Discrimination of citrus tristeza virus (CTV) strains using Mexican lime/citrange Troyer combinations (Citrus poncirus/Citrus trifoliata x Poncirus sinensis)

Two strains of citrus tristeza virus (CTV) were studied for six years in Yaounde in the forest zone of Cameroon. These strains, SNCL2 and SNCL4, were characterized on Lisbon lemon in Nyombe in the littoral zone of Cameroon. They were inoculated onto combinations of Mexican lime/citrange Troyer. The virulent strain SNCL2 induced a lower lateral growth of the trunk of stocks and scions of six years old combinations. These observations were made three years after inoculation. Tristeza symptoms could not allow for differentiation between the two strains of CTV.