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Yadegari M.,Islamic Azad University | Rahmani H.A.,Soil and Water Research Institute
African Journal of Agricultural Research | Year: 2010

Growing evidence indicates that soil beneficial bacteria can positively affect symbiotic performance of rhizobia. The effect of co-inoculation with plant growth-promoting rhizobacteria (PGPR) and Rhizobium, on yield and yield components of common bean (Phaseolus vulgaris L.) cultivars was investigated in two consecutive years under field condition. PGPR strains Pseudomonas fluorescens P-93 and Azospirillum lipoferum S-21 as well as two highly effective Rhizobium strains were used in this study. Common bean seeds of three cultivars were inoculated with Rhizobium singly or in a combination with PGPR to evaluate their effect on growth characters. A significant variation of plant growth in response to inoculation with Rhizobium strains was observed. Treatment with PGPR significantly increased pod per plant, number of seeds per pod, weight of 100 seed, weight of seeds per plant, weight of pods per plant, total dry matter in R6 as well as seed yield and protein content. Co-inoculation with Rhizobium and PGPR demonstrated a significant increase in the yield and yield components. The results showed that all treatments of bacteria increased yield; however, strains Rb-133 with P. fluorescens P-93 gave the highest seed yield, number of pods per plant, weight of 100 seed, seed protein yield, number of seed per pod, and seed protein yield. © 2010 Academic Journals. Source

Soleimani R.,Soil and Water Research Institute
Journal of Plant Nutrition | Year: 2010

This research was carried out to determine the effects of rate and time of nitrogen (N) application on safflower in a calcareous soil. The nitrogen rates were 50, 75, 100, 125, and 150 kg ha -1 and three split application methods were used. Experimental treatments were conducted as a factorial in a randomized complete block design (RCBD) with three replications. Duncan's Multiple Range Test (DMRT) indicated that the three split application of 100 kg ha -1 of nitrogen in stages of sowing date, early stem elongation, and early flowering had higher grain yield (2627 kg ha -1) than other treatments. This result was forecasted by results of increases in number of heads per square meter (heads m -2), number of grains per head (grains/head), and thousand grain weight (TGW). The highest oil yield was 755 kg ha -1 with the 100 kg ha -1 nitrogen application and was 727 kg ha -1 in treatment of three split application. © Taylor & Francis Group. Source

Siavoshi F.,University of Tehran | Asgharzadeh A.,Soil and Water Research Institute | Ghadiri H.,University of Tehran | Massarrat S.,Tehran University of Medical Sciences | And 2 more authors.
International Journal of Medical Microbiology | Year: 2011

The frequency of Helicobacter pylori vacA alleles, cagA, and jhp0947 and their association with types and advanced forms of gastritis in 143 first-degree relatives of gastric cancer (GC) patients was assessed. The subjects included 64/143 with antral-predominant gastritis, 68/143 with pangastritis, and 11/143 with corpus-predominant gastritis, with or without atrophy or intestinal metaplasia (IM). Further classification included the severity of atrophy or IM. Group I (40/143) included the subjects with moderate-marked atrophy or IM, group II (58/143) those with no atrophy or IM, and group III (45/143) with mild atrophy or IM. The frequency of vacA s1 was 79.7%, vacA s2 20.3%, m1 49.7%, m2 50.3%, cagA 76.2%, and jhp0947 58%. The most prevalent combination was vacAs1 cagA (+) (65.7%) (P= 0.001). Of the 143 subjects, 85 (59.4%) showed atrophy or IM, and 40/85 (47%) developed the moderate-marked atrophy or IM. No significant correlation was found between genotypes and the types of gastritis, non-atrophy, atrophy, or IM and severe forms of atrophy or IM (P> 0.05). It is proposed that H. pylori genotype status might not be considered as an important determinant of the types and advanced forms of gastritis in the first-degree relatives of GC patients. © 2011 Elsevier GmbH. Source

Ghorbanpour M.,Arak University | Hatami M.,Arak University | Khavazi K.,Soil and Water Research Institute
Turkish Journal of Biology | Year: 2013

This study examined the effects of inoculation with 2 rhizobacteria strains, Pseudomonas putida (PP) and Pseudomonas fluorescens (PF), on growth parameters, chlorophyll, proline, leaf relative water content (RWC), antioxidant enzyme activities (including superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT)), tropane alkaloids (such as hyoscyamine (HYO) and scopolamine (SCO)), and production of Hyoscyamus niger under 3 water deficit stress (WDS) levels, i.e. 30% (W1), 60% (W2), and 90% (W3) water depletion of field capacity. The results showed that inoculation with PP and PF strains minimized the deleterious effects of WDS on growth parameters. The activities of SOD and POX in root and leaf were increased to a significant extent with inoculation of PP and PF, and also with WDS treatment, whereas CAT activity decreased with increasing WDS, except for in plants treated with the PF strain. The maximum proline, HYO, and SCO content were recorded in PF-treated plants under W3 conditions. In contrast, the highest root and shoot alkaloids yield were obtained in plants bacterized with PP against W1 conditions. PP was the most effective strain under low WDS, PF had the highest efficiency in improving the growth and alkaloid production in the presence of severe (W3) WDS. Integrative use of effective plant growth promoting rhizobacteria (PGPR) and WDS could be an encouraging and eco-friendly strategy for increasing alkaloid yield and content in Hyoscyamus niger organs. © TÜBİTAK. Source

Zarea M.J.,Ilam University | Hajinia S.,Ilam University | Karimi N.,Ilam University | Mohammadi Goltapeh E.,University of Tehran | And 2 more authors.
Soil Biology and Biochemistry | Year: 2012

Salinity toxicity is a worldwide agricultural and eco-environmental problem. The intent of this study was to determine the salt tolerance of Piriformospora indica and strains of Azospirillum, isolated from non-saline and saline soil, as well as to determine their affect on the tolerance of wheat to soil salinity. In this study, an experiment was conducted to investigate the salt stress tolerance abilities of the endophytic fungi, P. indica, and Azospirillum strains, isolated from non-saline and saline soil, at five NaCl levels (0, 0.1, 0.2, 0.3, 0.4, 0.5 mol L -1). Additionally, a greenhouse experiment was conducted to test the effects of these selected microorganisms under increasing salinity levels on seedling growth, solute accumulation (proline and sugars), and photosynthetic pigments (Chl a, b, ab) of seedling wheat. Azospirillum strains were isolated in Iran from the root of field-grown maize from non-saline soil with an EC = 0.7 dS m -1 and from saline soil with an EC = 4.7 dS m -1. Plants were irrigated with non-saline water-tap water with an electrical conductivity water (ECw) value of 0.2 dS m -1, as well as low, moderate and severe saline water-irrigation with saline water with an ECw of 4 dS m -1, 8 dS m -1 and 12 dS m -1, respectively. The upper threshold of P. indica salinity tolerance was 0.4 mol L -1 NaCl in both liquid and solid broth medium. The upper thresholds of the salt adapted and non-adapted Azospirillum strains were 0.2 and 0.4 mol L -1 NaCl, respectively. The results indicated a positive influence of the organisms on salinity tolerance, more with the saline-adapted Azospirillum strains than the non-adapted strains. P. indica was more effective than the Azospirillum strains. These results could be related to a better water status, higher photosynthetic pigment contents and proline accumulation in wheat seedlings inoculated with P. indica. The benefits of both isolates and P. indica depended on two factors: water salinity and growth stage of the host plant. Inoculation with the two isolates increased salinity tolerance of wheat plants; the saline-adapted Azospirillum strains showed better performance with respect to improved fresh and dry weights at 80 and 100 days after sowing under both non-saline and saline conditions. When compared to plants inoculated with non-saline-adapted Azospirillum strains, those inoculated with adapted Azospirillum strains had much better performance with respect to the presence of photosynthetic pigment (Chl a, b and ab) and proline accumulation. Overall, these results indicate that the symbiotic association between P. indica fungus and wheat plants improved wheat growth, regardless of the salinity. It is concluded that the mechanisms for protecting plants from the detrimental effects of salinity by P. indica fungus and Azospirillum strains may differ in their salinity tolerance and influence the uptake of water, photosynthetic pigment contents and proline accumulation in wheat seedlings. © 2011 Elsevier Ltd. Source

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