Journal of Environmental Science and Health, Part B, 2020
Twenty-two strains of Trichoderma spp. (T. harzianum species complex [THSC], Trichoderma aggressi... more Twenty-two strains of Trichoderma spp. (T. harzianum species complex [THSC], Trichoderma aggressivum f. europaeum, Trichoderma pleuroti, and Trichoderma pleuroticola) causing green mold disease on edible mushrooms (button mushroom, shiitake and oyster mushroom), collected during 2004-2018 from four countries (Serbia, North Macedonia, Croatia, and Hungary) were examined. Based on their ITS (internal transcribed spacer) sequences, strains from shiitake mushroom in Serbia were identified as members of the THSC, while in samples obtained from Serbian and North-Macedonian oyster mushroom farms THSC, T. pleuroti and T. pleuroticola were detected, which represent the first findings in the region. In fungicide susceptibility tests, all examined Trichoderma strains were found to be highly sensitive to prochloraz (ED 50 <0.4 mg mL À1) and considerably susceptible to metrafenone (ED 50 < 4 mg mL À1). The most sensitive taxon to both fungicides was THSC from oyster mushroom. The toxicity of metrafenone was satisfying and strains from oyster mushroom showed the highest sensitivity (ED 50 < 1.43 mg mL À1), while strains originating from button mushroom and shiitake displayed similar susceptibilities (ED 50 < 3.64 mg mL À1). After additional in vivo trials, metrafenone might also be recommended for the control of green mold disease in mushroom farms.
Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. c... more Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. campestris pv. phaseoli, the causal agent of common blight of beans, following leaf-spray inoculation with bacterial suspension (108 cfu/ml). The plants were evaluated based on the number of leaf lesions, and the disease severity index (DSI) was calculated. The evaluated genotypes showed various levels of susceptibility to X. campestris pv. phaseoli strain VS-1. The results of both experiments showed that the cultivar Oreol was the most resistant. The genotypes: KB 142, HR-45, Tisa and Panonski tetovac also showed low susceptibility with DSI values in the first trial ranging from 2.27 to 3.60. The same genotypes, with the exception of Panonski tetovac, were also categorized as low-susceptible to the bacterium in the second experiment, having the DSI values between 2.27 and 3.60. Most genotypes (Slavonski žutozeleni, Zlatko, Biser, Sremac, Naya Nayahit) were categorized as susceptible in t...
Cladobotryum dendroides is the most frequently found soil-borne mushroom pathogen in Serbia [1]. ... more Cladobotryum dendroides is the most frequently found soil-borne mushroom pathogen in Serbia [1]. Although many investigations have been carried out to find an adequate disinfectant of mushroom casing, so far, none has been found to be completely effective thus non-toxic to humans. The aim of this study was to explore the potential of Ecocute, based on colloidal silver [2-3] and Peral-S (active oxygen) [4-5], as environmentally friendly casing disinfectants. Efficacies of the disinfectants and incidence of cobweb disease were evaluated in bags of compost cased with a black peat/lime casing soil, previously disinfected with Ecocute at 30 mg L -1 per m 2 and Peral-S at 1.7 ml L -1 per m 2 . Plots were inoculated with suspension set on 1000 conidia per m 2 of C. dendroides. Both disinfectants were applied alone and in combination with prochloraz-manganese. Biological efficiency of colloidal silver applied alone was higher than in treatments with active oxygen in all trials. The colloida...
... in vitro BrankicaTanovic, Svetlana Milijasevic, Biljana Todorovic, Ivana Potocnik i Emil Reka... more ... in vitro BrankicaTanovic, Svetlana Milijasevic, Biljana Todorovic, Ivana Potocnik i Emil Rekanovic Institut "Sròija", Centar za pesticide i zastitu zivotne sredine, Beograd-Zemun REZIME Prouceno je delovanje gasovite faze etarskih ulja standardnog kvaliteta 18 vrsta bil-jaka ...
Several methods used for the detection of Clavibacter michiganensis subsp. michiganensis (Cmm) in... more Several methods used for the detection of Clavibacter michiganensis subsp. michiganensis (Cmm) in artificially infested tomato seed lots were evaluated using two seed extraction methods (grinding and soaking). The detection threshold was evaluated by adding different numbers of artificially infested seeds (one, five and ten) to noninfected seed samples of two different sizes: 2000 and 5000 seeds. Four detection methods were simultaneously compared for their sensitivity in Cmm detection in seeds: isolation on selective media, direct PCR from seed material, Bio-PCR which first cultured bacteria on NBY agar prior to PCR, and Enrichment PCR. In samples of 2000 seeds containing one, five and ten infested seeds, the pathogen was detected in at least four out of five replicates by three detection methods (selective plating, direct PCR and Bio-PCR), using both the grinding extraction method (with an addition of centrifugation step) and soaking. DNA extraction from seed material was needed before the Enrichment PCR and direct PCR amplifications were performed. In samples of 5000 seeds one infested seed could not be detected by direct PCR or Enrichment PCR in any of the five replicates, regardless of the seed extraction method used. In samples containing five infested seeds per 5000 seeds, Cmm was detected by all four detection methods. A comparison of the efficiency of detection of the pathogen by using extraction methods that included grinding and soaking showed no differences between them.
Monitoring of button mushroom bacterial diseases was conducted to estimate the presence and ident... more Monitoring of button mushroom bacterial diseases was conducted to estimate the presence and identity of mycopathogenic bacteria and to determine the predominant bacterial pathogen in Serbia. Samples were collected from mushroom farms during 2006- 2010 and also from fresh markets during 2014-2015. The collected samples showed either symptoms of brown blotch or different degrees of brown discoloration on caps and stalks of Agaricus bisporus resembling bacterial infection. The presence of bacterial droplets on gills was not recorded. The isolated bacteria were Gram-negative and fluorescent on King?s medium B. In pathogenicity tests, most bacterial isolates induced superficial or sunken brown lesions with differences in the level of discoloration on A. bisporus tissue blocks after artificial inoculation. Based on LOPAT characteristics, the isolates were divided into two groups, showing characteristics of either the LOPAT group Va or group III. Based on these features and other different...
World Journal of Microbiology and Biotechnology, 2019
Lignocellulosic plant biomass is the world's most abundant carbon source and has consequently att... more Lignocellulosic plant biomass is the world's most abundant carbon source and has consequently attracted attention as a renewable resource for production of biofuels and commodity chemicals that could replace fossil resources. Due to its recalcitrant nature, it must be pretreated by chemical, physical or biological means prior to hydrolysis, introducing additional costs. In this paper, we tested the hypothesis that fungi which thrive on lignocellulosic material (straw, bark or soil) would be efficient in degrading untreated lignocellulose. Wheat straw was used as a model. We developed a fast and simple screening method for cellulase producers and tested one hundred Trichoderma strains isolated from wheat straw. The most potent strain-UB483FTG2/ TUCIM 4455, was isolated from substrate used for mushroom cultivation and was identified as T. guizhouense. After optimization of growth medium, high cellulase activity was already achieved after 72 h of fermentation on raw wheat straw, while the model cellulase overproducing strain T. reesei QM 9414 took 170 h and reached only 45% of the cellulase activity secreted by T. guizhouense. Maximum production levels were 1.1 U/mL (measured with CMC as cellulase substrate) and 0.7 U/mL (β-glucosidase assay). The T. guizhouense cellulase cocktail hydrolyzed raw wheat straw within 35 h. Our study shows that screening for fungi that successfully compete for special substrates in nature will lead to the isolation of strains with qualitatively and quantitatively superior enzymes needed for their digestion which could be used for industrial purposes.
In vitro antagonistic potential of eleven isolates of Bacillus spp. against two phytopathogenic b... more In vitro antagonistic potential of eleven isolates of Bacillus spp. against two phytopathogenic bacteria and one fungus was tested in order to identify potential biocontrol agents in vegetable crops. The Bacillus spp. isolates demonstrated different levels of antagonistic effect against the tested pathogenic microorganisms. Data in the study proved Xanthomonas vesicatoria to be more sensitive to Bacillus spp. strains than Clavibacter michiganensis subsp. michiganensis. Ten B. subtilis strains induced growth inhibition of X. vesicatoria, while a strain of B. pumilus did not affect the growth of that bacterium. The largest inhibition zones against X. vesicatoria were induced by strains B-319, B-325 and B-358. The pathogenic strain C. michiganensis subsp. michiganensis was most inhibited by two B. subtilis strains (B-338 and B-348) with mean inhibition zone diameters of up to 20 mm. B. subtilis strain B-319 which was the best in inhibiting X. vesicatoria, showed the lowest inhibitory e...
Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. c... more Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. campestris pv. phaseoli, the causal agent of common blight of beans, following leaf-spray inoculation with bacterial suspension (108 cfu/ml). The plants were evaluated based on the number of leaf lesions, and the disease severity index (DSI) was calculated. The evaluated genotypes showed various levels of susceptibility to X. campestris pv. phaseoli strain VS-1. The results of both experiments showed that the cultivar Oreol was the most resistant. The genotypes: KB 142, HR-45, Tisa and Panonski tetovac also showed low susceptibility with DSI values in the first trial ranging from 2.27 to 3.60. The same genotypes, with the exception of Panonski tetovac, were also categorized as low-susceptible to the bacterium in the second experiment, having the DSI values between 2.27 and 3.60. Most genotypes (Slavonski zutozeleni, Zlatko, Biser, Sremac, Naya Nayahit) were categorized as susceptible in t...
In order to control the causal agent of Verticillium wilt of pepper (Verticillium dahliae), the e... more In order to control the causal agent of Verticillium wilt of pepper (Verticillium dahliae), the efficacy of two conventional fungicides, thiophanate-methyl and carbendazim, and seaweed concentrate (SWC) from Ecklonia maxima was evaluated in greenhouse conditions. Pepper plants were inoculated with selected V. dahliae isolate in the stage of more than nine fully developed leaves on primary stem. The tested fungicides and SWC were applied three days before inoculation of pepper plants. Carbendazim was the most efficient fungicide among tested substances (69.64%). SWC proved to be more effective when applied at 1.0% concentarion (41.96%). The use of thiophanate-methyl provided good Verticillium wilt control in pepper (60.71%). SWC was less efficient than thiophanate-methyl and carbendazim, but still significantly better compared to the disease control plot.
The efficacy of mandipropamid (Revus 250 SC) in controlling Phytophthora infestans in potato was ... more The efficacy of mandipropamid (Revus 250 SC) in controlling Phytophthora infestans in potato was evaluated in field trials. The efficacies of Revus 250 SC in comparison with standard fungicides Quadris (azoxystrobin) were tested in several localities in Serbia (Kasarske Livade, Valjevska Kamenica and Opovo) in 2007 and 2008. Both of the tested fungicides exhibited high efficacy in controlling potato late blight. The differencies in the efficacy of Revus 250 SC (96.3- 99.2%) and Quadris (94.1-95.5%) were insignificant. Our experiments showed that the investigated fungicide was highly effective against P. infestans even under high disease pressure.
The efficacy of a formulated product of tea tree oil (TTO) and a standard copper based bactericid... more The efficacy of a formulated product of tea tree oil (TTO) and a standard copper based bactericide in combinations with acibenzolar-S-methyl (ASM) for control of bacterial spot of pepper and bacterial speck of tomato was evaluated under controlled conditions. Treatments with copper hydroxide+ASM at both application rates and TTO+ASM showed the best efficacy in control of bacterial spot disease in pepper plants (with respective efficacy values 83.5%, 83.7 % and 86.9%). Similar efficacy was achieved by treatment with copper hydroxide alone (82.2%). On the other hand, the efficacy of TTO, applied alone, was significantly lower at both rates (63.8% and 71.5%) in bacterial spot control in pepper. The same treatments (copper hydroxide +ASM at both application rates and TTO+ASM) were most efficient in suppressing the causal agent of bacterial speck disease in tomato (87%, 82.3% and 81.6%). The efficacy of treatment with the standard bactericide copper hydroxide, applied alone, was significantly lower compared to its combination with ASM (79.1%). Similarly to the bacterial spot experiment, TTO treatments alone showed lower, although satisfactory efficacy at both application rates (66.1% and 68.9%). The results of this study showed that combination of the bioactive compound-ASM with either the standard copper hydroxide bactericide or TTO significantly improved their efficacy in both bacterial spot and speck disease control, and thus implied that combining different biorational compounds, such as essential oils and bioactive products, with standard copper treatments and their inclusion into integrated management programs are of essential importance for the control of bacterial diseases of pepper and tomato.
Journal of Environmental Science and Health, Part B, 2018
ABSTRACT Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) ... more ABSTRACT Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) substrates (i.e., compost in different phases of composting, black peat or casing layer) in Serbia in 2014–2016 were tested in vitro against the causal agents of green mold in cultivated mushroom. Out of six most promising isolates, A06 induced 42.4% in vitro growth inhibition of Trichoderma harzianum T54, and 27.6% inhibition of T. aggressivum f. europaeum T77. The novel strain A06 was identified as Streptomyces flavovirens based on macroscopic and cultural characteristics and 16S rDNA sequence and used in mushroom growing room experiments. Actinobacteria had no negative influence on mycelial growth of the cultivated mushroom in compost in situ. Isolate S. flavovirens A06 enhanced mushroom yield significantly, up to 31.5%. The A06 isolate was more efficient in enhancing yield after inoculation with the compost mold T. aggressivum (26.1%), compared to casing mold T. harzianum (8%). Considering disease incidence, actinobacteria significantly prevented green mold in compost caused by T. aggressivum (6.8%). However, fungicide prochloraz-Mn had a more significant role in reducing symptoms of casing mold, T. harzianum, in comparison with actinobacteria (24.2 and 11.8%, respectively). No significant differences between efficacies of S. flavovirens A06 and the fungicide prochloraz-Mn against T. aggressivum were revealed. These results imply that S. flavovirens A06 can be used to increase mushroom yield and contribute to disease control against the aggressive compost green mold disease caused by Trichoderma aggressivum.
Jelena Luković1, Rada Đurović-Pejčev1, Tijana Đorđević1, Svetlana Milijašević-Marčić1, Nataša Dud... more Jelena Luković1, Rada Đurović-Pejčev1, Tijana Đorđević1, Svetlana Milijašević-Marčić1, Nataša Duduk2, Ivana Vico2 and Ivana Potočnik1* 1 Institute of Pesticides and Environmental Protection, Banatska 31b, 11080 Belgrade, Serbia 2 University of Belgrade, Faculty of Agriculture, Nemanjina 6, 11080 Belgrade, Serbia *Corresponding author: [email protected] Received: 31 December 2020 Accepted: 15 January 2021 SUMMARY
The aim of this study was to test a biofungicide based on Bacillus subtilis Ch-13 and its effecti... more The aim of this study was to test a biofungicide based on Bacillus subtilis Ch-13 and its effectiveness in the control of green mould disease of cultivated mushroom in comparison with the fungicide prochloraz. Biofungicide effectiveness in disease control and impact on yield were evaluated on Agaricus bisporus after its natural infection with Trichoderma aggressivum in a commercial mushroom growing facility. An assay for testing the microbial efficacy of the biofungicide was conducted in two different procedures involving either three or two split doses. The highest statistically significant effectiveness in green mould control was shown by the fungicide prochloraz (71.43%), followed by the biofungicide applied in tree split doses (53.57%), and finally its two doses (45.46%). The biofungicide significantly improved yield in comparison with an untreated control and the fungicide prochloraz. Three split applications of B. subtilis strain Ch-13 enhanced mushroom yield to a larger exten...
Twenty-two essential oil samples from Germany and Albania were assayed to test their inhibitory a... more Twenty-two essential oil samples from Germany and Albania were assayed to test their inhibitory and fungicidal activity against Cryphonectria parasitica (Murr.) Barr., the major causal agent of chestnut blight on chestnut trees, using the fumigant macrodilution method. Test concentrations of the oils in air phase were: 0.02, 0.04, 0.08, 0.16 and 0.32 μl ml-1 , and minimum inhibitory and fungicidal concentrations were determined. The strongest activity was shown by two samples of mint oil from Germany and Albania, and black pine at the concentration of 0.02 μl ml-1 of air for both test isolates (M1 and 4S). The tested plant essential oils also included: eucalyptus, sage, silver fir and cade. Only three samples of EOs (mint (2) and black pine) were lethal to both isolates. Sage and silver fir oils were more toxic to the M1 isolate, while cade and eucalyptus oils were more toxic to the 4S isolate. Fifteen oils: mint (2), black pine, cade, eucalyptus, silver fir, sage, pine (4), oregano, lavender, and rosemary (2), inhibited the growth of Cryphonectria parasitica, and seven oils (two samples of mint, eucaliptus, black pine, sage, silver fir and cade) showed fungicidal effects on the pathogen.
Journal of Environmental Science and Health, Part B, 2020
Twenty-two strains of Trichoderma spp. (T. harzianum species complex [THSC], Trichoderma aggressi... more Twenty-two strains of Trichoderma spp. (T. harzianum species complex [THSC], Trichoderma aggressivum f. europaeum, Trichoderma pleuroti, and Trichoderma pleuroticola) causing green mold disease on edible mushrooms (button mushroom, shiitake and oyster mushroom), collected during 2004-2018 from four countries (Serbia, North Macedonia, Croatia, and Hungary) were examined. Based on their ITS (internal transcribed spacer) sequences, strains from shiitake mushroom in Serbia were identified as members of the THSC, while in samples obtained from Serbian and North-Macedonian oyster mushroom farms THSC, T. pleuroti and T. pleuroticola were detected, which represent the first findings in the region. In fungicide susceptibility tests, all examined Trichoderma strains were found to be highly sensitive to prochloraz (ED 50 <0.4 mg mL À1) and considerably susceptible to metrafenone (ED 50 < 4 mg mL À1). The most sensitive taxon to both fungicides was THSC from oyster mushroom. The toxicity of metrafenone was satisfying and strains from oyster mushroom showed the highest sensitivity (ED 50 < 1.43 mg mL À1), while strains originating from button mushroom and shiitake displayed similar susceptibilities (ED 50 < 3.64 mg mL À1). After additional in vivo trials, metrafenone might also be recommended for the control of green mold disease in mushroom farms.
Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. c... more Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. campestris pv. phaseoli, the causal agent of common blight of beans, following leaf-spray inoculation with bacterial suspension (108 cfu/ml). The plants were evaluated based on the number of leaf lesions, and the disease severity index (DSI) was calculated. The evaluated genotypes showed various levels of susceptibility to X. campestris pv. phaseoli strain VS-1. The results of both experiments showed that the cultivar Oreol was the most resistant. The genotypes: KB 142, HR-45, Tisa and Panonski tetovac also showed low susceptibility with DSI values in the first trial ranging from 2.27 to 3.60. The same genotypes, with the exception of Panonski tetovac, were also categorized as low-susceptible to the bacterium in the second experiment, having the DSI values between 2.27 and 3.60. Most genotypes (Slavonski žutozeleni, Zlatko, Biser, Sremac, Naya Nayahit) were categorized as susceptible in t...
Cladobotryum dendroides is the most frequently found soil-borne mushroom pathogen in Serbia [1]. ... more Cladobotryum dendroides is the most frequently found soil-borne mushroom pathogen in Serbia [1]. Although many investigations have been carried out to find an adequate disinfectant of mushroom casing, so far, none has been found to be completely effective thus non-toxic to humans. The aim of this study was to explore the potential of Ecocute, based on colloidal silver [2-3] and Peral-S (active oxygen) [4-5], as environmentally friendly casing disinfectants. Efficacies of the disinfectants and incidence of cobweb disease were evaluated in bags of compost cased with a black peat/lime casing soil, previously disinfected with Ecocute at 30 mg L -1 per m 2 and Peral-S at 1.7 ml L -1 per m 2 . Plots were inoculated with suspension set on 1000 conidia per m 2 of C. dendroides. Both disinfectants were applied alone and in combination with prochloraz-manganese. Biological efficiency of colloidal silver applied alone was higher than in treatments with active oxygen in all trials. The colloida...
... in vitro BrankicaTanovic, Svetlana Milijasevic, Biljana Todorovic, Ivana Potocnik i Emil Reka... more ... in vitro BrankicaTanovic, Svetlana Milijasevic, Biljana Todorovic, Ivana Potocnik i Emil Rekanovic Institut "Sròija", Centar za pesticide i zastitu zivotne sredine, Beograd-Zemun REZIME Prouceno je delovanje gasovite faze etarskih ulja standardnog kvaliteta 18 vrsta bil-jaka ...
Several methods used for the detection of Clavibacter michiganensis subsp. michiganensis (Cmm) in... more Several methods used for the detection of Clavibacter michiganensis subsp. michiganensis (Cmm) in artificially infested tomato seed lots were evaluated using two seed extraction methods (grinding and soaking). The detection threshold was evaluated by adding different numbers of artificially infested seeds (one, five and ten) to noninfected seed samples of two different sizes: 2000 and 5000 seeds. Four detection methods were simultaneously compared for their sensitivity in Cmm detection in seeds: isolation on selective media, direct PCR from seed material, Bio-PCR which first cultured bacteria on NBY agar prior to PCR, and Enrichment PCR. In samples of 2000 seeds containing one, five and ten infested seeds, the pathogen was detected in at least four out of five replicates by three detection methods (selective plating, direct PCR and Bio-PCR), using both the grinding extraction method (with an addition of centrifugation step) and soaking. DNA extraction from seed material was needed before the Enrichment PCR and direct PCR amplifications were performed. In samples of 5000 seeds one infested seed could not be detected by direct PCR or Enrichment PCR in any of the five replicates, regardless of the seed extraction method used. In samples containing five infested seeds per 5000 seeds, Cmm was detected by all four detection methods. A comparison of the efficiency of detection of the pathogen by using extraction methods that included grinding and soaking showed no differences between them.
Monitoring of button mushroom bacterial diseases was conducted to estimate the presence and ident... more Monitoring of button mushroom bacterial diseases was conducted to estimate the presence and identity of mycopathogenic bacteria and to determine the predominant bacterial pathogen in Serbia. Samples were collected from mushroom farms during 2006- 2010 and also from fresh markets during 2014-2015. The collected samples showed either symptoms of brown blotch or different degrees of brown discoloration on caps and stalks of Agaricus bisporus resembling bacterial infection. The presence of bacterial droplets on gills was not recorded. The isolated bacteria were Gram-negative and fluorescent on King?s medium B. In pathogenicity tests, most bacterial isolates induced superficial or sunken brown lesions with differences in the level of discoloration on A. bisporus tissue blocks after artificial inoculation. Based on LOPAT characteristics, the isolates were divided into two groups, showing characteristics of either the LOPAT group Va or group III. Based on these features and other different...
World Journal of Microbiology and Biotechnology, 2019
Lignocellulosic plant biomass is the world's most abundant carbon source and has consequently att... more Lignocellulosic plant biomass is the world's most abundant carbon source and has consequently attracted attention as a renewable resource for production of biofuels and commodity chemicals that could replace fossil resources. Due to its recalcitrant nature, it must be pretreated by chemical, physical or biological means prior to hydrolysis, introducing additional costs. In this paper, we tested the hypothesis that fungi which thrive on lignocellulosic material (straw, bark or soil) would be efficient in degrading untreated lignocellulose. Wheat straw was used as a model. We developed a fast and simple screening method for cellulase producers and tested one hundred Trichoderma strains isolated from wheat straw. The most potent strain-UB483FTG2/ TUCIM 4455, was isolated from substrate used for mushroom cultivation and was identified as T. guizhouense. After optimization of growth medium, high cellulase activity was already achieved after 72 h of fermentation on raw wheat straw, while the model cellulase overproducing strain T. reesei QM 9414 took 170 h and reached only 45% of the cellulase activity secreted by T. guizhouense. Maximum production levels were 1.1 U/mL (measured with CMC as cellulase substrate) and 0.7 U/mL (β-glucosidase assay). The T. guizhouense cellulase cocktail hydrolyzed raw wheat straw within 35 h. Our study shows that screening for fungi that successfully compete for special substrates in nature will lead to the isolation of strains with qualitatively and quantitatively superior enzymes needed for their digestion which could be used for industrial purposes.
In vitro antagonistic potential of eleven isolates of Bacillus spp. against two phytopathogenic b... more In vitro antagonistic potential of eleven isolates of Bacillus spp. against two phytopathogenic bacteria and one fungus was tested in order to identify potential biocontrol agents in vegetable crops. The Bacillus spp. isolates demonstrated different levels of antagonistic effect against the tested pathogenic microorganisms. Data in the study proved Xanthomonas vesicatoria to be more sensitive to Bacillus spp. strains than Clavibacter michiganensis subsp. michiganensis. Ten B. subtilis strains induced growth inhibition of X. vesicatoria, while a strain of B. pumilus did not affect the growth of that bacterium. The largest inhibition zones against X. vesicatoria were induced by strains B-319, B-325 and B-358. The pathogenic strain C. michiganensis subsp. michiganensis was most inhibited by two B. subtilis strains (B-338 and B-348) with mean inhibition zone diameters of up to 20 mm. B. subtilis strain B-319 which was the best in inhibiting X. vesicatoria, showed the lowest inhibitory e...
Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. c... more Plants of 17 bean genotypes were evaluated under greenhouse conditions for their reaction to X. campestris pv. phaseoli, the causal agent of common blight of beans, following leaf-spray inoculation with bacterial suspension (108 cfu/ml). The plants were evaluated based on the number of leaf lesions, and the disease severity index (DSI) was calculated. The evaluated genotypes showed various levels of susceptibility to X. campestris pv. phaseoli strain VS-1. The results of both experiments showed that the cultivar Oreol was the most resistant. The genotypes: KB 142, HR-45, Tisa and Panonski tetovac also showed low susceptibility with DSI values in the first trial ranging from 2.27 to 3.60. The same genotypes, with the exception of Panonski tetovac, were also categorized as low-susceptible to the bacterium in the second experiment, having the DSI values between 2.27 and 3.60. Most genotypes (Slavonski zutozeleni, Zlatko, Biser, Sremac, Naya Nayahit) were categorized as susceptible in t...
In order to control the causal agent of Verticillium wilt of pepper (Verticillium dahliae), the e... more In order to control the causal agent of Verticillium wilt of pepper (Verticillium dahliae), the efficacy of two conventional fungicides, thiophanate-methyl and carbendazim, and seaweed concentrate (SWC) from Ecklonia maxima was evaluated in greenhouse conditions. Pepper plants were inoculated with selected V. dahliae isolate in the stage of more than nine fully developed leaves on primary stem. The tested fungicides and SWC were applied three days before inoculation of pepper plants. Carbendazim was the most efficient fungicide among tested substances (69.64%). SWC proved to be more effective when applied at 1.0% concentarion (41.96%). The use of thiophanate-methyl provided good Verticillium wilt control in pepper (60.71%). SWC was less efficient than thiophanate-methyl and carbendazim, but still significantly better compared to the disease control plot.
The efficacy of mandipropamid (Revus 250 SC) in controlling Phytophthora infestans in potato was ... more The efficacy of mandipropamid (Revus 250 SC) in controlling Phytophthora infestans in potato was evaluated in field trials. The efficacies of Revus 250 SC in comparison with standard fungicides Quadris (azoxystrobin) were tested in several localities in Serbia (Kasarske Livade, Valjevska Kamenica and Opovo) in 2007 and 2008. Both of the tested fungicides exhibited high efficacy in controlling potato late blight. The differencies in the efficacy of Revus 250 SC (96.3- 99.2%) and Quadris (94.1-95.5%) were insignificant. Our experiments showed that the investigated fungicide was highly effective against P. infestans even under high disease pressure.
The efficacy of a formulated product of tea tree oil (TTO) and a standard copper based bactericid... more The efficacy of a formulated product of tea tree oil (TTO) and a standard copper based bactericide in combinations with acibenzolar-S-methyl (ASM) for control of bacterial spot of pepper and bacterial speck of tomato was evaluated under controlled conditions. Treatments with copper hydroxide+ASM at both application rates and TTO+ASM showed the best efficacy in control of bacterial spot disease in pepper plants (with respective efficacy values 83.5%, 83.7 % and 86.9%). Similar efficacy was achieved by treatment with copper hydroxide alone (82.2%). On the other hand, the efficacy of TTO, applied alone, was significantly lower at both rates (63.8% and 71.5%) in bacterial spot control in pepper. The same treatments (copper hydroxide +ASM at both application rates and TTO+ASM) were most efficient in suppressing the causal agent of bacterial speck disease in tomato (87%, 82.3% and 81.6%). The efficacy of treatment with the standard bactericide copper hydroxide, applied alone, was significantly lower compared to its combination with ASM (79.1%). Similarly to the bacterial spot experiment, TTO treatments alone showed lower, although satisfactory efficacy at both application rates (66.1% and 68.9%). The results of this study showed that combination of the bioactive compound-ASM with either the standard copper hydroxide bactericide or TTO significantly improved their efficacy in both bacterial spot and speck disease control, and thus implied that combining different biorational compounds, such as essential oils and bioactive products, with standard copper treatments and their inclusion into integrated management programs are of essential importance for the control of bacterial diseases of pepper and tomato.
Journal of Environmental Science and Health, Part B, 2018
ABSTRACT Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) ... more ABSTRACT Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) substrates (i.e., compost in different phases of composting, black peat or casing layer) in Serbia in 2014–2016 were tested in vitro against the causal agents of green mold in cultivated mushroom. Out of six most promising isolates, A06 induced 42.4% in vitro growth inhibition of Trichoderma harzianum T54, and 27.6% inhibition of T. aggressivum f. europaeum T77. The novel strain A06 was identified as Streptomyces flavovirens based on macroscopic and cultural characteristics and 16S rDNA sequence and used in mushroom growing room experiments. Actinobacteria had no negative influence on mycelial growth of the cultivated mushroom in compost in situ. Isolate S. flavovirens A06 enhanced mushroom yield significantly, up to 31.5%. The A06 isolate was more efficient in enhancing yield after inoculation with the compost mold T. aggressivum (26.1%), compared to casing mold T. harzianum (8%). Considering disease incidence, actinobacteria significantly prevented green mold in compost caused by T. aggressivum (6.8%). However, fungicide prochloraz-Mn had a more significant role in reducing symptoms of casing mold, T. harzianum, in comparison with actinobacteria (24.2 and 11.8%, respectively). No significant differences between efficacies of S. flavovirens A06 and the fungicide prochloraz-Mn against T. aggressivum were revealed. These results imply that S. flavovirens A06 can be used to increase mushroom yield and contribute to disease control against the aggressive compost green mold disease caused by Trichoderma aggressivum.
Jelena Luković1, Rada Đurović-Pejčev1, Tijana Đorđević1, Svetlana Milijašević-Marčić1, Nataša Dud... more Jelena Luković1, Rada Đurović-Pejčev1, Tijana Đorđević1, Svetlana Milijašević-Marčić1, Nataša Duduk2, Ivana Vico2 and Ivana Potočnik1* 1 Institute of Pesticides and Environmental Protection, Banatska 31b, 11080 Belgrade, Serbia 2 University of Belgrade, Faculty of Agriculture, Nemanjina 6, 11080 Belgrade, Serbia *Corresponding author: [email protected] Received: 31 December 2020 Accepted: 15 January 2021 SUMMARY
The aim of this study was to test a biofungicide based on Bacillus subtilis Ch-13 and its effecti... more The aim of this study was to test a biofungicide based on Bacillus subtilis Ch-13 and its effectiveness in the control of green mould disease of cultivated mushroom in comparison with the fungicide prochloraz. Biofungicide effectiveness in disease control and impact on yield were evaluated on Agaricus bisporus after its natural infection with Trichoderma aggressivum in a commercial mushroom growing facility. An assay for testing the microbial efficacy of the biofungicide was conducted in two different procedures involving either three or two split doses. The highest statistically significant effectiveness in green mould control was shown by the fungicide prochloraz (71.43%), followed by the biofungicide applied in tree split doses (53.57%), and finally its two doses (45.46%). The biofungicide significantly improved yield in comparison with an untreated control and the fungicide prochloraz. Three split applications of B. subtilis strain Ch-13 enhanced mushroom yield to a larger exten...
Twenty-two essential oil samples from Germany and Albania were assayed to test their inhibitory a... more Twenty-two essential oil samples from Germany and Albania were assayed to test their inhibitory and fungicidal activity against Cryphonectria parasitica (Murr.) Barr., the major causal agent of chestnut blight on chestnut trees, using the fumigant macrodilution method. Test concentrations of the oils in air phase were: 0.02, 0.04, 0.08, 0.16 and 0.32 μl ml-1 , and minimum inhibitory and fungicidal concentrations were determined. The strongest activity was shown by two samples of mint oil from Germany and Albania, and black pine at the concentration of 0.02 μl ml-1 of air for both test isolates (M1 and 4S). The tested plant essential oils also included: eucalyptus, sage, silver fir and cade. Only three samples of EOs (mint (2) and black pine) were lethal to both isolates. Sage and silver fir oils were more toxic to the M1 isolate, while cade and eucalyptus oils were more toxic to the 4S isolate. Fifteen oils: mint (2), black pine, cade, eucalyptus, silver fir, sage, pine (4), oregano, lavender, and rosemary (2), inhibited the growth of Cryphonectria parasitica, and seven oils (two samples of mint, eucaliptus, black pine, sage, silver fir and cade) showed fungicidal effects on the pathogen.
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