Indicated that null segregants lacking transgene have been obtained from the progeny of the backcross of transformants

Citrus disease resistance breeding has been advanced to introduce CTV resistance of trifoliate orange to citrus. Because the quality of the fruit of trifoliate ogate was low, backcross with citrus was necessary. In the case of citrus, it takes several years from flowering to obtaining next-generation seeds. Therefore, we generated transformants for the early flowering genes (citrus FLOWERING LOCUS T: CiFT) using CiFT co-expression vector construct and promoted generation. In Japan, it is difficult to plant transformants in the field. Therefore, it was decided to select null segregant lacking transgene from backcross progenies. In order to prove that the transgene has been completely removed, it is necessary to prove that no vector conract is present on the genome. Tthis matter was proved by CGH analysis. Wild type of trifoliate orange vs. wild type of trifoliate orange as control, wild type of trifoliate orange and vector contract as control, transgenic torifoliate orange by vector construct (T0), two null segregant lacking transgene in back cross generation 2nd, one transgenic segregant with transgene inserted in the genome in back cross generation 2nd, one null segregant lacking transgene in back cross generation 3rd, one transgenic segregant with transgene inserted in the genome in back cross generation 3rd