ACCUMULATION OF PHENYLPROPANOIDS IN THE COTYLEDONS OF MORNING GLORY (PHARBITIS-NIL) SEEDLINGS DURING THE INDUCTION OF FLOWERING BY LOW-TEMPERATURE TREATMENT, AND THE EFFECT OF PRECEDENT EXPOSURE TO HIGH-INTENSITY LIGHT

Extracts from the cotyledons of seedlings of Pharbitis nil strain 'Vio let' cultured at low temperature, which induces their flowering even i n continuous light, with or without precedent exposure to high-intensi ty light, which shortens the period of low temperature required for fl owering, were analyzed by HPLC for substances correlating with the flo wer-inducing process. The content of two phenylpropanoids were found t o increase during the low-temperature, and were identified as 3-O-feru loylquinic acid and dehydrodiconiferyl alcohol-13-O-beta-D-glucoside. The increase was more rapid in the cotyledons exposed to high-intensit y light before the low-temperature. This suggests that the accumulatio n of these compounds is correlated to the promotive effect of high-int ensity light on the flower-induction by low temperature.