TY  - JOUR
AU  - Poiré, R.
AU  - Schneider, H.
AU  - Thorpe, M.R.
AU  - Kuhn, A. J.
AU  - Schurr, U.
AU  - Walter, A.
TI  - Root cooling strongly affects diel leaf growth dynamics,water and carbohydrate relations in Ricinus communis
JO  - Plant, cell & environment
VL  - 33
SN  - 0140-7791
CY  - Oxford [u.a.]
PB  - Wiley-Blackwell
M1  - PreJuSER-9495
SP  - 408 - 417
PY  - 2010
N1  - We thank Beate Uhlig for her support during the breeding of the plants. Richard Poire thanks the International Helmholtz Research School of Biophysics and Soft Matter for the stimulating discussions emerging from this interdisciplinary study, and acknowledges the support of his PhD thesis at the Heinrich-Heine-Universitat Dusseldorf.
AB  - In laboratory and greenhouse experiments with potted plants, shoots and roots are exposed to temperature regimes throughout a 24 h (diel) cycle that can differ strongly from the regime under which these plants have evolved. In the field, roots are often exposed to lower temperatures than shoots. When the root-zone temperature in Ricinus communis was decreased below a threshold value, leaf growth occurred preferentially at night and was strongly inhibited during the day. Overall, leaf expansion, shoot biomass growth, root elongation and ramification decreased rapidly, carbon fluxes from shoot to root were diminished and carbohydrate contents of both root and shoot increased. Further, transpiration rate was not affected, yet hydrostatic tensions in shoot xylem increased. When root temperature was increased again, xylem tension reduced, leaf growth recovered rapidly, carbon fluxes from shoot to root increased, and carbohydrate pools were depleted. We hypothesize that the decreased uptake of water in cool roots diminishes the growth potential of the entire plant - especially diurnally, when the growing leaf loses water via transpiration. As a consequence, leaf growth and metabolite concentrations can vary enormously, depending on root-zone temperature and its heterogeneity inside pots.
KW  - Carbohydrate Metabolism
KW  - Carbon: metabolism
KW  - Circadian Rhythm
KW  - Cold Temperature
KW  - Plant Leaves: growth & development
KW  - Plant Roots: growth & development
KW  - Plant Roots: physiology
KW  - Plant Transpiration
KW  - Ricinus: growth & development
KW  - Ricinus: metabolism
KW  - Ricinus: physiology
KW  - Water: physiology
KW  - Xylem: physiology
KW  - Carbon (NLM Chemicals)
KW  - Water (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:19968824
UR  - <Go to ISI:>//WOS:000274412500009
DO  - DOI:10.1111/j.1365-3040.2009.02090.x
UR  - https://juser.fz-juelich.de/record/9495
ER  -