Blue light made the levels of a key growth hormone (GA3) drop by about 14% in tall soybeans and 20% in short soybeans when grown in the dark versus under blue light.

Blue light raised the stress hormone jasmonic acid by about 15% in tall soybeans and 38% in short soybeans compared to plants grown in the dark.

When soybean plants were exposed to blue light, their height dropped by about two-thirds compared to plants grown in the dark, with both tall and short varieties showing similar reductions.

Under blue light, the stress hormone salicylic acid increased by about 56% in tall soybeans and 41% in short soybeans compared to plants grown in the dark.

Blue light made a key salicylic acid protein (NPR1) increase by 40% and a gibberellin receptor protein (GID1) decrease by 18% in soybean stems.

In short soybeans, adding brassinolide hormone made stems grow longer under blue light but shorter in the dark, showing light-dependent effects of this hormone.