Resumo

MARIN SANCHEZ, José et al. Osmotic conditioning of onion seeds (Allium cepa L.). Agric. Téc. Méx [online]. 2007, vol.33, n.1, pp.63-71. ISSN 0568-2517.

The osmotic conditioning of seeds, also known as osmopriming or priming is considered a promising technique to improve seed germination, resulting in a rapid and synchronous seedling emergence (invigoration). The objective of the present work was to evaluate the effect of osmopriming on the physiological quality of onion seeds after four storage periods. Seeds of onion cv. "Early Supreme" were osmoprimed with KNO₃, KCl and polyethylene glicol (PEG-8000) at -5, -10, -15 and -20 atm for 48, 72 and 96 h. Primed seeds were stored at 10 °C during 0, 7, 90 and 180 days. After each storage period a standard germination test was performed. The parameters evaluated were: percentage of germination, abnormal seedlings, dead seeds, 50% germination and seedling dry weight. Results showed higher invigoration in plantlets from untreated control treatment. In comparison with other tested treatments priming with PEG-8000 at -5 atm for 48 and 72 h improved seed physiological quality, quality that persisted all storage periods.

Palavras-chave : Germination; invigoration; priming.