1 research outputs found
PetuniaâĂâhybrida floral scent production is negatively affected by highâtemperature growth conditions
Increasing temperatures due to changing global climate are interfering with plantâpollinator mutualism, an interaction facilitated mainly by floral colour and scent. Gas chromatographyâmass spectroscopy analyses revealed that increasing ambient temperature leads to a decrease in phenylpropanoidâbased floral scent production in two PetuniaâĂâhybrida varieties, P720 and Blue Spark, acclimated at 22/16 or 28/22â°C (day/night). This decrease could be attributed to downâregulation of scentârelated structural gene expression from both phenylpropanoid and shikimate pathways, and upâregulation of a negative regulator of scent production, emission of benzenoids V (EOBV). To test whether the negative effect of increased temperature on scent production can be reduced in flowers with enhanced metabolic flow in the phenylpropanoid pathway, we analysed floral volatile production by transgenic âBlue Sparkâ plants overexpressing CaMV 35Sâdriven Arabidopsis thaliana production of anthocyanin pigments 1 (PAP1) under elevated versus standard temperature conditions. Flowers of 35S:PAP1 transgenic plants produced the same or even higher levels of volatiles when exposed to a longâterm highâtemperature regime. This phenotype was also evident when analysing relevant gene expression as inferred from sequencing the transcriptome of 35S:PAP1 transgenic flowers under the two temperature regimes. Thus, upâregulation of transcription might negate the adverse effects of temperature on scent production.We demonstrate that petunia flowers produce less volatile phenylpropanoid compounds, in both scent bouquets and internal pools, in response to elevated temperatures. We reveal that the decrease in floral scent is correlated with reduced transcript levels of scentârelated genes, and that the adverse effect of high temperature can be negated by expressing transcriptional upâregulators. We believe that the conclusions and implications drawn from the original data presented in our manuscript will be of particular interest to a broad spectrum of your readers, particularly in view of recent changes in global climate and the risk of environmental disruption of plantâpollinator mutualism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112003/1/pce12486-sup-0001-si.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/112003/2/pce12486.pd