title: GROWTH AND MATING OF GONIUM PECTORALE (VOLVOCALES) IN DEFINED MEDIA(1).
abstract: Growth in defined media of 32 populations of Gonium pectorale was studied to learn more about the sexual isolation reported for this species. The 23 populations containing both mating types (+ & -) icere also studied for the ability to form zygotes in defined media. A preliminary study showed that some populations grew and reproduced sexually in a defined mineral medium, whereas others appeared to require exogenous organic materials for growth and/or zygote formation. The diverse reactions exhibited by the populations indicate physiological races which may explain, in part, the occurrence of sexual isolation.
authors.affiliation: Department of Botany, University of British Columbia, Vancouver, Canada.
authors.forename: J R
authors.initials: JR
authors.lastname: Stein