Repellant pests

Natarajan, R., Basak, S. C., Balaban, A. T., Klun, J. A., Schmidt, W. F. Chirality index, molecular overlay and biological activity of diastereoisomeric mosquito repellents. Pest. Manag. Sci. 2005, 61, 1193-1201. 

Repellent Repel pests, including insects (such as mosquitoes) and birds... 

Pesticides are chemicals used to destroy pests, control their activity, or prevent them from causing damage. Some pesticides either attract or repel pests. Chemicals which regulate plant growth or remove foliage may also be classified as pesticides. 

Companion planting—planting two or more types of plants in close proximity—is a popular gardening technique that can reduce pest problems in a variety of ways. Some good companion plants, such as dill, fennel, and Queen Anne s lace, will attract beneficial insects. Other types of companion plants repel pests or confuse and confound insects or disease organisms in search of their preferred host plants. To learn more about how diversity helps reduce pest problems, see Encourage Diversity on page 6. 

In reality, pesticides of botanical origin have been used for centuries to protect crops and stored products and to repel pests from human habitations. Among the most well known are pyrethrum, neem, rotenone, nicotine and plant essential oils, although more than 2,000 plant species have been found to possess insecticidal activity [3-4]. However, while most botanical pesticides are known solely for their insecticidal activity, plant essential oils are also known for their uses as fragrances, flavorings, condiments or spices, and many are also considered to have medicinal uses. Given this widespread use, numerous plant essential oils are already widely available and their chemistry is generally well-understood. 

Repellent Repels pests (avian, insect, mammal)... 

Clark, L. and J. Shivik, 2002. Aerosolized essential oils and individual natural product compounds as brown tree snake repellents. Pest Manage. ScL, 58(8) 175 783. 

Pesticides me chemicals used to desiroy, prevent, or control pestS-Pesiicldec also include (11 chemicals used to attract or repell pests, and 121 chemicals used to regulate plant growth or remove or coat leaves. Pests can be dassitied into six main groups ... 

Mason, J.R., L. Clark T.P. Miller. 1993. Evaluation of a pelleted bait containing methyl anthranilate as a bird repellent. Pest. Sci. 39 299-304. 

Thompson, R.D., C.V. Grant D.J. Elias. 1981. Factors affecting red-winged blackbird response to methiocarb, an avian repellent. Pest. Biochem. Physiol. 15 166-171. 

P. KendaU. Nutrition column—Garlic may repel pests as well as people, 2003. 

Many other compounds are presendy in use a 1993 database search showed 27 active ingredients in 212 products registered by the U.S. EPA for human use as repellents or feeding depressants, including octyl bicycloheptene dicarboxamide (A/-2-ethylhexylbicyclo[2.2.1]-5-hepten-2,3-dicarboxamide), dipropyl isocinchomeronate (2,5-pyridine dicarboxyhc acid, dipropyl ester), dimethyl phthalate, oil of citroneUa, cedarwood oil, pyrethrins, and pine tar oil (2). Repellent—toxicant or biting depressant systems are available which are reasonably comfortable for the user and can protect completely against a number of pests for an extended period of time (2). 

Although no consistently effective chemical repellent has been developed for vertebrate pests, some promising materials have been tested as repellents that are based on predator avoidance, specifically compounds from the secretions of predators. In 1995, synthetic sulfur compounds (two thietanes, a thiolane, and a substituted methyl sulfide, which were originally identified from the anal glands of the stoat, ferret, and red fox) suppressed browsing by the introduced AustraUan bmsh-tail opossum in New Zealand about as well as FEP (83). Suggestions were made that these compounds can be made more effective by the use of bitter compounds in a cocktail. 

Natural Insect Attractants and Repellents, New Tools in Pest Control... 

This is not a complete review of the literature of naturally occurring substances that are being or may be used in pest control. Excellent reviews cover well the older literature of natural insect at-tractants (9, 32, 37, 40, 41, 43, 44, 71) and repellents (7, 17, 22, 25, 54, 63, 64). Only the more important recent developments in this field are discussed here. I hope that this report will stimulate the increased interest and investigation on the part of both chemists and entomologists, working together, that is needed to make the concept a reality. 

Although the boll weevil, a very serious cotton pest in the South, feeds voraciously on cotton squares and bolls in response to an at-tractant or attractants contained therein, these same cotton parts (49) contain also a boll weevil repellent that shows its effect once the at-tractant has volatilized completely. Department of Agriculture scientists are attempting to isolate and identify this repellent, which presumably could be applied to ward off weevil attack. Cotton seedlings painted with an aqueous emulsion of the material effectively repelled 100% of the weevils for 5 hours and only medium damage was evident after 12 hours, whereas control seedlings were completely destroyed after only 2 hours. 

In addition, naturally growing plants resist plant pathogen and Insect attack because resistance develops over time via natural selection (35). Also, most natural and crop plants have, as a part of their basic physical and chemical makeup, a wide array of mechanisms that help them resist pest attack. These Include chemical toxicants, repellents, altered plant nutrients, hairiness, thorns, and diverse combinations of these (35). 

The relative toxicity, especially of the newer compounds, to various pests and species is of practical importance, as are also differences in species tolerance to DDT and other sprays. This is also of direct concern in relation to parasites and predators. There is interest in synergistic action and the effect of spreaders, stickers, and related products. The effect and use of repellents and attractants have received attention. 

Universal waste pesticide Pesticide means any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest, or intended for use as a plant regulator, defoliant, or desiccant. 

Allelopathic compounds act as repellents for herbivorous pests, so the same strategy used in weed control could be effective against pests and pathogens. Only allelopathy is not possible to use the complete control of weeds, pests or diseases it is necessary to combine it with other methods of plant protection. 

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