Seed Halopriming Enhances Germination Performance and Seedling Vigor of Gerbera jamesonii and Zinnia elegans.

A study was conducted to investigate the effects of seed priming (halopriming with 25 mM, 50 mM and 100 mM of calcium chloride (CaCl2), potassium nitrate (KNO3), potassium chloride (KCl) and Hydropriming) on germination and seedling vigor of Gerbera jamesonii and Zinnia elegans. Seeds of Gerbera jamesonii and Zinnia elegans were primed in salt solutions and distilled water for 24 h and 12 h, respectively, and germinated at 25 ± 1 °C with 40-60% R.H. in 16/8 hours day/night conditions. Results revealed that pre-sowing seed treatment particularly halopriming with CaCl2 was the most effective for invigoration of gerbera and zinnia seeds. For Gerbera jamesonii, 25 mM CaCl2 and for Zinnia elegans, 50 mM CaCl2 proved best priming treatments followed by 100 mM KCl and 50 to 100 mM KNO3 for both tested species. This was interpreted by reduced time to 50% germination (1.2 d for gerbera and 2.4 d for zinnia), higher final germination %age (11% for gerbera and 7% for zinnia), seedling vigor (83% for gerbera and 46% for zinnia), and fresh weight (0.95 g for gerbera and 2.29 g for zinnia) and dry weight (0.3 g for gerbera and 0.5 g for zinnia) of the seedlings. These halopriming treatments (25 to 50 mM CaCl2 or 50 to 100 mM KCl and KNO3) can be commercially used by the growers for early, uniform and healthy nursery stand of the tested species, which can ensure uniform maturity and flower harvesting of ornamentals. [ABSTRACT FROM AUTHOR]