Abstract
Putative D genome donors to Aegilops crassa (2n=4x=28, DDMcrMcr and 2n=6x=42, DDD2D2McrMcr) and Ae. Vavilovii (2n=6x=42, DDMcrMcrSpSp) were studied for esterase isozyme similarities. Esterase isozymes examined by gel isoelectrofocusing reveal no inter- or intraspecific variation in Ae. crassa and Ae. Vavilovii. The putative parents, Ae. Squarrosa (2n=2x=14, DD) and Ae. comosa (2n=2x=14, MM), each exhibit three isozyme phenotypes. The natural tetraploid form of Ae. crassa has an isozyme pattern corresponding to a mixture of esterases from type 2 squarrosa and type 1 comosa. We conclude from this that the D genome donor to Ae. Crassa 4x is type 2 squarrosa. The hexaploid form of Ae. Crassa possesses the same D genome as the tetraploid form, suggesting a duplication of the type 2 squarrosa D genome. Moreover, the D genome of the hexaploid form is the same as the D genome of Triticum aestivum cv. Chinese Spring (bread wheat, 2n=6x=42, AABBDD). It was also found that the putative D genome donor to Ae. Vavilovii corresponds to type 2 squarrosa.
