EFFECT OF IRRIGATION WITH SALINIZED WATER AND SPRAYING OF SALICYLIC ACID ON GROWTH AND FLOWERING OF Calendula officinalis

Abstract

This study was carried out to investigate the effect of saline water irrigation and foliar sprayings of Salicylic acid (SA) on growth, flowering and chemical composition of pot marigold plants in the two successive seasons of 2014/2015 and 2015/2016. Pot experiments were carried out during the two successive seasons of 2014/2015 and 2015/2016. Trials took place in the ornamental farm of the Horticulture Department, Faculty of Agriculture, Ain Shams University, Shoubra El-kheima, Qalyubia Governorate, Egypt. Local seeds of Pot marigold (Calendula officinalis L.) were sown in the nursery on October 1St. in both growing seasons, respectively. The seedlings were transplanted in the pots after 45 days from sowing. The seedlings were planted individually in black plastic pots 20 cm in diameter filled with sand medium Five concentrations of saline water irrigation were used (2000, 4000, 6000, 8000 and 10000 ppm) in addition to tap water as control. The saline water irrigation were prepared by using a mixture of two salts (sodium chloride: calcium chloride, 2:1, w/w) Three concentrations of foliar sprayings of salicylic acid were used (100, 200 and 300 ppm) in addition to spraying of tap water as control. Spraying of SA was done after two weeks from transplanting and was repeated every two weeks. Foliar sprayings were applied during early morning hours using a hand-held sprayer. Treatments were arranged in a completely randomized block design with three replicates, each replicate represented by 120 pots. Vegetative characteristics were recorded, i.e., plant height, number of leaves/plant, leaf area, number of branches/plant, diameter of stem, fresh and dry weights of vegetative growth and roots, and ro