The Effects of Salt Stress in Zinnia (Zinnia sp.) Cultivars During Seed Germination and at the Early Stages of Seedling Growth

Abstract

The Zinnia genus which belongs to the Asteraceae family is an annual, multipurpose ornamental plant. Zinnia plants are cultivated not only in landscape but also as the potted plant and cut flower. One of the most important problems in the world is salinity in soil and water. The aim of this study was to determine the effects of salinity on twenty Zinnia cultivars during seed germination and early seedling growth. The salt was applied by irrigating seeds with 0 and 100 mM salt solutions. Radicle emergence, seed germination, root, hypocotyl and cotyledon lengths, relative growth index of the root, and seedling fresh weight were evaluated. At the end of the study, the radicle emergence reduction was the highest value in Zinnita Rose (52%). The highest reduction rates on seed germination were at Swizzle Cherry-Ivory, Double Zahara Raspberry Ripple (48%), and Double Zahara Yellow (48%). Root lengths of all Zinnia cultivars were dramatically decreased by salt stress. According to weighted ranked evaluation, Dreamland Ivory and Dreamland Coral were more tolerant to salt stress than other Zinnia cultivars. However, in general Zinnia cultivars were relatively sensitive to salt stress at the germination stage.