Abstract

ARAOZ, S. D.  and  DEL LONGO, O. T.. Pregerminative treatments to break the physical dormancy imposed for the endocarps in Ziziphus mistol Grisebach. Quebracho (Santiago del Estero) [online]. 2006, n.13, pp.56-65. ISSN 0328-0543.

The mistol (Ziziphus mistol Grisebach) is a native arboreal specie of Argentina with numerous uses such as feeding, tinctorial, wood, medicinal and melíferous. The fruit of mistol is a drupe that contains a woody endocarp to make difficult the germination of the seeds. The objective of this research was to select the pregerminative treatments to overcome the physical dormancy imposed for the endocarp. The endocarps were treated with physical (complete removal and abrasion of the basal zone), acid and moist scarification. Germination tests were performed top of paper (seeds) and sand or between paper (endocarps) at temperature of 25 ºC constant and photoperiod of 16/ 8 h (dark/ ligth). The results showed that complete removal of endocarps, scarification of the basal zone as scarification with concentrated sulphuric acid during 6-8 hours, are suitable methods in order to break such dormancy, improving both percentage and speed of germination. In contrast, moist scarification was ineffective for to promove germination.

Keywords : Ziziphus mistol Grisebach; Endocarp; Physical dormancy; Scarification.