SIMILARITY AMONG PLANT GROWTH INHIBITORS PRODUCED BY PENICILLIUM THOMII, P. OXALICUM AND BYSSOCHLAMYS NIVEA.

Abstract

WHEN seedlings of Phaseolus vulgaris var. Black Valentine were treated on one of the simple leaves with culture filtrates of P. thomii, P. oxalicum, or B. nivea (Arachniotus trisporus), subsequent growth of the plants was inhibited more or less selectively on the treated side1. As a result, the first, second, and often the third trifoliolate leaves were asymmetrical. In severe cases, both sides of the trifoliolate leaves were inhibited. ‘Asymmetrin’ has been proposed as a name for the growth inhibitor produced by these fungi2. Preliminary investigations showed that culture filtrates of the three fungi produced a red-purple colour when treated with ferric chloride. Because of their similar effects on bean plants and coloration with ferric chloride, the relationship of the inhibitors to each other and to the ferric chloride reactive compounds was investigated.