Genus Senecio

The pyrrolizidine alkaloids, found in the genus Senecio and a number of other plant genera, are plant toxins of environmental interest that have been implicated in a number... 

Analyses of the cinnibar moth, Tyria jacobaeae, revealed an interesting example for sequestration of defensive terpenoids. As with many other moths found within the family Actiidae, larvae of this species are able to sequester pyrrolizidine alkaloids (also see Section 2.04.6.4) from their plant host, in this case species from the genus Senecio. A population of T. jacobaeae was recendy identified, however, which lives on plants from the genus Petasites, from which it instead sequesters terpenoids such as petasol (26) and related compounds (Figure 9). ... 

Presently, there are over 300 PAs characterized with the highest numbers found in the genus Senecio (Asteraceae family), which contains senecionine with concentrations of up to 18 % of the dry weight of the plant [22], retrorsine [28], integerrimine, neosenkirkine, and florosenine [32]. 

Serious livestock poisoning episodes are mentioned in literature from the effects of the pyrrolizidine alkaloid of the Senecio genus, especially Senecio riddellii, Senecio douglasii, and Senecio jacobaea The toxicity of... 

Swenson, U. and Bremer, K., Pacific biogeography of the Asteraceae genus Abrotanella (Senecio-neae, Blemnospermatinae), Syst. Bot., 22, 493-508, 1998. 

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