http://www.actahort.org/books/362/362_23.htm

ISHS Acta Horticulturae 362: International Symposium on Agrotechnics and Storage of Vegetable and Ornamental Seeds
Effect of Thermic Treatments and Seed Manipulation on Emergence of Dwarf Pomegranate (Punica granatum L. 'Nana').
C. Cervelli

Abstract: Three trials were carried out to increase emergence rate and contemporaneity of seeds of dwarf pomegranate (Punica granatum 'nana'). Trials concerned seed manipulation and thermic treatments on seeds (with or without fleshy coat) before sowing. Removal of fleshy coat only gave similar results to intact seeds. Better results were obtained washing the seeds (48 hrs) after pulp removal or removing pulp three months before sowing (on seed harvest). Stratification at 3°C/30 days of intact seeds (with fleshy coat) increased both emergence rate and contemporaneity compared to no-stratified or to 15°C/30 days stratified seeds. With seeds free of fleshy coat a 15°C stratification increased emergence rate compared to no-stratified or to 3°C stratified seeds. In the case of seeds free of fleshy coat an increase of stratification time from 30 to 60 or 90 days was uneffective. The hypothesis of the existence of a germination inhibitor, water soluble and inactivated at low temperature, inside the fleshy coat of the seed is suggested.