Question

By which of the following method or methods seed dormancy can be broken or its duration can be reduced?

• A. Scratching of seed coat
• B. Layering of seeds
• C. Change in the light, pressure and temperature
• D. All of the above

Answer 1

The correct option is D All of the above

Artificial methods for breaking the seed dormancy includes scarification, low temperature, alternating temperature, running water treatment, light, and hormone treatment.

Scarification - It is the weakening of seed coats by mechanical abrasion or chemical treatments. Mechanically, the abrasions are caused by machine threshing, vigorous shaking. Chemically, the seeds are treated with chemicals like potassium nitrate, thiourea, ethylene, chlorohydrine to make the seed coats soft and weak.

Seed layering is an important technique to reduce the seed dormancy.

Low temperature (chilling) - In many woody and in certain herbaceous species the dormancy can be broken by chilling treatments, just above freezing (0 - 5${}^o$C).

Alternating temperatures - Seeds are exposed to alternating high and low temperatures to reduce the concentration of the inhibitory substances.

Running water treatment - Running water washes off the inhibitors from the seeds and breaks dormancy.

Light - In some plants, dormancy can be broken by exposing them to light.

So, the correct answer is option D.