Rungsimun Thirawongphinyo
Kasetsart University, Thailand
Title: Fungal Inactivation by Ultrafine Bubble and Gaseous Ozone Technique on Rice seeds
Biography
Biography: Rungsimun Thirawongphinyo
Abstract
Rice seed-borne fungi and fungal contaminations brought to quantity and quality loss, seed transmission, germination of seedling and rice mycotoxin endanger human health and animal consumption. The potential of ultrafine bubble water (UBW) and ozone gas (OZ) to reduce seed contamination were investigated. Rice seed ‘Khao Dawk Mali 105’ (KDML105) samples were collected from farmer’s barn located in Kalasin province, Thailand for experiments. Afterward, seed-borne fungi were investigated by blotter method, determined percentage of infection on seeds and classified. The selected seed-borne fungi: Curvularia lunata and Cladosporium cladosporioides were prepared spore suspension and treated by UBW at varies sterilization period with different concentrations for inhibit spore germingaion. The treated spore suspension were diluted, spreaded on PDA agar plate and kept at 25°C for 48 h. The result showed that high concentration of UBW reduced spore germination in both species and significantly delayed fungal germination rate. The OZ treatment were applied on naturally and artificially contaminated rice seed samples at 60 and 120 ppm for 5, 10 and 20 min. However, percentage of contamination of C. lunata, Aspergillus flavus and Penicillium sp. were slightly increased. Additionally, OZ treatments did not significantly effected on seed germination in comparison to untreated.