Abstract

Seeds of Isabgol (Plantago ovata Forsk) were divided into three sub-samples, one of which was kept as control (unprimed), a sub-sample was soaked in 0.8% NaCl solution and another sub-sample was pretreated with 0.8% KNO₃ solution for 4 h in an incubator adjusted to 15°C. In laboratory, the highest germination rate and seedling dry weight were obtained by seeds primed with KNO₃. In the greenhouse, means of plant biomass, grain and mucilage yields per plant decreased with increasing salinity. The highest grain andmucilage yields were produced by the plants from seeds primed with KNO₃, which were not significantly different from those primed with NaCl. Neither salinity nor salt-priming had significant effect on turgidity coefficient and mucilage percentage. No significant interaction of salinity × salt-priming on Isabgol performance suggested that salt-priming can improve grain and mucilage yields of this medicinal plant under both saline and non-saline conditions. Therefore, salt-priming can be used to promote seed germination rate, seedling dry weight and grain yield of Isabgol which ultimately can enhance mucilage production.

Key words: Germination rate, Isabgol, mucilage yield, salt-priming, seedling dry weight.