Evaluating the Yield, Fatty Acid Composition, and the Seed Micronutrients Content in Peanut Cultivars under the Influence of Various Rates of Sulfur and Zinc Application

To investigate the effect of sulfur (S) and zinc (Zn) fertilizers on yield, fatty acid composition, and micronutrients of two peanut cultivars, a factorial experiment in a randomized complete block design with three replications was conducted in a farm in Guilan province, Astana Ashrafieh city in 2019 and 2020. The effects of S and Zn on peanut seed yield, fatty acids, and micronutrients were significant at the 1% level. The simultaneous application of Zn foliar application at a rate of 2 per thousand and S fertilizer at a rate of 40 kg ha^-1 produced the maximum grain yield of the Spanish cultivar (with an average of 5770 kg ha^-1). With an average of 5331 kg ha^-1, the North Carolina 2 (CN2) cultivar produced the maximum yield when treated with 60 kg ha^-1 of S and Zn foliar application at 2 per thousand. In terms of the number of fatty acids that make up the oil structure based on the average of the treatments tested, Oleic acid (56.9% in the Spanish cultivar and 61.1% in the CN2 cultivar) and Linoleic acid (28.6%) had the highest amount. The highest amount of palmitic acid was significantly higher in the treatment of the application of 40 kg ha^-1 of S with a foliar application at 2 per thousand Zn (8.8%) and the lowest amount was found in the treatment without S and Zn (7.2%). According to the results of this experiment, both S and Zn factors were effective on most traits, so it is better to use Zn fertilizer if S is used to better absorb this element and can be effective in the growth and development of peanut plants. Therefore, simultaneous use of S fertilizer and Zn foliar application at high levels to improve the quality of fatty acids and grain micronutrients in the Guilan region is recommended.