This curiosity of many glasshouses has beautiful green flowers that emit a less than beautiful smell. For large parts of the year, this evergreen shrub would go unnoticed but in the spring it is a different story. Native to Mexico, the plant is in the Theophrastaceae family which has been subsumed into the wider primula family as part of the Angiosperm Phylogeny Group III update. The Theophrastaceae was named after Theophrastus (Greek, 1st century BC), who is often known as the 'father of botany' for his writings on plants.
The startling green flowers (smaragdina means emerald green) look almost unreal. They have anthers that sit very close to the central stigma as the flower opens but then the anthers later spring away revealing the stigma.
The revolting smell that the flowers emit is a characteristic of sapromyophily - or pollination by flies that normally visit dead animals or dung! Charming….
A study of floral odours of plants in the Theophrastaceae reveals that the horrid smell is due to 3-methylbutanoic acid - a minor component of the essential oil but the one that has the overriding impact on the smell nonetheless. This acid (also known as isovaleric acid) is reported to have a 'strong pungent or cheesy smell' and is indeed the major component of the cause of unpleasant foot odour when it is produced by skin bacteria metabolising leucine!
3-methylbutanoic acid or isovaleric acid
Alison Foster
Oxford Botanic Garden
Data: 04.03.2013
Nenhum comentário:
Postar um comentário