Application of Eruca sativa Mill. for organic fertilization and spraying with arginine, their effects on growth characteristics and seed yield along with identifying their content of some medically effective compounds

A field experiment was conducted during the 2018-2019 season in one of the private fields in Karma City, Anbar Governorate, Iraq to study the effects of organic fertilizer levels (0, 5 and 10 tons ha^-1) and spraying with amino acid arginine at concentrations of 0, 100, 200 mg L^-1 on growth and also yield characteristics in addition to some medicinally-active compounds in watercress seeds, Eruca sativa Mill. The study factors were arranged as split-plot experiment according to the randomized complete block design (RCBD), with three replications. According to the results, the fertilizer level at 10 tons ha^-1 exhibited a significant elevation in the characteristics of growth, yield, oil rate (%), and seed contents of glucosinolate glycoside and Astragalin alkaloid, whereas spraying arginine at 200 mg L^-1 showed significant differences in the characteristics of yield, oil rate (%), and seed content of glucocinolate glycoside and Astragalin alkaloid. In addition, the interaction of the studied characteristics displayed a significant effect. So that, the plants given 10 tons ha^-1 of organic fertilizer under the influence of spraying with 200 mg L^-1 arginine, revealed the highest rate of 1000-seed weight, oil rate (%), in addition to the seed content of glucocinolate glycoside and Astragalin.