Enhancing Productivity of Sweet Marjoram in Substrate Culture

Sweet Marjoram is considered as one of the important herbal plants, grown in many countries for medical and nutritional purposes and is an abundant source of valuable biologically active substances and mineral components. An experiment has been carried out on sweet marjoram at the experimental site of Central Laboratory for Agricultural Climate (CLAC), Agriculture Research Center,  Ministry of Agriculutre and land reclamation, Egypt under a net duble span house, during seasons of 2019and 2020. The experiment was carried out to study the effect of different nutrient solution sources and verimicompost rates on production of Sweet Marjoram grown in sand culture. In this experiment, Three sources of nutrient solution were under investigation (chemical nutrient solution “CN. S.” as a control treatment, vermi-liquid “V. L.” and mixture of chemical nutrient solution andvermi-liquid (50%:50%) “CN.S.+V.L.”), also, five rates of vermicompost have been added to sand culture(zero% of vermicompost "V.C. 0%"as a control treatment, 10% Vermicompost "V.C. 10%", 20% Vermicompost "V.C. 20%", 30% Vermicompost "V.C. 30%"and 40% Vermicompost "V.C. 40%").Regarding the effect of nutrient solution source; results illustrated that chemical nutrient solution recorded the highest values for  vegetative growth, yield and chemical measurments. also data clearfied that the mixture of chemical nutrient solution and vermi-liquid (50%:50%) “CN.S.+V.L.” recorded a promising results very close to the chemical nutrient solution and more healther; because the amount of chemicals used in this nutrient solution have been reduced into the half amount only comparison with chemical nutrient solution. For that, the mixture of chemical nutrient solution and vermi-liquid (50%:50%) could be considered as the most suitable nutrient solution for sweet marjoram. Concerning the effect of different vermicompost rates, results showed that adding vermicompost rate by 30% to sand culture recorded the highest values for plant height,  number of branches /plant, Fresh and dry weights of the aerial parts /plant, yields of the fresh and dry herb/ m2, yield of aromatic oil/ m2 (V.C. 40% recorded higher values for yield of the aromatic oil/m2 than V.C. 30% but the difference between both of them was not significant), and N,P,K% in leaves.