Effect of nitrogen fertilizer and vermicompost application on agronomic characteristics, seed yield and quality of sesame (Sesamum indicum L.)

One of the pillars of a sustainable agricultural system is the use of organic fertilizers to provide the nutrients needed by the plant with the aim of eliminating or significantly reducing the consumption of chemical inputs (Darzi et al., 2011). Organic fertilizer includes vermicompost and products from the activity of phosphate-solubilizing microorganisms and stabilizers of nitrogen or other nutrients that are active in the soil (Anwar et al., 2005). Sesame is an old and important oilseed crop that is usually grown on small farmers' tropical and subtropical farms (Weiss et al., 2000). This study was conducted for investigating the effect of different levels of nitrogen fertilizer, vermicompost and their combined application on sesame plant of single branch cultivar in Tarom region of Zanjan province.

Experiment in a complete randomized block design was carried out with three replications in Tarom, Zanjan province, Iran during cropping seasons of 2016-2017. Treatments consisted of four levels of nitrogen fertilizer (0, 30, 60 and 90 kg Nitrogen ha-1) and integrated nitrogen of chemical and organic (15 kg N ha-1 + 2.5 ton ha-1 vermicompost, 30 kg N ha-1 + 5 ton ha-1 vermicompost and 45 kg N ha-1 + 7.5 ton ha-1 vermicompost) and vermicompost (5, 10 and 15 ton ha-1) were used.

Results showed that use of nitrogen fertilizer, vermicompost and combination nitrogen fertilizer and vermicompost had significant effect on seed yield and yield components of sesame. So that, Maximum plant height, number of capsule in plant, number of seed.plant-1, 1000-seed weight and seed yield (3087.87) were obtained 45 kg N ha-1 + 7.5 ton ha-1 . Maximum biological yield (8360 kg ha-1) was obtained using the treatment 45 kg N ha-1 +7.5 ton ha-1 vermicompost. Also, seed oil percentage was not affected by any of the treatments; As a result, Maximum oil yield (1530.36 kg ha-1) was obtained using treatment 30 kg N ha-1 + 5 ton ha-1.