TY - JOUR

T1 - Physiological disturbances caused by high rhizospheric calcium in the calcifuge Lupinus luteus.

AU - de Silva, D. L. R.

AU - Ruiz, L. P.

AU - Atkinson, C. J.

AU - Mansfield, T. A.

PY - 1994

Y1 - 1994

N2 - A detailed study of the calcifuge Lupinus Iuteus L. (yellow lupin) has been carried out in an attempt to explain its poor performance in the presence of high concentrations of rhizosphenc calcium. Plants were grown on two different calcium regimes, 1 or 15 mol m– Ca and, after an establishment period, measurements were made of the rate of leaf extension, final length of the leaflets and the leaf gas exchange. In addition, the distribution of calcium within the leaf tissue was investigated. At 15 mol m–3 Ca, leaflet length at full expansion was reduced as a consequence of reduced extension rate and a decline in cell wall extensibility. Transpiration in excised leaves, assayed gravimetrically, was significantly reduced in plants grown in high calcium. Similar results were also obtained from gas exchange measurements. Analysis of A/C, curves indicated that in plants grown in high [Ca] there was a substantial reduction in net assimilation over a range of concentrations of CO2 X-ray microanalysis revealed that a large amount of cal cium delivered in the xylem sap is retained in the mesophyll tissue, and most of that reaching the epidermal tissue is not found in the guard cells but in the cells adjacent to them, which in this species are not anatomically distinct as ‘subsidiary’ cells.

AB - A detailed study of the calcifuge Lupinus Iuteus L. (yellow lupin) has been carried out in an attempt to explain its poor performance in the presence of high concentrations of rhizosphenc calcium. Plants were grown on two different calcium regimes, 1 or 15 mol m– Ca and, after an establishment period, measurements were made of the rate of leaf extension, final length of the leaflets and the leaf gas exchange. In addition, the distribution of calcium within the leaf tissue was investigated. At 15 mol m–3 Ca, leaflet length at full expansion was reduced as a consequence of reduced extension rate and a decline in cell wall extensibility. Transpiration in excised leaves, assayed gravimetrically, was significantly reduced in plants grown in high calcium. Similar results were also obtained from gas exchange measurements. Analysis of A/C, curves indicated that in plants grown in high [Ca] there was a substantial reduction in net assimilation over a range of concentrations of CO2 X-ray microanalysis revealed that a large amount of cal cium delivered in the xylem sap is retained in the mesophyll tissue, and most of that reaching the epidermal tissue is not found in the guard cells but in the cells adjacent to them, which in this species are not anatomically distinct as ‘subsidiary’ cells.

KW - Calcium

KW - calcifuge

KW - Lupinus luteus

KW - stomata

KW - leaf growth

U2 - 10.1093/jxb/45.5.585

DO - 10.1093/jxb/45.5.585

M3 - Journal article

VL - 45

SP - 585

EP - 590

JO - Journal of Experimental Botany

JF - Journal of Experimental Botany

SN - 1460-2431

IS - 5

ER -