the present invention relates to nucleic acid molecules found in the genome of the citrus leprosis virus , which is associated to citrus leprosis disease . the cloned cilv nucleic acid molecules can be used as probes or can be used to design oligonucleotide primers useful in assays , such as a polymerase chain reaction , for detecting the presence of cilv in biological samples , particularly leaves , roots and other tissues or organs of plants , such as plants from the genera citrus and poncirus . the invention comprises introducing the mentioned nucleic acid molecules in cloning vectors and cloning the recombinant nucleic acid molecules in cells , such as prokaryotes , and eukaryotes . the cloned cilv nucleic acid molecules are expressed in cells to provide immunogenic proteins which can be used to raise antibodies against the cilv , which can then be used to detect the presence of the cilv virus in biological samples . it also comprises the nucleic acid molecules represented in seq id nos . 5 and 8 , in whole or part , as well as transgenic plants , such as monocots and dicots , containing the cilv nucleic acid molecules , in any kind of combination , so that expression increases resistance to cil disease .