Effect of spraying some bio and nano stimulants fortified with potassium on some qualitative traits and active substances in rice grain

The purpose of this study was to determine how rice (Anber 33 cultivar) responded to foliar spraying with individual and potassium-fortified bio and nano stimulants on various qualitative features and active ingredients in rice grains. During the time frame of 15 June 2021 to 23 November 2021, field research was carried out in (District 41 - Al-Hussainiya, Al-Tali’ah Sub-district), Babylon province, Iraq. Three replications of the experiment were carried out using the ” Randomized Complete Blocks Design ” (RCBD) (48 experimental units) The experiment consisted of 16 treatments that were randomly assigned to each replicator in accordance with a straightforward one-way experiment in which (7) bio and nano-stimulants, represented by Atonik, Fertigrain, Siaption, Cimfamin BK, Taravertavant, Nano Optimus plus, and Saccharmyces cerevisiae extract, were sprayed separately and supplemented with potassium, in addition to the control treatment, which consisted of spraying only water, between treatments (14 days) there are two sprays every treatment. Duncan test results showed that foliar spraying with Fertigrain biostimulator supplemented with potassium (Fer+K) recorded the highest mean of (8.74) % of the protein in grains, iron concentration in grains (12.12) mg Fe kg−1, and copper concentration in grains (4.62) mg Cu. kg−1. Also, foliar spraying with Nano Optimus plus potassium (NOp+K) recorded the highest average of zinc concentration in grains (18) mg Zn kg−1. The results of the gas chromatography coupled with mass spectrometry (GC-MS) also showed that the Nano Optimus plus (NOp) treatment recorded the highest percentage in the rice grain content of saturated fatty acid stearic acid (8.4%) and spraying with the growth regulator Atonik (At) gave the highest value in the content of the rice grains. Rice grains of palmitic acid (34.05)% and the foliar spraying with Fertigrain and Potassium (Fer+K) stimulator recorded the highest level in the content of rice grains of the unsaturated fatty acid oleic acid (39.86)%, and that the treatment of Cifamin and potassium (Ci+K) gave the highest value of the content of rice grains of linoleic acid (45.15) %. The foliar spray with Fertigrain (Fer) stimulator excelled in giving the highest percentage of volatile oils (32.4%) and the foliar spray Atonik and Potassium (At+K) recorded the highest value of hydrocarbon compounds in rice grains (55.74 percent).