Abstract: Total RNA was extracted from petals of Carnation (Dianthus caryophyllus L.) and reverse transcripted to first strand of cDNA.For getting the 1-Aminocyclopropane-Carboxylic acid Oxidase (ACO) cDNA, a pair of primer was designed and synthesized according to the sequence reported. The PCR product of the ACO cDNA was obtained by using the first strand of cDNA as template. This product was ligased to pGEM -T easy vector and sequenced. The sequencing clata showed that the PCR produes. Comparation of the cDNA sequence from this experiment with that reported by GenBank L35152 indicated the homology was 100%. We give the results that this ACO gene among the species of Dianthus caropyllus L.is highly conserved. The ACO gene antisense sequence was then inserted between the CaMv 35S promoter and NOS terminator into the expression vector pBI121.This expression vector called pBO; Then the flower-spe-cific promoter PchsA was first inserted into the sites of the expression vector pBI121/HindIII+Xbal. This recombinant plasmid called pCHB, then inserted the ACO antisense gene into the sites of the plasmid pCHB/Xbal+SstI.Hence the antisense plant expression vector pCBO was constructed.

Key words: Carnation