fytokromin
Fytokromin is a term that appears to be a misspelling or a non-standard term. It is highly probable that the intended subject is either phytochrome or a chemical compound derived from plants, often referred to as a phytotoxin or phytochemical.
Phytochrome is a photoreceptor protein that plays a crucial role in plant development and responses to light.
If "fytokromin" refers to a plant-derived chemical, it could be a phytotoxin, which is a toxic compound