Caseiro et al. (2004) found that hydropriming was the most effective method for improving seed
germination of onion, especially when the seeds were hydrated for 96 h compared to 48 h. When seeds
imbibe, the water content reaches a plateau and changes little until radicle emergence (Bradford, 1986).
Priming up to this point can have a positive effect, while extended priming duration may negatively affect
germination. In other words, Duration of seed priming, especially hydropriming, affects seed germination
properties. Longer hydropriming duration has not always more positive effect on seeds germination
properties. Ghassemi-Golezani (2010b) reported that the lowest mean germination time and the highest
germination percentage and seedling dry weight of pinto bean were achieved with 7 and 14 hours priming
duration which was significantly different from 21 hours of hydropriming.