All known Castilleja species are
hemiparasites capable of utilizing broad range of hosts, yet nothing is known about the host(s) of C.
Growth, gas exchange and water use efficiency of the facultative
hemiparasite Rhinanthus minor associated with hosts differing in foliar nitrogen concentration.
Transfer of pyrrolizidine and quinolizidine alkaloids to Castilleja (Scrophulariaceae)
hemiparasites from composite and legume host plants.
The other species are arboreal (20%), shrubs (16%), subshrubs (11%), vines (8%), small trees (3%), epiphytes and lianas (2% each) and
hemiparasites (1%).
Both partial defoliation of the host plant Agrostis capillaris, especially when timed to a certain developmental phase of the parasitizing Rhinanthus serotinus plant, and soil quality were shown to influence growth and flower production of the
hemiparasite. The better growth of hosts in mould led to a higher number of flowers produced by the
hemiparasites compared to the situation in sandy soil.
Only 25 species of epiphytes and 11 species of
hemiparasites were reported (Table 2; Fig.
This family includes eight genera of root
hemiparasites that damage crops.
Phoradendron californicum are perennial, dwarf
hemiparasites which once established, rely entirely upon their hosts for their supply of water and various mineral nutrients (Hollinger 1983).
Phoradendron juniperinum (juniper mistletoe) are autotrophic
hemiparasites inhabiting branches of higher vascular plants (Kuijt 1969; and Calder and Bernardt 1983).
Confusion is introduced by statements that Cuscuta and Cassytha are holoparasites when, in fact, only some species of dodder are holoparasitic and all species of Cassytha are
hemiparasites. The relevant series of papers on Cuscuta physiology by Wolswinkel were missed.
These include applying these methods to plants with different morphologies and life spans, the lack of suitable methods that can be used to screen large number of plants for some types of measurements, and the problem of dealing with mutualistic associations such as mycorrhizae, epiphytes, and
hemiparasites. The editors also provide a wish list of tests that they would have liked to include, but for which they were unable to find suitable methods.