Ragweed, Ambrosia

Plantaginaceae, and Compositae. Ragweed (Ambrosia spp.) is the most important single allergenic plant on the North American continent and affects more of our citizens than does smog. Hay fever and similar allergies from weed pollen cause tremendous... 

Five-g samples of wheat plant material were soaked in 150 ml of water for 10 hr at room temperature. The mixture was filtered and the filtrate used to germinate pitted morningglory (Ipomoea lacunosa L.) and ragweed (Ambrosia artemisiifolia L.) seed. The effect of the extract on germination was tested in the presence and absence of light. 

Parallel studies of extracts and mixtures of compounds isolated from ragweed, Ambrosia artemisiifolia L., were also made. Water extracts of ragweed proved highly inhibitory of seed germination. Mixed sesquiterpenes isolated from ragweed were very inhibitory of onion, oat, ryegrass, and Palmer amaranth germination when applied in a dichloromethane solution pretreatment. 

Table VII. Effect of Ragweed (Ambrosia artemisiifolia) Aqueous Leaf Extract on Seed Germination... 

Zelaya, I.A. and M.D.A. Owen (2004). Evolved resistance to acetolactate synthase-inhibiting herbicides in common sunflower (Helianthus annuus), giant ragweed (Ambrosia trifida), and shattercane (Sorghum bicolor) in Iowa. Weed Sci., 52 538-548. 

Giant ragweed Ambrosia trifida (L.) Protomvces aravidus Davis (ascospores) 1 X lO 48 2... 

Persons highly sensitive to ragweed Ambrosia artemisiifolia) may be sensitive to chrysanthemum. 

Ragweed (Ambrosia artemisiifolia L.) contains the complex of chemical substances, including essential oil, glycosides, macroelements, which stimulate seed germination. Unlike other phyto-stirntrlators (nettle, wormwood, etc.), ragweed grows everywhere and is often fotmd as a weed in various crops. 

Mitchell JC, Fritig B, Singh B, Towers GHN (1970) Allergic contact dermatitis from Frullania and Compositae. The role of sesquiterpene lactones. J Invest Dermatol 54 233-239 Mitchell JC, Roy AK, Dupuis G, Towers GHN (1971) Allergic contact dermatitis from ragweeds Ambrosia species). The role of sesquiterpene lactones. Arch Dermatol 104 73-76 O Malley MA, Mathias CG (1988) Distribution of lost-work-time claims for skin disease in California agriculture 1978-1983. Am J Ind Med 14 715-720... 

Sturgeon CM, Craig K, Brown C, Rundle NT, Andersen RJ, Roberge M (2005) Modulation of the G2 cell cycle checkpoint by sesquiterpene lactone psilostachyins A and C isolated from the commom ragweed Ambrosia artemisiifolia. Planta Med 71 938... 

Bagarozzi DA, Pike R, Potempa J, Travis J. Purification and characterization of a novel endopeptidase in ragweed Ambrosia artemisiifolia) pollen. J Biol Chem 1996 271 26227-26232. 

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