How Does Immersion of saffron Corm in Some Hormones and Humic Acid Affect the Morphological Characteristics of Plant under Salinity Stress

The use of growth-promoting hormones and organic acids is one of the ways to deal with environmental stresses. The present study was conducted to assess the effect of these treatments on saffron vegetative and reproductive traits, to use organic inputs properly, take steps towards sustainable production and increase quality of important medicinal plant. Current research carried out via factorial experiment was conducted in Islamic Azad University, Isfahan (Khorasgan) Branch (2018-2019) in a completely randomized design with three replications. The treatments were control, Salicylic acid (1 and 2 mM), humic acid (15 and 30 mM) and Jasmonic acid (5 and 10 μM) with two salinity levels (1 and 4 ds.m-1). The evaluated traits included chlorophyll a, b and total chlorophyll, the number of flowers, flowering stem and leaves, petiole length, fresh and dry weights of leaves, stigma weight, and fresh weight of flowers. The highest levels of chlorophyll a and total chlorophyll were belonging to humic acid 30 and control treatments under salinity 1. The highest amount of chlorophyll b was observed in humic acid 30 and control treatments under salinity 1 and salicylic acid 2 under salinity 4. The highest number and fresh weight of flowers were obtained from the control treatment under salinity 1. The tallest petioles and flowering stems were observed in Jasmonic acid10 under salinity1. The highest leaf length was belonging to salicylic acid2 under salinity1. The highest leaf fresh weight was belonging to salicylic acid2 under salinity1 whereas of Humic acid15 under salinity1 produced the highest dry weight of plant leaves. The highest stigma weight was observed in Jasmonic acid5 and the control under salinity1. As a result, application of plant growth regulators and humic acid can reduce effect of salinity stress in saffron. As a final conclusion of this study, it can be said that the use of growth-promoting hormones (salicylic acid) and organic acids (humic acid) under environmental stress conditions can improve morphological and vegetative characteristics such as chlorophyll and biomass produced in some plants such as saffron.