Studies on Plant Growth-Regulating Substances II. Synthetic Compounds Inducing Morphogenic Responses in the Tomato Plant

Abstract

Certain growth-regulating chemicals when applied in small quantities to plants are well- known to influence subsequent growth. In the experiments described in this paper, over thirty substances have been applied to tomato plants and the abnormalities in growth and development arising from these treatments are recorded. The compound a-(2-naphthoxy)-phenyl- acetic acid (NPA) produced a variety of effects, one of which was the appearance of flower trusses in terminal positions on the plant. This abnormality has previously only been recorded in plants treated with 2:3: 5-triiodobenzoic acid (TIB). Comparative experiments have shown TIB to be more active than NPA in this respect.