Abstract
To distinguish the impacts of soil moisture conditions and the foliar spraying with an amino acid as affected by two organic inputs on the dry matter yield and volatile oil of sage (Salvia officinalis L.) at the early flowering stage, a field experiment was done according to a split-plot in time and place design in West of Iran in two experimental years. Experimental treatments were two irrigation frequency levels [optimum or irrigation at field capacity (F.C.) and reduced irrigation or irrigation at 50% F.C.] as the main plot, and in subplots: organic inputsin three levels including control (without amendment), arbuscular mycorrhizal fugi (AMF), and cow dung manure, and also the foliar spraying of L-phenylalanine amino acid at four levels: negative control (non-spraying), positive control (with distilled water as solvent), and foliar spraying with 25 and 50% L-phenylalanine. Results indicated that the basic compounds of the volatile oil from sage were oxygenated monoterpenes, including 1,8-cineole, camphor, α-thujone, and β-thujone. Generally, the highest values of these oxygenated monoterpenes were obtained from optimum irrigation and foliar spraying with amino acids (50% L-phenylalanine) under an organic farming system, which significantly influenced the quantity and quality of the biologically active compound of sage. In addition, the highest value of dry matter yield (972.97 g m− 2) was observed in the second experimental year in the interaction of 50% L-phenylalanine × 100% F.C. × cow dung manure, and also 943.52 g m− 2, was seen in the first year in the 50% L-phenylalanine × 100% F.C. × mycorrhizal symbiosis. Generally, the foliar spray of amino acids under organic inputs (AMF and cow dung manure), and their interaction could ameliorate the dry matter yield and essential oil compounds of sage in environmentally friendly agriculture conditions.