SEED SCIENCE AND TECHNOLOGY, vol.33, no.3, pp.571-579, 2005 (SCI-Expanded)
Freshly harvested Amaranthus cruentus L. seeds were primed using three different priming agents including KNO3, KH2PO4 and polyethylene glycol (PEG 8000) at various concentrations for seven days at 20 degrees C. Germination of A. cruentus seeds at 20 degrees C was promoted by priming in KNO3 but not in KH2PO4 or PEG solutions. The highest final germination percentage (FGP) was obtained from 3% KNO3 (37%) while untreated seeds had an FGP of 10%. Inclusion of methyl jasmonate (MeJA), 1-aminocyclopropane-1- carboxylic acid (ACC) or 6-benzylamino-purine (BAP) into priming solution further improved germination. Seed germination was significantly increased with all concentrations of plant growth regulators (PGR) tested, except with the highest concentrations of MeJA and ACC compared to seeds primed in KNO3 only. Three mu M MeJA included into the priming solution gave the highest final seedling emergence (FEP) with 37%. The fastest emergence rates were obtained from seeds primed in the presence of 3 mu M and 10 mu M MeJA (E-50=4.35 days). These results indicate that 3% KNO3 supplemented with 3 mu M MeJA could promote germination and emergence of dormant Amaranthus cruentus L. seeds.