Raheleh Ghale Ghafi; Hossein HajiAbaee; Fathieh Nabhani; Salvia Mohammadpour; Zahra Ardanji Kalate Siyahdasht
Abstract
Objective: This study was conducted with the aim of investigating the influence of mycorrhizal fungi (Rhizophagus irigularis) and rhizobacteria (Pseudomonas fluorescens) inoculation on maize under different fertilization conditions.Methods: This study was carried out in two separate experiments under ...
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Objective: This study was conducted with the aim of investigating the influence of mycorrhizal fungi (Rhizophagus irigularis) and rhizobacteria (Pseudomonas fluorescens) inoculation on maize under different fertilization conditions.Methods: This study was carried out in two separate experiments under greenhouse settings in 2018. The first experiment aimed to compare the conventional soil inoculation method with microbial seed coating, and the second experiment strived to assess the growth of maize inoculated with mycorrhizal fungi and plant growth-promoting rhizobacteria via microbial seed coating at three treatment levels of Hoagland nutrient solution (Control, 80 and 100 volumetric percentage of Hoagland solution). In both experiments, one gram of maize roots and adhering soil were sampled 70 days after microbial seed coating and the available DNA was extracted from the maize rhizosphere.Results: In the first experiment, no significant difference was observed between conventional soil inoculation and microbial seed coating concerning the dry weight of stems and roots, longitudinal colonization percentage of the roots, arbuscule abundance, vesicles abundance, and elemental concentration. In the second experiment and under full fertilization condition, mycorrhizal inoculation resulted in a significant increase in concentrations of nitrogen, phosphorus, potassium, and zinc (18.1, 3.5, 56 and 46.0 mg/kg, respectively) compared to the control treatment (12.6, 3.1, 39.6, and 24.4 mg/kg, respectively), and the bacterial inoculation exhibited a significant increase for magnesium, zinc, and manganese (2.0, 42.6, and 145 mg/kg, respectively) compared to the control treatment (1.0, 24.4, and 60 mg/kg, respectively).Conclusion: Microbial seed coating could be regarded as a novel approach of large-scale inoculation of microorganisms in maize production.
Mehdi Rashtbari; Ali Akbar Safari Sinegani
Abstract
The present study evaluates the effect of various application methods of mostly applied antibiotics in agriculture (gentamicin, oxytetracycline, penicillin) at different concentrations on root and shoot growth indices and number of rhizobial nodules of chickpea plant and the count of total bacteria, ...
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The present study evaluates the effect of various application methods of mostly applied antibiotics in agriculture (gentamicin, oxytetracycline, penicillin) at different concentrations on root and shoot growth indices and number of rhizobial nodules of chickpea plant and the count of total bacteria, fungi, and coliforms in the soil around the plant root after a growth period of 60 days in greenhouse as a split-plot design. Application of antibiotics, even gentamicin, raises plant shoot dry weight, compared to the control, with the lowest weight of 0.98 g/pot observed in the control (without antibiotic). Root dry weight in penicillin-applied treatments, especially at higher concentrations has been the highest (1.1 g/pot), and the lowest in gentamicin-applied treatments, especially when applied as seed coating (0.48 g/pot). In total, antibiotic application decreases the root to shoot ratio compared to the control. Application of all antibiotics increase soil bacterial count in the pots after 60 days in comparison with the control. Also, increasing the concentration of gentamicin and penicillin, decreases plant root nodule number by 78.8% and 59.7%, respectively. Overall, the effect of antibiotics on soil microbial count and plant growth depends on antibiotic type and application method.
Khadijeh Shahsavarpour Lendeh; Hemmatollah Pirdashti; Esmaeil Bakhshandeh
Abstract
In order to investigate the effect of a native plant growth promoting bacteria (Enterobacter sp.) on some vegetative characteristics and paddy yield of rice(cv. ‘Tarom Hashemi’), a field experiment was carried out in Babol (Aghamalek village) at 2016. This experiment was arranged in split ...
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In order to investigate the effect of a native plant growth promoting bacteria (Enterobacter sp.) on some vegetative characteristics and paddy yield of rice(cv. ‘Tarom Hashemi’), a field experiment was carried out in Babol (Aghamalek village) at 2016. This experiment was arranged in split plots based on a randomized complete block design with three replications. Six levels of potassium sulfate fertilizer (PSF: 0, 25, 50, 75, 100 and 125 kg ha-1) were used as the main plots and four levels of inoculations (non-inoculation as control, seed inoculation in the seedbed condition, seedling root inoculation before transplanting time and combined both previously methods) served as the sub-plots. The results indicated that various methods of inoculation increased plant height (1.25-2.54%), tillers number per hill (TNH; 11.7-16.5%), total leaves number per hill (TLN; 12.5-14.2%), leaf area index (LAI; 7.16-17.9%) and paddy yield (PY; 14.6-19.8%) of rice and the occurring of anthesis stage were about one day sooner as compared to the control condition. In this experiment, the studied traits significantly influenced by PSF and various methods of inoculation, but the interaction effect between them were not significant. Among inoculation methods, the combined method was better than others. In addition, the values of all studied traits such as PH, TNH, TLN, LAI and PY (18.2% more than the control) increased as PSF increased from zero to 125 kg ha-1. Consequently, the application of Enterobacter sp. and PSF through improved the vegetative characteristics, particularly in LAI, TNH and TLN, resulted to increase in the radiation interception capacity, photosynthetic efficiency and improved PY of rice.