IMPACT OF PRESSURE INFUSION OF SH-2 SWEET CORN SEED WITH PSEUDOMONAS-AUREOFACIENS ON SEEDLING EMERGENCE

Pressure infusion, a new method using increased atmospheric pressure t o inoculate seed with the biocontrol agent (BCA) Pseudomonas aureofaci ens,was evaluated for control of Pythium in shrunken-2 (sh(2)) sweet c orn seed. Pressure infusion increased seed hydration rates, especially in damaged areas. Shrunken-2 sweet corn (Zea mays L.) seed often cont ains incomplete pericarp layers and internal open spaces both within t he seed and between the aleurone layer and the pericarp. We hypothesiz ed that pressure infusion may increase the effectiveness of the BCA in oculation through delivery of bacteria to areas deep within the seed. However, pressure infusion reduced final emergence in both growth cham ber and field experiments. Rapid hydration of the pressure-infused see d may have caused tissue damage. Bio-priming of pressure-infused seed increased final emergence. The BCA reduced Pythium infection of sh(2) sweet corn seed 48 h after planting. Pressure infusion of seed did not significantly affect the incidence of Pythium infection when compared to other treatments using the BCA.