Transport of phloemmobile substances from compatible host plants into the parasite Cusucta reflexa was investigated and based on our results, a model was developed. Leaves from Pelargonium zonale parasitised with Cuscuta reflexa were used to characterise source-sink relations and partitioning of assimilates and xenibiotic substances during the development of phloem contact between host and parasite. For translocation of phloemmobile fluorescent dyes [5,6 carboxyfluorescein and 8-hydroxypyren-1,3,6-trisulforic acid] and potato virus X expressing GFP host-parasit-systems Nicotiana benthamiana-Cuscuta reflexa were used. For translocation of green fluorescent protein (GFP) we used transgenic Nicotiana tabacum cv. Sumsai as a host, expressing GFP under the control of AtSUC 2 promotor from Arabidopsis thaliana. The results of the translocation experiments with biotic and abiotic phloemmobile substances, fluorescent dyes, viruses and GFP indicate, that compatible host plants and Cusucta reflexa develop a symplastic phloem connection.