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Genetic analysis with T-DNA mutants often brings difficulties resulting from instability of the transgenic phenotype. In this work three different Arabidopsis thaliana T-DNA embryonic lethals and one T-DNA morphological mutant were analyzed in F2 progeny after 15 different crosses with marker lines for individual chromosomes. F2 analysis of 44 segregation ratios revealed segregation distortion of similar character consisting in abnormal excess of nontransgenic plants to the detriment of transgenic ones. We quantified this phenotypic drift ( d) on the basis of phenotypic ratios given the respective formulas. The d values indicate the rate of F1 gametes which loose the T-DNA mutation or ability of its expression. The obtained d value were relatively high, 0.4 to 0.9 for individual crosses. It makes the standard recombination analysis with insertional mutants very problematic or even impossible. [ABSTRACT FROM AUTHOR]

Collection of the T-DNA tagged lines of Arabidopsis thaliana have been created by Agrobacterium-mediated root transformation. Transgenic lines produced by this method have been screened for morphogenic mutations. A flower mutation with increased number of stamens and carpels (scaf1) was identified. This mutation has similar but weaker phenotype than the known mutant superman. Two mapping procedures, with visible and molecular markers, were used to locate scaf1 flower mutation. Genetic analysis showed that this mutation is located on chromosome 3 near gl1 gene. It is probably one of the SUPERMAN epigenetic alleles. [ABSTRACT FROM AUTHOR]