Effects of kitchen waste compost and chemical fertilizer application on spinach (Spinacia oleracea L.) c.v. Matador plant growth and nitrate accumulation

Abstract

In this study, the effects of organic and chemical fertilizer sources on some essential nutrient elements content, nitrate (NO3--N) accumulation, and the growth of spinach plant (Spinacia oleracea L.) were investigated. The experiment was carried out in a randomized plot design under greenhouse conditions, with two levels. 1st level; applications with chemical fertilizer. 2nd level; applications without chemical fertilizer. One compost material (kitchen waste compost = KWC), five different doses (0, 0.4, 0.8, 1.2, and 1.6%), and three replications. For chemical fertilization, nitrogen (N) dose of 150 kg ha(-1) was applied by using 15-15-15 NPK (N:P2O5:K2O) fertilizer. Overall, KWC applications increased plant growth and nutrient content. However, the most significant increases occurred in the trial subjects where chemical fertilizer and KWC were applied together. The use of KWC together with chemical fertilization increased the leaf width, leaf and stem length, fresh weight, and dry weight, as well as nitrate accumulation, N, potassium (K), and iron (Fe) content of the plant. The highest values of these parameters were obtained at 0.8% dose of KWC + NPK medium. As a result, compost applications were effectively uptake of nutrients and nitrate accumulation remained at acceptable values.