Various environments exist worldwide, from high-latitude regions with long winters to tropical regions with warm temperatures year-round. The seasonal activities (phenology) of plants inhabiting each region affect the global environment. However, the genetic control that governs phenology and its responsiveness to climate and environment remains unclear. Therefore, we will perform genome sequencing of the dominant tree species in forest ecosystems. We will conduct comprehensive gene expression (molecular phenology) and phenology observations, such as BVOC emissions in diverse forest ecosystems from Hokkaido to Southeast Asian tropical forests. We will elucidate the mechanisms of phenological changes at the gene level. In addition, we will apply information on plant environmental responses obtained in a controlled laboratory environment to molecular phenology data. We will develop a phenology prediction model necessary for input into climate models by verifying predictions of leaf development, flowering, and BVOC emissions. Furthermore, the prediction results of the climate model will be fed back into the phenology prediction model. Consequently, we aim to elucidate the particulars of plant self-feedback through climate modification. Specifically, we will explore how flowering and fruiting phenology, which is sensitive to temperature and rainfall, is influenced by BVOC emissions.