A rapid and economical method for hybrid purity testing of tomato (Lycopersicon esculentum L.) F 1 hybrids using ultrathin-layer isoelectric focusing of alcohol dehydrogenase variants from seedsIn the cultivated tomato (Lycopersicon esculenturn L.), two electrophoretic variants of the enzyme alcohol dehydrogenase (ADH) encoded by the alleles Adh-I and Adh-1' are found. A rapid and economic method for testing the hybrid purity of tomato F 1 seeds, based on the expected presence of Adh-1 alleles, was developed. The method is based on the analysis of the A D H variants by ultrathin-layer isoelectric focusing, p H range 3-10, of crude extracts from imbibed seeds, followed by enzyme activity staining. The isoelectric points (prs) of the ADH variants were estimated to be 5.5 and 5.7 for Adh-I+ and Adh-l', respectively. Using the procedure described and a newly developed sample applicator strip, it is possible for one person to routinely analyze 1 152 seeds per day using only a single electrophoresis unit. An investigation of a large number of inbred lines, both experimental and commercial hybrids, together with open-pollinated varieties, showed the potential of the method. Among F 1 hybrids, a higher frequency of the Adh-1 I allele was found than among open pollinated varieties, suggesting that F 1 hybrid breeding has resulted in a higher frequency of Adh-l I alleles by selection of linked genes.

No abstract

No abstract

No abstract

No abstract