Suitable conditions bring about high population of pests or diseases in green-houses and therefor... more Suitable conditions bring about high population of pests or diseases in green-houses and therefore, frequent applications of pesticides occur in this production system which causes public anxiety about pesticide residue in green-house grown crops such as tomato. The present report is the result of an investigation performed on pesticide residue level measurements in green-house grown tomato in Hamadan province. In this study, 43 tomato samples were taken from the green-houses across the province and the residue levels of nine pesticides in each sample were measured. The results indicated that 95.4% of the samples were completely free of all measured insecticides. In 4.6% of the samples the residue of Chlorpyrifos was detected of which the residue level of only one sample (2.3%) was higher than the Maximum residue limit (MRL) for this pesticide in tomato (MRL = 0.1 ppm).
In this study the effect of Wormwood extract on the growth of Fusarium solani, was evaluated in v... more In this study the effect of Wormwood extract on the growth of Fusarium solani, was evaluated in vitro . The assessment was done by conducting an experiment as a completely randomized design with six treatments and four replications. The treatments were four concentrations of Wormwood extract (400, 600, 800 and 1000 mg ml -1 ) and two controls (distilled water and fungicide solution). Each treatment was applied to the fungus by diffusing through a paper disc loaded with each treatment and placed in the center of a plate of PDA medium inoculated with spore suspension of the fungus. Measuring the average diameter of F. solani growth inhibition zone around the paper discs loaded with each of the treatments indicated that compared to the negative control, all concentrations of Wormwood extract could significantly inhibit mycelial growth of the fungus. The concentrations 1000mg ml -1 and 800mg ml -1 of the extract inhibited growth of F. solani by %23.08 and %19.13, respectively. Moreover,...
In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLR... more In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLRV) were evaluated. The assessment was performed in a field trial exposure in which the test plants were planted in a randomized complete block design. The experimental design consisted of 12 treatments with three replications. The treatments were six known potato cultivars and six potato genotypes. Each plot of the design included a planting row of five plants from each cultivar/genotype. When the test plants reached about 15 cm, they were inoculated with PLRV by 10 PLRV-carrying aphids on each Plant. Ten days later, the aphids were killed. One month after inoculation, the plants were examined for PLRV infection by observing symptom development and using enzyme-linked immunosorbent assay (ELISA) test. The results indicated that there were significant differences between the PLRV-infection rates of the potato cultivars/genotypes tested. The genotype 803970/13 (showing no infection) was ev...
Journal of Natural Product and Plant Resources, 2015
In this study the effect of garden time (Thymus vulgaris) extract on the growth of Aspergillus fl... more In this study the effect of garden time (Thymus vulgaris) extract on the growth of Aspergillus flavus, the major producer of aflatoxin, was evaluated in vitro. The assessment was done by conducting an experiment as a completely randomized design with six treatments and four replications. The treatments were four concentrations of garden time extract (150, 300, 450 and 600 mg/ml) and two controls (distilled water and fungicide solution). Each treatment was applied to the fungus by diffusing through a paper disc loaded with each treatment and placed in the center of a plate of PDA medium inoculated with spore suspension of the fungus. Measuring the average radius of A. flavus growth inhibition zone around the paper discs loaded with each of the treatments indicated that compared to the negative control, three concentrations of garden time (300, 450 and 600 mg/ml) could significantly inhibit mycelial growth of the fungus. After the treatment fungicide, the highest growth inhibition zon...
Background & Aim: The aim of this study was to assess the antifungal effect of the watercress ext... more Background & Aim: The aim of this study was to assess the antifungal effect of the watercress extract on the growth of Fusarium solani, the causal agent of potato dry rot. Experimental: This research was done in a completely randomized design with three concentrations and four replicates on potato dextrose agar (PDA) culture medium. Results: Results of this study indicated that all concentrations of alcoholic extract of watercress can significantly inhibit mycelia growth of Fusarium solani on PDA medium. Among different concentrations of watercress extract, the highest inhibition zone of the fungus (26.1 mm in diameter) was obtained at dose of 600 mg/ml. The rate of growth inhibition was concentration dependent. However, no significant difference in the rate of growth inhibition of the fungus by watercress extract was seen between the 500 mg/ml and 400 mg/ml or between 400 mg/ml and 300 mg/ml of the plant extract. Recommended applications/industries: The overall results of this expe...
Two field experiments were conducted and executed during 2015 and 2016 to evaluate the effectiven... more Two field experiments were conducted and executed during 2015 and 2016 to evaluate the effectiveness of six newly developed fungal bioformulations in controlling garlic white rot disease caused by Sclerotium cepivorum. The bioformulations were developed using three antagonistic fungi including Trichoderma harzianum, T. asperellum and Talaromyces flavus and rice bran as an organic carrier. They were selected based on their performance in the greenhouse conditions in a previous study, where they effectively controlled and reduced the garlic white rot disease. Field trials were conducted in a randomized complete blocks design with eight treatments (six bioformulations, an untreated control and a Carbendazim fungicide) each with four replicates. The garlic seeds (bulbs) were coated with each bioformulation and were sown in the field soil preinoculated with S. cepivorum. The incidence and the index of white rot disease severity were then determined in different treatments 90 days after s...
International Journal of Biological Advances, 2015
In this study the effect of garden time (Thymus vulgaris) essential oil on the growth of Aspergil... more In this study the effect of garden time (Thymus vulgaris) essential oil on the growth of Aspergillus flavus, the major producer of aflatoxin, was evaluated in vitro. The assessment was done by conducting an experimental completely randomized design comprising of six treatments and four replications. The treatments were four concentrations of garden time essential oil (0.2, 0.6, 1 and 1.4 mg/ml) and two controls (Dimethyl sulfoxide and fungicide solutions). Each treatment was applied to the fungus by placing a paper disc, impregnated with each treatment, in the center of a plate of PDA medium inoculated with spore suspension of the fungus. Measuring the average radius of A. flavus growth inhibition zone around the impregnated paper discs indicated that compared to the negative control, all concentrations of garden time essential oil significantly inhibited the mycelial growth of the fungus. The highest radial growth inhibition zone (20.5 mm, 18 mm and 10.7 mm) were those of 1.4 mg/ml...
Background & Aim: The aim of this study was to assess the antifungal effect of the watercress ext... more Background & Aim: The aim of this study was to assess the antifungal effect of the watercress extract on the growth of Fusarium solani, the causal agent of potato dry rot. Experimental: This research was done in a completely randomized design with three concentrations and four replicates on potato dextrose agar (PDA) culture medium. Results: Results of this study indicated that all concentrations of alcoholic extract of watercress can significantly inhibit mycelia growth of Fusarium solani on PDA medium. Among different concentrations of watercress extract, the highest inhibition zone of the fungus (26.1 mm in diameter) was obtained at dose of 600 mg/ml. The rate of growth inhibition was concentration dependent. However, no significant difference in the rate of growth inhibition of the fungus by watercress extract was seen between the 500 mg/ml and 400 mg/ml or between 400 mg/ml and 300 mg/ml of the plant extract. Recommended applications/industries: The overall results of this expe...
In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLR... more In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLRV) were evaluated. The assessment was performed in a field trial exposure in which the test plants were planted in a randomized complete block design. The experimental design consisted of 12 treatments with three replications. The treatments were six known potato cultivars and six potato genotypes. Each plot of the design included a planting row of five plants from each cultivar/genotype. When the test plants reached about 15 cm, they were inoculated with PLRV by 10 PLRV-carrying aphids on each Plant. Ten days later, the aphids were killed. One month after inoculation, the plants were examined for PLRV infection by observing symptom development and using enzyme-linked immunosorbent assay (ELISA) test. The results indicated that there were significant differences between the PLRV-infection rates of the potato cultivars/genotypes tested. The genotype 803970/13 (showing no infection) was ev...
Suitable conditions bring about high population of pests or diseases in green-houses and therefor... more Suitable conditions bring about high population of pests or diseases in green-houses and therefore, frequent applications of pesticides occur in this production system which causes public anxiety about pesticide residue in green-house grown crops such as tomato. The present report is the result of an investigation performed on pesticide residue level measurements in green-house grown tomato in Hamadan province. In this study, 43 tomato samples were taken from the green-houses across the province and the residue levels of nine pesticides in each sample were measured. The results indicated that 95.4% of the samples were completely free of all measured insecticides. In 4.6% of the samples the residue of Chlorpyrifos was detected of which the residue level of only one sample (2.3%) was higher than the Maximum residue limit (MRL) for this pesticide in tomato (MRL = 0.1 ppm).
In this study the effect of Wormwood extract on the growth of Fusarium solani, was evaluated in v... more In this study the effect of Wormwood extract on the growth of Fusarium solani, was evaluated in vitro . The assessment was done by conducting an experiment as a completely randomized design with six treatments and four replications. The treatments were four concentrations of Wormwood extract (400, 600, 800 and 1000 mg ml -1 ) and two controls (distilled water and fungicide solution). Each treatment was applied to the fungus by diffusing through a paper disc loaded with each treatment and placed in the center of a plate of PDA medium inoculated with spore suspension of the fungus. Measuring the average diameter of F. solani growth inhibition zone around the paper discs loaded with each of the treatments indicated that compared to the negative control, all concentrations of Wormwood extract could significantly inhibit mycelial growth of the fungus. The concentrations 1000mg ml -1 and 800mg ml -1 of the extract inhibited growth of F. solani by %23.08 and %19.13, respectively. Moreover,...
In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLR... more In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLRV) were evaluated. The assessment was performed in a field trial exposure in which the test plants were planted in a randomized complete block design. The experimental design consisted of 12 treatments with three replications. The treatments were six known potato cultivars and six potato genotypes. Each plot of the design included a planting row of five plants from each cultivar/genotype. When the test plants reached about 15 cm, they were inoculated with PLRV by 10 PLRV-carrying aphids on each Plant. Ten days later, the aphids were killed. One month after inoculation, the plants were examined for PLRV infection by observing symptom development and using enzyme-linked immunosorbent assay (ELISA) test. The results indicated that there were significant differences between the PLRV-infection rates of the potato cultivars/genotypes tested. The genotype 803970/13 (showing no infection) was ev...
Journal of Natural Product and Plant Resources, 2015
In this study the effect of garden time (Thymus vulgaris) extract on the growth of Aspergillus fl... more In this study the effect of garden time (Thymus vulgaris) extract on the growth of Aspergillus flavus, the major producer of aflatoxin, was evaluated in vitro. The assessment was done by conducting an experiment as a completely randomized design with six treatments and four replications. The treatments were four concentrations of garden time extract (150, 300, 450 and 600 mg/ml) and two controls (distilled water and fungicide solution). Each treatment was applied to the fungus by diffusing through a paper disc loaded with each treatment and placed in the center of a plate of PDA medium inoculated with spore suspension of the fungus. Measuring the average radius of A. flavus growth inhibition zone around the paper discs loaded with each of the treatments indicated that compared to the negative control, three concentrations of garden time (300, 450 and 600 mg/ml) could significantly inhibit mycelial growth of the fungus. After the treatment fungicide, the highest growth inhibition zon...
Background & Aim: The aim of this study was to assess the antifungal effect of the watercress ext... more Background & Aim: The aim of this study was to assess the antifungal effect of the watercress extract on the growth of Fusarium solani, the causal agent of potato dry rot. Experimental: This research was done in a completely randomized design with three concentrations and four replicates on potato dextrose agar (PDA) culture medium. Results: Results of this study indicated that all concentrations of alcoholic extract of watercress can significantly inhibit mycelia growth of Fusarium solani on PDA medium. Among different concentrations of watercress extract, the highest inhibition zone of the fungus (26.1 mm in diameter) was obtained at dose of 600 mg/ml. The rate of growth inhibition was concentration dependent. However, no significant difference in the rate of growth inhibition of the fungus by watercress extract was seen between the 500 mg/ml and 400 mg/ml or between 400 mg/ml and 300 mg/ml of the plant extract. Recommended applications/industries: The overall results of this expe...
Two field experiments were conducted and executed during 2015 and 2016 to evaluate the effectiven... more Two field experiments were conducted and executed during 2015 and 2016 to evaluate the effectiveness of six newly developed fungal bioformulations in controlling garlic white rot disease caused by Sclerotium cepivorum. The bioformulations were developed using three antagonistic fungi including Trichoderma harzianum, T. asperellum and Talaromyces flavus and rice bran as an organic carrier. They were selected based on their performance in the greenhouse conditions in a previous study, where they effectively controlled and reduced the garlic white rot disease. Field trials were conducted in a randomized complete blocks design with eight treatments (six bioformulations, an untreated control and a Carbendazim fungicide) each with four replicates. The garlic seeds (bulbs) were coated with each bioformulation and were sown in the field soil preinoculated with S. cepivorum. The incidence and the index of white rot disease severity were then determined in different treatments 90 days after s...
International Journal of Biological Advances, 2015
In this study the effect of garden time (Thymus vulgaris) essential oil on the growth of Aspergil... more In this study the effect of garden time (Thymus vulgaris) essential oil on the growth of Aspergillus flavus, the major producer of aflatoxin, was evaluated in vitro. The assessment was done by conducting an experimental completely randomized design comprising of six treatments and four replications. The treatments were four concentrations of garden time essential oil (0.2, 0.6, 1 and 1.4 mg/ml) and two controls (Dimethyl sulfoxide and fungicide solutions). Each treatment was applied to the fungus by placing a paper disc, impregnated with each treatment, in the center of a plate of PDA medium inoculated with spore suspension of the fungus. Measuring the average radius of A. flavus growth inhibition zone around the impregnated paper discs indicated that compared to the negative control, all concentrations of garden time essential oil significantly inhibited the mycelial growth of the fungus. The highest radial growth inhibition zone (20.5 mm, 18 mm and 10.7 mm) were those of 1.4 mg/ml...
Background & Aim: The aim of this study was to assess the antifungal effect of the watercress ext... more Background & Aim: The aim of this study was to assess the antifungal effect of the watercress extract on the growth of Fusarium solani, the causal agent of potato dry rot. Experimental: This research was done in a completely randomized design with three concentrations and four replicates on potato dextrose agar (PDA) culture medium. Results: Results of this study indicated that all concentrations of alcoholic extract of watercress can significantly inhibit mycelia growth of Fusarium solani on PDA medium. Among different concentrations of watercress extract, the highest inhibition zone of the fungus (26.1 mm in diameter) was obtained at dose of 600 mg/ml. The rate of growth inhibition was concentration dependent. However, no significant difference in the rate of growth inhibition of the fungus by watercress extract was seen between the 500 mg/ml and 400 mg/ml or between 400 mg/ml and 300 mg/ml of the plant extract. Recommended applications/industries: The overall results of this expe...
In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLR... more In this study, the reactions of some potato cultivars and genotypes to Potato leafroll virus (PLRV) were evaluated. The assessment was performed in a field trial exposure in which the test plants were planted in a randomized complete block design. The experimental design consisted of 12 treatments with three replications. The treatments were six known potato cultivars and six potato genotypes. Each plot of the design included a planting row of five plants from each cultivar/genotype. When the test plants reached about 15 cm, they were inoculated with PLRV by 10 PLRV-carrying aphids on each Plant. Ten days later, the aphids were killed. One month after inoculation, the plants were examined for PLRV infection by observing symptom development and using enzyme-linked immunosorbent assay (ELISA) test. The results indicated that there were significant differences between the PLRV-infection rates of the potato cultivars/genotypes tested. The genotype 803970/13 (showing no infection) was ev...
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