Effects of vermicompost and nitrogen-fixing bacteria on growth and chemical compounds of Sesame (Sesamum indicum L.)

Nowadays, the use of chemical fertilizers in agricultural land causes numerous environmental problems such as water pollution, soil pollution and reduction of soil fertility. Using biological resources have important role in soil biological activity and fertility, improvement of product quality and safety of agricultural ecosystems. Hence, to investigate the effects of vermicompost and nitrogen-fixing bacteria (NFB)on the growth and nutrient uptake of Sesame seedlings, a greenhouse experiment was conducted in completely randomized factorial design with four replications. Treatments were included four levels of vermicompost (zero (V0), 1 (V1), 2 (V2) and 4 percent (V3)) and three levels of bacterial treatments (inoculation with Azospirillum (B1) and Azotobacter (B2) and without bacteria (B0)). The results showed that the application of vermicompost and NBF, each one alone, significantly increased the plant height, stem diameter, phosphorus and zinc uptake. Also, simultaneous application of vermicompost and NFB significantly enhanced shoot dry weight, leaf surface area and uptake of nitrogen, phosphorus, potassium, iron, manganese and copper. The maximum shoot dry weight, leaf surface and uptake of nitrogen, potassium, iron and manganese were obtained from 4 % vermicompost treatment with Azotobacter inoculation. The highest copper content in the shoot was found in 2% vermicompost treatment without bacteria inoculation.