Effects of Electrolyzed Acidic Water Treatment on Total Viable Bacterial Counts of Radish Sprouts (Raphanus sativus L.) during Cultivation

Abstract

　The total viable bacterial counts (TVBC) of radish sprouts (Raphanus sativus L.) during cultivation were constant through cultivation, and were in the order root≧seminal leaf>hypocotyl. With foliar spray treatment of electrolyzed acidic water (EAW), an antiseptic effect became more pronounced as frequency of spraying increased. The TVBC of hypocotyl and seminal leaf of radish sprouts decreased at most 1 logCFU/g compared with the control. When EAW was used as a culture of radish sprouts during cultivation or seed disinfection at 20℃, the roots of radish sprouts did not elongate and decayed. The decay of plants was not observed in seed disinfection of EAW at 2℃. However, the longer seeds were dipped in EAW at 2℃, the lower the normal germination rate became. The normal germination rate was high compared with the control when EAW treatment time was less than one hour. In the case where seed disinfection treatment with EAW was performed for a short time at 2℃, the TVBC of cotyledon of radish sprouts decreased slightly. The TVBC of hypocotyl and seminal leaf of radish sprouts decreased approximately 1 logCFU/g compared with the control. The EAW treatment at 0℃ was more effective than that at 2℃ in microbiological control. The apparent condition of radish sprouts treated with EAW was not significantly different from that of the control. The combination of seed disinfection and foliar spray treatment of EAW reduced bacterial counts compared with the control and distilled water treatment, but there was no synergism of both treatments.