco-friendly solutions for Phytophthora disease management: Harnessing the anti-oomycete potential of a fermented lemon waste formulation

Phytophthora species pose significant challenges to agricultural and natural ecosystems due to their ecological plasticity and ability to cause diseases of various plant species. Effective control of Phytophthora diseases requires integrated approaches that consider specific agronomic practices, environmental factors, and the rationale use of chemicals. In response to the need for eco-friendly alternatives, this study investigated the anti-oomycete potential of a formulation derived from the fermentation of lemon wastes by Lactiplantibacillus plantarum ('bioact-LM'). In vitro assays demonstrated the significant anti-oomycete efficacy of bioact-LM against multiple Phytophthora species, both through direct contact inhibition and the release of volatile organic compounds (VOCs). In vivo assessments on orange and apple fruits further confirmed the effectiveness of bioact-LM in reducing Phytophthora rot severity. These findings suggest bioact-LM is promising as a sustainable alternative to synthetic fungicide for Phytophthora disease management, highlighting the importance of exploring eco-friendly solutions in a scenario of environmental challenges and restriction in the use of conventional chemical control methods.

Effect Local Microorganisms Coconut Pulp in Increasing The Resistance of Red Chilli Plants To Fungus Colletotrichum acutatum J.H. Simmonds

The fungus Colletotrichum acutatum which often attacks chili plants causes anthracnose disease. Farmers generally use fungicides to control this disease. Continuous use of synthetic fungicides will have negative impacts. Plant extracts as an alternative to natural fungicides can be an appropriate and environmentally friendly choice. One of them is the use of Local Microorganisms (MOL). This research aims to determine the optimal concentration of coconut pulp MOL in increasing the resistance of red chilli plants to the fungus Colletotrichum acutatum that causes anthracnose disease. The study used a Totally Randomized Design (CRD) with 6 drugs, namely A (0 ml/water), B (5 ml/water), C (10 ml/water), D (15 ml/water), E (20 ml/water). ml/water), F (25 ml/water). There are four treatments each time. Information was broken down using ANOVA and continued with the Fair Genuine Contrast (BNJ) test at the 5% level (α = 5%). with a level of 5% (α = 5%). The results showed a significant effect on fungal colony diameter, germination period, plant height, plant incubation period, and disease severity. The best concentration of local coconut pulp microorganisms in inhibiting anthracnose disease was 25 ml/l water.

Antifungal activity of Cinnamomum camphora essential oil against Fusarium oxysporum and its application on postharvest blueberry fruits preservation

SummaryPostharvest decay of blueberry fruits caused by Fusarium oxysporum (F. oxysporum) results in significant losses during logistics. To avoid chemical residue issues associated with synthetic fungicides, present study investigated the antifungal activity of Cinnamomum camphora essential oil (CEO) against Fusarium oxysporum (F. oxysporum) in postharvest blueberry fruits. CEO effectively disrupted cell membrane integrity, impaired ergosterol structure, restricted ATPase activity and inhibits mycelial growth. Blueberries treated with a 0.2% CEO‐based coating demonstrated improved overall sensory acceptability, enhanced firmness, increased total soluble solids and titratable acidity, and reduced decay rate. CEO also decreased malondialdehyde contents while promoting ascorbic acid and glutathione levels and activating antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), maintaining cell membrane structure and enhancing resistance against F. oxysporum infection. The findings suggest that CEO serves as an eco‐friendly agent for mitigating primary fungal invasion in blueberries during postharvest storage.

Yeasts volatile organic compounds (VOCs) as potential growth enhancers and molds biocontrol agents of mushrooms mycelia

Volatile organic compounds (VOCs) produced by yeasts can positively affect crops, acting as antifungals or biostimulants. In this study, Aureobasidium pullulans and Metschnikowia pulcherrima were evaluated as potential antagonists of Trichoderma spp., common fungal pathogen in mushroom cultivation. To assess the biocontrol ability and biostimulant properties of the selected yeast species, in vitro co-culture and VOCs exposure assays were conducted. In both assays, VOCs produced by Aureobasidium spp. showed the stronger antifungal activity with a growth inhibition up to 30 %. This result was further confirmed by the higher volatilome alcohol content revealed by solid phase microextraction-gas chromatography mass spectrometry (SPME/GC–MS). Overall, Aureobasidium strains can be potentially used as biocontrol agent in Pleorotus ostreatus and Cyclocybe cylindracea mycelial growth, without affecting their development as demonstrated by VOCs exposure assay and Fourier-transform infrared spectroscopy (FT-IR). Conversely, M. pulcherrima was characterized by a lower or absent antifungal properties and by a volatilome composition rich in isobutyl acetate, an ester often recognized as plant growth promoter. As confirmed by FT-IR, Lentinula mycelia exposed to M. pulcherrima VOCs showed a higher content of proteins and lipids, suggesting an improvement of some biochemical properties. Our study emphasizes that VOCs produced by specific yeast strains are potentially powerful alternative to synthetic fungicide in the vegetative growth of mushroom-forming fungi and also able to modify their biochemical composition.

Antioxidant and Antifungal Properties of Cinnamon, Cloves, Melia azedarach L. and Ocimum gratissimum L. Extracts against Fusarium oxysporum Isolated from Infected Vegetables in Mauritius.

Fusarium species, a group of economically destructive phytopathogens, are poorly studied in Mauritius where agriculture holds much significance. Furthermore, the increasing popularity of organic farming has prompted interest in alternatives to chemical fungicides. After gaining an overview of Fusarium prevalence in Mauritius fields through a survey, the pathogen was isolated from infected crops and identified based on morphological and molecular characteristics. Methanol and water extracts were then prepared from Melia azedarach, Ocimum gratissimum, cinnamon and cloves before determining their phytochemical profiles. Additionally, the antioxidant and antifungal effects of different concentrations of aqueous extracts were assessed. The isolate was confirmed as Fusarium oxysporum, and cloves inhibited its growth by up to 100%, especially at 60 and 90 g/L, with the results being significantly higher than those of the synthetic fungicide mancozeb. Over 50% inhibition was also noted for cinnamon and Ocimum gratissimum, and these effects could be linked to the flavonoids, phenols and terpenoids in the extracts. This study presented the aqueous extracts of cloves, cinnamon and Ocimum gratissimum as potential alternatives to chemical fungicides. It also confirmed the prevalence of Fusarium infection in Mauritius fields, thereby highlighting the need for additional studies on the pathogen.

Impact of Various Essential Oils on the Development of Pathogens of the Fusarium Genus and on Health and Germination Parameters of Winter Wheat and Maize.

Currently, researchers are looking for ways to replace synthetic pesticides with substances of natural origin. Essential oils are produced by plants, among other things, to protect against pathogens, which is why there is interest in their use as fungicides. This experiment assessed the composition of essential oils from a commercial source, their impact on the development of mycelium of pathogens of the Fusarium genus, and the possibility of using them as a pre-sowing treatment. Grains of winter wheat (Triticum aestivum L.) and corn (Zea mays L.) were inoculated with a suspension of mycelium and spores of fungi of the Fusarium genus and then soaked in solutions containing oils of sage (Salvia officinalis L.), cypress (Cupressus sempervirens L.), cumin (Cuminum cyminum L.), and thyme (Thymus vulgaris L.). The obtained results indicate that thyme essential oil had the strongest effect on limiting the development of Fusarium pathogens and seedling infection, but at the same time it had an adverse effect on the level of germination and seedling development of the tested plants. The remaining essential oils influenced the mentioned parameters to varying degrees. Selected essential oils can be an alternative to synthetic fungicides, but they must be selected appropriately.

The fungicide cymoxanil impairs respiration in Saccharomyces cerevisiae via cytochrome c oxidase inhibition.

Cymoxanil (CYM) is a widely used synthetic acetamide fungicide, but its biochemical mode of action remains elusive. Since CYM inhibits cell growth, biomass production, and respiration in Saccharomyces cerevisiae, we used this model to characterize the effect of CYM on mitochondria. We found it inhibits oxygen consumption in both whole cells and isolated mitochondria, specifically inhibiting cytochrome c oxidase (CcO) activity during oxidative phosphorylation. Based on molecular docking, we propose that CYM blocks the interaction of cytochrome c with CcO, hampering electron transfer and inhibiting CcO catalytic activity. Although other targets cannot be excluded, our data offer valuable insights into the mode of action of CYM that will be instrumental in driving informed management of the use of this fungicide.

Exploration of the antifungal potential of aqueous extracts from two agave species against major postharvest diseases in apples

The apple tree, belonging to the Rosaceae family producing pome fruit, holds global economic significance. Despite this, apples face considerable postharvest disease challenges, particularly blue mold caused by Penicillium expansum and gray mold Botrytis cinerea. Synthetic fungicides are traditionally used for control, but their drawbacks necessitate exploring environmentally friendly alternatives. The current research investigates the antifungal activity of Agave americana and Agave sisalana aqueous extracts against these post-harvest diseases. In vitro tests demonstrated a concentration-dependent antifungal effect, with A. americana completely inhibiting mycelial growth and spore germination at 50 g L−1. A. sisalana exhibited a 75% reduction at the same concentration. A. americana at 6 g L−1 inhibited 50% of spore germination, while A. sisalana at 8 and 9 g L−1 achieved the same for B. cinerea and P. expansum. Regarding In vivo tests, both extracts reduced infection severity, particularly A. americana, which lowered gray mold and blue mold incidences to 23 and 26%. High polyphenol and flavonoid content in Agave extracts likely contributed to their efficacy. Phytochemical analyses identified 35 metabolites, including citric acid and piscidic acid, which are potential inhibitors of the fungal cell enzyme sterol 14 α-demethylase (CYP51), according to the results of molecular Docking analyses. Similarly, FTIR results indicated compounds with significant antimicrobial activity. Importantly, these biological treatments preserved apple quality during storage, suggesting their potential as effective and sustainable alternatives to synthetic fungicides.

Formulation of essential oils-loaded solid lipid nanoparticles-based chitosan/PVA hydrogels to control the growth of Botrytis cinerea and Penicillium expansum

Botrytis cinerea and Penicillium expansum are phytopathogenic fungi that produce the deterioration of fruits. Thus, essential oil (EO) has emerged as a sustainable strategy to minimize the use of synthetic fungicides, but their volatility and scarce solubility restrict their application. This study proposes the EO of Oreganum vulgare and Thymus vulgaris-loaded solid lipid nanoparticles (SLN) based chitosan/PVA hydrogels to reduce the infestation of fungi phytopathogen. EO of O. vulgare and T. vulgaris-loaded SLN had a good homogeneity (0.21–0.35) and stability (−28.8 to −33.0 mV) with a mean size of 180.4–188.4 nm. The optimization of EO-loaded SLN showed that the encapsulation of 800 and 1200 μL L−1 of EO of O vulgare and T. vulgaris had the best particle size. EO-loaded SLN significantly reduced the mycelial growth and spore germination of both fungi pathogen. EO-loaded SLN into hydrogels showed appropriate physicochemical characteristics to apply under environmental conditions. Furthermore, rheological analyses evidenced that hydrogels had solid-like characteristics and elastic behavior. EO-loaded SLN-based hydrogels inhibited the spore germination in B. cinerea (80.9 %) and P. expansum (55.7 %). These results show that SLN and hydrogels are eco-friendly strategies for applying EO with antifungal activity.

Deciphering Nature’s Secret of Seaweed Extract as a Biostimulant on Horticultural Crops: A Review

Seaweed extracts have gained significant attention in horticultural practices due to their diverse range of beneficial effects on plant growth, development, and stress tolerance. The presence of antioxidants and Osm-protectants in seaweed extracts helps mitigate oxidative damage and maintain cellular integrity under adverse conditions. It also holds great promise as a valuable input in horticultural systems, offering a range of benefits including enhanced soil health, and sustainability. This review aims to summarize and analyze the benefits of seaweed extract application on horticultural crops. The extracts derived from seaweed are rich in essential nutrients which are available from through which plants can absorb easily and promote growth. It also contains numerous bioactive compounds including cytokinins, auxins, gibberellins, and betaines, which act as plant growth regulators. The application of seaweed extracts can induce systemic acquired resistance (SAR) in plants, triggering defense mechanisms against pathogens and pests, which can reduce the need for synthetic pesticides and fungicides, promoting sustainable and environmentally friendly horticultural practices. In addition to its direct effects on plants, seaweed extract enhances soil health and microbial activity. It serves as a natural biostimulant, promoting beneficial microbial populations in the rhizosphere, which facilitate nutrient uptake and cycling. Moreover, the humic substances present in seaweed extract contribute to soil structure improvement, water retention, and nutrient availability, fostering a conducive environment for plant growth.

Anti-black pod disease activity of leaf extract of Carica papaya Linn

BackgroundTheobroma cacao (Cocoa) is a major foreign exchange earner for Ghana. Over the recent decades, there has been a consistent decline in cocoa production in the country. A major contributing factor is the cocoa black pod disease caused by Phytophthora species. Synthetic fungicides have been used to control the pathogens over the years. However, recent calls for organic cocoa devoid of residues from synthetic fungicides, which are known to pose several health challenges as well as a negative impact on the environment, have gained attention. Thus, inviting investigations into more environmentally friendly and sustainable alternatives to synthetic fungicides. ObjectiveThis study explored the inhibitory potential of crude extract from Carica papaya against cocoa black pod disease caused by Phytophthora spp. Material and methodsAn in-silico study was done using known phytochemicals from Carica papaya as ligands against a Phytophthora effector protein. Crude extracts were obtained from the plant materials using 70 % ethanol as the extraction solvent. The crude Green Leaf Extract (GLE), Aging Induced Chlorophyll Deficient Leaf Extract (AICDLE), and Matured Black Seed Extract (SDE) were tested in-vitro against pre-cultured P. palmivora and P. megakarya using the poison food technique. GLE was modulated with Delco, a synthetic fungicide, at different ratios which were tested in-vitro and in-vivo. ResultsA total of 16 ligands showed binding affinity higher or equal to the standard ligand, alliin, suggesting Carica papaya as a repository of anti-phytophthora agents. Assessment of crude extracts at concentrations 5–20 mg/ml showed fungistatic activity against P. palmivora and P. megakarya in-vitro. Modulation of GLE with Delco produced some combinations that made GLE fungicidal in-vitro against P. palmivora and P. megakarya with fractional inhibition concentration indices between 0.51 and 0.65, interpreted as partially synergistic. The in-vivo assessment of combination D (Delco and GLE in a 0.3 mg:3 mg per ml ratio) performed as well as Delco alone at the recommended dose of 5 mg/ml. Thus, combination D reduces the requirement for copper-based fungicide by over 90 %. ConclusionThis study shows Carica papaya in a new light as a potential material that could be formulated into a natural product-based fungicide for combating Phytophthora-induced black pod disease.

Integration of mathematical modeling and target-based application of biocontrol agents for the control of Botrytis cinerea in vineyards.

Biocontrol agents (BCAs) are alternatives to synthetic fungicides with low risk to the environment and human health. Although several studies on the biocontrol of gray mold in vineyards have been performed, it is necessary to improve the usage of BCAs in fields conditions. Therefore, in the present study, BCAs were used both in calendar-based [based on four growth stages (GSs), i.e., flowering, pre-bunch closure, veraison, and before harvest] and predictive model-based strategies (only when Botrytis cinerea infection risk was predicted by the model). The BCAs applied during the seasons were selected considering the grapevine GSs. Treatments performed with BCAs were compared with synthetic fungicide treatments and an untreated control. The trials were conducted in three experimental vineyards with four epidemics. To evaluate the level of gray mold control of each treatment, disease severity was assessed at harvest and the presence of latent infection was evaluated. The integrative use of the predictive model and BCAs provided satisfactory levels of gray mold control, with gray mold severity levels significantly lower (P < 0.001) than those of the untreated control, which had severity values (< 7%) similar to those observed with synthetic fungicides following both calendar and model-based strategies. The integrative use of the predictive model and BCAs represents a valid alternative to conventional methods of gray mold control in vineyards, with more than 75% reduction in fungicide usage. © 2024 Society of Chemical Industry.

Visible Light-Gating Responsive Nanochannel for Controlled Release of the Fungicide.

Fungicides have been widely used to protect crops from the disease of pythium aphanidermatum (PA). However, excessive use of synthetic fungicides can lead to fungal pathogens developing microbicide resistance. Recently, biomimetic nano-delivery systems have been used for controlled release, reducing the overuse of fungicides, and thereby protecting the environment. In this paper, inspired by chloroplast membranes, visible light biomimetic channels are constructed by using retinal, the main component of green pigment on chloroplasts in plants, which can achieve the precise controlled release of the model fungicide methylene blue (MB). The experimental results show that the biomimetic channels have good circularity after and before light conditions. In addition, it is also found that the release of MB in visible light by the retinal-modified channels is 8.78 µmol·m-2·h-1, which is four times higher than that in the before light conditions. Furthermore, MB, a bactericide drug model released under visible light, can effectively inhibit the growth of PA, reaching a 97% inhibition effect. The biomimetic nanochannels can realize the controlled release of the fungicide MB, which provides a new way for the treatment of PA on the leaves surface of cucumber, further expanding the application field of biomimetic nanomembrane carrier materials.

Bioassay-guided isolation of three new alkaloids from Suillus bovinus and preliminary mechanism against ginseng root rot.

In order to control the occurrence of ginseng root rot caused by Fusarium solani (Mart.) Sacc., the antifungal compounds of the mushroom Suillus bovinus were investigated. And three new alkaloids (1-3), named bovinalkaloid A-C, along with one known analog (4), were isolated and identified by bioassay-guided isolation and spectroscopic analyses. Compound 1 strongly inhibited the mycelial growth and spore germination of F. solani with minimum inhibitory concentration of 2.08 mM. Increases in electrical conductivity, nucleic acid, and protein contents, and decreases in lipid content showed that the membrane permeability and integrity were damaged by compound 1. Compound 1 also increased the contents of malondialdehyde and hydrogen peroxide and the activities of antioxidant enzymes, indicating that lipid peroxidation had taken place in F. solani. Compound 1 may serve as a natural alternative to synthetic fungicides for the control of ginseng root rot.

In vitro inhibition of Fusarium spp. isolated from bean crop using Argemone ochroleuca extract

Species of the genus Fusarium are the main cause of root rot in bean crops, resulting in yield losses of up to 50%. Synthetic fungicides are the primary tools for their control; however, they cause environmental damage. The objective of this study was to evaluate the effect of extracts from A. ochroleuca on Fusarium spp. under in vitro conditions. During the spring-summer 2022 growing season, plants exhibiting symptoms of wilting and vascular browning were collected. The isolated fungi were purified through monosporic cultures and hyphal tip techniques, and their morphological characteristics were characterized. To determine growth inhibition, a poisoned medium methodology was employed, evaluating two concentrations of extracts (13% and 23%) in both ethanol and aqueous mediums. The obtained isolates corresponded to the morphological characteristics of Fusarium. The extract volumes that showed 100% inhibition were the 23% concentration in both ethanol and aqueous mediums. The 13% ethanol extract exhibited inhibition ranging from 29% to 62% between the first and tenth day of incubation. The 13% aqueous extract displayed inhibition ranging from 25% to 43%. The Argemone ochroleuca extract demonstrates antifungal properties against Fusarium spp. isolated from beans.

Chemical, antioxidant, and antifungal analysis of oregano and thyme essential oils from Ecuador: Effect of thyme against Lasiodiplodia theobromae and its application in banana rot

The objective of this study was to evaluate the antioxidant capacity by spectrophotometric methods, the in vitro and in vivo antifungal effect against Lasiodiplodia theobromae and the constitution of the essential oils (EO) of oregano and thyme in comparison with their commercial counterparts. The results showed by the EOs of extracted thyme (T-EO), commercial thyme (CT-EO), extracted oregano (O-EO) and commercial oregano (CO-EO), demonstrated antioxidant profiles with a radical neutralizing potential (DPPH•) of IC50: 1.11 ± 0.019; 1.08 ± 0.05; 40.56 ± 0.227 and 0.69 ± 0.004 mg/mL, respectively. They also revealed a ferric ion reducing capacity (FRAP) of 93.05 ± 0.52; 97.72 ± 0.42; 21.85 ± 0.57 and 117.24 ± 0.64 mg Eq Trolox/g. A reduction in β-carotene degradation of 65.71 ± 0.04; 51.97 ± 0.66; 43.58 ± 1.56 and 57.46 ± 1.56 %. A total phenol content (Folin-Ciocalteu) of 132.97 ± 0.77; 141.89 ± 2.56; 152.04 ± 0.10 and 25.66 ± 0.40 mg EGA/g. Chemical characterization performed by gas chromatography mass spectrometry (GC-MS) showed that the respective major components of the samples were thymol (T-EO: 45.78 %), thymol (CT-EO: 43.57 %), alloaromadendrene (O-EO: 25.17 %) and carvacrol (CO-EO: 62.06 %). Regarding antifungal activity, it was evident that at the in vitro level, both commercial EOs had a MIC of 250 ppm while the extracted thyme EO had a MIC of 500 ppm; In vivo studies demonstrated that the application of thyme EO had a behavior similar to the synthetic fungicide, slowing down rot in bananas under storage conditions. Finally, partial least squares discriminant analysis (PLS-DA) and heat maps suggest p-cymene, carvacrol, linalool, eucalyptol, 4-terpineol, (z)-β-terpineol, alkanhol, caryophyllene, β-myrcene, d-limonene, α-terpinene, α-terpineol, d-α-pinene, camphene, caryophyllene oxide, δ-cadinene, terpinolene and thymol as relevant biomarkers associated with the assessed bioactive properties demonstrating the potential of extracted essential oils for the development of a botanical biofungicide.

The mechanistic insights of essential oil of Mentha piperita to control Botrytis cinerea and the prospection of lipid nanoparticles to its application

Botrytis cinerea is the phytopathogenic fungus responsible for the gray mold disease that affects crops worldwide. Essential oils (EOs) have emerged as a sustainable tool to reduce the adverse impact of synthetic fungicides. Nevertheless, the scarce information about the physiological mechanism action and the limitations to applying EOs has restricted its use. This study focused on elucidating the physiological action mechanisms and prospection of lipid nanoparticles to apply EO of Mentha piperita. The results showed that the EO of M. piperita at 500, 700, and 900 μL L−1 inhibited the mycelial growth at 100 %. The inhibition of spore germination of B. cinerea reached 31.43 % at 900 μL L−1. The EO of M. piperita decreased the dry weight and increased pH, electrical conductivity, and cellular material absorbing OD260 nm of cultures of B. cinerea. The fluorescence technique revealed that EO reduced hyphae width, mitochondrial activity, and viability, and increased ROS production. The formulation of EO of M. piperita loaded- solid lipid nanoparticles (SLN) at 500, 700, and 900 μL L−1 had particle size ∼ 200 nm, polydispersity index < 0.2, and stability. Also, the thermogravimetric analysis indicated that the EO of M. piperita-loaded SLN has great thermal stability at 50 °C. EO of M. piperita-loaded SLN reduced the mycelial growth of B. cinerea by 70 %, while SLN formulation (without EO) reached 42 % inhibition. These results supported that EO of M. piperita-loaded SLN is a sustainable tool for reducing the disease produced by B. cinerea.

Antifungal Potential of Ocimum sanctum Linn. Essential Oil against Fungal Pathogens Causing Economic Losses in Cymbopogon flexuosus Nees Ex Steud. (Lemongrass)

Cymbopogon flexuosus Nees Ex Steud. (Commonly known as lemongrass, family Poaceae) is one of the commercially important aromatic plants having medicinal properties. India is one of the largest producers and exporters of lemongrass essential oil in the world; in the year 2021-22, India exported about 610 tons of lemongrass oil, contributing more than 4 lakh US $ million in Gross Domestic Productivity (GDP). However, despite a good national and international market, this crop suffers quantitative and qualitative losses due to the leaf spot and leaf blight diseases caused by the fungi Curvularia trifolii and Rhizoctonia solani, respectively; therefore, an attempt has been made to manage these fungal pathogens. The essential oil of basil (Ocimum sanctum Linn.) was extracted by hydro-distillation method using Clevenger apparatus. The oil thus extracted was used for in vitro antifungal efficacy against both the test fungi Curvularia trifolii and Rhizoctonia solani, using the poison food technique. The results show that the minimum inhibitory concentration (MIC) of the basil oil against C. trifolii 2000 ppm and R. solani was 1600 and however, it was cidal in nature at 3200 and 2400 ppm against both fungi, respectively. The current study’s findings show that O. sanctum oil could be an alternative to synthetic fungicides after detailed investigations.