Initial Development of Safflower Submitted to Irrigation Water Salinity Levels

Safflower cultivation is an alternative to tropical cropping systems, with a good rusticity and some tolerance to saline stress in some cultivars. With the increase of irrigated areas around the world, salinization of the soil is an inherent concern, being the management of irrigation and cultivated species fundamental. The objective of this study was to evaluate the growth and initial development of safflower culture submitted to irrigation water salinity levels. The experiment was carried out in a greenhouse in a completely randomized design consisting of five irrigation water salinity levels (0, 2, 4, 6 and 8 dS m-1) and six replications. The saline solution was prepared using NaCl and measured with a conductivity meter. Plant height, number of leaves and stem diameter at 26 and 41 days after emergence, and shoot dry weight were evaluated; root volume; root dry mass; total dry mass and dry root/shoot mass ratio at 41 days after plant emergence. There was no visual influence of salinity levels in the evaluations at 26 days after plant emergence. However, 41 days after plant emergence, the increase in salinity levels promoted a decrease in all analyzed variables, except for root volume. Safflower does not tolerate irrigation with saline water. The damages occur from 2 dS m-1, but the largest reductions in the initial development of safflower occur from 6 to 8 dS m-1.