Zea mays L. (cv Dea) plants grown to the stage of stalk elongation, were allowed to assimilate (13)CO(2) and (15)N-nitrates from 45 to 53 days after sowing. Isotopic abundances in labeled nutrients were slightly enriched compared to natural abundances. The new C in plant was acropetally distributed and the new N was preferentially accumulated in the sheath and stalk in the medium region. C input was 25-fold higher than N input. The new C in total plant C was 20%, whereas it was 10% for N. The stalk acted as a major sink because it accumulated, respectively, 27.5 and 47.5% of the C and N inputs. The new C in soluble carbohydrates was 76% in growing organs (upper stalk) and only 39% in source leaves, whereas it was 43% and 13% in starch, respectively. New N in nitrates+amino-acids spanned in the range from 20% (leaf) to 50% (stalk). New C and N in soluble proteins were, respectively, 13.4 and 3.8% in leaves, 8.8 and 9.6% in stalk, and 8.7 and 14.3% in roots. In the middle stalk and leaves, the proteins and carbohydrates represent an equivalent C and N source for remobilization.
Zea mays L. (cv Dea) plants grown to the stage of stalk elongation, were allowed to assimilate n class="Chemical">(13)CO(2) and (15)N-nitrates from 45 to 53 days after sowing. Isotopic abundances in labeled nutrients were slightly enriched compared to natural abundances. The new C in plant was acropetally distributed and the new N was preferentially accumulated in the sheath and stalk in the medium region. C input was 25-fold higher than N input. The new C in total plant C was 20%, whereas it was 10% for N. The stalk acted as a major sink because it accumulated, respectively, 27.5 and 47.5% of the C and N inputs. The new C in soluble carbohydrates was 76% in growing organs (upper stalk) and only 39% in source leaves, whereas it was 43% and 13% in starch, respectively. New N in nitrates+amino-acids spanned in the range from 20% (leaf) to 50% (stalk). New C and N in soluble proteins were, respectively, 13.4 and 3.8% in leaves, 8.8 and 9.6% in stalk, and 8.7 and 14.3% in roots. In the middle stalk and leaves, the proteins and carbohydrates represent an equivalent C and N source for remobilization.
Authors: P K Smith; R I Krohn; G T Hermanson; A K Mallia; F H Gartner; M D Provenzano; E K Fujimoto; N M Goeke; B J Olson; D C Klenk Journal: Anal Biochem Date: 1985-10 Impact factor: 3.365
Authors: B Hirel; P Bertin; I Quilleré; W Bourdoncle; C Attagnant; C Dellay; A Gouy; S Cadiou; C Retailliau; M Falque; A Gallais Journal: Plant Physiol Date: 2001-03 Impact factor: 8.340