Light Strengthens Plant Tissues While Limiting Stem Growth, Study Finds

Tue, 14 Apr 2026 10:41:00 +0200

Researchers at Osaka Metropolitan University have discovered a previously unrecognized mechanism by which light influences plant growth. Focusing on young pea stems, the team found that plants grown under light conditions show significantly stronger adhesion between the outer epidermal layer and the inner tissues compared to those grown in darkness. This stronger connection is linked to increased levels of a compound called p-coumaric acid, a phenolic substance known to reinforce plant cell walls. Using fluorescence microscopy and tissue adhesion measurements, scientists confirmed that light exposure boosts the accumulation of this compound, effectively strengthening the structural “glue” that binds plant tissues together.

While this reinforcement improves structural stability, it also creates a biological trade-off. The tighter bonding between tissues restricts the ability of inner cells to expand, thereby limiting overall stem growth. In other words, light not only supports plant de