Accelerated Germination of Pepper Seed by Priming with Salt Solutions and Water

Sweet pepper (Capsicum annuum L. cv . Keystone Resistant Giant #3) seeds were imbibed (primed) in salt solutions to determine a) what concentrations would inhibit radicle emergence and b) the influence this delay in radicle emergence would have on subsequent germination. Seeds were primed for 17 days at 23C in petri dishes with KNO 3 , KCl, NaCl, K 2 SO 4 , Na 2 SO 4 , 1 NaCl: 1 CaCl 2 (mol/mol), Ca(NO 3 ) 2 , CaCl 2 , Na 2 HPO 4 , and K 2 HPO 4 in 10, 25, 50, 100, 200, or 300 m m of the salts. Germination was not inhibited in the 10- to 100-m m salt range, although most 200- and all 300-m m solutions reduced radicle emergence to <5.0%. The time to 50% germination (T 50 ) of these primed seeds in water significantly (P < 0.01) decreased, when compared to unprimed seeds, and a negative correlation (r = – 0.98) was observed between this reduction and the osmotic potential of the solutions. Solutions with the highest osmotic potentials most severely reduced T 50 without reducing the final germination percentage. For seeds primed in K 2 SO 4 or Na 2 SO 4 (200 and 300 m m ) through 18 days, the reduction in T 50 and duration of priming were negatively correlated (r = - 0.99). Seeds soaked in double distilled water and then dried germinated faster than controls, but not as fast as seeds primed in salt solutions. Priming of pepper seeds in this study was dependent on the osmotic potential of the solution, rather than a specific salt, and the duration of treatment.