Ozone Processing of Corn Grains: Effect on Seed Vigor and Surface Disinfection

Ozone treatment of corn seeds with respect to determination on changes in germination ability, germination under salt stress, seedling growth, seedling root length, conductivity and inactivation of endogenous microflora was studied. Corn seeds immersed in water treated by fixed ozone dose of 12.5 g/m3 for 1 (1O3), 3 (2O3) and 5 min (3O3) at room temperature. Ozone treatment provided full germination (100%) of the corn seeds on the 2nd day; whereas 66.6% of the control seeds germinated on the 8th days after planting. Ozone treated seedling were significantly taller and stronger than the control samples with significantly longer seedling root. Germination under 100 mM salt stress for ozone treated seeds was significantly higher than that of the control samples. Electrical conductivity of the seeds was significantly affected by the measurement time rather than ozone treatments. Ozone treatments provided significant inactivation on total aerobic mesophilic bacteria and total mold and yeast of the endogenous bacteria revealing maximum of 5.31 and 6.15 log reductions, respectively. It was concluded that ozone treatment at 12.5 g/m3 for 5 min can be utilized to treat corn seeds as these treatment parameters provided maximum inactivation on endogenous microflora with improvement of vigor and stronger seedling formation.