An Albino Mutant of Blastocladiella emersonii: Comparative Studies of Zoospore Behaviour and Fine Structure

Abstract

S U M M A R YA stable, ultraviolet-induced, albino mutant of Blastodadiella emersonii Cantino and Hyatt is described. It differs from wild type in: (a), capacity to form brown resistant sporangia (RS), both as 2nd and 3rd generation RS in clones derived from 1st generation ordinary colourless (OC) plants, and as I st generation RS produced directly in response to exogenous bicarbonate; (b) the inhibition of growth by low concentrations of bicarbonate; (c) the longer generation time, stemming from a combination of decreased growth rate and delay in spore release until terminal sporangia have become unusually large; ( d ) the increased incapacity to discharge in situ on solid media with increasing temperatures above 23" ; (e), reduced motility of zoospores and increased tendency to become amoeboid and encyst prematurely; cf), certain changes in the fine structure and organization of mitochondria and their associated lipid sacs, y particles and the double membranes that surround nuclear caps and nuclei of spores chilled to low temperatures.

The Zoospore of Allomyces

“…Cantino & Horenstein (1956), Lovett (1963), Fuller (1966), Reichle & Fuller (1967), Cantino, Truesdell & Shaw (1968), Lessie & Lovett (1968), Shaw & Cantino (1969), Cantino & Truesdell (1970) and Truesdell & Cantino (1970) have presented an exhaustive, if not always consistent, description of the zoospores of Blastocladiella. The ultrastructure of the zoospores of Monoblepharella, a member of the third order of the Chytridiomycetes, the Monoblepharidales, has been described by Fuller (1966) and Fuller & Reichle (1968).…”