Inflorescence Photosynthesis Determines Resource Allocation, Seed Production and Senescence in an Agricultural Weed.

Inflorescence photosynthesis in Avena fatua supports seed development and influences leaf senescence, with CO2 assimilation rates of 6.54 μmol m−2 s−1.

• Why it matters: Understanding how weeds optimize reproductive output despite potential trade-offs can inform management strategies and reveal fundamental plant resource allocation mechanisms.
• What they did: The study measured inflorescence CO2 assimilation, analyzed transcriptomes of floral organs versus leaves and stems, and conducted source-sink manipulations like shading and de-awning to assess effects on seed traits and senescence.
• The result: Inflorescence photosynthesis contributes to seed size and protein content, delays stem senescence, and reduces leaf photosynthesis, indicating a feedback loop that reallocates nitrogen and supports seed development in Avena fatua.