Solanum rostratum

The Long Island case is a classic illustration of many of the factors known to enhance the development of resistance, including intensive commercial production of the insect s principal hosts (potato, tomato, eggplant), a very small number of wild hosts (Solanum rostratum, S. dulcamara) offering only minimal opportunities for avoidance of selection on untreated refugia, and a relatively isolated island location. 

Baggesgaard-Rasmussen H, Boll PM (1962) Soladulcamarine, the alkaloidal glycoside of Solanum dulcamara. Acta Chem Scand 12 802-806 Bah M, Gutidrrez DM, Escobedo C, Mendoza S, Rojas Jl, Rojas A (2004) Methylprotodioscin from the Mexican medical plant Solanum rostratum (Solanaceae). Biochem Syst Ecol 32 197-202... 

As mentioned above, demissine and several other steroid alkaloids are repellent or toxic to the Colorado potato beetle. Races of this insect are adapted to several Solanum species, including S. eleagnifolium, S. rostratum, and 5. tuberosum, and the insect has a recognized ability to adapt to new combinations of steroid alkaloids (Harbome, 1986). 

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