جستجوی مقالات مرتبط با کلیدواژه "تلقیح میکروبی" در نشریات گروه "باغبانی"

 The use of intercropping and the potential of microorganisms such as Arbuscular mycorrhizal fungi (AMF) and Plant growth promoting rhizobacteria (PGPR) is one of the important strategies in sustainable agriculture. Intercropping is multiple cropping systems, in which two or more crop species planted simultaneously in a field during a growing season. Of course, this does not mean that in the intercropping, plants can be planted at a time together, but is the purpose that two or more crops are together in one place, during their growing season or at least in a time frame. Therefore, it is possible that plants are different in terms of planting date, and a plant is planted after the other plant. Potential benefits of intercropping are such as high productivity and profitability, improvement of soil fertility, efficient use of resources, reduction in the damages caused by pests and weeds, better lodging resistance and yield stability. On the other hand, the use of AMF and PGPR as biofertilizers can play a role in improving plant nutrition, plant growth and product quality. The aim of this study was to study the effect of AMF and PGPR inoculation on plant growth indices in bean-Moldavian balm intercropping.

 This experiment was conducted in the Agricultural Research Greenhouse of Urmia University, Located in 11 kilometers Sero road of the city of Urmia, Iran (latitude 36° 57′ N, longitude 45° 24′ E and 1321 m elevation) in 2017. The climate of the area is a Hot-summer Mediterranean climate bordering continental climate with cold winters, mild springs, hot dry summers, and warm autumns. This experiment was carried out in a factorial based on a randomized complete block design with three replications. The factors including microbial inoculation {(AMF, PGPR, AMF+PGPR and without microbial inoculation) and planting patterns (Sole cropping of Moldavian balms and bean, 1 row bean+ 1 row Moldavian balms (1:1), 2 rows bean+ 1 row Moldavian balms (2:1), 1 row bean+ 2 rows Moldavian balms (1:2) and 2 rows bean+ 2 row Moldavian balms (2:2)}. For this purpose, soil samples were prepared from Naqhadeh city in West Azerbaijan Province in Iran. In order to greenhouse tests, the soils added to the pots (in each pot containing 45 kg of soil). In treatments, soil used with microbial inoculation. Microbial strains were used for microbial inoculation including PGPR (P. aeruginosa, P.fluorescens and P. putida) and AMF (Funneliformis mosseae, Rhizophagus irregularis and Claroideoglomus etunicatum). For plant cultivation, been (Phaseolus vulgaris L.) and moldavian balms (Dracocephalum moldavica) seeds cultivar were grown in pots. At the end of the growth period, the characteristics of the agronomic traits in the bean plant were including plant height, number of seeds per pod, 1000 seed weight, biomass yield and Seed yield, and in Moldavian Balm were including, plant height, biomass yield and essential oil percentage were determined. In addition, the land equivalent ratio (LER) was calculated to determine the advantages of intercropping. The analysis of variance for the obtained data was done by statistical analysis system (SAS 9.4) software. The mean comparison was done using the Duncan test at the 5% probability level.

 The results showed that the different intercropping and microbial inoculation had a significant effect on all traits, in Moldavian balms and common beans. All the plant growth indices in common bean-Moldavian balm intercropping were the highest in the combined treatment of AMF +PGPR, compared to another treatment. The highest and the lowest seed and biomass yield of bean were achieved in sole cropping with 3.20 and 9.70 g and 1:1 with 1.57 and 4.41 g, respectively. The maximum biomass yield and other traits of Moldavian balm obtained under sole cropping, while essential oil percentage was higher in all intercropping patterns than in sole cropping patterns. The main constituents of Moldavian balms essential oil were Geranyl acetate, Geranial, Geraniol and Neral. The highest LER value (1.67) was obtained from 2:2 intercropping in PGPR inoculation.

 In general, the results showed that all of the plant growth indices of Moldavian balms and bean in sole cropping were higher than other intercropping patterns; however higher LER was observed in intercropping with microbial inoculation. This shows more exploitation of unit area in intercropping. In addition, the greater amount of LER in replacement intercropping than additive intercropping highlights the necessity of appropriate density of plants per unit area in the intercropping. It can be concluded that application of intercropping with combined application of AMF and PGPR leads to improvement on yield and yield components of plant.

This study was carried out to isolate and identify plant growth-promoting rhizobacteria (PGPR) from saline soils and to evaluate the effect of isolated rhizobacteria, as well as symbiotic and endophytic fungi on the concentration of some nutrient elements in wheat plants under salinity stress in greenhouse conditions. Factors included microbial treatments (rhizobacteria, mycorrhizal fungi, endophytic fungus, and control) and salinity levels (no salinity, 8 and 14 dS m-1). At the end of the growth period, the concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe), zinc (Zn) and manganese (Mn) in the shoot of the wheat plant, as well as the percentage of root colonization were measured. Based on growth-promoting trails, three isolates among the ten purified rhizobacteria were selected for phenotypic and molecular identification. Two identified isolates belonged to Pseudomonas genus (Pseudomonas aeruginosa Ur743 and Pseudomonas fluorescens Ur745), and the last one was Stenotrophomonas maltophilia Ur840. When the concentrations of nutrient elements were at the non-salinity level, mycorrhizal fungi were better than other microbial treatments in terms of absorbing P, Fe, and Mn, However, at the highest salinity level (i.e., 14 dS m-1), rhizobacteria significantly improved concentrations of N, P, Fe, and Mn in the plant shoot, compared to the control. Besides, the PGP bacteria increased the concentrations of K and Zn, as well as K:Na ratio by 1.99, 1.71, and 1.37 times, respectively, as compared to the control. In general, native microorganisms isolated from saline soil, as compared to other microorganisms in this study, improved the nutrient uptake and increased the wheat plant biomass under salinity stress.

Zinc (Zn) deficiency is one of the most widespread micronutrients deficiencies in plants that causes severe reduction in their growth and yield. An increase in reactive oxygen species (ROS) levels and a decrease in efficiency of detoxification mechanisms may be the major reasons for impairment of various cellular functions in Zn-deficient plants. This study was conducted in order to investigate the effects of individual and simultaneous inoculation of endophytic fungus, Piriformospora indica, and plant growth-promoting rhizobacterium, Azotobacter chroococcum, on biochemical properties, antioxidant enzyme activities and growth of wheat plant (Niknejad cultivar) in Zn deficiency and sufficiency conditions. The experiment was conducted in greenhouse of the Soilless Culture Center of Isfahan University of Technology by using the sterile sand-perlite (2:1 v/v) medium, as factorial in a completely randomized design with three replications. The results showed that Zn deficiency decreased shoot dry weight, carotenoid's content, total amount of Zn in shoot and antioxidant enzyme activities in control treatment (plants were not inoculated with fungi and bacteria). Inoculation of individual and simultaneous of P. indica and A. chroococcum resulted in increase of shoot dry weight at Zn deficiency condition. However, the highest shoot dry weight belonged to individual inoculation of A. chroococcum. Inoculated plants with P. indica had the highest total amount of Zn in shoot and concentration of carotenoids at both levels of Zn. Whereas, individual inoculation of A. chroococcum and also in combination with P. indica had only significant effect on increasing the total amount of Zn in shoot at Zn deficiency condition. Inoculation of A. chroococcum alone and also in combination with P. indica resulted in inducing antioxidant enzyme activities of ascorbate peroxidase and peroxidase in response to Zn deficiency. Whereas, individual inoculation of P. indica resulted in increasing and decreasing the activities of peroxidase and ascorbate peroxidase, respectively. In general, inoculation of wheat plant (Niknejad cultivar) with the studied microorganisms in this research, particularly inoculation of A. chroococcum, can serve as a useful method for alleviating deleterious effects of Zn deficiency stress.