Impact of low temperature on superoxide dismutase (SOD) activity of frost resistant hybrids of potatoes

The isoenzymes changes of superoxide dismutase (SOD) and photosynthetic pigments in frost resistant somatic hybrids of Solanum tuberosum L. and S. commersonii Dun. in vitro culture after low (+6°C) temperature adaptation were investigated. There have discovered interspecific differences of SOD isoenzyme profiles in paternal forms – S. commersonii, S. tuberosum. The hybrids inherited the SOD profiles with 6 isoforms from the recipient S. tuberosum cv. ‘Matilda’, while from donor, a wild species S. commersonii, SOD-1 isoenzymes were inherited. However, the SOD activity studies showed that SOD activity of the interspecific hybrids was higher than of S. tuberosum cv. ‘Matilda’, but lower than of S. commersonii Dun. species. After 14 and 21 days of adaptation in all plants the reduction of photosynthetic pigments and increase in the SOD activity were observed, but in the hybrid H323 SOD activity was slightly decreasing. Probably, the reduction of isoenzymatic SOD activity in the hybrid H323 is not completely related with the adaptation to low temperature inherited from S. commersonii. High level of SOD activity in the hybrid H188 allow the statement that, perhaps, SOD isoenzymes participated in the process of plant adaptation to low temperature