XVI International Botanical Congess

Two models are proposed that account for the impact of parasitic angiosperms on their host. The first is driven by host-parasite source-sink relation and is illustrated by the impact of Orobanche infecting tobacco and tomato. In these systems, difference in productivity between uninfected and infected plants can be accounted or by the carbon allocated to the parasite. In addition to this model, in some systems, most notable interactions between Striga and cereals, such source-sink interactions are subjugated by additional effects. The mechanistic bases of such response are still unkown and hypotheses are presented on the basis of the impact of Striga on the metabolism of its host.