Plant Volatile Chemistry

A plants volatile organic compound (VOC) composition is the hand that swats unwanted visitors, welcomes visitation from much needed pollinators, and the substantial determinant in a plants identity and overall evolutionary fitness within the plant community. Understanding the mechanics of volatile formation is essential in interpreting their importance in plant life, and in plant-animal interactions. A huge allocation of energy is assumed to be given to the production of volatiles, and is therefore deemed costly to the plants, yet this allocation has seldom been quantified (Grison-Pige et al 2001). Volatile release rates that could be found for flowers (mostly Ophrys flowers) ranged from 0.001-0.008 micrograms/hour and this represented between 0.001%-1% of total energy committed to reproduction (Grison-Pige et al 2001). It is the integration of visual cues; beautiful elaborate petals, rich colors, and enchanting aromas (olfactory cues) that give each individual plant, and each species a unique set of assets to woo the otherwise non-specific group of pollinators known as generalist pollinators. It is this same association that drives the increased evolutionary fitness of plants containing both visual and olfactory cues as well as bountiful nectar rewards. In this essay I will outline. The purpose of this essay is to outline the biosynthetic pathways important in producing plant VOC’s, focusing mainly on those producing terpenes, and outlining the applications of volatile research in determining its relationship to sexual evolution within gender dimorphic plant population of Interior British Columbia.
Production Center of Volatile Organic Compounds:
VOC’s are produced within the organelles of the plant cell (Pichersky 2006) (Figure 1). The plastid produces such precursors to the volatiles as methylketones, aldehydes, sesquiterpenes, diterpenes, carotenoids, phenylpropenoids and benzenoids (Pichersky 2006). These pre-cursors can then be oxidized, reduced,

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