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1.
This study was undertaken to determine the antibacterial efficacy of the leaves extracts of Lawsonia inermis in vitro and in vivo, against the phytopathogenic bacteria Pseudomonas savastanoi pv savastanoi IVIA 1628 and Agrobacterium tumefaciens. The hydroalcoholic extract of L. inermis was fractionated by liquid–liquid partition using hexane, chloroform, ethyl acetate and butanol. Among the tested fractions, the ethyl acetate (EtOAcF) and chloroform (CHCl3F) extracts exhibited high inhibition against all tested plant pathogens. The extracts exerted a bactericidal activity against both P. savastanoi and A. tumefaciens with MIC values ranging from 1.25 to 2.5 mg/ml. In planta experiments, the EtOAcF, tested at four concentrations (0.4, 0.2, 0.1 and 0.05 mg/wounds), completely inhibited the formation of knots on twigs of olive and tomato plants inoculated with pathogenic strains of P. savastanoi and A. tumefaciens (strains B6 and C58). The phytochemical screening revealed that the L. inermis fractions contain flavonoids, quinones, tannins and terpenoids. The qualitative analysis of the EtOAcF by LC–DAD–ELSD–ESI/MSn showed the presence of eight identified phenolic and phenolic glycoside compounds. These results suggest that L. inermis extracts could be used to control plant bacterial diseases caused by P. savastanoi and A. tumefaciens.  相似文献   

2.
The resistance to bismerthiazol in the Xanthomonas oryzae pv. oryzae population in China has not been clearly determined. Three bismerthiazol-resistant mutants (1-1-1, 2-1-1, 4-1-1) of X. oryzae pv. oryzae were induced on rice plants and the characteristics were compared with their parental strain ZJ173. After 10 subcultures on fresh bismerthiazol-free nutrient agar plates and after being inoculation onto and re-isolation from untreated rice plants two times, the mutants remained pathogenicity on rice plants treated with 300 μg/ml bismerthiazol, indicating that the in vivo-induced bismerthiazol resistance was stable in vivo. The in vitro characteristics of the bismerthiazol-resistant mutants and a wild-type bismerthiazol-sensitive strain (ZJ173) were also compared. The three mutants grew faster than ZJ173 during the logarithmic growth phase but at the same rate during the decline phase. Bismerthiazol had protective and curative activity against strain ZJ173 but not against the three mutants. To evaluate the current degree of bismerthiazol resistance in field populations of X. oryzae pv. oryzae in China, 781 isolates of X. oryzae pv. oryzae were obtained from 1419 leaf samples collected from Yunnan, Sichuan, Jiangsu, Anhui, Hubei, Guangdong, Hainan, and Hunan Provinces in China from 2007 to 2009. The in vivo sensitivity of 505 of the 781 isolates to bismerthiazol was determined by applying them to rice plants treated with 300 μg/ml bismerthiazol and evaluating blast severity. The tested strains were considered resistant, if they showed <70% inhibition relative to strain ZJ173. Of the 505 isolates, 62 were resistant to bismerthiazol. The resistance frequencies among field population ranged from 0 to 21.1%, differed among the provinces, and was 11.2, 20.0 and 10.4% in 2007, 2008 and 2009, respectively. Resistance determined in vivo was not related to resistance determined in vitro. The in vivo-induced bismerthiazol resistance identified in this study will serve as a base line for further studying bismerthiazol resistance in fields, and the current degree of bismerthiazol resistance in field populations of X. oryzae pv. oryzae in China determined would be useful for the rice growers for control of rice bacterial blight.  相似文献   

3.
The present study aimed to determine the in vitro and in vivo effects of Ziziphora clinopodioides Lam. essential oil (ZCEO) against Sclerotinia sclerotiorum on rapeseed plants. Gas chromatography-mass spectrometry (GC-MS) detected 21 compounds that represented 98.3% of the total amount of extracted oil, which mainly comprised pulegone (53.5%), isomenthone (10.4%), and carvone (5.7%). The mycelial growth of S. sclerotiorum was completely inhibited at essential oil concentrations of 1.25 and 0.15 μl ml−1 under contact and vapor phase conditions, respectively. Under contact phase, the germination of sclerotial was inhibited at the concentration of 1.00 μl ml−1. The essential oil concentration of 0.15 μl ml−1 in the vapor phase showed a strong inhibitory effect on sclerotial germination. Sclerotinia sclerotiorum growth on detached rapeseed leaves and potted rapeseed plants were dose dependently inhibited by the essential oil. Considerable morphological changes were also observed in the fungal hyphae and sclerotia. Both in vitro and in vivo results indicated ZCEO can effectively inhibit the growth of S. sclerotiorum. Thus, ZCEO could be used for crop protection.  相似文献   

4.
Microorganisms such as fungi are one of the most important factors that cause oxidative processes during postharvest stage and consequently deterioration of agriculture products would not be unexpected. On the other hand, high antioxidant properties of industrial by-products of pomegranate propose them as powerful antioxidant and antifungal substances. So to investigate the antioxidant and antifungal properties of pomegranate, two independent factorial experiments based on randomized design with 5 replications were conducted. In the first experiment the effect of 3 different parts of pomegranate (peel, seed and leaf) and 2 different kinds of extracts (aqueous and methanolic) with 4 concentrations (0, 500, 1000 and 1500 ppm) were investigated on 3 postharvest fungi (Penicillium italicum, Rhizopus stolonifer and Botrytis cinerea). In the second experiment antioxidant capacity and phenolic content were measured for two different extracts from different parts. Based on the results the methanolic extract showed the highest inhibitory effects on the mycelia growth (IMG) and spore germination (ISG) with 49.82 and 41.25% respectively. On the other hand, peel and seed extracts had more inhibitory effect (IMG and ISG) than leaf extract. The phenolic content of peel extract were also measured 2.8 fold higher than pomegranate leaf extract and antioxidant capacity of peel, seed and leaf extracts of pomegranate were 55.3%, 35.7% and 16.4% respectively. Therefore, it seems that the high percentage of phenolic content in the peel and seed of pomegranate could cause the high antifungal and antioxidant activity of their extracts.  相似文献   

5.
Compost teas are fermented extracts of composted materials that are used to control plant diseases. A compost extractor in liquid phase, with forced air blowing system and assembled using farmer facilities, was used to produce “on farm” aerated compost teas (CTs) from five types of compost, in a 14-day fermentation cycle. Solid feed stocks, including one biowaste compost and four composted tomato residues, were extracted in water (waCTs) and whey (whCTs), separately. The ten teas showed high biological control ability, both in vitro and in vivo, against three tomato pathogens: Alternaria alternata, Botrytis cinerea and Pyrenochaeta lycopersici. In in vitro trials, the suppressive ability of raw CTs was lost with sterilization, suggesting an antibiotic-like antagonism effect due to active microorganisms in suspension. Direct application of teas on tomato plants significantly reduced disease symptoms caused by tested pathogens. In vivo suppressiveness was more significant using the liquid phase fermentation (whey or water) than the compost. Whey could be considered a viable extractant for suppressive compost-tea production, although further dilution in dechlorinated water at a ratio of at least 1:5 proved a necessary method to avoid occurrence of root or foliar phytotoxicity, probably due to high salt concentrations and sub-acid pH of the relative teas.  相似文献   

6.
Bacterial spot of tomato (Solanum lycopersicum) caused by Xanthomonas campestris pv. vesicatoria (Xcv) is a devastating disease of tomato world-wide. In the southeastern United States, high summer temperatures and humidity are ideal conditions for this disease, resulting in defoliation, fruit spotting and a significant reduction in fruit yield. Current organic production practices restrict the use of synthetic chemicals for disease control; hence, there is a need for the development of new and effective biopesticides to mitigate plant diseases. Among several biological agents with potential for disease control, Lentinula edodes (shiitake mushroom) has been shown to have antibacterial properties. A controlled-environment study was therefore conducted to validate L. edodes mycelia culture filtrate (Lemcf) foliar application to control bacterial spot of tomato using the cultivar Agriset 761. Lentinula edodes mycelia culture filtrate foliar spray significantly suppressed bacterial spot incidence in tomato foliage in vitro but was not effective in vivo. The phytotoxicity symptoms in Lemcf-treated tomato foliage were attributed to the presence of 422.78 μg of oxalic acid per milliliter of Lemcf (quantified by high-pressure liquid chromatography). Plant height and flowering were normal in Lemcf-treated plants. Additionally, Lemcf seed treatment did not adversely impact tomato germination but significantly enhanced the germination of marginal tomato seeds subjected to biotic stress (Xcv). Our results suggest that after eliminating oxalic acid from Lemcf, the product may be a potential biopesticide for managing bacterial spot of tomato. Future greenhouse or field experiments should be conducted after eliminating oxalic acid from L. edodes culture filtrates.  相似文献   

7.
Environmentally friendly control measures are needed for soilborne diseases of crops grown in organic and conventional production systems. We tested ethanol extracts from cultures of Serratia marcescens N4-5 and N2-4, Burkholderia cepacia BC-1 and BC-2, and Burkholderia ambifaria BC-F for control of damping-off of cucumber caused by the soilborne pathogens Pythium ultimum and Rhizoctonia solani; ethanol being an Organic Materials Review Institute (OMRI) -approved solvent for use in certain applications in organic crop production. Ethanol extracts from strains N4-5 and N2-4 inhibited mycelial growth and germination of sporangia of P. ultimum in vitro but those from strains BC-1, BC-2, BC-F, and the ethanol control did not. Ethanol extracts from strains BC-2 and BC-F inhibited mycelial growth of R. solani in vitro while ethanol extracts from strains BC-1, N2-4, N4-5, and the ethanol control did not. Thin-layer chromatography demonstrated that ethanol extracts from strain N4-5 contained prodigiosin while ethanol extracts from strains BC-2 and BC-F contained pyrrolnitrin; extracts from strains N2-4 and BC-1 did not contain either of these compounds. DNA sequencing confirmed the presence of a biosynthetic gene for prodigiosin in strain N4-5 and its absence in strain N2-4, while a biosynthetic gene for pyrrolnitrin was found in strains BC-2 and BC-F but not in strains N2-4, N4-5, and BC-1. Prodigiosin was previously implicated in inhibition of P. ultimum while pyrrolnitrin has been shown to inhibit R. solani. Certified-organic cucumber seed treated with an ethanol extract of strain N4-5 was the only extract treatment from any of these five microbial strains to effectively suppress damping-off caused by P. ultimum in growth chamber pot experiments. This ethanol extract provided suppression of P. ultimum on cucumber that was similar to that provided by a commercially available seed treatment pesticide and greater than that provided by a commercially available biocontrol agent for this pathogen. The inhibitory factor(s) in ethanol extracts of strain N4-5 was stable as a seed treatment for at least 14 weeks when incubated at 4 °C in the dark. No ethanol extracts applied as treatments of organic cucumber seed consistently suppressed damping-off caused by R. solani in growth chamber pot experiments. Experiments reported here suggest that certain natural products from microbial strains as seed treatments are promising alternatives for control of soilborne diseases in conventional or organic cucumber production systems.  相似文献   

8.
The effect of chitosan treatment alone or in combination with methyl jasmonate (MeJA) against Alternaria alternata in vitro and in vivo, and defense related enzyme activities were investigated. 100–500 μl/l MeJA significantly inhibited mycelial growth of A. alternata. The inhibitory activity of MeJA on mycelial growth, spore production, spore germination and germ tube length of A. alternata in vitro could be enhanced by 0.1% chitosan. The combination of 0.1% chitosan and 500 μl/l methyl jasmonate was more effective to reduce the disease incidence and lesion diameter of postharvest decay of cherry tomato than the application of MeJA or chitosan alone. The combined treatments resulted in higher activities of PPO (polyphenol oxidase), POD (peroxidase) and PAL (phenylalanine ammonialyase) than the control. This work indicated that the combination of chitosan and methyl jasmonate is a promising method to control postharvest decays of fruit and vegetables.  相似文献   

9.
Chitosan is capable of triggering the induction of defence responses of the plants. This study was carried out to investigate in vitro and in vivo antifungal activity of submicron chitosan dispersions and also to determine the mechanism of induced resistance in dragon fruit plants by strengthening of cell wall and production of pathogenesis related proteins. Highest inhibition in radial mycelial growth (90.2%) was obtained by 600 nm droplet size at 1.0% chitosan concentration. None of the emulsifiers showed any antifungal effect during in vitro studies. Field studies showed the reduction of 22% disease incidence and 66% disease severity in anthracnose on dragon fruit plants treated with 600 nm droplet size as compared to control plants after one month of assessment. Lignin contents in cell wall of dragon fruit plants increased 2 folds in plants treated with 1.0% chitosan at 600 nm droplet size while 11 and 10 folds increase in β-1,3-glucanase and chitinase activity, respectively was also recorded in the plants inoculated with Colletotrichum gloeosporioides. The accumulation of lignin and higher level activity of pathogenesis related proteins in response to submicron chitosan dispersions may bolster in mounting effective resistance against the devastating disease of anthracnose.  相似文献   

10.
With recent public attention focused on chemical residues in food, the managing of plant disease organisms without the use of conventional chemical fungicides or bactericides can sometimes be a challenge. The main aim of this study was the evaluation of the antifungal activity of the essential oils of Ocimum basilicum, Origanum vulgare, Rosmarinus officinalis, Rosmarinus officinalis ‘Prostrates’, Salvia officinalis and their major constituents (carvacrol, thymol, linalool, eucalyptol) against the fungus Pilidiella granati. The results showed that the essential oil vapour of O. basilicum, S. officinalis, R. officinalis, Rosmarinus officinalis ‘Prostrates’, O. vulgare had fungicidal activities against the mycelial growth and conidia germination of P. granati, the pathogen causing postharvest fruit rots in pomegranate. However, in vivo experiments, only the essential oils of O. vulgare and O. basilicum controlled this fungus effectively with the essential oil of O. vulgare to being more effective at the same rates. Analysis showed a high number of compounds in each essential oil, with carvacrol, eucalyptol, linalool and thymol predominating. Thymol and carvacrol primarily and linalool secondary showed antifungicidal activity against P. granati. These results represent an important step towards the goal using essential oils from O. basilicum, S. officinalis, R. officinalis, R. officinalis ‘Prostrates”, O. vulgare and their constituents carvacrol and thymol to control of the pathogen P. granati of pomegranate.  相似文献   

11.
Extracts obtained from liquid mycelial fermentations of Chilean species of the Stereum genus showed antifungal activity against Botrytis cinerea. Thirty-six strains were evaluated in vivo and in vitro assays, 25 belonging to Stereum hirsutum (Sh) and 11 to Stereum rameale (Sr). Two types of extracts were obtained: EtOAc-extract (liquid phase) and MeOH-extract (mycelial phase). Plate diffusion assay showed that EtOAc-extracts were more active than MeOH-extracts. S. hirsutum included 4 strains with the highest antifungal activity (Sh134-11, Sh144-11, Sh152-11, Sh155-11) and S. rameale highlighted with two strains (Sr25-11, Sr27-11). Effects on the mycelial growth of B. cinerea showed that EtOAc-extracts produced by S. hirsutum (Sh134-11, Sh152-11) inhibited from 1000 μg mL−1, reaching 67 and 49%, respectively. At 2000 μg mL−1, these strains inhibited nearly 80% of mycelial growth. EtOAc-extract of Sh134-11 was more effective to control the sporogenesis, inhibiting in 100% the sporulation at 500 μg mL−1. Assays showed that Sh134-11 and Sh152-11 exhibited a minimal fungicidal concentration (MFC) of 50 and 100 μg mL−1 respectively and minimal inhibitory concentration (MIC) at 20 μg mL−1. EtOAc-extracts of Sr25-11 and Sr27-11 showed MFC value at 100 μg mL−1 and MIC at 20 and 50 μg mL−1, respectively. Strawberries treated with 1000 μg mL−1of Sh134-11 and Sr25-11 reached 82 and 72% of decay inhibition, respectively. Treatments with 2000 μg mL−1 showed a decay inhibition of 90% approximately. In vivo tests are in accordance with the results obtained in vitro assays, confirming the efficacy of Sh134-11 and Sr25-11 to control B. cinerea. Differences in antifungal activities observed in the different strains suggested that the ability to produce bioactive compounds is not homogenously distributed among S. hirsutum and S. rameale. Our study would suggest that submerged fermentations of Chilean S. hirsutum strain Sh134-11 produce extracts, which could be used as possible biofungicides and an alternative to synthetic fungicides.  相似文献   

12.
The bioactivity of compounds produced by Pseudomonas aeruginosa (LN strain), against three Xanthomonas species was investigated under greenhouse conditions and using electron microscopy. Chromatographic fractions EAP, VLC3, VLC4, VLC3d and VLC4f were tested against Xanthomonas axonopodis pv. malvacearum, X. axonopodis pv. phaseoli and X. axonopodis pv. citri by disc diffusion. Fractions with antibiotic activity were tested in vivo under greenhouse conditions and their bioactivity was evaluated. Scanning electron microscopy showed that VLC4f affects biofilm formation while VLC4f and VLC3d both affect cell morphology. The semi-purified fractions controlled bacterial diseases caused by Xanthomonas spp. when sprayed on plants under greenhouse conditions. The VLC4f fraction showed superior results in disease management, reducing the number of lesions on cotton and orange leaves by 94%, and reducing disease severity in bean leaves by 73%. The data suggest that the fractions were effective and have potential as an alternative to conventional bactericides in the control of plant diseases caused by Xanthomonas sp under greenhouse conditions.  相似文献   

13.
Antioxidants are compounds responsible for free radical scavenging in the body. They protect the organism from oxidative modification of cells and tissues. These modifications have been associated with degenerative diseases, atherosclerosis and carcinogenesis. Punica granatum displays high antioxidant potential due to the presence of phenolic compounds, which are capable of disease prevention. The present study showed the highest antioxidant activity in pomegranate peel than in seeds and pulp. Based on these results, pomegranate peel was used to produce dried extract that was added to commercial tomato juice and orange juice with strawberries. Analysis to determine the content of phenolic compounds and antioxidant activity was performed on pomegranate pulp, seeds and peel and in juices enriched with dried extract of pomegranate peel. The dried extract was responsible for a significant increase in antioxidant activity of the juices, proportional to the concentrations added. However, although both flavors of enriched juices displayed high antioxidant levels, the samples with higher dried extract concentrations received the lowest scores from sensory analysis participants due to the characteristic astringent flavor of pomegranate peels. Therefore, to obtain greater acceptance in the consumer market, we concluded that the maximum addition of dried pomegranate peel extract is 0.5% in tomato juice and orange juice with strawberries.  相似文献   

14.
Vitex agnus-castus methanolic extract showed strong antifungal activity against Pythium ultimum in tomato under both in vitro and in vivo conditions. The 0.2% extract delayed the mycelial growth of the fungus and showed significant antifungal activity against P. ultimum on tomato seedlings with an efficacy comparable to that of the synthetic fungicide. To determine the involvement both of plant extract and pathogenic fungus in PR gene induction, tomato plants were treated with V. agnus-castus extract and/or inoculated with P. ultimum. The expression of four PR genes (PR-1, PR-2, PR-5, PR-6) was monitored at five time points within 48 h of the extract treatment and fungal inoculation. The PR-1 and PR-4 genes were activated directly by V. agnus-castus extract up to 12 h after treatments; at 24 h, the direct activation by plant extract disappeared and a synergistic inducing effect of extract and pathogen applied simultaneously on the plant was observed. The PR-6 gene was not activated directly by the V. agnus-castus extract but only when applied together with the pathogen; activation of the PR-6 gene occurred 24 h after treatments and the gene expression increased at 48 h. There was no activation of PR-5 gene by the plant extract. The ability of V. agnus-castus extract to enhance plant defence responses upon pathogen inoculation might be further investigated. The activation of various PR genes suggests that induction of defence responses by V. agnus-castus extract in tomato may be regulated by more than one signalling pathway.  相似文献   

15.
Postharvest peach fruit are susceptible to fungal decay. To search for effective alternatives to currently used fungicides for disease control, the in vitro and in vivo antifungal activities of tea polyphenol (TP) and tea saponin (TS) individually or their combination were evaluated against Monilinia fructicola isolated from infected nectarine fruit in this study. The in vitro experiments showed that both TP and TS inhibited the mycelial growth in a dose-dependent manner and their combination exhibited an additive or synergistic antifungal interaction with the cotoxicity factor (CTF) exceeding −20. The in vivo experiments showed that they both effectively controlled brown rot on inoculated nectarine fruit and their combination (TP: TS, 1:2) significantly improved the controlling effect. Our results also revealed that TP and TS induced the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenoloxidase (PPO), chitinase and β-1,3-glucanase in inoculated nectarine fruit and their combination strengthened the induction. These findings suggested that the combination of TP and TS could effectively control brown rot on postharvest fruit and that the mechanism of the control might be attributed to the induction of defensive enzyme activities.  相似文献   

16.
Kafirins have been extracted from several types of sorghums due to their potential use for production of gluten-free products. Nevertheless, the extraction of these proteins from wet-milled sorghum gluten meal (SGM) has not yet been explored. In this study, we investigated the differences in composition, color, molecular structures, functionality and in vitro protein digestibility of kafirin extracts obtained from dry-milled flour or SGM obtained from decorticated white sorghum treated with and without endopeptidic protease. Kafirins were extracted using aqueous ethanol and metabisulfite. Kafirin extracts from SGM presented higher protein purity (95% vs 86%), lower fat content (0.7% vs 2.0%), in vitro protein digestibility (89% vs 85%), and better water holding (2.8 vs 1.9 g/g) and fat absorption capacities (2.4 vs 1.6 g/g) compared to extracts from ground decorticated sorghum. Color was not affected by treatments. SDS-PAGE showed differences in the low molecular weight patterns of kafirin extracts obtained from SGM whereas FTIR analyses showed reduction of α-helical and β-turn percentages and β-sheet increment after extraction. The proposed protease treatment increased free amino nitrogen and emulsifying index of kafirins, but did not affect other functional properties. Thus, SGM represents a potential new feedstock for the extraction of food-grade kafirins.  相似文献   

17.
Mechanisms of action and effectiveness of the antifungal yeast Cryptococcus laurentii [(Kuff.) C.E. Skinner] strain L5D, were examined against the causal agent of anthracnose Colletotrichum gloeosporioides ((Penz.) Penz. & Sacc.) in mango (Mangifera indica L.). C. laurentii showed a high antagonistic potential in vivo, with significant inhibition of anthracnose (75.88%). Different mechanisms of action were examined in C. laurentii among them competition for nutrients, specifically for sucrose (p < 0.05). Scanning Electron Microscopy (SEM) showed that the yeast biofilm adheres to the fruit and to C. gloeosporioides hyphae showing competition for space; C. laurentii was not washed off from treated Colletotrichum hyphae as observed with SEM. According to statistical analysis, only nagase and chitinase were significantly stimulated on wounded fruit. Activity of all three hydrolytic enzymes was detected in vitro but only nagase was induced by addition of autoclaved pathogen mycelium. Treated wounds with the yeast biocontrol stimulated glucanase activity and suppressed chitinase activity on fruit wounds with or without presence of autoclaved pathogen mycelium but did not affect nagase significantly (p = 0.05). Parasitic activity of yeast on pathogen was not detected.  相似文献   

18.
The antifungal activity of steam-exploded liquid waste (SELW) produced by the detoxification of steam-exploded biomass of Miscanthus sinensis, Arundo donax and wheat straw for 2nd generation industrial bioethanol production was studied against plant pathogenic fungi for the first time. Quantification of fermentation inhibitors (2-furaldehyde, 5-hydroxymethylfurfural, acetic and formic acid) was carried out by standard methods. Mycelial growth inhibition and conidial germination of eight fungal strains [Alternaria alternata, Botrytis cinerea, Colletotrichum acutatum, Cladosporium fulvum, Fusarium oxysporum f. sp. lycopersici (FOL), F. oxysporum f. sp. melonis (FOM), F. solani f. sp. pisi and Verticillium dahliae] were evaluated in vitro at different dilution rates (1:2, 1:4 and 1:8) for each SELW. Disease suppressiveness was assessed in vivo in eight horticultural pathosystems (A. alternata/tomato, B. cinerea/tomato, C. acutatum/strawberry, C. fulvum/tomato, FOL/tomato, FOM/melon, F. solani f. sp. pisi/pea and V. dahliae/eggplant) under greenhouse conditions. Pathogen suppression by each SELW, applied both in spray form on to tomato leaves and skins of tomato and strawberry, and by means of dipping method in watering suspensions on to seedling root systems of tomato, melon, pea and eggplant, was evaluated at dilution rates of 1:2, 1:4 and 1:8 using irrigation water during curative and preventive treatments. Investigations carried out in vitro showed that M. sinensis SELW was more suppressive than wheat straw SELW, and A. donax SELW was less suppressive than wheat straw SELW at the lowest dilution rates. Relationships between the concentration of 2-furaldehyde, acetic and formic acid present in SELWs and their antifungal effect were found. Moreover, B. cinerea, C. fulvum, V. dahliae, A. alternata, C. acutatum and F. solani f. sp. pisi were more effectively inhibited than FOL and FOM. Investigations performed in vivo showed that SELWs of M. sinensis and wheat straw can be diluted at a 1:2 rate and used for controlling six fungal diseases during preventive treatments. In particular, they can be used by dipping of the root systems during transplanting in the case of F. solani f. sp. pisi/pea and V. dahliae/eggplant; on the other hand, they can be nebulized on to the leaves and fruits before symptoms appearance in the case of A. alternata/tomato, B. cinerea/tomato, C. acutatum/strawberry and C. fulvum/tomato. This study is of particular interest because it points out how these SELWs could be employed in horticultural crop protection in Southern Italy, thereby making it possible to effectively combine industrial production of 2nd generation biofuels with sustainable horticulture under greenhouse conditions.  相似文献   

19.
Although kiwifruit is considered as a crop with few phytopathological problems, new diseases have been identified in the last few years. This study is the first report of a shoot blight and canker disease of kiwifruit in Greece caused by the fungus Diaporthe neotheicola. The fungal species was identified based on fungal morphology and the analyses of the nuclear rDNA internal transcribed spacer (ITS), and the translation elongation factor 1-alpha (TEF-1α) gene regions.The pathogen caused distinct cankers on shoots of kiwifruit, while pycnidia were observed on the blighted shoots. The rate of development of D. neotheicola in vitro was reduced as temperatures increased from 25 to 30 °C, decreased from 20 to 10 °C, and was totally inhibited at 35 and 2–4 °C. The rate of conidial germination and the length of germ tube in vitro were reduced as temperatures increased from 25 to 30 °C, decreased from 25 to 10 °C, and was totally inhibited at 35 and 2–4 °C. A preliminary study on the effectiveness of the fungicides thiophanate methyl, carbendazim and tebuconazole against the development and germination of conidia of D. neotheicola and the disease symptoms was conducted. All fungicides were effective against the fungus in vitro. In addition, no canker was observed on artificially inoculated shoots treated with the fungicides. In general, the disease could be a threat for kiwifruit in Greece and its management should be investigated in the field.  相似文献   

20.
So far, data on absorption and metabolism of steryl ferulates from edible sources is scarce. Therefore, the impact of enzyme-aided baking and in vitro digestion was examined in this study. Wheat flours and wheat breads were subjected to a static in vitro digestion model and changes in the contents of steryl ferulates and free sterols (possible hydrolysis products of steryl ferulates) were monitored. Baking degraded steryl ferulates at a similar rate in all types of breads (43–47%) compared to the corresponding flours, while baking induced changes in free sterols showed no clear pattern. In vitro digestion provoked five folds lower content of steryl ferulates in flours than in breads and it also resulted in significant free sterol accumulation. Interestingly, bioaccessibility (0.01–0.25%) was not influenced by the cereal matrix. The four steryl ferulate species, which were detected in wheat, showed similar hydrolysis rates during digestion. As baking had a significant impact on the steryl ferulate content of wheat, we suggest that both raw and processed sources should be considered further in vitro, animal or human trials, when studying the metabolic fate of steryl ferulates.  相似文献   

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