Thirty seedlings having missing, extra or deformed cotyledons were isolated from 30,000 screened. One, AAS-1 never set seed but is still alive and is being used as a pollen donor in order to rescue the mutation as a heterozygote. Thirteen other putative mutants were grown to maturity and rescreened in the next generation. All but two of these plants appeared normal in the next generation and were not investigated further. The remaining 2 mutants were characterized visually at the light and SEM level. AAS-1 had copious numbers of normal looking trichomes covering the first several true leaves (Figure 4.1). This phenotype has not previously been described in the literature. Mutant AAS-2 was a green tricot but seedlings in the next generation were 78% albino. [Four of those green plants were allowed to self pollinate and the albino characteristic is retained in the third generation.] Mutant AAS-6 displayed a variety of deformities in the early seedling stage including fusion of cotyledons and true leaves, and extra cotyledons (Figure 4.2). Based on these observations the expression of the mutant gene in AAS-6 was hypothesized to occur at least as early as the globular heart stage of embryogenesis.
All contents copyright (C) 1995, Jonathan D. Monroe. All rights reserved.
Revised: December 22, 1995
URL: http://csm.jmu.edu/biology/courses/bio455_555/atlab/dev.html