Orobanche: A plant genus of the family OROBANCHACEAE. Lacking chlorophyll, they are nonphotosynthetic parasitic plants. The common name is similar to Broom or Scotch Broom (CYTISUS) or Butcher's Broom (RUSCUS) or Desert Broom (BACCHARIS) or Spanish Broom (SPARTIUM) or Brome (BROMUS).Striga: A plant genus of the family Orobanchaceae that is parasitic on the roots of other plants. Members contain the flavones, APIGENIN and LUTEOLIN.Plant Exudates: Substances released by PLANTS such as PLANT GUMS and PLANT RESINS.Germination: The initial stages of the growth of SEEDS into a SEEDLINGS. The embryonic shoot (plumule) and embryonic PLANT ROOTS (radicle) emerge and grow upwards and downwards respectively. Food reserves for germination come from endosperm tissue within the seed and/or from the seed leaves (COTYLEDON). (Concise Dictionary of Biology, 1990)Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)Helianthus: A genus herbs of the Asteraceae family. The SEEDS yield oil and are used as food and animal feed; the roots of Helianthus tuberosus (Jerusalem artichoke) are edible.Vicia sativa: A plant species of the genus VICIA, family FABACEAE. The seed is used for food and contains THIOCYANATES such as prunasin, cyanoalanine, cyanogen, and vicine.Trifolium: A plant genus of the family FABACEAE.Lactones: Cyclic esters of hydroxy carboxylic acids, containing a 1-oxacycloalkan-2-one structure. Large cyclic lactones of over a dozen atoms are MACROLIDES.Autotrophic Processes: The processes by which organisms use simple inorganic substances such as gaseous or dissolved carbon dioxide and inorganic nitrogen as nutrient sources. Contrasts with heterotrophic processes which make use of organic materials as the nutrient supply source. Autotrophs can be either chemoautotrophs (or chemolithotrophs), largely ARCHAEA and BACTERIA, which also use simple inorganic substances for their metabolic energy reguirements; or photoautotrophs (or photolithotrophs), such as PLANTS and CYANOBACTERIA, which derive their energy from light. Depending on environmental conditions some organisms can switch between different nutritional modes (autotrophy; HETEROTROPHY; chemotrophy; or PHOTOTROPHY) to utilize different sources to meet their nutrient and energy requirements.Host-Parasite Interactions: The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.Seeds: The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.