Meaning and Examples
There are many root words that start with cide. The meaning of this prefix in French (in Latin- cidium) is ‘cutting’ or ‘killing.’ Some of the words starting with cide- are algicde, fungicide, avicide, and ichthyocide, etc.
An algaecide or algicide is a chemical substance/organism that is used for killing algae and preventing its growth. Aphicides are natural or synthetic chemical substances that are toxic to aphids (small sap-sucking insects). Fungicides are biocidal chemical compounds that are used to kill parasitic fungi and their spores. Finally, avicides and ichthyocides are chemical substances that are used to kill birds and fishes respectively. Each of these terms has been discussed below in detail. Read on to know more.
What is an Algicide?
Algae are simple plants that can range from microscopic (microalgae) thallophytes to large seaweeds (macroalgae) such as giant kelp which can grow more than one hundred feet in length. Microalgae include both cyanobacteria (similar to bacteria, and formerly called “blue-green algae”) as well as green, brown and red algae. Red tides, blue-green algae, and cyanobacteria are examples of harmful algal blooms that can have a severe impact on human health, aquatic ecosystems, and the economy as a whole. Algal blooms can be very toxic. An algicide is used to kill algae or control excessive algal growth.
Composition of Algicides
Among the available algaecides, there are the ones that have copper ions as the active ingredient. These algicides contain copper sulfate or a chelated copper ion. Then there are algaecides that contain quaternary ammonium compounds (referred to as “quats”) or polymeric quaternary ammonium compounds (referred to as “poly-quats”) in their molecules. Algaecides include copper sulfate, copper chelates (ethanolamines, ethylene diamines, tri-ethanolamines, triethanolamine + ethylene diamine, and copper citrate/gluconate), endothall (as the mono (N, N-dimethylalkylamine) salt), and formulations containing the active ingredient sodium carbonate peroxyhydrate. Excessive exposure to algicides may cause slight eye or skin irritation.
Types of Algaecide:
Natural Algaecide: It is the simplest, natural, long term solution to keep the water clean. Floating plants, such as lilies and lotus, provide shade and reduce direct sunlight in the pond to control the growth of algae.
Barley straw, in England, is placed in mesh bags and floated in fish ponds or water gardens to help reduce algal growth without harming pond plants and animals. Barley straw has not been approved by the United States Environmental Protection Agency (EPA) for use as a pesticide and its effectiveness as an algaecide in ponds has produced mixed results during university testing in the United States and England.
Synthetic Algaecide: Benzalkonium chloride, bethoxazin, copper sulfate, cybutryne,dichlone, dichlorophen, diuron, endothal, fentin, hydrated lime, methabenzthiazuron, nabam, oxyfluorfen, penta-chlorophenyl laurate, quinoclamine, quinonamid, simazine, terbutryn, Tiodonium are all synthetic algaecides.
What are Aphicides?
Aphicides are natural or synthetic chemical substances that are toxic to aphids. Aphids are small sap-sucking insects belonging to the superfamily Aphidoidea. Aphids are a common pest to gardeners, commercial growers and greenhouses due to their wide species diversity and rapid reproductive cycle. There are some 1,351 species of aphids currently recorded in the US and Canada, of which about 80 species are pests of food crops and ornamental plants. Most get their names from the plants they attack, i.e. the green peach aphid, the cabbage aphid, or the rose aphid.
Yellow sticky traps, ribbon traps all are used as natural aphicide. General predators like ladybugs, assassin bugs, minute pirate bugs, Green lacewing act as effective aphid predators. Neem Oil acts as a growth and feeding inhibitor of aphids. BotaniGard 22WP should be applied to affected crop area to control ongoing aphid issues. It uses Beauveria bassiana to infect aphids, spreading White Muscardine disease throughout the pest populations. It provides longer-term control than chemical sprays. Low risk to beneficial insects. There are few aphid parasites which attack and destroys aphid.
Aphidius colemani are most effective between 70° - 77°F. They require two weeks for development and up to 200-300 aphids are attacked by each female.
Aphelinus abdominalis like temperatures beginning at 68°F. They are very versatile because they parasitize a wide range of aphid species and work effectively in fields and greenhouses.
Aphidius ervi consume larger aphids and prefer temperatures between 65° to 77°F with a relative humidity of 60-80%. They work at higher temperatures but show a decline in activity at temperatures above 86°F.
Aphidoletes aphidimyza controls aphids including the green peach aphid as well as the hemlock woolly adelgid. A. aphidimyza prefers greenhouse and indoor environments with temperatures 60-77° with a relative humidity of 70%.
1,5-Diphenyl-1-pentanone (A) and 1,5-diphenyl-2-pentane-1-one (B) are natural products extracted from Stellera chamaejasme. Laboratory bioassay revealed the two compounds showed strong insecticidal activity against Aphis gossypii.
Previously insecticides such as DDT, parathion-methyl, pyrethroids, organophosphorus and carbamate insecticides. But nowadays the aphids have developed a resistant to these.
What are Fungicides?
Fungicides are biocidal chemical compounds or biological organisms used to kill parasitic fungi or their spores. Fungicide is also called antimycotic. They are generally used to control parasitic fungi that either causes economic damage to crop or ornamental plants or endanger the health of domestic animals or humans. Most agricultural and horticultural fungicides are applied as sprays or dust. Seed fungicides are applied to the seed before germination to prevent any fungal growth. In human and veterinary medicine, pharmaceutical fungicides are commonly applied as topical antifungal creams or are given as oral medications.
Types of Fungicides:
Contact Fungicide- It kills fungi when sprayed on its surface.
Systemic Fungicides or Chemotherapeutants- It is absorbed by the plant first and then shows its effect. On entry into the crop plant, they can move to a certain extent within the crop, usually in the xylem vessels, to the site of infection. These fungicides tend to affect a single biochemical pathway within the pathogen and are called site-specific.
Many systemic fungicides can be applied after the initial infection period before symptoms appear (the latent period); this type of treatment is called curative treatment. When disease symptoms are clearly visible, then an eradicating fungicide is required; these chemicals can eradicate a disease that is already present and then protect the plant for a certain time after application. Persistency, curative and eradicative activity varies between chemicals.
According to the composition, they can again be divided into two types:
Chemical Fungicides- Few examples are Mancozeb, Tricyclazole, Carbendazim, Hexaconazole, Metalaxyl, Benomyl.
Organic Fungicides- Example includes Safin which is derived from natural extracts of Allicin & Calotropin. Blastin is derived from a natural extract of monoterpene, G-terpinene & Alkaloids. Bio-Vitriol is is a fungicide which is based on Organic Copper.
Some of the active ingredients present in fungicide are sulfur, neem oil, rosemary oil, jojoba oil and the bacterium Bacillus subtilis. One of the fungicides which are very dangerous to human health is Vinclozolin. Fungicides are usually used to control bacterial and fungal diseases of fruit, vegetable, nut and field crops. Some of the diseases that are controlled by using fungicides are mildew, leaf spots, blights and apple scab.
What are Avicides?
Avicides are substances (normally, a chemical) which can be used to kill birds when they turn out to be a menace for the economy.
Commonly used avicides include strychnine, DRC-1339 (3-chloro-4-methyl aniline hydrochloride, Starlicide) and CPTH (3-chloro-p-toluidine, the free base of Starlicide), and Avitrol (4-aminopyridine).
Thallium can be administered to birds through inhalation or oral consumption. It is a tasteless poison that can be mixed with their feeds or even dissolved in water. Thallium induces nausea, vomiting and pain before killing them. Antifreeze - another deadly remedy commonly used in killing pigeons.
When overheated, non-stick coatings emit several extremely toxic fumes that will kill birds in minutes. Birds are particularly susceptible to Teflon toxicity due to their hyper-efficient respiratory system. Teflon is found on non-stick cookware, waffle irons, and bread machines.
What are Icthyocides?
Icthyocides are chemical substances used to kill fish. Chemical pesticides such as Cyclomethrin, Copper sulphate, Chlorpyrifos and Lambda-cyhalothrin kill fishes. Unlike natural plant-based fish poison, chemical poison has a stronger and more persistent ecological impact.
Rotenone is a naturally occurring compound derived from the roots of certain tropical and subtropical legume plants used to kill fishes. Rotenone kills by inhibiting cellular respiration in mitochondria, which leads to reduced cellular uptake of oxygen. The application rate for rotenone is 0.1 to 5.0 mg/L for the 5% active ingredient liquid and powder formulations. A 2.5% liquid formulation containing a 2.5% synergist is also available. Concentrations of 1 to 3 mg/L are used to remove most fish populations. Humans should not consume these killed fishes.
Chlorine gives marine invertebrates and fish chemical burns. In fish, chlorine burns the gills. At the same time, if absorbed into the bloodstream it will cause burns throughout the fish.
1. What is Bordeaux Mixture?
Ans: Bordeaux mixture - a liquid composed of hydrated lime, copper sulfate, and water, was one of the earliest fungicides. Bordeaux mixture is still widely used to treat orchard trees. It is used in vineyards, fruit-farms and gardens to prevent infestations of downy mildew, powdery mildew and other fungi. It is sprayed on plants as a preventive treatment; its mode of action is ineffective after a fungus has become established.
2. How can Turfgrass Disease be Controlled?
Ans: Cadmium chloride and cadmium succinate are used to control turfgrass diseases.
3. Do You Think Avicide Chemicals Should be Used to Kill Birds?
Ans: Bird killing is not only inhuman but it also disrupts the ecosystem. When birds are made to feed these chemicals they not only die but when new birds flock to these places the poison remnants are bound to affect them thereby continuing the killing cycle.
4. Why Algaecide is Used?
Ans: As algal blooms grow, they deplete the oxygen in the water and block sunlight from reaching fish and plants. When the algae eventually die off, the microbes which decompose the dead algae use up even more oxygen, which in turn causes more fish to die or leave the area. To prevent this algaecide is used.