P-409 - Evaluation of Sorghum-based Fusarium and Pythium Inoculum for Survival and Efficacy Under Storage and Soybean Field Conditions

Field trials in plant protection research often involve artificial inoculation with pathogens to evaluate the response of various treatments. The efficacy of disease inoculum depends on both pathogen viability and load. This study investigates the viability and inoculum load of Fusarium virguliforme, F. graminearum, and Pythium spp. in sorghum seed-based inoculum under storage and field conditions. Inoculated sorghum seeds will be sampled at four stages: (1) before drying, (2) after drying, (3) after 30 days of storage, and (4) 30 days after planting. A total of 10 inoculum seeds per pathogen will be sampled at each stage, serially diluted, and plated on selective media with four replicates. Colony-forming units (CFUs) will be recorded to quantify pathogen survival and load. Disease severity in field plots will be assessed, and regression analyses will be used to determine the relationship between CFUs and disease development. This study aims to examine inoculum viability during preparation, storage, and application, contributing to improved management of soybean disease trials.