Effects of biofertilizers and iron nano-oxide on maize yield and physiological properties under optimal irrigation and drought stress conditions.

In this research, effects iron nano-oxide and biofertilizers and chemical was investigated on the yield and some traits of Maize under normal and drought stress conditions in two years (2018 and 2019). The experiment was performed in the form of split-spilt plot in a complete random block design with three replications. The studied irrigation treatment included three levels (normal, 85% and 65% optimum water requirement) in the main plots and iron nano-oxide at four levels (0, 0.5, 1, and 1.5 g/L) in subplots, and biofertilizers at four levels (noninoculation, inoculation with mycorrhiza, inoculation with pseudomonas and combined inoculation of mycorrhiza and pseudomonas) in sub-plots. The results showed that grain yield, 1000-grain weight, and leaf chlorophyll contents decreased by drought stress. Use of pseudomonas and mycorrhiza increased these traits in normal and stress conditions, but iron nano-oxide had no significant effect on the measured traits. Also, drought stress increased malondialdehyde, ion leakage, catalase, peroxidase, proline, and polyphenol oxidase in both light and severe stress regimes. The amount of antioxidant enzymes increased under drought stress conditions in corn. The results indicated that all the characteristics measured by double inoculation with Pseudomonas and Microoriza had the best performance in conditions of water shortage and the use of these biofertilizers increases yield, 1000-seed weight, and chlorophyll content of maize. Also, the use of biofertilizers modulates the effect of drought stress and reduces its negative effects.

Evaluation of interaction between Piriformospora indica, animal manure and NPK fertilizer on quantitative and qualitative yield and absorption of elements in sunflower.

Microbial endophytes are considered as one of the most important soil microorganisms which increase their yield per unit area by generating genetic, physiological, and ecological changes in their host plants. We conducted an experiment as factorial in a completely randomized manner with three replications at the Ghasre Shirin greenhouse of Kermanshah province in order to evaluate the interaction of Piriformospora indica (inoculation-noninoculation) with manure (25% of the flowerpot volume-without using manure as a control) and NPK chemical fertilizer (10 g per flowerpot-without the use of fertilizer as a control), the quantitative and qualitative yield and absorption of elements in sunflower. The results showed that the interaction of P. indica, manure, and chemical fertilizer on the colonization percentage, seed oil percentage, nitrogen concentration, phosphorus concentration, and the 1000-seed weight was significant at 1% probability level, and on yield index, growth, plant height, and concentration of potassium element it was at 5% probability level. Bilateral effects of P. indica with chemical fertilizer and the manure treated with chemical fertilizer on the budding time were significant at the probability level of 1% and 5%, respectively. It seems that the coexistence between sunflower root and P. indica increases the growth of the root system of the plant; thereby it increases the height of plant because of the absorption of essential elements such as nitrogen, phosphorus, and potassium by the root, and increases the quantitative and qualitative yield of sunflower.