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The efficiency of cell-to-cell virus movement is important in determining pathogenicity, virulence and, in some cases, the host range of a plant virus (reviewed by Atabekov & Taliansky, 1990 ;Maule, 1991). When the efficiency of the transport function and the rate of virus movement are reduced, the plant acquires a certain level of resistance to virus infection.Production of dysfunctional or partially active movement proteins (MP) in transgenic plants is assumed to confer resistance to the wild-type (wt) virus by competition between wt virus-coded MP and the preformed modified MP (mMP). In support of this assumption, it has been reported that transgenic tobacco plants which produce a non-functional MP of tobacco mosaic virus (TMV) acquire resistance to TMV infection (Malyshenko et al., 1993 ;Lapidot et al., 1993). In addition, transgenic plants expressing non-functional TMV MP were resistant to several distantly related or unrelated viruses (Lapidot et al., 1993 ;Cooper et al., 1995). These results suggest

Coconut foliar decay virus (CFDV) contains the single-stranded circular DNA molecules of 1291 nucleotides which were found to replicate autonomously in the cells of the diseased palms. The special features of the CFDV DNA sequence, including putative secondary structure and the distribution of the inverted repeat motifs, are investigated with computer-assisted prediction methods. It is evident that the structural principle of the branched series of long and short double helixes interspersed by short non-helical regions is existed for CFDV virion DNA. The total degree of base pairing is near 62%. We have also predicted the presence of several sequence elements formed by inverted repeat motifs which are potentially capable of binding the eukaryotic transcriptional regulatory factors.