Johnson grass is one of the most serious
weeds for agricultural crops in many countries of the
world. The reason for this risk is due to its biological
properties, like reproducing by seeds and rhizomes.
Although it produces a large amount of seeds, its
germination rate is very low and supports the seed bank
in the soil. The reason for this low rate is the dormancy
imposed by the impermeable coat of the seed. In this
study, several methods of breaking dormancy of
Johnson grass seeds were tested. Diverse eight
treatments were applied: concentrated sulfuric acid,
mechanical scratch, gibberellic acid, concentrated
sulfuric acid + gibberellic acid, mechanical scratch +
gibberellic acid, 24-hour immersion in distilled water,
exposure to low temperatures (2°C) and control.
Germination ratio, mean germination time, aerial part
length, root length and seedling weight were calculated.
There were significant differences in germination
percentage between some methods. The highest
germination rate was in the treatment of sulfuric acid +
gibberellic acid (56.7%) and the lowest was in control
Keywords : Breaking Dormancy, Germination, Johnson Grass.