Pre – germination Seed Treatment

1. Chemical (Acid scarification):

• The purpose is to modify hard or impermeable seed covering generally soaking seed in concentrated sulphuric acid is an effective method
• The time of treatment may vary from 10 minutes to 6 hour according to species
• After treatment seeds are thoroughly washed in clean water to make them free of acid and then resown immediately. i.e. the seeds of ber, cotton, Asparagus are treated with 50% concentrated H2SO4.
• The seeds are soaked in acid for 3 to 5 minutes

2. Mechanical Scarification:

• Seeds of a few species with impermeable seed coat i.e. hard seed coat can be rendered permeable to water and gases their germination is greatly improved by mechanical scarification in taking care that seeds should be injured not be injured heavily
• This can be achieved by

1. i) Placing the seeds between two sand paper , one station and other revolving
2. ii) Passing seeds through machine that scratches the surface

iii) Notching to make the seed coat permeable to water

3. Boiled Water Treatment:

• Pouring boiling water over seeds and getting it to cool gradually for about 12 hours to soften dry and hard-shelled seeds. E.g. Coffee, Canna, etc.

• This will hasten the process of germination.

4. Soaking in Water:

• The purpose of soaking seeds in water is to modify hard seed coats, to remove inhibitors to soften seed and to reduce the time of germination
• The time of soaking seeds in cold water depend upon the hardness of the seed coat
• E.g Gulmohar, peas, beans, cassia tree etc

5. Stratification (Moist Chilling):

• Seed of many woody trees or shrubs are exposed to low temperature to bring about prompt and uniform germination
• Stratification has some benefit in softening the seed coats
• The seeds are arranged in alternate layers of sand in shallow boxes for pits or trenches.
• This condition helps in rapid germination peach cherry, plum, oat, grapes