Factors Affecting Absorption and Translocation of Foliar Applied Phosphorus.

Publisher Website
Google Scholar
Abstract
A P32 spray application method proved superior to leaf vein injection and droplet methods with bean plants grown at 24[degree]C and 60% R.H. The amount of P translocated from the treated leaf in a 24-hour period increased as the amount applied increased; and it was independent of leaf area treated, except possibly at the highest concentration (30 m[image]), and of the leaf surface treated (upper or lower). More P was translocated from older (lower) leaves than from younger (upper) leaves (very young leaves did not export P), and the leaves contributed P to the root in proportion to their proximity to it and all leaves which exported P contributed approximately equal amounts to the stem apex. Translocation of applied P was greatest with NaH2PO4 and decreased with the following compounds: K2HPO4> K3PO4[image]Na2HPO4 [image] NH4HPO4[image] (NH4)2HPO4>H3PO4 (injury)> KH2PO4[image] Na3PO4- The amount of P translocated from a given compound appeared to be directly related to the drying time of the solution of the leaf. Glycerin increased the translocation from KH2PO4 to the level of NaH2PO4 but reduced the translocation from K2HPO4, probably because a complex was formed. Absorption of applied P (NaH2PO4) fell off markedly after about 30 hours, but 60% had been absorbed and 34.5% translocated out of the treated leaflet in 96 hours. Surface active agents (nonionic, anionic and cationic) were ineffective in increasing translocation of applied P.
Keywords

This publication has 3 references indexed in Scilit: