Duration between the development of two consecutive leaves is\tPlastochron\tPhytochrome\tPhytotron\tAngular divergence

Plastochron - the time interval between initiation of successive primordia-leaf, flower, floral organ (wild-type Arabidosis plant will produce one leaf about every one to three days, so the leaf plastochron is about 1-3 days).

Phytochrome is a photoreceptor, a pigment that plants use to detect light. It is sensitive to light in the red and far-red region of the visible spectrum. Many flowering plants use it to regulate the time of flowering based on the length of day and night (photoperiodism) and to set circadian rhythms.

A phytotron is an enclosed research greenhouse used for studying interactions between plants and the environment.

So, the answer is Plastochron i.e. 1.