A comparison of pretreatment methods for scarification and germination of Tamarindus indica L. seeds

Seeds of tamarind (Tamarindus indica L.) were germinated following seven pr etreatments, viz., control, mechanical scarification by scratching the regi on near the hilum on coarse sand paper or nicking it with a knife and acid scarification by immersion in concentrated sulphuric acid (H2SO4) for 15, 3 0, 45 and 60 minutes. Final emergence was 100% for all pretreatments, but d ays to first emergence (E-ist), days to 50% emergence (E-50) and mean emerg ence time (MET) varied significantly among them. The best germination respo nse occurred with acid pretreatment followed by mechanical scarification. E -ist, E-50 and MET decreased as acid pretreatment time increased. Scratchin g on a coarse sand paper advanced the E-50 by 4.5 days and shortened the ME T by 4.1 days compared to nicking.