THE PROMOTER OF COCONUT FOLIAR DECAY-ASSOCIATED CIRCULAR SINGLE-STRANDED-DNA DIRECTS PHLOEM-SPECIFIC REPORTER GENE-EXPRESSION IN TRANSGENICTOBACCO

A full-length double-stranded DNA copy of the single-stranded circular DNA associated with coconut foliar decay virus (CFDV) was constructed . Full-length CFDV DNA and smaller fragments were transcriptionally fu sed to the beta-glucuronidase reporter gene and examined for promoter activity in vivo. In stably transformed tobacco plants, the CFDV DNA p romoter confered a tissue-specific expression pattern in that the repo rter gene was specifically expressed in the phloem tissue of the vascu lar system in stem, leaves and flower. These results are in agreement with the previously reported association of CFDV DNA with the phloem o f its coconut host plant.