Effect of application of Ca, S, Mg and urea on growth, yield and chemical composition of Nigella sativa L. plants

This work was carried out at the Experimental Farm of Fac. of Agriculture at Moshtohor, Benha Univ. for two successive seasons (2003/2004 and 2004/2005). It aimed to study the effect of foliar spray with some nutrient elements (calcium, sulfur, and magnesium) at the rate of 200ppm plus control combined with urea at rates of 0.0, 0.5, 1.0 and 1.5% on vegetative growth, seed yield and chemical composition of Nigella saliva plants. A split plot design with three replications was used. Urea levels occupied in the main plots and those calcium, sulfur, and magnesium plus control were allocated at random in the sub plots. Plant growth parameters such as plant height, number of branches, fresh and dry weights of herb/plant, seed yield/plant and per feddan were recorded and seed quality was estimated by measuring volatile and fixed oils percentage as well as the main components of the volatile oil. Herb was chemically analyzed to determine N,P,K and tot al carbohydrates percentages. The obtained results showed that foliar spraying of Nigella saliva plants with each of urea or calcium, sulfur and magnesium elements increased the different parameters such as plant height, fresh and dry weights of herb/plant, number of capsules, seed yield/plant or per feddan and also increased each of volatile or fixed oils percentage in plant seeds as well as N,P,K and total carbohydrates percentages in plant herb compared with control treatment in both seasons. Also, all interaction treatments between the different levels of urea and each of calcium, sulfur or magnesium elements attained significant increase in growth and seed yield characters and also caused a relative increase in seeds content of volatile and fixed oils percentage as well as N,P,K and total carbohydrates percentage in plant herb compared with control treatment. The highest values of seed yield/plant or/feddan as well as volatile and fixed oil percentages were resulted fro m the application of urea at the rate of 1.5% + Mg at the rate of 200 ppm. The G.L.C. determination revealed the presence each of oc, and P pinene, limonene, borneol and the thymoquinone compounds of volatile oil of seeds. Spraying plants with Mg + urea at the rate of 0.5% gave the highest value of thymoquinone compound in the volatile oil compared with all other treatments.