"Blinding" of shoots and a leaf gall in Amsinckia intermedia induced by Anguina amsinckia (Steiner and Scott, 1934) (Nemata, Tylenchidae), with a note on the absence of a rachis in A. amsinckia.

Morphometric Analysis of Anguina amsinckiae from Three Host Species.

Amsinckia species (fiddleneck) in the South Coast Ranges of California were surveyed to determine if any of the 12 different California species of Amsinckia are hosts of the nematode, Anguina amsinckiae (Steiner and Scott, 1935) Thorne, 1961. Previously only Amsinckia intermedia Fischer and Meyer was reported as a host of Anguina amsinckiae. The survey established that there are at least two ad...

Profiling of Dehydropyrrolizidine Alkaloids and their N-Oxides in Herbarium-Preserved Specimens of Amsinckia Species Using HPLC-esi(+)MS

Species of the Amsinckia genus (Boraginaceae) are known to produce potentially hepato-, pneumo-, and/or genotoxic dehydropyrrolizidine alkaloids. However, the taxonomic differentiation of Amsinckia species can be very subtle and there seems to be marked differences in toxicity toward grazing livestock. Methanol extracts of mass-limited leaf samples from herbarium specimens (collected from 1899 ...

Islet cell tumors of the pancreas found in rats given pyrrolizidine alkaloids from Amsinckia intermedia Fisch and Mey and from Heliotropium supinum L.

One adenoma and one adenocarcinoma of the islet cells and one adenoma of the exocrine pancreas were found in 3 out of 15 rats given a single dose (500 to 1500 mg/kg body weight) of pyrrolizidine alkaloids from Amsinckia intermedia Fisch and Mey (Boraginaceae), tarweed, a plant known to cause livestock losses from liver damage in the United States. Among rats treated with Heliotropium supinum L....

Frequency-dependent inbreeding depression in Amsinckia.

If the competitive ability of plants produced by self-pollination differs from that of plants derived by outcrossing, then the magnitude of inbreeding depression may be influenced by the composition of the competitive environment (i.e., the frequency of plants that have arisen from selfing and outcrossing in the neighborhood of "target" plants in which inbreeding depression is expressed). Here,...

Pyrrolizidine Alkaloid– Containing Toxic Plants (<i>Senecio, Crotalaria, Cynoglossum, Amsinckia, Heliotropium, </i> and <i>Echium</i> spp.)