Ajs. Mcdonald et al., PLANT NUTRITION, DRY-MATTER GAIN AND PARTITIONING AT THE WHOLE-PLANT LEVEL, Journal of Experimental Botany, 47, 1996, pp. 1245-1253
Differential flows of photoassimilate result in patterns of dry matter
distribution among plant organs. The extent to which these patterns a
re dependent on the flux of different mineral nutrients entering the r
oot and the extent to which the distribution of dry matter in the whol
e plant is affected by differentials in nutrient (primarily nitrate) f
lux among parts of the root system is considered. It is concluded that
patterns of dry matter distribution and nutritional status may depend
on how nutrient supply has been manipulated about the root. Where the
flux density of nutrient has been decreased and has become limiting t
o plant growth, two categories of response have been observed. In the
case of N, P or S, limiting flux density results in a proportionately
greater amount of plant dry matter in roots than is found at higher fl
ux densities, This contrasts with the case of limiting K, Mg or Mn sup
ply, where proportionately less plant dry matter is found in roots at
lower nutrient flux densities than at higher flux densities. In the ca
se of N, particular attention is paid as to how sink strength may be r
elated to differences between root and leaf cells in their capacity fo
r loosening and synthesis processes in the primary cell wall.