Inheritance of Resistance to cucumber Mosaic Virus in a Transgenic Tomato Line Expressing the Coat Protein Gene of the White Leaf Strain

摘要

In tomato (Lycopersicon esculentum Mill.), the coat protein (CP) gene of the white leaf strain of cucumber mosaic virus (CMV-WL) conferred a high level of resistance against American, Asian, European, and Oceanian strains belonging to both sero-groups of CMV. An analysis of genetic populations deriving from crosses and back-crosses of a homozygous CMV-resistant tomato line (TT5-007-11) with susceptible cultivars revealed that (1) the high level of resistance is conferred by a single dominant gene to which the symbol Cmv is assigned; (2) in grafts between CMV-resistant and -infected plants, the resistant plants developed systemic symptoms, indicating that they are not immune; (3) the CMV resistance is independent of the virus inoculum titer, and it can be effectively used for the production of F1 commercial hybrids; (4) the two markers, neomycin phosphotransferase II (NPT-II) and (β-glucuronidase (GUS), present in transgenic plants are not completely reliable for predicting resistance; and (5) Cmv confers resistance to most CMV strains containing satellltes (RNA5). but one mutant satellite derived from CMV-WL infected transgenic plants. This is the first report of a satellite that can interfere with the function of a CP gene. The valuable breeding line TT5-007-11 is resistant also to tobacco mosaic virus (Tm-22), Verticillium wilt, and Phytophthora infestans (Race 0)