Induction by ozone of ethylene production and an ACC oxidase cDNA in rice (Oryza sativa L.) leaves

Exposure to ozone at 1 mu l l(-1) for 6 h induced ethylene production in ri ce (Oryza sativa L. cv. Hitomebore) leaves. The stimulation of ethylene pro duction was detectable 2 h after the start of the exposure to ozone, and la sted for 6 h after the exposure. A 429-bp cDNA fragment encoding ACC oxidas e was obtained by RT-PCR from ozone-treated rice leaves. Its nucleotide seq uence and deduced amino-acid sequence had 97.2% and 94.4% identity, respect ively, to those of OS1A1COX, which was previously obtained from deepwater r ice. The abundance of the cDNA increased in accordance with the induction o f ethylene production by the exposure to ozone.