LICHEN SUBSTANCES AND THE PLANT GROWTH. III THE EFFECTS OF ROCCELLIC ACID ON THE GROWTH OF GERMLINGS OF ULVA LACTUCA L.

Abstract

  Reproductive elements of Ulva lactuca L. (Ulvales, Chlorophyta) develop germlings when growth in a nutrient medium containing roccellic acid, as sodium salt, at various concentrations; its effect was compared with the one of IAA 10^-5 M. The length ratio of sporophytes and gametophytes increases in higher percentages such as 89,3% and 55,0% in 10^-7 M roccellic acid concentration. The development of rizoids, in number and in length, was obtained at this same concentration.