THE EFFECTS OF APPLICATION OF BIOLOGICAL FERTILIZERS AND DIFFERENT AMOUNTS OF UREA FERTILIZER SOURCES UNDER LOW WATER STRESS CONDITIONS ON PHYSIOLOGICAL TRAITS OF MEDICINAL PLANT (CALENDULA OFFICINALIS L.)

In order to evaluate the effect of application of biological fertilizers and different amounts of urea fertilizer under low water stress conditions on physiological traits of Calendula officinalis L. an experiment was conducted during two years of cultivation of 2015-2016 and 2016-2017 at the research farm of Islamic Azad University (IAU), Varamin-Pishva Branch, Iran. The experiment was split-split plot based on randomized complete block design with three replications. The experimental treatments included different levels of dehydration as the main factor in two levels (lack of water stress (control), irrigation interruption during boiling stage), levels of biological fertilizers in four levels as a sub-agent (no use of biological fertilizer, application of Azotobacter chroococcum, application of Azospirillum brasilense, combination of Azotobacter and Azospirillum), and urea fertilizer sources at four levels as a sub-subtype (non-consumption (control), recommended amount of urea fertilizer with sulphur coating, 75% of the recommended amount of urea fertilizer with sulphur coating was recommended as the most common form of urea fertilizer (157 kg/ha based on soil test). The results showed that irrigation in boiling stage increased activity of the enzyme di-hydroxy Guanuzyn, glutathione peroxidase, superoxide dismutase also, production of the total phenol, total flavonoid and biomarker of di-tyrosine. In this study, drought stress and application of Nitroxin fertilizer resulted in increased malondialdehyde in the first year. In both years, the application of Nitroxin with the recommended amount of urea fertilizer with sulphur coating resulted in an increase in total flavonoid and Glutathione Peroxidase enzymes. The purpose of this study was to investigate the effect of bacteria in the plant, along with the amount and sources of nitrogen fertilizer to reduce nitrogen fertilizer application on plant yield, as well as sustainable agriculture management through integrated nutrition in different plant conditions.