Plants chrysanthemum

Coumarins are pharmacologically active and have been used in the treatment of a diverse range of diseases. The great diversity of coumarin structures and their wide range of polarities present special problems for their simultaneous analysis. The separation of seven closely related coumarins by CZE was studied. Optimized conditions tallied with a 200 mM boric acid—50 mM tetraborate buffer pH 8.5 and were applied to the determination of coumarins in extracts from roots and aerial parts from the plant Chrysanthemum segetum. Baseline separation of six coumarins was achieved in 10 min. 

Susceptible plants Chrysanthemum, cineraria, calendula, lettuce, groundsel, sow-thistle, and other members of the Asteraceae family, indoors and outside. 

Plant-derived insecticides for example, pyrethrum, which is a crude extract from flowers of the pyrethrum plant Chrysanthemum cincerariaefolium. Pyrethrin is a more refined extract containing the six naturally occurring pyrethrins. The greatest activity resides in pyrethrin I. Pyrethrum is regarded as one of the safest insecticides, at least in terms of primary toxicity. It resembles DDT in mode of action, and works at least in part by opening sodium channels in excitable membranes, so causing paralysis. See SODIUM-CHANNEL ACTIVATORS. 

Natural products can occasionally be used for crop protection purposes in their own right. The natural pyrethrins, such as pyrethrin I (Figure 1), are insecticidal compounds produced in the flowers of the plant Chrysanthemum cinerariaefoUum, and are well-known examples. They are used to control insect pests on various crops and on farm and domestic animals, but their use outdoors is limited by their poor stability in sunlight. Incidentally, this example is highly appropriate for this conference held at the University of Nairobi, because much of the world s supply of pyrethrins is produced in Kenya. 

Pyrethrms are a group of naturally occurring insecticidal substances found in the flowers of vanous plants of the chrysanthemum family The following is the structure of a typical pyrethnn cmerin I (exclusive of stereochemistry)... 

Sodium selenate has been used on a small scale in commercial greenhouses, primarily for growing carnations and chrysanthemums. It is transformed by the plants into volatile selenides, which repel red spiders, mites, thrips, and aphids (see Insect control technology). Sodium selenite is not intended for crops which could ultimately be used as food for humans or domestic animals. 

Ohmiya, A. et ah. Carotenoid cleavage dioxygenase (CmCCD4a) contributes to white color formation in Chrysanthemum petals. Plant Physiol. 142, 1193, 2006. 

After mothproofing wool, the next logical step for Geigy was to invent an insecticide that killed more kinds of pests. Imported natural insecticides made from plants, including pyrethrum from tropical chrysanthemums, rotenone from a tropical vine, and nicotine from tobacco, could be quite expensive they were also not persistent and were easily destroyed by light and heat. American and European attempts to synthesize their active ingredients had failed. Arsenic compounds remained the only cheap and effective insecticides. 

Chrysanthemum cinerariaefolium (1) is a species of white flower and contains more insecticidal ingredients than other species. This pyrethrum species originated from Dalmatia and has been used for cultivation. On the other hand, the origin of Roseum (2) is Persia and the Caucasus. It has beautiful red flowers but its pyrethrin content is extremely low compared to (1). Known as red-flowered pyrethrum, it is used merely as an ornamental plant. Marshalli (3) originated from Persia and contains pyrethrins in negligible amounts therefore, the pyrethrum referred to in this text is from C. cinerariaefolium (1). 

Ueda H, Matsuda K (2011) VOC-mediated within-plant communications and nonvolatile systemic signals upregulate pyrethrin biosynthesis in wounded seedlings of Chrysanthemum cinerariaefolium. J Plant Interact 6 89-91... 

Kikuta Y, Ueda H, Nakayama K et al (2011) Specific regulation of pyrethrin biosynthesis in Chrysanthemum cinerariaefolium by a blend of volatiles emitted from artificially damaged conspecific plants. Plant Cell Physiol 52 588-596... 

Tanacetum parthenium (L.) Schultz Bip. is the official Latin name for the member of the Compositae family which is more commonly referred to as feverfew [6]. The plant had previously been classified as Chrysanthemum parthenium (L.) Bernh., so the latter name is strictly speaking no longer correct. Other old classifications for feverfew are Leucanthemum parthenium (L.) Gren. Godron or Pyrethrum parthenium (L.) Sm. 

Susceptible plants A wide range, including runner bean, black and red currant, apple, chrysanthemum, dahlia, fuchsia, and rose. 

Susceptible plants Dahlia, clematis, chrysanthemum, delphinium, and other flowers. 

The most economically important group of natural plant insecticides are the pyrethrins, a group of six closely related esters extracted from pyrethrum (Chrysanthemum clnerariaefollum) flower heads (Figure 1). Pyrethrum has been used as an insecticide since at least the early 1800 s in Persia and Yugoslavia. By 1828 pyrethrum was being processed for commercial Insect control, and by 1939 imports of pyrethrum into the United States reached a peak of 13.5 million pounds. Use of the natural product declined in the early 1950 s because of the advent of synthetic pyrethroid analogs (for example, allethrins), which were both more stable and more effective in the field. The present worldwide demand for pyrethrum flowers remains in excess of 25,000 tons annually and is satisfied by the estimated 150 million flowers still hand-harvested daily, predominantly in natural stands and cultivated fields in Kenya, Tanzania, and Ecuador (9 ). 

Plants have provided several other important pesticides. The group of insecticides called pyrethrums was harvested and refined from chrysanthemums. The plant nux vomica contains strychnine, which was used to kill rodents. Rotenone, another important insecticide was extracted from the root of Denis eliptica. Plant extracts were useful, but difficult to purify and obtain in quantity. Significant increases in the use of pesticides occurred with advances in synthetic chemistry and our understanding of biology. 

Paul Hermann Muller received a degree in chemistry and worked for the J. R. Geigy Corporation, which later became part of Novartis (McGrayne 2001). Geigy specialized in dyestuffs for woolens. Chemists at the company discovered a chlorinated hydrocarbon compound that protected woolens from clothes moths, but it was a stomach poison. Geigy then searched for other insecticides that killed other pests. Natural insecticides made from plants include pyrethrum from chrysanthemum, rotenone from a tropical... 

Pyrethrins are naturally occurring pesticides derived from chrysanthemum plants. They are active against many insects and mites. Over-the-counter liquid and gel preparations of pyrethrins with piperonyl butoxide are available for the treatment of pediculosis (piperonyl butoxide inhibits the hydrolytic enzymes that metabolize the pyrethrins in the arthropod). A synthetic pyre-throid, permethrin (Elimite), is available by prescription. A lower concentration of permethrin (Nix) is available without prescription. Pyrethrins and permethrin are quite safe. 

Figure 32 Novel mutants induced by ion beams. Top left 1-month-old plants of Arabidopsis wild type (top) and UV-B-resistant mutants (bottom) under high UV-B (11-13 kJ/m /day) condition. Top center and right complex (center) and striped (right) flower-color varieties of chrysanthemum. Bottom left flower of Arabidopsis frll mutant. Bottom center and right new carnation varieties with round petals (center) and Dianthus type petals (right).

Other Plants. As already described in Mutation Spectrum, complex and striped types of flower color have been obtained in chrysanthemum. A higher mutation frequency... 

Pyrethrins and pyrethroids are probably the best known and safest classes of natural or synthetic insecticides, widely used in domestic and agricultural applications (1-7). Pyrethrins are natural insecticides derived from the Chrysanthemum cineraria flowers the plant extract, called pyrethrum, is a mixture of six isomers (pyrethrin I and II, cinerin I and II, jasmolin I and II) which was first used in China in the century AD, during the Chou Dinasty. The world pyrethrum market is worth half a billion US dollars [main producers are East Africa highlands (Kenia, Tanzania and Rwanda) and Australia] however, its availability is subject to cyclical trends, due to rains and relations with farmers, who face high harvest costs also due to the fact that the flowers have to be... 

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