Toxic plant

However, the most interesting of the Baccharis species is most certainly B. coridifolia. This plant is well-known in Brazil as being one of that country s most toxic plants (49) and is a serious hazard to livestock who graze in pastures populated by B. coridifolia (49). Four separate collections were made of B. coridifolia (48). Three of these collections were "From several miles outside Curitaba and a fourth collection in a pasture near Santa Maria, the site of an earlier collection of 13. coridifolia (47), and several hundred miles away from Curitaba. ThTs latter collection and two of the three former collections contained appreciable quantities of roridins A and E. A third collection from near Curitaba appeared to contain no macrocyclic trichothecenes. From a 20 g sample of one of the collections of B. coridifolia... 

Livestock deaths have generally occurred under conditions in which animals consume large amounts of pods or toxic plants in a brief period of time. Most losses happen when hungry livestock are driven through an area of heavy lupine growth, or are trailed through an area where the grass is covered... 

Botha, C.J., Van der Lugt, J.J., Erasmus, G.L., Kellerman, T.S., Schultz, R.A. and Vleggaar, R. (1998). Krimpsiekte, a paretic condition of small stock poisoned by bufadienolide-containing plants of the Crassulaceae in South Africa, in Garland, T. and Barr, A.C., Eds., Toxic plants and other natural toxicants, CAB International, Wallingford, pp. 407%-12. 

Burrows, G.E. and Tyrl, RJ. (2001). Toxic plants of North America, Iowa State Press, Ames. 

During the 1950 s, when the phytotoxic components of the photochemical-oxidant complex were not known, plants were used extensively as a bioassay of many simulated reaction mixtures to indicate toxicity. - - Plants were also used to help in identifying specific components of photochemical reaction products, such as PAN and its analogues. ... 

Vole cycles are thought to be influenced, at least in part, by the ratio of toxic plants in the food (Freeland, 1974). According to this hypothesis. 

Herbivores possibly regulate the amount eaten from toxic plants and thus avoid ill effects. Cattle cycle between consuming large and small amounts of tall larkspur, D. harbeyi. The principal toxic alkaloid in tall larkspur is methyl-lycaconitine (Pfister etcj/., 1997). 

Effects of nutritional status on consumption of toxic plants... 

Two speculative possibilities relate to olfactory aposematism. The first is whether there are non-toxic plants that smell or taste like toxic ones. In other words, do plants practice Batesian mimicry. Such mimicry is unlikely, as mammalian herbivores constantly sample plants and thereby test for favorable and adverse effects of eating a particular species. Furthermore, given the keen sense of smell of mammals, two plant species would have to exactly smell alike for mimicry to work. Second, do two distasteful or toxic plant species smell or taste alike so that herbivores can more easily classify dangerous plants and avoid them (Mullerian mimicry) (Eisner and Grant, 1981 Lindroth, 1988 Augner and Bernays, 1998). 

The tropane alkaloids (—)-hyoscyamine and (—)-hyoscine are found in the toxic plants deadly nightshade (Atropa belladonna) and thornapple (Datura stramonium) and are widely used in medicine. Hyoscyamine, usually in the form of its racemate atropine, is used to dilate the pupil of the eye, and hyoscine is employed to control motion sickness. Both alkaloids are esters of (—)-tropic acid. 

I wiii argue in this chapter that the very process of hydrolysis is an event under the evolutionary control of the competing interests of plant and insect species, and that "toxic" plant glycosides should be regarded as such only in terms of an inseparable, targeted glycoside-glycosidase system. 

SPECIAL NOTE- No illustrations of the various toxic plants and fungi are provided. Black and white photographs or drawings are generally inadequate or proper identification. Any decent bookstore or ibrary has books on poisonous plants with color illustrations. Use one of these as your guide. 

Piperidine alkaloids such as coniine and (—)-coniceine are very poisonous. They occur in hemlock (Conium maculatum L.), known as a very toxic plant. One of the characteristics of these piperidine alkaloids is smell. Moreover, they are neurotoxins which have acute effects such as chronic toxicity. 

Schultes, R. E., and R. F. Raffauf. The Healing Forest medicinal and toxic plants of the northwest Amazonia. Dioscorides Press, Portland, OR. 1995 432-436. 

This volume of the series Medicinal Plants of the World Chemical Constituents, Modern and Traditional Medicinal Uses contains information on 16 plant species and follows the same format as volumes 1 and 2. Some of the plants discussed in volume 3 may be considered controversial in their classification as medicinal. However, the Paracelsian dictum that sola dosis fecit venenum has been appreciated since ancient times, and throughout the ages many highly toxic materials used for lethal purposes have also found applications in modern medicine. It has been recognized that plants contain substances that are either harmful or toxic. However, it is wrong to think that there are plant toxins that are known or that are likely to have adverse effects on any and every form of life. A common feature of most toxic plants is that they are also known for their curative properties, and although they may provide the cure for an individual s disease at one dose, they may cause the death of the same individual at another. 

Although a toxic plant chemical may not fit either category perfectly, those chemicals discussed below that are tissue specific would generally be considered to show specific resistance. It Is interesting to note that those phytochemicals that are especially toxic to one group of Insects are quite often essential dietary Ingredients or feeding stimulants to other Insects that feed primarily on that plant. 

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