Stability of seed microbiota under differing durations and conditions of storage

This study applied 16S rDNA amplicon sequencing to evaluate the effects of seed storage on the taxonomic composition of the bacterial seed-endophytic microbiota. The study comprised of two main parts. In Study I, comparisons were made of the microbiota composition of oat seed (Avena sativa cv Mascani) harvested in different years, but otherwise the same in genotype and location of cultivation and stored since harvest under low-temperature and low-humidity conditions. Seed stored for 1, 8, 15 and 22 years were included in the study. The aim of the study was to determine whether the composition and diversity of the seed microbiota was dependent on the duration of storage, including whether certain taxa were more susceptible to being lost under long-term storage than others.In Study II, oat and perennial ryegrass (Lolium perenne) seed was stored for one year under differing storage conditions. Seed was stored either in the low-temperature and low-humidity conditions of a seed bank, or the variable ambient conditions within a laboratory. Within each environment, seed was stored within hermetic or non-hermetic containers. The aims of the study were to test whether seed microbiota diversity and composition were influenced by the storage environment and the type of storage container used, and whether certain taxa were more sensitive to the conditions of storage than others.