Abstract:

Three alloploids with different ploidies from interspecific hybridization in Cucumis [interspecific hybrids F1 (2n = 2x = 19, HC), allotriploid (2n = 3x = 26，HCC), and allotetraploid C. hytivus (2n = 4x = 38，HHCC)] and their parents were used for the comparative studies on expression pattern of peroxidase (POD), glutamate dehydrogenase (GDH), and aspartate aminotransferase (AAT). The results showed that the zymograms in the alloploids were similar in band number and band distribution. The intensity of band in these allopolyploids, however, presents significant difference, which was caused by genome dosage. In AAT zymogram, the intensity of band was positively correlated with ploidy level. In POD and GDH zymogram, however, the intensity of band was negatively correlated with ploidy level. It was indicated that the coherence between genome dosage and isozyme expression pattern would be opposite in different enzyme systems. These data will be helpful to illuminate the morphological changes caused by the polyploid level.

Key words: Cucumis, isozyme, cucumber, genome dosage, allopolyploid