Abstract
To investigate changes in polyamine level in rice seedlings treated under various environmental stresses and plant hormones, polyamines are extracted and subjected to HPLC analysis. The HPLC analysis revealed that level of a major polyamine, putrescine, is significantly increased in rice seedlings in response to chilling and submergence stresses as well as ABA. It is well known that arginine decarboxylase (ADC) and ornithine decarboxylase (ODC) are involved in putrescine biosynthesis in plants. To test either of ADC or ODC is responsible for the increase in putrescine level in rice seedlings treated under the stresses and ABA, we have isolated ADC and ODC genes from rice by RT-PCR. The gene-specific probes were prepared from 3'-UTR of the ADC and ODC genes for northern analysis. Results of northern analysis with the gene-specific probes are discussed in relation to the increase in putrescine level in rice seedlings treated under chilling and submergence stresses.
