seedling-growth
Seedling growth refers to the early developmental stage in which a germinated seed establishes its root and shoot systems, transitioning from stored seed reserves to independent photosynthetic life. This stage is critical for plant science because it determines a plant's establishment success, vigor, and resilience to environmental stressors like drought, temperature, and soil conditions. Studying seedling growth helps researchers understand key developmental processes, optimize agricultural yields, and predict how plant populations respond to changing environments.
open_in_new WikipediaPubMed · 2026-07-10
A gas molecule plants produce called nitric oxide acts as a brake on growth by interfering with brassinosteroids, the hormones that tell plants to grow bigger. Plants with too little nitric oxide grow faster and respond more strongly to growth hormones, while plants with too much show developmental problems.
Seedlings lacking nitric oxide show enhanced growth and hyper-respond to brassinosteroid treatments compared to normal plants.
Plants with activated brassinosteroid signaling accumulate excess nitric oxide, suggesting a negative feedback loop between the hormone and the gas.
Nitric oxide-deficient plants had elevated levels of brassinolide, the most biologically active brassinosteroid, which likely explains their faster growth.