Rafflesia blooms with one of the largest flowers in the world. It is known for exuding a strange ammonia-like odor to entice flies, but its flower only opens for a few days and its native region is limited, which has resulted in it being known as the "phantom flower." In addition to this, as it has no leaves, stem or roots, it does not obtain nutrients itself through photosynthesis. It has the unique ecology of being completely parasitic, relying on a vine peculiar to the grape family. Due to its rarity, clarification of its ecology had not advanced.
A research team consisting of Senior Researcher Yayoi Takeuchi of the Biodiversity Division, National Institute for Environmental Studies, Japan, and his colleagues has carried out a detailed ecological survey of the Rafflesia population discovered by chance in Sarawak in Malaysia due to the development of a hydroelectric dam. The results of the survey have clarified that the plant shows extremely rapid growth during the maturation period directly before flowering, even though its youthful flower bud growth is very slow during its early life cycle. Moreover, the group estimated that around a year is needed for the plant to go from a shoot of a size that can be seen to an open flower. On the other hand, there are areas in which over 80% of flower buds wither before they flower. It is understood that Rafflesia is extremely vulnerable to natural disturbances and being trampled by humans.
In recent years, there have been rapid changes in the use of land in tropical forests, and rare plants and animals, including Rafflesia, are losing their habitat. Based on the outcomes of this survey, it is hoped that the group will be able to obtain a clear understanding of the full picture of the diverse organisms living in Sarawak, and contribute to biodiversity conservation and the establishment of forest management and protected areas.
The mature bud opens over around two days.
The full, open flower lasts for a day or two, and then rapidly decays.