Effect of stratification and seaweed extract on germination indices of two cultivars of Lisianthus (Eustoma grandiflorum L.)

This study was conducted to investigate the effect of seaweed extract, stratification, and the combined application of the best results in these two treatments on seed germination characteristics of two Lisianthus (Eustoma grandiflorum L.) cultivars (Arena and Mariachi). The first experiment consisted of seaweed extract containing 5 concentrations of 0, 250, 500, 750, and 1000 ml L-1 and stratification treatment of seeds at 4 °C (before planting) for 15, 30, and 45 days as it was applied separately to determine the best concentration and the best time. In the second experiment, the best results obtained from the first experiment included treatment of stratification (30 and 45 days of stratification) and seaweed extract (125 and 250 ml L-1) combined based on a factorial experiment in five replications on seed germination of two cultivars of Lisianthus was examined. The results showed that the percentage and speed of final germination, and the average daily germination in Arena cultivar was higher than Mariachi cultivar. With the increase of stratification days, the percentage of final germination and the average daily germination had an increasing trend. The 30-day stratification treatment  and 125 ml and 250 ml of seaweed extract resulted in the highest final germination rate and the lowest average germination time. Interaction of stratification and seaweed extract had a higher average daily germination than the control treatment. The use of seaweed extract had a positive effect on germination indices compared to the control. With the increasing concentration of seaweed extract, the need for stratification decreased.