Ultrasonic Priming and Sprouting

• An ultrasonic treatment of seeds is a useful pre-sowing technique to stimulate germination.
• Sonication is an efficient technique for breaking seed dormancy and improving the germination characteristics.
• Hielscher ultrasonic equipment can be precisely controlled for reliable outcome of seed germination and priming.

Ultrasonic Germination

A rapid germination and seedling emergence are critical factors for a successful establishment of plants and crops. Dormancy breaking and germination stimulation are important for proliferation and early production of plant seedlings. Ultrasonication of seeds in water oder an osmoticum improve the germination rate and speed and show a higher germination percentage than untreated seeds. Mild sonication stimulates the vegetal cells

Ultrasonically induced shell fragmentation, perforation and enlargement of the pore size of seeds lead to a higher water retention capacity in seeds and grains resulting in improved hydration. Ultrasonic endosperm modification, such as starch degradation by sonication, increases the rate of enzyme-catalyzed hydrolysis reactions within the seeds. An increased enzyme activity and hydrolysis accelerates germination and embryo growth as result of the ultrasonic treatment.

Sonicated lentils (40Ws/g w/ UP200St) in comparison with non-sonicated lentils: The sonicated lentils show a higher gemination rate and longer shoots.

Scanning electron microscopy (SEM) pictures of Arabidopsis seeds.
a–c Seed subjected to sonication at 24°C for 30sec.
d, e dry seed, f, g seed placed in water for 4 days at 4°C,
h, i, germinated seeds. Source: Lopez-Ribera et al. 2017

Ultrasonic Priming

Priming of seeds in osmotica such as mannitol, polyethylene glycol (osmopriming), saline solutions (e.g., CaCl₂, NaCl or CaSO₄) (halopriming) and in water (hydropriming) can be easily improved by the application of ultrasound waves. Sonication improves the mass transfer between the seed and the surrounding solution resulting in an increased uptake of solution (i.e. water, nutrients etc.) into the seed is achieved. Ultrasonically assisted priming is an economical, simple and a safe technique for increasing the capacity of seeds to osmotic adjustment and enhancing seed germination, seedling establishment and crop production under stressed conditions.
Read more about ultrasonic priming here!

Ultrasonic Processors for Germination and Priming

To improve germination of seed by sonication, precisely controllable and adjustable ultrasonic systems are required. Since the ultrasound waves are used stimulate physiological activities of vegetal cells, the intensity of sonication must be adapted to the specific type of seed and cultivar. Hielscher ultrasonic systems can be set to mild amplitudes delivering the cavitation and/or oscillation required to prime seeds for optimal germination and vigour. Seed treatment can be applied in batch as well as in continuous flow mode. The broad spectrum of accessories allow for the easy integration of ultrasound into existing premises.
Hielscher’s ultrasonic systems increase the potential for high seedling performance after sowing.
The table below gives you an indication of the approximate processing capacity of our ultrasonicators: