INDUCTION OF HOMOLOGOUS LOW-TEMPERATURE AND ABA-RESPONSIVE GENES IN FROST RESISTANT (SOLANUM-COMMERSONII) AND FROST-SENSITIVE (SOLANUM-TUBEROSUM CV BINTJE) POTATO SPECIES

A DNA fragment corresponding to a low-temperature- and ABA-responsive gene (Scdhn1) was amplified by PCR from genomic DNA of a wild, frost-r esistant potato species, Solanum commersonii. A homologous gene (Stdhn 1) was identified in Solanum tuberosum cv. Bintje, a frost-sensitive d omesticated potato cultivar. The expression of the gene was studied du ring low temperature and ABA treatments in both Solanum species. The a nalysis revealed that both low temperature and ABA lead to the accumul ation of a 1 kb transcript that corresponded to the PCR fragment. The induction of the gene was relatively rapid and maximum amounts of the transcripts were detected already after 1 day and 7 h of treatment wit h low temperature and ABA, respectively. Previous results have shown t hat there is no increase in the amount of endogenous ABA in S. tuberos um during low-temperature treatment, which indicates that two independ ent signalling pathways lead to the induction of this gene.