Ascorbate Metabolism in Potato Leaves Supplied with Exogenous Ascorbate

Tsuyoshi Imai, Alison H. Kingston-smith, Christine H. Foyer*

*Awdur cyfatebol y gwaith hwn

Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

24 Dyfyniadau(SciVal)

Crynodeb

Photosynthesis and leaf ascorbate were measured in potato (Solanum tuberosum L.) plants grown in low light and then transferred to high light. Total foliar ascorbate content in low light-grown plants was 4.72 ± 0.42 μmol mg -1 chl. Over 80% of the ascorbate pool was found in the reduced form irrespective of position on the stem. No statistically-significant light-dependent effects were observed. Leaf discs supplied with [ 14C]- ascorbate in the dark showed significant ascorbate uptake such that after a 16 h incubation over half of the total ascorbate pool in the discs was labelled [ 14C]-ascorbate. No ascorbate efflux from the leaves occurred during the period of [ 14C]-ascorbate uptake. The total amount of ascorbate did not increase, however, implying modified ascorbate turnover. The turnover of the [ 14C]-ascorbate in the leaves occurred at similar rates in both light and darkness. Little degradation of labelled ascorbate was observed, suggesting that uptake of exogenous ascorbate leads to inhibition of de novo ascorbate biosynthesis in potato leaf discs.

Iaith wreiddiolSaesneg
Tudalennau (o-i)171-179
CyfnodolynFree Radical Research
Cyfrol31
Rhif cyhoeddiS1
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 01 Ion 1999

Ôl bys

Gweld gwybodaeth am bynciau ymchwil 'Ascorbate Metabolism in Potato Leaves Supplied with Exogenous Ascorbate'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.

Dyfynnu hyn