Psyllium is a common name used for the plant genus Plantago. In western countries, dietary fiber from psyllium has been used extensively as both pharmacological supplements and food ingredients.

Plantago coronopus, commonly known as buckshorn plantain ("diabelha" in Portugal), is a medicinal halophyte belonging to the genus Plantago L., the largest of the Plantaginaceae family (Castroviejo et al., 2009; Ksouri et al., 2012).

The genus Plantago from Plantaginaceae family appears to be a good model for comparative studies on the responses to salt stress and shows an intermediate degree of salt tolerance, growing at concentrations of up to 150mm NaCl [3,8] and could cumulatively remove considerable amounts of salt from the soil [21, 30].

To determine whether gene transfer takes place in the opposite direction--from parasite to host--Palmer's team compared several genes from different species of the common weed genus Plantago with those in parasitic flower species of the Bartsia and Cuscuta genera.