mycorrhizal fungus

Due to high production and good economic income, greenhouse cultures are growing. Therefore, it is necessary to find methods that increase yield and water use efficiency in greenhouse conditions. Use of mycorrhiza fungi and hydrogel can be suggested in this regard. A factorial experiment was conducted in a completely randomized design with 3 replications in the greenhouse of Payame Noor University of Zahedan center in 2017-2018. The first experimental factor included irrigation at three levels of low, moderate and normal with 540, 790 and 1040 liters of water per square meter, respectively. The second factor consisted of mycorrhizal fungus at two levels of inoculation and no inoculation. Hydrogel treatment at two levels was considered as the third factor. The results showed that under normal irrigation conditions and combined application of fungus and hydrogel, the highest plant height, number of fruits per plant, final fruit yield, dry weight of shoot and root, relative leaf water content and water use efficiency were obtained. For the above traits, no significant difference was observed between this treatment and treatment of normal irrigation and fungal inoculation and without hydrogel application. At moderate irrigation condition, the highest values of the mentioned traits were obtained from the combined treatment of fungus and hydrogel and the yield obtained from this treatment was not significantly different from the one at normal irrigation condition without the use of fungus and hydrogel. At low irrigation condition, the highest values of the studied traits were obtained from combined treatment fungus and hydrogel and also application of hydrogel without the use of fungus. The lowest values of the studied traits in this experiment were obtained at low irrigation treatment without the use of fungus and hydrogel. At low irrigation condition, there was no significant difference between the two treatments of fungal application without the use of hydrogel and lack of fungal application which indicates that the fungus is not effective at low irrigation condition.

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.

To investigate the effect of integrative application of mycorrhizal fungus and chemical fertilizer on the quantitative and qualitative characteristics of medicinal plant dragon’s head (Lallemantia iberica Benth.) under rainfed conditions, an experiment was conducted as a randomized complete block design with seven treatments and three replications in the research farm of Maragheh University, Iran, in 2017. Treatments included 100% conventional chemical fertilizer (250 and 150 kg ha-1 urea and triple superphosphate, respectively), Glomus mosseae (GM), G. intraradices (GI), 50% chemical fertilizer+GM, 50% chemical fertilizer+GIand 50% chemical fertilizer+GI+GM. The results demonstrated that the highest (802.8 kg ha-1) and lowest (463.5 kg ha-1) seed yield and the highest (40.64%) and lowest (25.85%) harvest index were achieved in the integrative application of 50% chemical fertilizer+GI+GMand separate application of GI treatments, respectively. Besides, the highest content (9.18%) and yield (73.75 kg ha-1) of mucilage was observed in 50% chemical fertilizer+GI+GM treatment. Furthermore, the highest amount of mucilage compounds (glucuronic acid, galacturonic acid, arabinose, raffinose, galactose, glucose, xylose and rhamnose) was obtained in 50% chemical fertilizer+GI+GM treatment. Based on cluster analysis, the treatments were divided into three groups. In general, the application of 50% chemical fertilizer+GI+GM while reducing the use of chemical fertilizers improved the quantitative and qualitative yield of the dragon’s head.