Plant Physiology & Development
Reproductive Source–Sink Transition
As flowering progresses, expanding inflorescences and developing reproductive tissues become major sinks. The plant's allocation pattern changes alongside canopy aging, root activity, light interception, and reproductive development.
Key concepts
- Flowering changes the distribution of growth demand across the plant
- Reproductive sinks compete with continued vegetative growth and root maintenance
- Lower-canopy leaves may contribute differently depending on light exposure and tissue age
- Pollination and seed development can alter sink demand within flowers
- Late-cycle decline can reflect development, stress, disease, or combinations and should be separated with evidence
What to measure or observe
- Track flower expansion and branch growth simultaneously
- Map canopy light interception as flowers increase in size
- Record lower-leaf senescence and root-zone condition together
- Compare pollinated and unpollinated sites when relevant
- Use repeated maturity observations rather than one late-cycle snapshot
Common mistakes
- Assuming flowering stops all vegetative metabolism
- Treating every lower-leaf decline as normal fade
- Ignoring root health late in flower
- Assuming pollination affects only seed presence and not resource allocation
- Using calendar week alone to infer reproductive demand
Visuals this lesson still needs
- Vegetative-to-reproductive sink transition map
- Flowering allocation timeline
- Pollinated versus unpollinated sink comparison
- Late-cycle senescence differential