Abstract

Tropical rain forests contain an ecologically and physiologically diverse range of vegetation and habitats. Sun-acclimated plants can be divided into two groups, shade-tolerant and shade-intolerant, according to the plant’s physiological and genetic responses. Some tropical species have potential capacity for light damage in a shaded environment as well as shade-tolerance to compensate for the impaired light harvesting complex. In particular, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is regulated by the Calvin cycle, which participated in protein synthesis.Rubisco plays a role in CO₂ fixation, which helps supply the energy to regulate Rubisco for ribulose 1,5-bisphosphate (RuBP) reduction. Light intensity is associated with the photosynthetic rate and genetic response to moderate growth environments.

Key words: Gene expression, growth, light intensity, Rubisco activity.