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ChemicalAllelopathy Ecology or serves chemical plant ecology defenses Plants make up more than 90 % of the biomass on the continents. Without defenses they would be down towards 0 %. This is the law. ChemicalAllelopathy Ecology or –chemical chemical ecology defenses Plant Î fungi by phytoalexins plant Î bacteria by antibiotica Plant Î animals by phytotoxins plant Î plant by allelochemicals

ALLELOTOXINS TOXINS ALLELOPATHY OTHER PLANTS HERBIVOROUS ANIMALS

PHYTOALEXINS ANTIBIOTICS FUNGI BACTERIA AllelopathyChemical or chemical Ecology ecology plant Î bacteria by antibiotica Î

Plant Î animals by plant toxins

plant Î plant by allelochemicals

Plant Î fungi by phytoalexins Ecological Types of Interaction Î Mutualism The classical view of symbiosis = but no longer so narrow

Symbiosis with birds with bacteria (Rhizobium) ants or insects

Corn symbiosis with US government

Fungi = mycorrhiza other plants Montropa Indian pipe? Humans AllelopathyChemical or chemical Ecology ecology

Plant Î animals by toxins Plant Î fungi by phytoalexins

plant Î plant by allelochemicals plant Î bacteria by antibiotica Plants and Bacteria plant Î bacteria by antibiotica The most effective herbs for bacterial infections are Sage, Peppermint, Thyme, Cayenne, Ginger and Garlic. warming herbs like Thyme and Cayenne have antiseptic properties. Ginger compounds are active against a form of diarrhea which is the leading cause of infant death in developing countries. Zingerone is likely to be the active constituent against enterotoxigenic Escherichia coli heat- labile enterotoxin-induced diarrhea

Eichhornia crassipes, the water hyacinth isaquatic plant native to the Amazon basin, a highly invasive species outside its range. Root exudations kill bacteria – esp. E. coli Î used in water cleaning. The roots of Eichhornia crassipes also absorb pollutants, including lead, mercury, and strontium-90, as well as carcinogenics, in concentrations 10,000 times that in the surrounding water.[16] Water hyacinths are cultivated for waste water treatment. plant Î bacteria by antibiotica

Iris pseudacorus or yellow flag or is a native of Europe. "false Acorus," refers to the similarity to Acorus calamus While it is primarily an aquatic plant, the rhizomes can survive prolonged dry conditions. Yellow iris has been used as a form of water treatment since it has the ability to take up heavy metals through its roots. tolerates submersion, low pH. The plant spread by both rhizome & water- dispersed seed.

Mentha aquatica Water Mint; is a perennial plant in the genus Mentha native throughout Europe. It hybridises with Mentha spicata (Spearmint) to produce Mentha × piperita (Peppermint), a sterile hybrid; Rotts exude bactericidal substances. Dental care with chewing sticks from trees African Muthala: Chewing sticks -- used for oral hygiene for thousands of years in the Middle East, Africa and Asia -- clean teeth and prevent plaque as effectively as toothbrushes. Twigs from the plant Diospyros lycioides, commonly known as "muthala." The scientists isolated six chemical compounds that demonstrated antimicrobial activity. These compounds kill the oral pathogens responsible for periodontal disease. Arabian Miswak: The most common type of chewing stick is the miswak from the Saudi Arabian Arak tree Salvadora persica. It is very effective in plaque removal The teeth and their care Oral hygiene measures existed before recorded history. Excavations found chewsticks, tree twigs, bird feathers, animal bones and porcupine quills. Indian medicine (Ayurveda) used the neem tree to create toothbrushes. The end of a neem twig is chewed until it is soft and splayed, and it is then used to brush the teeth. In the Muslim Renaissance (starting 900AD), miswak, or siwak, a teeth cleaning twig made from the Salvadora persica tree, also known as the arak tree or the peelu tree was recommended by the prophet Muhammad. Europeans rubbing teeth with baking soda (sodium bicarbonate) or chalk (calcium sulfate) The first toothbrush was invented in China in the late 1400s: stiff hairs from a hog's neck attached to a bamboo stick. Napoleon’s horse hair Î

Toothpaste is a paste or gel dentifrice used with a brush to clean the teeth. Toothpaste is supposed to aid in the removal of dental plaque and food from the teeth, aid in the elimination and/or masking of halitosis and deliver active ingredients such as fluoride or xylitol to prevent tooth and gum disease (gingivitis). Starting with powders (3 parts baking soda + 1 part chalk), most modern toothpastes contain toxic substances not to be swallowed. Antibacterial effects of Fragrant Oils As Gattefosse demonstrated already during WWI: Fragrant oils are antibiotica as strong as penicillin – a remedy developed during WW II. Geraniol: effective against Candida yeast Thymol: knocks out Micrococcus flavus Staphylococcus aureus, epidermitis E. coli, Bacillus subtilis Geraniol, thymol & many other ingredients are found in thyme oil etc. Paul Belaiche (1978) Phytotherapie et d’Aromatherapie (3 volumes). Paris Antimicrobial effects of Fragrant Oils Bactericidal components in essential oils: Monoterpenes in oils of Tea tree, Niaouli, Eucalyptus radiata, Ravensare aromatica Phenols in oils of Thyme, Oregano, Mountain savory Fungicidal components in essential oils: Esters in oils of Lavender, Roman chamomile, Geranium, aldehyde from Cinnamon Mucolytic components in essential oils: Ketones in oils of Eucalyptus dives, Rosemary, Lactones in Inula graveolens brochodilatory components in essential oils: Terpenes in oils of Pine, Cypress, Hazelnut , rubbed on chest for relieve

Paul Belaiche (1978) Phytotherapie et d’Aromatherapie (3 volumes). Paris The society of Jesus (Jesuits) No other order of monks has contributed so much to science. It started with Jose d’Acosta, President of the University of Salamanca (Spain) & first scientific reporter about the Spanish colonies & Indians. Quinine is a natural white crystalline alkaloid having antipyretic (fever- reducing), antimalarial, analgesic (painkilling), anti-inflammatroy properties and a bitter taste (tonic water)

The Jesuit Missionaries discovered medically important species like Cinchona, the Jesuit bark that delivered the alkaloid quinine against malaria. Malaria is a mosquito-borne infectious disease of humans and other animals caused by protists of the genus Plasmodium. Phenols in Medicine: carbolic acid 1834 Friedlieb Ferdinand Runge (Berlin) isolated phenol by distillation of coal tar = since it acted on pH indicators like acid Î carbolic acid Î became the most common disinfectant (3-5 % solution) in hospitals . . due to Joseph Lister –pioneer of carbolic sterilization in medicine (preceding sterilization practice by I. Semmelweiss used lime + chlorine) Î 5 % in vegetable oil used to seal of varicose veins Î injection into nerves destroys nerve cells & transmission of pain Î Today injection of 2,6 Di-isopropyl phenol (Propofol) is used as . . . . intravenous anaesthesiac, causing unconsciousness for several min

Ignaz Semmelweiss Joseph Lister Dronsfield AT & Ellis PM: Education in chemistry 44: 21-22 ( 2007) The history of Antibacterials Infectious Bacteria arebacteria parasites.[1] just like their bigger colleagues like lice and flees, tube worms, protozoa Infectious diseases like TB killed 235,000 US Americans in 1935 78,000 US Americans in 1965 1910 Paul Ehrlich synthesized the first successful man-made drug salvarsan, or 606 to fight syphilis after mercury etc

Infections during WW I showed that sulfonamides could destroy bacteria. In 1935 Gerhard Domagk from IG Farben showed that the red dye prontosil could kill streptococcus bacteria (children). It was shown later that the prontosil was metabolized to sulfanilamides – a new brand of antibiotica. 1929 Alexander Fleming: discovered that Penicillium mold produces a substance that kills a broad spectrum of bacteria. 1938 Australian H. W. Florey and German emigrant Ernst Chain isolated & purified the drug. By 1940 they grew 300 flasks – enough for one patient for one day. 943 a mold on cantaloupes was recognized as esp. productive & US companies grew the mold in large vats. 1944 Selman A. Waksman (Rutgers) Coined term “ antibiotic” tested soil bacteria & found Streptomyces making antibiotic streptomycin tetracycline Bacteria and plants : crown gall disease

Phlobaphenes are found in red corn varieties, hawthorn berries, Geranium leaves Plant symbiosis with bacteria- root nodules Root nodules occur during the interaction of rhizobium bacteria on the with roots of plants (primarily Fabaceae) producing in the process a Symbiosisstructure able with to birds fix nitrogen with from bacteria air in (Rhizobium) the soil (pioneer ants species!)or insects. Legumes release special flavonoids (apigenin, luteolin) from their roots, which (1) attract the rhizobia & trigger the production of nod factors by the bacteria. The nod factor causes : (3) cell division in the root to create the nodule, and (4) alters root hair growth to wind around the bacteria until it encapsulates them

(5) From this microcolony, the bacteria enter the nodule through an infection thread, which grows into the basal part of the epidermis cell, and into the root cortex; they are then surrounded by a special oxygen-tight membrane & form bacteroids that fix nitrogen Plants and Plants AllelopathyAllelopathy – or interplant chemical ecologyhostility

Hans Molisch 1937 Magnificent Austrian Botanist “ Der Einfluss einer Pflanze auf die andere” – Allelopathy. = Adverse effects of one plant on the other. Allelopathy

How do we determine the presence of an allelopathy (0 -) as a phenomenon different from trophic competition (- -)? 1. Use suitable controls (other species, charcoal to absorb root exudation, air filters to remove terpenes, supplemental minerals to ease up competition) 2. Isolate, characterize and assay allelochemicals 3. Produce symptoms by adding chemicals to soil 4. If > 1 substance, test for additive vs. synergistic effects

Ref. Putnam AR, Tang Ch S (1986) The science of allelopathy. Willey & Sons NY AllelopathyChemical or chemical Ecology ecology Bracken fern Pteridium aquilinum Îunknown substance prevents germination of seeds of conifers & higher plants

Broom sedge Andropogon virginicus stops shrub invasion of meadows Î substance unknown

Crucifers or Brassicaceae have glucosinolates that release isothiocyantes or mustard oils with a strong inhibitory effect on lettuce, pigweed Amaranthus

Quassinoids bitter compounds like ailanthone in tree of heaven Ailanthus altissima inhibits cress, grass …

Alkaloids like coffeine are potential herbicides Artemisia tridentata Sage brush releases Volatile Monoterpenes like geraniol inhibits germination of amaranth, ryegrass, crabgrass but not herbal plants

Umbelliferone or 7 –hydroxycoumarin in the Apiaceae inhibits growth of amaranth, millet, velvet leaf Garlic mustard (Alliaria petiolata) - an allelopathic plant Garlic mustard (Alliaria petiolata) is a biennial flowering plant in the Mustard family, Brassicaceae native to Europe but a invasive weed (neophyte) in NAm including Washington.

Absence of native enemies increases its seed production and allows it to out-compete native plants. It is a p threat to the West Virginia White Butterfly (Pieris virginiensis) and Mustard White Butterfly (Pieris oleracea); which lay their eggs on native Dentaria or Toothwort plants, but confuse them with garlic mustard plants. The eggs & young butterflies cannot live on the garlic mustard, because of toxic chemicals

A study published in 2006 concluded that Garlic Mustard produces allelochemicals that harm mycorrhizas that many North American plants, including native forest trees, require for optimum growth.[ Plants with toxic exudations Quackgrass Agropyrum repen or Elytrigia repens (couch grass; is a very common perennial species of grass. Sick dogs are known to dig up and eat the root, mediaeval herbalists used it to treat inflamed bladders, painful urination. It has antiseptic properties.

Johnson grass Sorghum halepense, is a plant in the grass family, Poaceae, native to the MediterraneanFoliage that becomes wilted from frost or hot dry weather can contain enough hydrogen cyanide to kill cattle & horses. Salvia & Artemisia species have terpene emission that stop germination of herbs and grasses, the eternal fight in the grasslands Plants with other root exudations

White mustard (Sinapis alba) is an annual plant of the family Brassicaceae. It is sometimes also referred to as Brassica alba or B. hirta. Grown for its seeds, mustard, as fodder crop or as a green manure, it is now widespread worldwide, although it probably originated in the Mediterranean region. Root exudates include citrate and all acids are anti-bacterials

Parthenium argentatum, commonly known as the Guayule, is a flowering desert shrub in the Asteraceae native to northern Mexico. Because the guayule plant produces terpene resins, which are natural pesticides, it is resistant to many pests and diseases. Herbicides are primarily necessary for stand establishment; the roots exude Î cinnamonic acid is both antibacterial & herbicide Physical (water depr.) vs Chemical competition (allelop.)

Competition has many forms. It is especially fierce in deserts. Both “fair competition for the same resource “water or “hostile” = interference competition by allelopathic chemicals released into the soil. The Petri-dish test screening for presence of allelopathy Molisch’s experiment establishing existence of allelopathy Amygdalin – a potent allelotoxin of peaches & almonds

Phlobaphenes are found in red corn varieties, hawthorn berries, Geranium leaves The walnut tree Juglans regia (Eur) nigra (Nam) … contains a black-staining substance in the hulls of the nuts Î the . . precursor of juglone: 4-glucoside of trihydroxynaphtalene (safe) Juglone = naphtoquinone = a water-soluble, yellow quinone pigment & its reactivity causes or hands to stain brown, our textiles to stain black

plants like tomato, alfalfa, potato die when juglone is injected in petiole 0.002 % juglone prevents germination of lettuce seeds, only Rubus fructosus & Poa pratense are able to live under walnut trees Harborne JB (1988) Introduction to Ecological Biochemistry, Academic Press London Allelopathy of the air –volatile terpenes against grasses Californian chaparral has shrubs Salvia leucophylla & Artemisia tridentata that create bare circles of soil with a diameter of 1-2 m, beyond there are some herbs and then start grasslands with Avena, Bromus, Festuca species The substances that are released a volatile terpenes that compose a cloud around the plants and accumulate in dry soil around the roots. The terpenes are in Salvia l. sagebrush: 1,8-cineole and camphor . in Artemisia tr sagebrush: same + pinene + camphene, No-man’s land made by allelopathic plants – Ambrosia artemisifolia – infamous ragweed Desert plants Parthenium & Encelia – ideal for soil chemicals 1942 Frits Went (auxin discoverer)started research on allelopathic acts of desert plants like composite shrub Encelia on germination of annuals in Mohave desert of CA 1948: 3-acetyl-6-methoxybenzaldehyde is released into ground until removed by next heavy rainfall (rare) inhibits annuals but not same species. The rubber plant guayule Parthenium argentatum – a composite shrub - uses the simplest phenol possible to achieve the same effect: E-cinnamic acid. Inhibits germination of annuals but also seeds of its own species

Harborne JB (1988) Introduction to Ecological Biochemistry, Academic Press London Isolation of “Bioactive Phytochemicals”

Bidlack WR et al (eds.) Phytochemicals as bioactive agents, Technomic Basel Plants and Fungi Plant symbiosis with fungi- Mycorrhizas 1. Mycorrhizal associations; where the fungus colonizes the host plant either going inside the cells as in Arbuscular mycorrhizal Symbiosisfungi (AMF) with or birdsstaying outside with bacteria as in ectomycorrhizal (Rhizobium) antsfungi or (EMF) insects

Ectomycorhizas form around the roots of woody plants like birch, eucalyptus, oak, pine, & rose. The fungi are basiomycetes. EMs occur only 10 % of all plant families

Ericaceae or heathers (cranberry, erica, cassiope, huckleberry, azalea, rhodoendron, wintergreen etc.) have special saprotrophic m. which provide nutrient from decomposing biomaterials Only Brassicaceae (mustards & cabbages have strongly antifungal mustard oils or isothiocyanates) + Chenopodiaceae (beets, spinach, chard) have no mycor. Plant symbiosis with fungi- ectomycorrhizas Ectomycorhizas form around the roots of woody plants like birch, eucalyptus, oak, pine, & rose. The fungi are basiomycetes or ascomycete Plant symbiosis with fungi- endomycorrhizas Endomycorhizas are the most common form of mutualistic relation between fungi and plants. However, most fungi are decomposers & plants that do not want to be decomposed ….. better do something about it. The most anti-fungal plants are the Brassicaceae, which do not even tolerate mycorrhizal fungi.

Upon contact between fungal probes and plant cell walls the two start mutual digestion Î Parts of fungal walls alert the “Phytoimmune Close-up at the surface between .. system” of plants and it jumps into action. plants can acquire resistance to potato blight Phytoalexins were discovered 1940 in Germany by Muller and Borger. The infected potatoes with an incompatible (harmless) race of Phytophtora (yes, that is the culprit for the potato blight, that caused the Irish potato famine). If later treated with the tuber-infecting(compatible) race the tubers had acquired resitance in the form of low-molecular-weight terpenoid compounds – a phyotalexin of potatoes called rishitin.

Later such substances were found in other plants like beans: Phaseollin, kievitone and glyceollin. The question was & Phytophtora-infested potato is, whether phytoalexins are just the end products of a pathogen- disturbed metabolism or an intended defense measure.

M¨uller KO, Borger H. 1940. Experimentelle Untersuchungen ¨uber die Phytophthora infestans-Resistenz der Kartoffel. Arb. Biol. Reichsanst. Land Forstwirtsch. 23:189–31 Plants Î fungi by phytoalexins Phytoalexins are synthesized de novo and accumulate rapidly upon pathogen infection. They act as toxins against the pathogen.. They are chemically diverse including terpenoids, glycosteroids and alkaloids Induction: When a plant cell recognizes particles from damaged sister cells or particles from the pathogen, : Î plants often launch a two-step defense (1)a general short-term response where it deploys reactive oxygen species such as superoxide and hydrogen peroxide to kill invading cells & sometimes apoptosis, or programmed cell death (2) a long-term specific response (SIR or systemic induced resistance), like production of tannins, alkaloids or specific antidotes like phytoalexins

Phytoalexin induction is a common feature with that of antibodies Î hence sometimes called phytoimmune system Plants Î fungi by phytoalexins

Garlic Allium sativum produces phytoalexin allixin, a non-sulfur- containing compound & the first compound isolated from garlicunder continuous stress.[2] This compound has been shown to have unique biological properties, such as anti-oxidative effects,[2] anti-microbial Monomer and dimer of allixin effects,[2] anti-tumor promoting effects,[3] inhibition of aflatoxin B2 DNA binding,[4]and neurotrophic effects.[4Allixin is expected useful compounds for cancer prevention or chemotherapy.

Allixin is a phytoallexin found in garlic (Allium sativum) bulbs in 1989. When garlic is stored for long time, it forms visible accumulations of crystalline allixin on its surface, particularly where tissue is necrotic Plants Î fungi by phytoalexins

Brassica or crucifer species are known to produce the glucoside glucobrassicin under continuous stress. When cabbage cells are destroyed GB release isothiocyanates or mustard oils which are volatile & antifungal.

In addition Brassicas also produce more specific antifungal Monomer and dimer of allixin compounds like brassinin, brassilaexin & sinalexin, cyclobrassinin Plants Î fungi by phytoalexins

sorghum leaf inoculated 24 hours previously with C. sublineolum. Colourless inclusions accumulate in the cytoplasm of cells beneath fungal appressoria.

By 36 hours after inoculation, the inclusion have started to coalesce and are intensely red pigmented.

By 42 hours after inoculation, the inclusions have released their contents into the cell and pigmented inclusions are starting to accumulate in surrounding cells. Sorghum is a genus of numerous species of grasses for grain and fodder Plants and Insects Myrmecochory or mutualism with ants The distribution of plant seeds through ants is one of the amazing examples of co-evolution & intelligent behavior of plants. Ant propagated seeds are characterized by seeds with appendages in the form of fatbodies = elaiosomes. These are found in clelandine Chelidonium, the lablab beans, in larkspur Corydalis, in Ranunculus ficaria, Viola odorata, the Lamium maculatum, Melampyrum bloodroot, woods poppy , Trillium, Erythronium, Casor bean, Datura, Dicentra and tropical plants.

Tasks: 1. Take a closer look (microscope) at the seeds provided today. 2. you should do this one on your own. Visit an anthill & drop pH paper on it &also some seeds having elaiosomes. You will have 30 min of entertainment. Insects mimicking Plant Seeds We know that passion flowers mimic the deposition of eggs on their leaves in order to deter the pregnant butterfly to deposit her eggs next to their cannibalistic cousins. Stick insect But there are insects who mimic plant seeds, in particular the Stick Insect – a slow moving leaf eater mimicking a branch. Unlike most soft insect eggs, these have a shell hardened by Ca salts and take a brown, shiny appearance of a seed. More important is appearance of a capitulum rich in fats & resembling seed elaiosomes, that bloodroot are detached by foraging ants without damage to the egg.

The ants transport the eggs like seeds to their nests, detach the fat bodies to feed their larvae and deposit the rest on their junk pile an ideal breeding ground for plant seeds and a protected place from predating wasps and plant eaters A famous plant in S Africa depends on ant propagation: red stump or Mimetes cucullatus. Introduced Argentine ants do not transport the seeds & where they rule, the plants rapidly disappear Ant Gardens Ants pick up seeds with elaiosomes since the release of oleic acid (dead ant signal) triggers this. The addition of linoleic acid and 1,2 diolein, however, signals the ants that this is precious food for their offspring and lets them carry it all the way to the the nest. Some tropical arboreal ants collect plant seeds for a different reason. They carry the seeds into their nests high in the tree. There the plants become a structural part of the nest called an ant garden. The ants chose seeds with MMS (methyl 6-methyl salicylate).containThe seeds anti-fungal may also compounds. But the most aggressive ant species in the world, exceeding may be Camponotus femoratus, a large, hairy and decidedly unpleasant ant of South American rain forests. When disturbed in the slightest, the workers boil out in an angry mass over the nest http://www.primitivism.com/ant-gardens.htmsurface. Scents as Life’s Elixir? The bee’s way to extract essential oils We know that the fragrance of flowers is a signal to guide insect & bat pollinators to the flowers where they are rewarded by food donations in the form of either pollen or nectar However, some plants do not offer food, e.g. orchids. They offer either illusion of sex (bee orchid), violence (hammer orchid) or a selection of fine fragrance (bee o) Euglossine bees are the pollinators of bee orchids, which reward them with scents generated by glands in the orchid flowers producing about 60 various scents. The male bees exude some lipid solvent to their front feet & mop the scents up to finally collect them in slit- opening bags of the hind feet. Bees show intoxication & falls into a bucket that leads to the anther where a pollen packet (pollinarium) is glued to its head; funny looks Î This orchid fragrance Î extends the life span of the male euglossine bees! Plants produce specific insect poisons, hormones and sexual attractants

Mutualism (+ +) or Commesalism (+ 0) ??? Herbivores ... Help ...Herbivores

These are only the zoological antagonists of plants. You add to this representatives of the bacteria, fungi & other plants. Plants and Insects The majority of animals is herbivorous = feeds on plants! Spines, thorns, cuticle, camouflage, repelling smell, taste & deadly toxins are the reason that plants keep dominating (95 %!) the planet’s biomass Herbivores feed only on one to a few plant species because they can only overcome a few of the defense mechanisms. Even humans (only herbi species that cooks & selects population featuresby breeding) feed only on very small number of plants out of the 400 000 species on the planet. E.g. we feed only on the petioles of rhubarb leaves & discard the oxalate-rich blades. H Milky caustic, toxic juice flows through many plants with lactifers (pressurized vessels running in parallel with water- transporting xylem & sugar- transporting phloem). Occurring in Apocynaeceae, Euphorbiaecea, Asteraecea, Caricaceae, Moracea Can Plants produce a Polymer muzzle for Insects? 1905 H Kniep carried out classical experiment on chemical defense in plants. By repeated poking the midvein of Euphorbias he drained/milked them & found them now being eaten by snails. Kniep did not know that some insects have practiced his method regularly to avoid being poisoned or muzzled alive!

Drain the lactifer defense chemicals or get muzzled !!!

R: Thomas Eisner “ For love of insects” Harvard University Press, 2003 Natural Plant Insecticides - Repellents Plants produce many powerful insecticides like nicotine (Nicotiana plants), plant sterols (drug precursors), urushiol (poison oak and ivy oil), as well as pyrethrum, chrysanthemic acid and rotenone (insecticides) and neem oil. In addition plants produce essential oils are peppermint oil, clove oil, citrus oils, lavender oil, thyme oil, and rosemary oil as insect repellents essential oils that work well against biting insects: cinnamon oil (mosquitoes) castor oil (mosquitoes) eucalyptus oil (mosquitoes, ticks, and lice) citronella oil (mosquitoes and biting flies) orange oil (fleas) rose geranium (ticks and lice) Safe carrier oils and alcohols include: olive oil, sunflower oil, other cooking oil, witch hazel, vodka good rule of thumb is to mix the repellent so it's 5-10% essential oil, so mix 1 part essential oil with 10-20 parts carrier oil Natural Plant Insecticides - Pyrethrum Pyrethrum refers to several Old World plants of the genus Chrysanthemum which are cultivated as ornamentals for their showy flower heads. It is also the name of a natural insecticide made from the dried flower heads of C. cinerariifolium and C. coccineum. Pyrethrum was used for centuries as an insecticide & as a lice remedy ("Persian Insect Powder," "Persian Pellitory"). The flowers are pulverized and pyrethrins, contained in the seed cases, are extracted and sold in the form of an oleoresin. This is applied as a suspension in water or oil, or as a powder. Pyrethrins attack the nervous systems of all insects, and inhibit female mosquitoes from biting. Pyrethroids are synthetic chemicals similar to the natural chemical pyrethrins produced by the flowers of pyrethrums (Chrysanthemum cinerariaefolium and C. coccineum). They are a major part of the insecticide market and common in household insecticides. Pyrethroids are able to pass through secondary treatment systems at wastewater treatment facilities in levels lethal to invertebrates. Insecticides from the Neem tree = Indian lilac Neem tree Azadirachta indica inhibits development of insect larvae but is harmless to mammals (us), bees and ladybugs. The chemical compound responsible for Neem action is azadirachtin = an unusual tetra-terpenopid

Neem (Azadirachta indica) is an evergreen tree in the mahogany family Meliaceae. It is one of two species in the genus Azadirachta, and is native to Indian subcontinebt plus East Africa: Mwarobaini (Swahili), which means the tree of the 40; it's said to treat 40 different diseases. Natural Plant Insecticides – Neem oil Neem oil is pressed from the fruits and seeds of neem (Azadirachta indica), an evergreen tree from India. Used for org farming & medicine Neem oil is brown, bitter with strong odour that combines peanut and garlic. It consists of triglycerides and large amounts of triterpenoids, which give it the bitter taste. Azadirachtin is the most well known and studied triterpenoid. Another triterpenoid isolated from neem is salannin -a powerfull insect repellent, Active as feeding inhibitor against the desert locust (Schistocerca), it is now known to affect > 200 species of insect, by acting mainly as an antifeedant and growth disruptor, with high toxicity toward insects (LD50(S. littoralis): 15 ug/g). Azadirachtin is biodegradable (it degrades within 100 hours when exposed to light and water) & has very low toxicity to mammals (the LD50 in rats is > 3,540 mg/kg = non-toxic). Azadirachtin is structurally similar to insect hormones called "ecdysones," which control the process of metamorphosis as the insects pass from larva to pupa to adult. It blocking production &controlled release of hormones. “Eat me and your seed will disappear from this world!” Phytoecdysons are plant substances that simulate ecdysons, hormones that control the insect metamorphosis from larva, pupa to adult = Phytoecdysteroids. Therefore these substances are the equivalent of phytoestrogens in mammals. These compounds are exact replicas of hormones used by the arthropod (insect) and crustacean (crab/lobster) families in the molting process known as ecdysis.Aside from citrus fruits and neem tree it is assumed that many more plants have the ability to "turn on" the production of phytoecdysteroids when under constant herbivore pressure.

Similar substances are also used by cordyceps a fungus that grows out of the larvae of several insect species.

Azadirachtin is structurally similar to insect hormones called "ecdysones," Natural Plant Insecticides – Rotenone Rotenone is an odorless flavone molecule that is used as a broad- spectrum insecticide, piscicide, and pesticide. It occurs naturally in the roots and stems of several plants such as: Florida fishpoison tree (Piscidia piscipula) – southern Florida, Jicama vine plant (Tephrosia virginiana) – North America Cubé Plant or Lancepod (Lonchocarpus utilis) – South America Jewel Vine (Derris involuta) – SE Asia & SW Pacific islands the Rotenone is badly taken up by skin and human guts but well by gills of fishes Î fish poison, used by Amazonians to fish & today to stop invasion of invading fish species in access streams. It interferes with the electron transport chain in mitochondria. Rotenone is the most effective tool available because it has only minor and transient environmental side-effects. Wound-induced airborne volatiles as SOS signals: insect regurgitant volicitin (amine) triggers synthesis of volatile terpenoids as wasp attractants in maize through methyl jasmonate in cotton

Through terpenoid trans-2- hexenal in Phaseolus Herbivores ... Help ... Biiig Herbivores ….

These are only the zoological antagonists of plants. You add to this representatives of the bacteria, fungi & other plants. Arrow Poisons Curare: Alkaloid d-turbocurarin from vine Chondrodendrum tomentosum is a fast acting muscle relaxant. It has to enter the blood stream , so meat is safe to eat if your gut is ok. The prey is not dead but paralyzed & experiences the whole scene with P13 terror. Victims die after hours when curarin reaches the lungs (artificial respiration keeps them alive). It does not relive the pain but prevents patients from thrashing around. Strychnine: from tree Strychnos nux-vomica acts similar but acts faster Kombe: from the African vine Strophantus kombe contains a cardiac glycoside that slows the pulse in low doses. Polluted area of meat must be discarded. Arrow plant Acokantherea is an SAfrican shrub with juice that contains cardiac glycoside . Was smeared on arrows and weapons and on fruits of punture vine as as poisonous land mine.

Upas tree: Antiaris in the mulberry tree family is an Asian tree with brk and leaves filled with a toxic sap. Was suspected to exude deadly fumes to people close to him, but no volatile toxins were found. Juice was used as aroow poison and also in flaming fire lances thrown by the Chinese army.