Elements concentration, seed and essential oil yield of Thorn apple (Datura stramonium L.) under direct, cumulative and residual effects of organic and conventional agricultural systems

In order to replace the chemical inputs with ecological compatible inputs, an experiment was conducted on split plot based on a randomized complete block design with three replications, at the Research Station of Bayakola during two years (2016 and 2017). Experimental treatments were plant nutrition with NPK, animal manure, compost, vermicompost and control (no chemical and organic fertilizer) as main plot and biophosphate, nitroxin, nitroxin + bio-phosphate, nano biumik and control (no bio and nano bio-fertilizer) as subplot. Interactions of organic and inorganic, bio and nano bio-fertilizer treatments and nutritional systems (direct, cumulative and residual) on all studied traits were significant (P≤0.01). In all three nutritional systems the highest amounts of leaf and grain nitrogen concentration, copper, manganese, zinc, iron and calcium elements concentration of leaves, leaves dry weight, grain yield and essential oil perecentage and yield, were obtained in vermicompost in combination with nano biumik fertilizers, the highest amounts of leaf and grain phosphorus and potassium concentration were obtained from combining animal manure with nano biumik fertilizers and the maximum amount of leaf magnesium was obtained from the combination of compost and nano biumik treatments. There was no significant difference between fertilization systemes. Therefore, with respect to the production of medicinal plants in the low-input cropping systems, using a load of combinations of organic (especially vermicompost) and nano biumik fertilizers for two consecutive years are recommended for improving elements concentration, seed yield and essential oil percentage and yield of datura.