Studies on Phytocides II. Tests of Chlorinated Aryloxymethylphosphonous and Phosphonic Acids As Poisons and Auxins

Abstract

Tests were made on pea epicotyls or oat coleoptiles with o-chloro-, p-chloro-, 2,4-dichloro-, and 2,4,5-trichlorophenoxymethylphosphonous acids. The first compound behaved like a weak auxin, the third like an inactive substance or antiauxin (depending on the test), and the remainder like anti-auxins. The compounds usually showed some toxicity, which was far less than that of the corresponding carboxylic acids.