Isolement d'une nouvelle souche dePhycomyces. Etude de ses caractéristiques morphologiques et de ses besoins en facteurs de croissance

Summary

Starting from a strain ofPhycomyces «Berne» used at the Botanical Institute, we have isolated, with the aid of one-spore cultures, a new strainS2, the morphology and physiology of which are different from those of the original strain. Under definite conditions of culture, pyrimidine added to a synthetic medium is sufficient as an exogenous growth-factor. TheS2 strain is characterized by a rounded spore and by a type of growth called “ball-like”. The morphological differences between the ellipsoid spore of strainS1 and the rounded spore of strainS2 are constantly accompanied by an essential difference in the power of synthesis of the two strains described.