Practices to enhance germination seed sizing (larger seeds have shown greater viability and vigor) seed priming pregerminated seeds

Principles of seed priming use of osmotic or matric forces to hold seeds in the lag stage before redrying controls seed hydration to permit pregermination metabolism but prevent radicle emergence results in more uniform germination in a shorter time span

Seed priming - two methods osmotic seed priming seeds are placed in an aerated soln of PEG for 1-15 days seeds are dried (to near original weight) matrix seed priming PEG soln is replaced with a solid matrix (e.g., vermiculite) “matrix force” is created by limiting moisture used commercially for lettuce and pansy to overcome thermodormancy

Pregermination germinated seeds are dispersed in a gel (fluid drilling) or dried before use advantages: fast, uniform germination at or near 100% disadvantages: increased cost, seeds with a shorter shelf life