EFFECT OF SOME AMINO ACIDS CONCENTRATION ON GROWTH AND YIELD OF LAVENDER (Lavandula officinalis, CHAIX) PLANT UNDER DIFFERENT NPK FERTILIZATION LEVELS

Abstract

Two field experiments were conducted at the experimental farm, Faculty of Agriculture, Zagazig University, Egypt during the two consecutive summer seasons of 2018 and 2019. They study aimed to investigate the effect of different NPK fertilization levels (0.0, 25, 50, 75 and 100% of recommended rate), amino acid concentrations (control, L-tryptophan acid at 50 and 100 ppm as well as phenylalanine acid at 150 and 300 ppm) and their interactions on growth and yield components of lavender (Lavandula officinalis, Chaix) plant. The NPK recommended rates (RR) were 61.5, 31 and 24 kg of N, P2O5 and K2O/faddan, respectively. The obtained results pointed out that the maximum value for each of plant height, number of branches/plant, fresh and dry weights of roots/plant and root length as well as fresh and dry weights of lavender herb/ plant and /faddan were recorded when lavender plants were fertilized with 100% RR of NPK. Also, increasing NPK fertilization levels gradually increased abovementioned parameters. Foliar spray with L-tryptophan at 100 ppm, significantly increased lavender growth parameters and yield components compared to spraying with the other amino acid concentrations and control (untreated plants), in most cases. Generally, the best interaction treatment in this connection was obtained by the treatment of 100% recommended rate of NPK and spraying with 100 ppm of L-tryptophan acid.