Germination of seed of oil palm (Elaeis guineensis Jacq.) as affected by different mechanical scarification methods

Scarification is needed to liberate the seeds from physical dormancy. The different scarification methods, such as removal of the operculum through the germ pore, drilling two holes through the shell and removal of the shell combining with or without heat were observed to find out the best dormancy breaking method comparing with commercial dry heat (control) in tenera oil palm seed of cross 23 and 37. Among the scarification methods, operculum removal without heat gave the highest germination and showed no significant variation with control (80.66% vs 85.17%), whereas highly significant differences with all other methods which yielded very low. Time to emergence, T₅₀ and time to final germination were rapid in the operculum-removed seed without heat over the controlled seed. There were no differences of final germination in both crosses. The results suggested that operculum removal without heat affected obviously on germination. This method could remove the limitations of the control treatment associated with time consuming and high cost of process, and may be developed as a practical guide for the planters with economic aspect.