Raheleh Ghale Ghafi; Hossein HajiAbaee; Fathieh Nabhani; Salvia Mohammadpour; Zahra Ardanji Kalate Siyahdasht
Abstract
This study was carried out to investigate the effect of mycorrhizal fungi (Rhizophagus irigularis) and rhizobacteria (Pseudomonas fluorescens) on maize under different fertilization conditions as greenhouse research in the Jalin region of Gorgan in 2018 during two separate experiments. The aim of the ...
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This study was carried out to investigate the effect of mycorrhizal fungi (Rhizophagus irigularis) and rhizobacteria (Pseudomonas fluorescens) on maize under different fertilization conditions as greenhouse research in the Jalin region of Gorgan in 2018 during two separate experiments. The aim of the first experiment was to compare the conventional soil incubation with seed-coating incubation, and the second experiment was to assess the growth of maize incubated with mycorrhizal fungi and plant growth-promoting rhizobacteria through seed-coating at three treatment levels of Hoagland nutrient solution (Control, 80 and 100 volumetric percentage of Hoagland solution). In both experiments, at 70 days after seed-coating, one gram of maize roots and soil attached to it were sampled and DNA was extracted from the maize rhizosphere. In the first experiment, there was no significant difference between the conventional soil incubation and seed-coating incubation according to the dry weight of stems and roots, roots’ longitudinal colonization percentage, arboscol abundance, vesicles abundance, and elements concentration. In the second experiment and under full fertilizing conditions, mycorrhizal incubation showed 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 (12.6, 3.1, 39.6, and 24.4 mg/kg, respectively), and the bacterial incubation showed a significant increase for magnesium, zinc, and manganese (2.0, 42.6, and 145 mg/kg, respectively) compared to the control (1.0, 24.4, and 60 mg/kg, respectively).
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.