The 2011 ASHS Annual Conference

This study was to quantify the variations of 43 pepper genotypes in tolerance to salt during germination.  Seeds of 43 genotypes of peppers were germinated in five solutions: 0 (control, distilled water), 50, 100, 150, or 200 mM NaCl solutions. The actual electrical conductivities of the above solutions were 0, 5.2, 9.7, 14.0, and 18.3 dS/m.  Twenty five seeds (one experimental unit) were placed evenly on a germination paper, which was wet with treatment solutions.  The paper was folded and placed in a pre-labeled zip-lock plastic bag and placed in a temperature-controlled room (23.5 C).  There were four replications per treatment (solution). Seed was considered germinated when the primary root was 5 mm or longer. Germination was counted three times a week for two weeks in Expt. 1 and twice a week for three weeks in Expt. 2.  The treatments were the same in both experiments.  At the end of the germination experiment, the radical and hypocotyls lengths of three seeds per replication were measured. The two experiments generally had similar results for most genotypes on tolerance to NaCl salt. About 30 genotypes were moderately tolerant or tolerant to NaCl salts based on final germination percent, time to germination, and radical and hypocotyl lengths.  Six genotypes were sensitive or moderately sensitive to salt stress during germination.  Based on our previous research on salt tolerance at seedling and mature plant growth stages in the greenhouse and field conditions, peppers were more tolerant to salt during germination (radical elongation) than other growth stages. Further studies are needed to determine the salt tolerance for seedling emergence, seedling growth and reproductive growth stages.