GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE320nnn/GSE320194/primary200OKTranscriptomicsAvena sativaExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE320194GEOGSEfalseEar Photosynthesis Outweighs Flag and Top Second Leaf Contributions to Oat Grain Weight and Oil AccumulationOat endosperm uniquely accumulates oils, differing from other Poaceae crops and oilseed species that primarily store oils in embryos. Different photosynthetic organs' contribution to grain oil accumulation remains unclear. This study investigated the effects of photosynthesis on grain weight and oil accumulation in the ear, flag leaf, and top second leaf of four oat cultivars with varying oil contents, using shading/excision treatments. Studies have shown that ear shading significantly affects grain weight and lipid accumulation in oats. These effects were more pronounced in high-oil cultivars than low-oil cultivars. We further performed transcriptome profiling on the high-oil oat cultivar BY9 at 4 days after ear shading. Transcriptomic analysis indicated that shading altered expression patterns of genes associated with carbohydrate metabolism, fatty acid synthesis, and triacylglycerol assembly. Our findings highlight the critical role of ear photosynthesis in determining both oil production and yield in oats, providing new insights into oil accumulation mechanisms in cereal crops.2026/06/30GSE320194GSM9537112GSM9537111GSM9537113GSM9537110GSM9537109GSM953710836638320194Avena sativa