Premium
Interactions between atmospheric CO 2 concentration and phosphorus nutrition on the formation of proteoid roots in white lupin ( Lupinus albus L.)
Author(s) -
Campbell C. D.,
Sage R. F.
Publication year - 2002
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1046/j.1365-3040.2002.00883.x
Subject(s) - lupinus , phosphorus , phosphorus deficiency , photosynthesis , nutrient , chemistry , photosynthetic capacity , botany , zoology , horticulture , agronomy , biology , organic chemistry
Atmospheric [CO 2 ] affects photosynthesis and therefore should affect the supply of carbon to roots. To evaluate interactions between carbon supply and nutrient acquisition, the [CO 2 ] effects on root growth, proteoid root formation and phosphorus (P) uptake capacity were studied in white lupin ( Lupinus albus L.) grown hydroponically at 200, 410 and 750 µ mol mol −1 CO 2 , under sufficient (0·25 m m P) and deficient (0·69 µ m P) phosphorus. Plant size increased with increasing [CO 2 ] only at high P. Both P deficiency and increasing [CO 2 ] increased the production of proteoid clusters; the increase in response to increased [CO 2 ] was proportionally greater from low to ambient [CO 2 ] than from ambient to high. The activity of phosphoenol pyruvate carboxylase in the proteoid root, the exudation of organic acids from the roots, and the specific uptake of P increased with P deficiency, but were unaffected by [CO 2 ]. Increasing [CO 2 ] from Pleistocene levels to those predicted for the next century increased plant size and allocation to proteoid roots, but did not change the specific P uptake capacity per unit root mass. Hence, rising [CO 2 ] should promote nutrient uptake by allowing lupins to mine greater volumes of soil.