Improvement of some morphological, biochemical and phenyl alanine ammonia lyase activity under effect of Karrikin, salicylic acid and humic acid in Lisianthus (Eustoma grandiflorum cv."Mariachi")

In recent years, in the world and in Iran as well, attention to Lisianthus flowers has been such that its production has increased significantly. With the increase in the production of Lisianthus cut flowers, attention to nutrition and application of treatments to improve the growth and storability of this flower is felt more than ever. For this purpose, the effect of karrikin, salicylic acid and humic acid on the morphological and biochemical characteristics of Lisianthus was investigated in a factorial experiment in a completely randomized design with three replications. The studied treatments included application of karrikin (0, 1 and 2 mg.l-1) as irrigation, salicylic acid (0, 100 and 200 mg.l-1) and humic acid (0, 50 and 100 mg.l-1) as foliar application. The results showed that the application of salicylic acid 100 mg.l-1 had the greatest effect on morphological and biochemical parameters, meanwhile, in some traits such as shoot dry weight and leaf area, a concentration of 200 mg.l-1 was more effective. Also, the use of humic acid increased the leaves and roots fresh and dry weight by increasing root expansion. karrikin treatment 1 mg.l-1 increased the number of leaves, stem length and diameter and number of flowering stems, fresh and dry weight of roots, number of seed capsules and number of buds per branch. karrikin in combination with humic acid and especially salicylic acid with synergistic effect improved some parameters such as number of roots and leaves and flowering stems and the activity of phenylalanine ammonialyase (PAL). Concomitant use of salicylic acid 100 mg.l-1 with humic acid 50 mg.l-1 as foliar application and application of Karrikin 1 mg.l-1 as a plant solution is recommended to improve growth parameters and the quality of lisianthus flowers.