Controlled-Release of Plant Volatiles:New Composite Materials of Porous Carbon-Citral and Their Fungicidal Activity against Exobasidium vexans

Citral(Eo)exhibits excellent fungicidal activities.However,it is difficult to maintain long-term fungicidal activity due to its strong volatility.Herein,a controlled-release strategy by using biomass-derived porous carbon(BC)was developed to overcome the drawback of Eo.New composite materials were prepared by loading Eo on tea stem porous carbon(BC@Eo),and their controlled-release fungicidal activity against Exobasidium vexans was assessed.BC with a large specific surface area of 1001.6 m2/g and mesoporous structure was fabricated through carbonization tempera-ture of 700℃.The BC@Eo materials were characterized using Fourier-transform infrared spectroscopy and X-ray powder diffraction.The results suggested that chemical and physical interactions occurred in BC@Eo.The Eo release profile suggested a biphasic pattern with an initial fast release on days 1–14 and a subsequent controlled phase on days 14–30.The in vitro cumulative release percentage of Eo from BC@Eo was 51%during one month,and this result was significantly lower than that from free Eo(cumulative release percentage of Eo of 82%in one week).The anti-fungal activities of Eo and BC@Eo against E.vexans were determined using the inhibition zone method.The results indicated that Eo and BC@Eo formed large inhibition zones of 19.66±0.79 and 21.92±0.77 mm,respectively.The influence on the hyphal structure of E.vexans was observed by scanning electron microscopy on day 30.The hyphal structure of E.vexans treated with BC@Eo was more shrunken than that treated with Eo at 30 days,suggesting that BC@Eo prolongs the fungicidal activity against E.vexans.This study demonstrated that the encapsulation of Eo in BC for developing the BC@Eo materials could be a promising strategy to inhibit volatility and maintain the fungicidal activity of Eo and provide a potential alternative for the reuse of abundant tea biomass waste resources.

Synthesis, Crystal Structure and Fungicidal Activity of N-(4-tert-buty)-5-(1,2,4-triazol-1-yl)thiazol-2-yl)propionamide

The title compound has been synthesized by the reaction of 4-tert-butyl-5-（1,2,4- triazol-1-yl）-2-aminothiazole with propionic anhydride, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pbca with α = 18.441（2）, b = 8.3284（9）, c = 19.257（2） A, Z = 8, V = 2957.5（5） A3, Mr = 279.37, Dc = 1.255 mg/m3, S = 1.033, μ =0.219 mm^-1, F（000） = 1184, the final R = 0.0349 and wR = 0.0876 for 2629 observed reflections （I 〉 2σ（I））. X-ray crystal structure presents the intermolecular N–H···N hydrogen bond, which plays an important role in stabilizing the crystal structure. The preliminary bioassay indicates that the title compound exhibits potent fungicidal activity against R. Solani （25 mg/L） with inhibition rate of 80.0%.

Synthesis, Crystal Structure and Fungicidal Activity of (Z)-3,3-Dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-one O-2-Chlorobenzyl Oxime Nitrate

The title compound has been synthesized by the reaction of 3,3-dimethyl-1-（1H-1,2,4-triazol-1-yl）butan-2-one oxime with 2-chlorobenzyl chloride, and then treated with 65～68% HNO3. Its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 14.5481（8）, b = 9.3351（5）, c = 13.1911（7） , β = 98.9450（10）°, Z = 4, V = 1769.67（17） 3, Mr = 369.81, Dc = 1.388 g/cm3, S = 1.06, μ = 0.247 mm-1, F（000） = 776, the final R = 0.0352 and wR = 0.0960 for 3069 observed reflections （I 2σ（I））. X-ray crystal structure presents the intramolecular N–H…O hydrogen bond. The packing is nearly parallel without π-π stacking interactions between two adjacent phenyl rings and stabilized by Van der Waals force. The preliminary bioassay shows that the title compound possesses fungicidal activity against Gibberella zeae at the dosage of 25 mg/L.

Synthesis,Crystal Structure and Fungicidal Activity of(E)-2-[(4-tert-Butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol

The title compound （E）-2-[（4-tert-butyl-5-（4-methoxybenzyl）thiazol-2-ylimino）methyl]phenol was synthesized by the reaction of 5-（4-methoxybenzyl）-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 5.9362（8）, b = 11.5070（15）, c = 29.460（4）A, β= 97.326（3）°, V = 1995.9（5） A^3, Z = 4, F（000） = 808, C22H24N2O2S, Mr= 380.49, De= 1.266 g/cm^3, S = 1.031,μ = 0.181 mm^-1, the final R = 0.0474 and wR = 0.1441 for 4327 observed reflections （I 〉 2σ（I））. Intramolecular O-H…N hydrogen bond is observed in the crystal. The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L.

Synthesis, Crystal Structure and Fungicidal Activity of 3-(4-Chloro-3-ethyl-1-methyl-1H-pyrazol-5-yl)-6-(E)phenylvinyltriazolo[3,4-b]-1,3,4-thiadiazole

The crystal structure of the title compound 3 (4 Chloro 3 ethyl 1 methyl 1H pyrazol 5 yl) 6 (E)phenylvinyltriazolo[3,4 b] 1,3,4 thiadiazole (C 17 H 15 ClN 6S, M r =370.87) was determined by single crystal X ray diffraction. The crystal is monoclinic, space group P2 1/n , a=10.862(2), b=11.541(2), c=14\^994(3), β=108.41(3)°, V=1783(1), Z=4, D x =1.381 g/cm -3 , μ =0.3361 mm -1 , and F (000)=768. The results confirmed that the title compound belongs to type E of stereochemistry. The dihedral angle between triazole and 1,3,4 thiadiaole ring is 3° and the torsion angle between 1,3,4 thiadiazole and pyrazole ring is 134.0°.

Synthesis and Fungicidal Activity of Chlorothalonil Derivatives

[Objective]The paper was to develop a novel fungicide with high efficacy and low toxicity.[Method]Chlorothalonil was used as the parent structure,and its 4-position substituent was converted to amino group.Totally 12 amide compounds not reported in the literature were designed and synthesized.Their structures were conformed by 1H NMR.[Result]The preliminary bioassay test showed that compounds JTCN-01,JTCN-05 and JTCN-07 had good control effect on corn rust at the concentration of 200 mg/L,and the control effect of compound JTCN-05 reached 95%.[Conclusion]Some chlorothalonil derivatives had the potential for further development.

Synthesis and Fungicidal Activity of Some Novel Thiazole Schiff Bases Derived from Benzo[d][1,3]dioxole

A series of novel thiazole Schiff base derivatives containing benzo[d][1,3]dioxole moiety was designed, synthesized and screened for their fungicidal activities. The preliminary results demonstrated that compounds 6p, 6q and 6r possessed potent activities against Phytophthora infestans, Pyricularia oryzae and Septoria tritici in vitro. Compounds 6d and 6r exhibited remarkable activities against Botrytis cinerea（whole plant） and Phytophthora in- festans（leaf disk） respectively in vivo, which were identified as the most promising candidates for further study and could be used as possible lead compounds for developing new fungicides.

Synthesis and fungicidal activity study of novel daphneolone analogs with 2,6-dimethylmorpholine

A series of novel daphneolone analogs was designed and synthesized on the basis of natural product 1,5-diphenyl-2-penten-1-one（I） from Stellera chamaejasme L. as lead compound, whereby 2,6-dimethylmorpholine moiety was introduced to replace 1-phenyl group. Their structures were confirmed by IR,1H NMR, and HRMS（ESI） or elemental analysis,13 C NMR for some representative compounds. The two isomers of target compounds were separated and identified by NOESY technique and chemical method.All of the synthesized compounds have been evaluated for anti-plant pathogenic fungi activities. The results showed that some compounds exhibited moderate to good antifungal activities against tested fungi at the concentration of 50 mg/L. Among them, compound 7d, with a 4-bromine-substituted phenyl group and cis-2,6-dimethylmorpholine moiety, displayed best activity with an EC50 of 23.87 mmol/L against Valsa mali, superior to lead compound I. In addition, preliminary structure–activity relationship analysis indicated that, between two isomers of target compounds, the antifungal activities of the isomer with cis-2,6-dimethylmorpholine were better than the trans-isomer.

Synthesis, Crystal Structure and Fungicidal Activity of 3-Chloro-4-(3,4-dichloroisothiazol-5-yl)-5-hydroxy-7-methyl-2H-chromen-2-ones

3-Chloro-4-(3,4-dichloroisothiazol-5-yl)-5-hydroxy-7-methyl-2 H-chromen-2-ones,a kind of coumarin derivatives,were synthesized byβ-ketoester formation and cyclization.Target compound 5 e was crystallized from methanol for structural identification as monoclinic crystal system,space group C2/c with a=16.2700(6),b=7.1801(5),c=23.4861(10)A,V=2742.6(2)A^(3),Z=8,Dc=1.756 g/cm^(3),F(000)=1456 andμ=0.827 mm-1.8308 Reflections were collected(6.01≤2θ≤50.05°),of which 2428 were unique(Rint=0.0432)and used in all calculations.The final R=0.0408(I>2σ(I))and w R=0.1056(reflections).In vitro bioassay indicated that compounds 5 d&5 e possessed good activity against Botrytis cinerea,Physalospora piricola,Rhizoctonia solani,and Sclerotinia sclerotiorum with lower EC50 values falling between 0.50 and 4.85μg/m L than that of positive control osthole with its EC50 values between 7.38 and 74.59μg/mL.In vivo screening showed that 5 e exhibited 98%and 95%efficacy against Pseudoperonospora cubensis(Berk.&Curt.)Rostov.at 100 and 50μg/mL,respectively.Our studies discovered that the combination of bioactive substructures of isothiazole with coumarin was an effective way to novel fungicide development.

Synthesis,Crystal Structure and Fungicidal Activity of 3,4-Dichloro-5-(6-chloro-9-(4-fluorobenzyl)-9H-purin-8-yl)isothiazole

3,4-Dichloro-5-(6-chloro-9-(4-fluorobenzyl)-9H-purin-8-yl)isothiazole,a novel purine derivative,was synthesized by the cyclization of pyrimidine amine.Its structure was characterized by ^(1)H NMR,^(13)C NMR,^(19)FNMR,H RMS and single-crystal X-ray diffraction.This compound 3 is crystallized from a mixed solvent of dichloromethane and n-hexane (1:2,v/v) for structural identification as monoclinic crystal system,space group P2_(1)/n with a=11.66250(10),b=8.21300(10),c=17.77920(10)?,V=1676.34(3)?^(3),Z=4,D_(c)=1.643 g/cm^(3),F(000)=832.0 andμ=6.301 mm^(-1).22315 reflections were measured (8.43≤2θ≤158.10°),of which 3532 were unique (R_(int)=0.0311) and used in all calculations.The final R=0.0334 (I>2σ(I)) and w R=0.0842 (reflections).The title compound showed over 50%of growth inhibition against Botrytis cinereal,Cercospora arachidicola,Gibberella zeae,Rhizoctonia solani and Sclerotinia sclerotiorum at 50 mg/L,and its EC_(50) value against R.solani was 60.44μmol/L,which was active at the same level as that of positive control diflumetorim with its EC_(50) value of 60.29μmol/L and less active than YZK-C22 with its EC_(50) value of 12.32μmol/L,respectively.Our studies discovered that the combination of bioactive substructures of isothiazole with purine could be an effective way to novel fungicide development.

Synthesis and Fungicidal Activity of （E）-5-[1-（2-Oxo- 1 -oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2- aminoimidazolin-4-one Derivatives

The novel fungicidal agents, （E）-5-[1-（2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS, 1H NMR and X-ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e, 6a, 6e, and 7h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum, 3b, 3c, 4c and 7h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 μg/mL, respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56 --11.60 μg/mL, and compounds 6e and 7h exhibited weak inhibition against the spore germination of S. scleoti- orum, while the spore germination ofP. capsici was strongly inhibited by compound 7h solution. Scanning electron microscopy （SEM） and transmission electron microscopy （TEM） observation indicated that compound 7h had a significant impact on the structure and function of the hyphal cell wall ofP. capsici mycelium.

Synthesis, Crystal Structure and Biological Activity of 1,5-Bis(4-methoxyphenyl)-3-(4-methyl-1,2,3-thiadiazol-5-yl)pentane-1,5-dione

The title compound 1,5-bis（4-methoxyphenyl）-3-（4-methyl-1,2,3-thiadiazol-5-yl）-pentane-1,5-dione （C22H22N2O4S, Mr=410.49） has been synthesized by the reaction of 4-methyl-1,2,3-thiadiazole-5-carbaldehyde with 4-methoxyacetophenone, and its structure was characterized by IR, 1H NMR, H RMS, elemental analysis and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic, space group P21/c with a=11.159（3）, b=9.002（3）, c=20.192（6）, β=93.393（5）°, Z=4, V=2024.6（10） 3 , Dc=1.347 g/cm3 , μ=0.191 mm-1 , F（000）=864, R=0.0333 and wR （I〉2σ （I））=0.0840. In this molecule, the 1,2,3-thiadiazol ring is nearly vertical with both phenyl rings, and intermolecular weak hydrogen bonds of C-H…O and C-H…N types together with π-π stacking interactions and interactions between S（1）…N（2） are observed. The above three kinds of interactions extend the molecules into a two-dimensional layer framework. The preliminary biological test showed that the title compound had fungicidal activity.

Design, Synthesis, and Biological Activity of Novel Aromatic Amide Derivatives Containing Sulfide and Sulfone Substructures

In recent years,the damage caused by soil nematodes has become increasingly serious;however,the varieties and structures of the nematicides available on the market are deficient.Fluopyram,a succinate dehydrogenase inhibitor(SDHI)fungicide developed by Bayer AG in Germany,has been widely used in the prevention and control of soil nematodes due to its high efficiency and novel mechanism of action.In this paper,two series of novel target compounds were designed and synthesized with nematicidal and fungicidal fluopyram as the molecular skeleton in order to introduce sulfide and sulfone substructures.The structures were identified and characterized by 1H nuclear magnetic resonance(NMR),13C NMR,and high-resolution mass spectrometer(HRMS).The bioassays revealed that most of the compounds showed excellent nematicidal activities at 200 lgmL-1 in comparison with fluopyram,while the nematode mortality rate dropped sharply at 100μg·mL-1,except for compounds I-11 and II-6.In terms of fungicidal activity,compound I-9 was discovered to have an excellent inhibitory rate,and a molecular docking simulation was performed that can provide important guidance for the design and exploration of efficient fungicidal lead compounds.

Synthesis and Fungicidal Activities of 2-Alkylthio-5-(3,4,5-tribenzyloxyphenyl)-1,3,4-oxadiazoles

Abstract： Ten novel 2-alkylthio-5-（3, 4, 5-tribenzyloxyphenyl）-1, 3, 4-oxadiazole derivatives （5a-j） were synthesized from methyl 3, 4, 5-trihydroxybenzoate by ethedfication, hydrazidation, cyclization and thioetherification reactions. The structures of 5a-j were confirmed by 1HNMR, MS spectra and elemental analysis. The results indicated that most of the compounds 5 exhibited good fungicidal activities. The activity of 5h is higher than 90% against Fusarium oxysporum and Botrytis cinereapers in 50 mg/L.

Synthesis, Crystal Structure and Biological Activity of 5-(2-Methylphenyl)-1,3,4-oxadiazol-2(3H)-one Derivatives

3-Methyl-5-（2-methylphenyl）-1,3,4-oxadiazol-2（3H）-one （6） and N,N-diethyl-2-（2- methylbenzoyl）-hydrazinecarboxamide （7） were designed and synthesized from 5-（2-methyl- phenyl）- 1,3,4-oxadiazol-2（3H）-one （5） by substituting and ring-opening, respectively. The target compounds were confirmed by IR, JH NMR spectroscopy, MS, elemental analysis and single-crystal X-ray diffraction. Compound 6 （Cl0Hl0N202, Mr = 190.20） crystallizes in the triclinic system, space group P1 with a = 7.4645（16）, b = 10.868（2）, c = 12.970（3） A, α= 110.542（2）, β= 98.142（2）, γ= 99.766（2）°, V = 947.7（3） A3, Z = 4, F（000） = 400, Dc = 1.333 g/cm3, μ = 0.095 mm-1, the final R = 0.0550 and wR = 0.1483 for 2956 observed reflections with I〉 2σ（1）. Compound 7 （C13HI9N302, Mr = 249.31） crystallizes in the monoclinic system, space group C2/e with a = 18.926（3）, b = 12.1853（17）, e = 14.740（2） A, fl = 125.6380（10）~, V= 2762.7（7） A3, Z = 8, F（000） = 1072, Dc = 1.199 g/cm3,μ = 0.083 mm-1, the final R = 0.0554 and wR = 0.1468 for 2395 observed reflections with I 〉 2σ（I）. The preliminary bioassay results indicate that compound 6 exhibits notable fungicidal activities against Fusarium graminearum, Botrytis cinerea, Rhizoctonia cerealis and Colletotrichum capsici at the concentration of 100 μg/mL.

Regioselective Synthesis, Crystal Structure and Biological Activity of Novel 2-Phenylsulfonylhydrazono-3-(3-trifluoromethylphenyl)-2(3H)-thiazoline Derivatives

The title compounds 2-phenylsulfonylhydrazono-3-（3-trifluoromethylphenyl）-2（3H）- thiazoline derivatives were designed and synthesized via the reaction of thiosemicarbazides with chloroacetaldehyde, and their chemical structures were characterized by ^1H NMR, ^13C NMR, elemental analysis and MS. Furthermore, 4a was characterized by single-crystal X-ray diffraction. The target compound 4a （C16H12F3N302S2, Mr = 399.41） crystallized in monoclinic system, P21/c space group with a = 7.7457（4）, b = 13.5850（7）, c = 16.5455（10） A, β= 99.698（2）°, V= 1656.30（16） A3, Dc = 1.602 g/cm^3, Z = 4, F（000） = 816, λ = 0.71070 A,μ（MoKa） = 0.370 mm^-1, R = 0.072 and wR = 0.0867. The crystal structure of 4a revealed the cyclization of thiosemicarbazide moiety with chloroacetaldehyde at the N（l） position. The title compounds exhibited good insecticidal activity against spider mite （Tetranychus cinnabarinus Boisduval） and favorable fungicidal activity against Corynespora cassiicola.

Bactericidal and Fungicidal Efficacy of Chlorine Dioxide in Various Workspaces

Previously, we demonstrated the virucidal efficacy of low concentration chlorine dioxide (ClO2) gas in room settings. The purpose of these studies was to evaluate novel ClO2 formats as potential biocidal interventions for real world congregate settings and air systems. Three types of studies were conducted to determine the efficacy of ClO2 in reducing bacteria and mold in various workspaces: hard and soft surfaces (gymnasium & equipment), aerosol (in-room), and within a laboratory environment. The study demonstrated that ClO2 was highly effective against both bacteria and mold with reduction ranging from 85.0% - > 99.4% for bacteria and >99.4% for yeast and mold. Treatments on hard and soft surfaces (gymnasiums and sports equipment), reduced bacteria by an average of 90% - 95%. The following treatments were applied overnight: 1) hard surface spraying with dilute ClO2 solutions, 2) carpet and tumbling treatments with powdered ClO2 releasing impregnates, and 3) HVAC treatment and overall room deodorization with low dose ClO2 gas from controlled releasing sachets. The in-room study treating air with a ClO2 filtration media also indicated significant air and surface room efficacy, with an average of 94% reduction in bacteria after 24-hour, and 99.4% reduction in mold after 24-hours. In a related air study, a biological combination of Raoultella terrigena and Staphylococcus aureus was injected as a bio-aerosol into a 4-inch diameter pipe with air flowing at approximately 1200 ft/min. Dry ClO2 gas was introduced into the air flow to achieve an effective concentration of 5 or 10 ppmv. Air samples were collected at sampling ports downstream from the fan at 10, 22, 55 and 100 ft along the pipe and used to evaluate changes in airborne bacteria and mold. Testing was conducted in a laboratory setting at ambient conditions. The data showed ClO2 gas reduced viable organisms at both gas concentrations, and indicated that reductions were higher for 10 ppmv concentration, and longer pipe runs. In a final study, laboratory application of gaseous chlorine dioxide was tested. Low gas release filter testing demonstrated significant surface reductions of airborne bacteria with an overall average 99.4% reduction in the 24-hour testing period. Higher gas treatments of a class II biological cabinet reduced bacillus spores on steel coupons throughout cabinet by 6 log. ClO2 was effective as a bactericidal and fungicidal treatment providing significant reduction in both surface and air. Novel product delivery forms may be useful for rapidly disinfecting air and solid surfaces in complex congregate settings.

Synthesis,Crystal Structure and Antifungal Activity of 4-(5-((2,4-Dichlorobenzyl)thio)-4-phenyl-4H-1,2,4-triazol-3-yl)pyridine

The title compound 4-（5-（（2,4-dichlorobenzyl）thio）-4-phenyl-4H-1,2,4-triazol-3- yl）pyridine （C20HI4CI2N4S） was synthesized, and its structure was confirmed by 1H NMR, MS, elemental analyses and X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c with a = 14.885（5）, b = 8.597（2）, c = 16.144（5）A,β= 114.505（4）°, V= 1879.8（10） A3, Z= 8 and R = 0.0320 for 3108 observed reflections with I 〉 2σ（I）. The preliminary biological test shows that the title compound has activities against Stemphylium lyeopersici （Enjoji） Yamamoto, Fusarium oxysporum, sp. cueumebrium, and Botrytis cinerea with inhibitory to be 53.57%, 66.67% and 24.44%, respectively.

Synthesis, Crystal Structure, Docking and Antifungal Activity of a New Pyrazole Acylurea Compound

The title compound N-（（3,5-dimethylphenyl）carbamoyl）-1-methyl-3-（trifluoromethyl）-1 H-pyrazole-4-carboxamide（C（15）H（15）F3N4O2） was synthesized, and its structure was confirmed by 1 H NMR, H RMS and X-ray diffraction. It crystallizes in the triclinic system, space group P1 with a = 11.7147（5）, b = 11.7935（5）, c = 13.6620（5） A, α = 69.755（7）°, β = 66.182（6）°, γ = 72.100（7）°, Dc = 1.423 g/cm^3, Z = 4, V = 1588.88（11） A^3, the final R = 0.0347 and wR = 0.1005 for 7171 observed reflections with I 〉 2σ（I）. The preliminary biological test showed that the title compound has antifungal activities against Fusarium oxysporum, Pseudomonas syringae, Corynespora mazei and Botrytis cinerea at 100 μg/mL as 5.19%, 53.50%, 88.55% and 70.62%, respectively. The docking results indicated the hydrogen bonds formed between the compound and SHD.

Essential Oil from Inula britannica Extraction with SF-CO_2 and Its Antifungal Activity

The aim of this study was to determine the extraction technique of supercritical fluid carbon dioxide（SF-CO 2） for the essential oil from Inula britannica flowers and its antifungal activities against plant pathogenic fungi for its potential application as botanical fungicide.The effects of factors,including extraction temperature,extraction pressure,SF-CO 2 flow rate,flower powder size,and time on the essential oil yield were studied using the single factor experiment.An orthogonal experiment was conducted to determine the best operating conditions for the maximum extraction oil yield.Adopting the optimum conditions,the maximum yield reached 10.01% at 40°C temperature,30 MPa pressure,60 mesh flower powder size,20 L h-1SF-CO 2 flow rate,and 90 min extraction time.The antifungal activities of I.britannica essential oil using the SF-CO 2 against the most important plant pathogenic fungi were also examined through in vitro and in vivo tests.Sixteen plant pathogenic fungi were inhibited to varying degrees at 1 mg mL-1concentration of the essential oil.The mycelial growth of Gaeumannomyces graminis var.tritici was completely inhibited.The radial growths of Phytophthora capsici and Fusarium monilifome were also inhibited by 83.76 and 64.69%,respectively.In addition,the essential oil can inhibit the spore germination of Fusarium oxysporum f.sp.vasinfectum,Phytophthora capsici,Colletotrichum orbiculare,and Pyricularia grisea,and the corresponding inhibition rates were 98.26,96.54,87.89,and 87.35% respectively.The present study has demonstrated that the essential oil of I.britannica flowers extracted through the SF-CO 2 technique is one potential and promising antifungal agent that can be used as botanical fungicide to protect crops.