Reaction of Certain Plant Growth-Regulators with Ion Exchangers

Abstract

Cation exchangers in the hydrogen cycle adsorbed much 2,4-D and its ammonium, calcium, and cupric salts, and in about equal amts. Little or no 2,4-D or its salts were adsorbed by cation exchangers in the Na or Ca form, but much was adsorbed by anion exchangers. Isopropyl N-phenyl carbamate (IPPC) was more strongly adsorbed than 2,4-D by cation exchangers in the H, Na, or Ca form, but much less was adsorbed by acid exchangers. Much less 2,4-D was adsorbed by Amberlite IR-100 H when the pH of the soln. was 3.3 than when it was 2.5 or lower. Solns. of NaCl, CaCl2, A1C13,6H2O, Na2,SO4, and Na3PO4,12H2O eluted less 2,4-D from Amberlite IR-100 H than did water. IPPC was eluted from IR-100 II by NaCl soln., and HC1 eluted 2,4-D from anion exchangers. When mixtures of 2,4-D, NH42,4-D, Ca(2,4-D)2, Cu-(2,4-D)2, IPPC, or 2,4,5-trichlorophenoxyacetic acid with Decalso or Zeo-Dur were leached, the different compounds were usually removed in about equivalent amts. Growth of plants in soils containing ion exchangers upon which NH42,4-D was adsorbed showed that much of adsorbed growth-regulator was non-toxic.