Classes of True-Breeding Diploid Mutants Obtained After Colchicine Treatment of Sorghum Line, Experimental 3

Abstract

Colchicine treatment of seedlings of sorghum line, Experimental 3, has resulted in the production of true-breeding mutant lines which fall into specific types. Nine classes (two with subclasses based on variation in a single character) have been set up. Non-recurrent mutant lines (some resembling certain classes to a degree and others distinctly different) have also been obtained. Further work would be expected to produce both additional lines and additional classes. The composite nature of the mutants, the presence of classes, and the relationships between different classes and between certain classes and non-true-breeding mutants, all suggest that major chromosome changes are involved in their formation. These results contribute to the hypothesis that the mutants result from chromosome substitution (Sanders and Franzke, 1964).