Photoperiod – is the length of time a plant is exposed to light during a 24-hour period, it plays important role while calculating DLI. (Expressed in mol/m2/day)

Photoperiod, also called light duration and day length (or day length).

Photoperiodsm is the response of plants to the length of dark and night period. In plant Photoperiodsm induces flowering.

Short Day Plants (SDPs)- These plants flowers only in short days.

Long Day Plants ( LDPs) – These plants flowers only in long days.