Light is a positive regulator of strigolactone levels in tomato roots.

Strigolactones (SLs) or closely related molecules were recently identified as phytohormones, acting as long-distance branching factors that suppress growth of pre-formed axillary buds in the shoot. The SL signaling pathways and light appear to be connected, as SLs were shown to induce light-regulated pathways and to mimic light-adapted plant growth. However, it is not yet clear how light affects SL levels.