Location: Dale Bumpers National Rice Research Center
Title: A user-friendly rice seed disinfection by ultraviolet light irradiation in a biosafe flow cabinetAuthor
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 1/11/2023 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Rice is a staple food for most of the world’s population and is a model for plant research. Rice seeds have been exchanged for food, genetic studies, and breeding worldwide. Like other plant species, rice plants host many microbes from the environment. Some microbes remain in or on rice seeds, and some microbes are seed-transmissible pathogens, with serious consequences for stable rice production. For example, seed-transmissible bacteria Pantoea ananatis, Pantoea agglomerans, Sphingomonas spp., and Burkholderia glumae have been reported to cause rice blight diseases in several countries. A user-friendly method of seed disinfection can benefit global seed exchange. UV irradiation between 200 and 280 nanometer (nm) can cause critical damage to microbes. In the present study, rice seeds were irradiated by 274 nanometer germicidal ultraviolet proton in a biosafe flow cabinet. Seeds without any barrier, in a sterilized mesh bag, or in a sterilized coin envelope were removed each day for seven days after UV irradiation and then were placed in nutrient agar media in a dark incubator at 29°C for three days, after which the number of seeds contaminated with bacteria and/or fungi were counted. At the same time, seeds were removed and kept in a dark incubator at 40 °C for five days for determining the germination rate. The bacterial and fungal infection rates declined significantly over time. The germination rate did not change significantly over time. There was no significant difference among treatments for germination rate or fungal infection rate. Interestingly, the UV irradiation of seeds in mesh bags had the strongest effect on reducing bacterial infection rate over time, whereas the direct UV irradiation had a weaker effect on bacterial infection rate than the UV irradiation of seeds in mesh bags. We suggest that UV irradiation of seeds in mesh bags be used to reduce seed bacterial contamination. |