Effects of biofertilizers and foliar application of iron oxide nanoparticle on grain yield and some physiological characteristics of black cumin (Nigella sativa L.)

Abstract To study the effects of biofertilizers and foliar application of iron oxide nanoparticles on grain yield and some physiological characteristics of black cumin (Nigella sativa L.), an experiment was carried out as factorial in randomized complete block design with three replications at the growing season of 2017, in Agricultural College of Shahrood University of Technology. Treatments consisted of foliar application of iron oxide nanoparticles at three levels (control, 1.5 and 3 g/L water) as the first factor and biofertilizers at five levels (mycorrhizal fungi Glomus intraradices and Glomus mosseae and two types of growth promoting rhizobacteria including Azospirillum and Azotobacter solution with control) as the second factor. Results showed that the highest grain yield was obtained from inoculation with mycorrhizal fungus, Glomus intraradices .The interaction of foliar application of iron oxide nanoparticles and biofertilizers had a significant effect on antioxidant enzyme activities such as catalase, ascorbat peroxidase and polyphenol oxidase as well as total, “a” and “b” chlorophylls. The highest activity of catalase, ascorbat peroxidase and polyphenol oxidase enzymes were in 3 g/L water Iron oxide nanoparticles treatment of and non-use of biofertilizers. The highest amount of chlorophyll “a” was obtained from 3 g/L water treatment, with Glomus intraradices and chlorophyll “b” from the combination of two concentrations of iron nano oxide with two mycorrhizal fungi. It seems that among the treatments studied, Glomus intraradices had the highest effect on grain yield of the black cumin and application of 3 g iron nano oxide /L of water was highly effective in the photosynthetic pigmentation increasing and antioxidant enzymes activity.