Movement of P, Zn, Fe and Mn to Rice Roots Growing in Soils

A greenhouse experiment conducted to study the movement of ions to roots using 5 soils of Nainital Tarai region showed clearly that the mass flow was found to be an unimportant procsss in the transport of P, Zn and Fe to rice roots grown in soils at about field capacity. However, for Mn it is found to be a fairly important process. Irrespective of varieties, moisture regimes, soils and ions, root interception was again found to be an unimportant process. Contribution of mass flow in soils under submerged condition was always more as compared to that under field capacity. Mass flow was found to be an important process for Fe and Mn. Apparent diffusion is found to be the major process of P, Zn, Mn and Fe transport to rice grown at field capocity. More than 100 per cent contribution of mass flow of Fe and Mn under submerged condition indicated that accumulation of ions on root surface or their back diffusion away from roots may take place.