title: Physiological, biochemical and molecular responses of the potato (Solanum tuberosum L.) plant to moderately elevated temperature.
abstract: Although significant work has been undertaken regarding the response of model and crop plants to heat shock during the acclimatory phase, few studies have examined the steady-state response to the mild heat stress encountered in temperate agriculture. In the present work, we therefore exposed tuberizing potato plants to mildly elevated temperatures (30/20 °C, day/night) for up to 5 weeks and compared tuber yield, physiological and biochemical responses, and leaf and tuber metabolomes and transcriptomes with plants grown under optimal conditions (22/16 °C). Growth at elevated temperature reduced tuber yield despite an increase in net foliar photosynthesis. This was associated with major shifts in leaf and tuber metabolite profiles, a significant decrease in leaf glutathione redox state and decreased starch synthesis in tubers. Furthermore, growth at elevated temperature had a profound impact on leaf and tuber transcript expression with large numbers of transcripts displaying a rhythmic oscillation at the higher growth temperature. RT-PCR revealed perturbation in the expression of circadian clock transcripts including StSP6A, previously identified as a tuberization signal. Our data indicate that potato plants grown at moderately elevated temperatures do not exhibit classic symptoms of abiotic stress but that tuber development responds via a diversity of biochemical and molecular signals.
authors.affiliation: Cellular and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Hancock
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Morris
authors.forename: Laurence J M
authors.initials: LJ
authors.lastname: Ducreux
authors.forename: Jenny A
authors.initials: JA
authors.lastname: Morris
authors.forename: Muhammad
authors.initials: M
authors.lastname: Usman
authors.forename: Susan R
authors.initials: SR
authors.lastname: Verrall
authors.forename: John
authors.initials: J
authors.lastname: Fuller
authors.forename: Craig G
authors.initials: CG
authors.lastname: Simpson
authors.forename: Runxuan
authors.initials: R
authors.lastname: Zhang
authors.forename: Pete E
authors.initials: PE
authors.lastname: Hedley
authors.forename: Mark A
authors.initials: MA
authors.lastname: Taylor
mesh_terms: D017398:Alternative Splicing; D002244:Carbon / Q000378:metabolism; D056925:Circadian Rhythm Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018869:Heat-Shock Response; D055442:Metabolome; D010084:Oxidation-Reduction; D010788:Photosynthesis; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011198:Solanum tuberosum / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D013696:Temperature
chemical_list: D056925:Circadian Rhythm Signaling Peptides and Proteins; D010940:Plant Proteins; D002244:Carbon
keywords: development; heat; metabolome; oxidative stress; secondary metabolism; transcriptome; tuberization