Univrsity of Tehran Press Iranian Journal of Field Crop Science 2008-4811 53 1 2022 03 21 Effect of some of growth stimulants and different levels of chemical fertilizer on yield and yield components of maize Effect of some of growth stimulants and different levels of chemical fertilizer on yield and yield components of maize 189 200 87865 10.22059/ijfcs.2021.320634.654812 FA Hashem Ebrahimi Department of Agronomy, Karaj Branch, Islamic Azad University, Karaj, Iran Mohammad Nabi Ilkaei Department of Agronomy, Karaj Branch, Islamic Azad University, Karaj, Iran. Mohamadmehdi Tehrani Soil and Water Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran Farzad Paknejad Department of Agronomy, Karaj Branch, Islamic Azad University, Karaj, Iran. 0000-0003-0951-2072 Majid Basirt Soil and Water Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran Journal Article 2021 03 19 In order to evaluate the effect of plant growth stimulants and levels of chemical fertilizer on yield and yield components of corn, a factorial field experiment was conducted based on randomized complete block design with three replications and 21 treatments at research field of Soil and Water Research Institute (SWRI), Karaj, Iran, during 2019. The studied factors included different levels of fertilizer (application of 100% fertilizer required by the plant, application of 75% fertilizer required by the plant, and no fertilizer (control)) and different growth stimulants (foliar application of amino acid, seaweed and fulvic acid, humic acid fertigation, humic acid fertigation + foliar application of seaweed + amino acid, and no growth stimulants (control)). The results showed that the highest straw and biological yields were obtained from 75% fertilizer application with seaweed foliar application treatment, so that they were 10.33% and 11.85% more than the control, respectively. Also, 100% application of chemical fertilizer and humic acid fertigation, 100% chemical fertilizer application with combination of humic acid fertigation + seaweed foliar + amino acid foliar, and 75% chemical fertilizer application with seaweed foliar application treatments, produced 27%. 57%, 24.60%, and 23.83% grain yield higher than the control. According to the results of this experiment, not only seaweed application improved the yield, but also reduced the use of chemical fertilizers required by 25% without reducing the yield of the plant. Therefore, seaweed foliar application is recommended. In order to evaluate the effect of plant growth stimulants and levels of chemical fertilizer on yield and yield components of corn, a factorial field experiment was conducted based on randomized complete block design with three replications and 21 treatments at research field of Soil and Water Research Institute (SWRI), Karaj, Iran, during 2019. The studied factors included different levels of fertilizer (application of 100% fertilizer required by the plant, application of 75% fertilizer required by the plant, and no fertilizer (control)) and different growth stimulants (foliar application of amino acid, seaweed and fulvic acid, humic acid fertigation, humic acid fertigation + foliar application of seaweed + amino acid, and no growth stimulants (control)). The results showed that the highest straw and biological yields were obtained from 75% fertilizer application with seaweed foliar application treatment, so that they were 10.33% and 11.85% more than the control, respectively. Also, 100% application of chemical fertilizer and humic acid fertigation, 100% chemical fertilizer application with combination of humic acid fertigation + seaweed foliar + amino acid foliar, and 75% chemical fertilizer application with seaweed foliar application treatments, produced 27%. 57%, 24.60%, and 23.83% grain yield higher than the control. According to the results of this experiment, not only seaweed application improved the yield, but also reduced the use of chemical fertilizers required by 25% without reducing the yield of the plant. Therefore, seaweed foliar application is recommended. https://ijfcs.ut.ac.ir/article_87865_bda464ce371c627866511f03f83a3d83.pdf