Active Transport of Salt into Plant Tissue

The topic of active uptake and transport of salt in its many aspects has received meticulous and extensive treatment in recent years both in this journal (9, 27, 31, 72) and elsewhere (37, 83, 103, 104). Furthermore, a thoroughgoing dealing specifically with accumulation and transport in plants has recently been published (93). What follows, therefore, is not meant to provide an addendum of the most recent contributions to the field, but rather represents an attempt to consolidate and interpret a variety of observations, some venerable, some new, dealing with certain specialized aspects of salt uptake and transport which are particularly plant physiological in nature. Consequently the treatment may often prove emphatic, if all-inclusive, and will sometimes repeat in special context what others have said before. Absorption and uptake will be used as general terms describing ion and salt penetration of whatever kind into cells, tissues or organs. Active uptake and accumulation will imply metabolically implemented transport into the cell through a diffusion barrier, while adsorption will have usual physical-chemical connotations which will be defined more explicitly in context.