Anthoxanthum odoratum

A very common evolutionary route in plant speciation is the evolution of self-fertilizing species from outcrossing progenitors (Stebbins, 1970 Wyatt, 1988). An increase in self-fertility in mine ecotypes was demonstrated for both A. capillaris and Anthoxanthum odoratum by McNeilly and Antonovics (1968), and for Armeria maritima by Lefebvre (1970), though there is no evidence that mine plants in the wild self-fertilize more than normal plants of these species. There are a variety of selective forces leading to the evolution of self-fertility (Jain, 1976), but in this context the most likely cause is the need for reproductive assurance in a marginal habitat. 

The simple coumarin nucleus (Fig 7.3), which is derived by lactone formation of an ortho-hydroxy-czs cinnamic acid, is a common metabolite in higher plants and is often found in glycosidic form. Coumarins are common in Api-aceae, in certain genera of Fabaceae (e.g. Dipteryx odorata, Melilotus officinalis), Poaceae (e.g. Anthoxanthum odoratum) and Rubiaceae (e.g. Galium odoratum). However, proliferation of coumarins to the status of major chemical markers occurs in only a few cases, most notably, but not exclusively, in the Api-aceae (subfamily Apioideae) and in the Rutaceae (Gray and Waterman, 1978 Murray et al., 1982). In these cases, the coumarin nucleus has almost invariably been embellished by the addition of a prenyl unit leading to furocoumarin (Fig 7.3) and pyranocoumarin structures. 

Plantago species (plantain) Anthoxanthum odoratum (sweet vernal grass)... 

Ammi visnaga (toothpick weed) Angelica sinensis (dong qua ) Anisodus tanguticus (zangqie), Anthemis species (chamomile) Anthoxanthum odoratum (sweet vernal grass)... 

Ipecac Cephaelis ipecacuanha Sweet vernal grass Anthoxanthum odoratum... 

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