The Ac/Ds Transposon System from Maize as a Tool for Generating Mutant Phenotypes in Tomato (Lycopersicon Esculentum)

ABSTRACT

A non-targeted transposon tagging experiment was performed in tomato (Lycopersicon esculentum). The Ac/Ds transposon system from maize was used. To generate a transposon tagging population, tomato genotypes ET 570 and SLJ10512 were used. The ET 570 genotype contains a single homozygous T-DNA with Ds at the end of the long arm of chromosome 3. The SLJ10512 genotype carries a stabilized Ac that can activate Ds in trans. This tagging population was tested at the seedling level (Van der Biezen et al., 1996) and two phenotypic mutants were found that co-segregated with a Ds insertion: feebly (fb) and yellow jim (yj). In this work, performed under field conditions, all stages of individual plant development were screened for mutant phenotypes. Out of 269 families, with in total approximately 400 unique transposed Ds elements, 5 different phenotypes were observed. One of the phenotypes, fruit distortion, segregated in a Mendelian fashion. Plants with the fruit distortion phenotype did not produce seeds. In the case of the other 4 phenotypes, green spots, dark green leaves, dwarf and partially hairless plant only one phenotypic mutant plant per family was obtained and, thus, could not be classified. Phenotypic mutants, obtained from this transposon tagging experiment, that show linkage to the Ds insertion, might be used to isolate the genes responsible for the mutant phenotypes.