Choose a Planting Substrate and Fertilization Method to Achieve Optimal Growth of Araucaria excelsa

Due to the lack of scientific knowledge for the use of substrate and best fertilizing method in the growth of Araucaria excelsa, it is crucially important to find the most appropriate planting substrate and fertilizing method. The effect of conventional fertilizing method and the application of Fe nanofertilizer were studied on the growth of A. excelsa in which six fertilizing methods and three substrates were examined in a factorial experiment based on a Randomized Complete Design with three replications. The seedlings of A. excelsa were transferred to 4-L pots after the selection of substrate type and were placed in greenhouse at day/night temperature of 21-23/17-19°C. Some growth indices were recorded including plant height, lateral shoot length, stem diameter, root length, shoot and root fresh weight, shoot and root dry weight, total fresh and dry weight, and the concentrations of some nutrients in leaves. It was found that the substrate A3 (25% cocopeat + 25% vermicompost + 25% light soil + 25% perlite) was the most appropriate substrate for this plant in terms of most estimated traits (lateral shoot length, root fresh weight, root dry weight, total dry weight, and shoot P and Fe content). Among fertilizing compounds, the treatment B3 (Ferrilene + NPK (20-20-20) + diammonium phosphate + potassium sulfate + ammonium sulfate) was found to be superior for some traits like lateral shoot length, shoot fresh weight, total fresh weight, shoot dry weight and total dry weight. It was revealed that the treatment A3B2 (25% cocopeat + 25% vermicompost + 25% light soil + 25% perlite) + diammonium phosphate, potassium sulfate and ammonium sulfate was the most appropriate treatment in terms of shoot and root fresh weight, total fresh weight and total dry weight. So, it is recommended to apply this treatment in the production of Araucaria excelsa.