What is "phyllochron"

The phyllochron is the intervening period between the sequential emergence of leaves on the main stem of a plant, also rendered as leaf appearance. This measurement is used by botanists and agronomists to describe the growth and development of plants, especially cereals. The term phyllochron was first described in 1966. The interval between leaf appearances can be recorded in both standard measurements of time as well as thermal time (e.g. growing degree units). One phytomer unit is added over the course of one phyllochron. No significantly robust equation to predict phyllochrons has been developed.