Abstract

Salinity is a recurring abiotic stress in arid and semi-arid regions, which negatively affects the establishment and growth of plants, however, the cultivation of ornamental species such as celosia argentea can tolerate saline conditions. The objective of this work was to evaluate the emergence and seedling growth of Celosia argentea cultivated under different electrical conductivities of irrigation water. The experiment was carried out in a greenhouse, in the month of July 2021. The experimental design was completely randomized with five treatments and four replications. The treatments were five electrical conductivities of irrigation water (ECw), being: 0.5; 1.5; 2.5; 3.5 and 4.5 dS m^-1. They were analysed the emergence variables (percentage of emergence, average emergence time, average emergence velocity and emergence velocity index) and the growth variables (seedling height, number of leaves, stem diameter, primary root length, shoot dry weight and root dry weight) at seedling start. Moderate salinity improves seed vigor, increasing the percentage of C. argentea seedlings that emerge, culminating in satisfactory initial growth. The electrical conductivity ECw 2.5 dS m^-1 is the salinity threshold that keeps the salinity-tolerant C. argentea species above the threshold and becomes sensitive to salts.

Keywords:
floriculture; salt stress; seedling; semiarid