The Parasitism of Pedicularis lanceolata Michx., a Root Hemiparasite

LACKNEY, V. K. (Dept. Biology, Univ. Akron, Akron, Ohio 44325). The parasitism of Pedicularis lanceolata Michx., a root hemiparasite. Bull. Torrey Bot. Club 108: 422-429. 1981.-Upon germination, seedlings of the swamp lousewort, Pedicularis lanceolata Michx., require hosts for continued development. Without hosts seedlings are stunted and chlorotic, whereas seedlings planted with clover (Trifolium incarnatum L.) or wheat (Triticum aestivum L.) as hosts were tall with expanded green leaves. In sterile culture, seedlings on a mineral nutrient medium with a low pH had growth similar to seedlings attached to hosts. At a higher pH or when the medium was supplemented with sucrose, fructose, glucose, casein hydrolysate, glutamine, kinetin, gibberellic acid or indoleacetic acid growth was stunted. It is therefore probable that P. lanceolata relies on a host for an increased supply of water and minerals with little reliance on a host for organic compounds.