Pests of cotton

The continuing use of pyrethroids in agriculture has led to the emergence of resistant strains of pests. One of the best-studied examples is the tobacco budworm (Heliothis virescens), a very serious pest of cotton in the southern United States (McCaffery... 

The pink bollworm (Pectinophora gossypiella Saund.), considered to be potentially the worst pest of cotton in the United States, occurs throughout the major cotton-producing areas in Mexico, Venezuela, Colombia, Brazil, and Argentina. It probably causes more damage to cotton in the tropical Americas than any other insect. 

Pearson, E. D. "The Insect Pests of Cotton in Tropical Africa" Eastern Press London, 1958 355 pp. 

The boll weevil is a serious pest of cotton bushes, and it produces a sex pheromone known as grandisol. 

Plapp, F.W., Jr., Synergism of pyrethroid insecticides by formamidines against Heliothis pests of cotton, /. Econ. Entomol., 72, 667,1979. 

The three top pests of cotton in Arizona are silverleaf whitefly, Lygus bug, and pink bollworm. In 1992, 1994, and 1995, heavy outbreaks of silverleaf whitefly occurred and contributed considerably to total pesticide applications in those years. Lygus is another pest, for which still old insecticides, such as acephate and endosulfan, are used. The largest plague of pink bollworms occurred in 1979, when on average 6.8 pesticide applications were applied to control this pest. 

ACGIH TLV TWA 0.05 mg/m (skin) Not Classifiable as a Human Carcinogen SAFETY PROFILE Poison by ingesdon, inhaladon, skin contact, subcutaneous, intravenous, and intraperitoneal routes. Mutadon data reported. Used to control the coffee borer and certain economically important pests of cotton. When heated to... 

In the agricultural field, it is used to control many pests, including moth pests of cotton, fruit and vegetable crops. Cypermethrin is a moderately toxic material by thermal absorption or ingestion. It causes irritation to the skin and eyes. If exposed for a long period, it may affect the nervous system. 

A case in point is the unraveling of resistance to methyl parathion in the tobacco budworm, Heliothis virescens, which is a major pest of cotton as well as tobacco. In South Carolina, there is very severe, stable resistance. Although pyrethroid insecticides are very effective and there is no resistance to them in South Carolina at this time, it would be very useful to understand the genetic basis of methyl parathion resistance in case resistance to pyrethroids should arise in the future or spread eastward from Texas where it has been detected. Recent investigations with this pest will be described to illustrate certain mechanisms. 

Strategies for Managing Resistance to Insecticides in Heliothis Pests of Cotton... 

JHE is highly voracious, but is not an abundant enzyme. The development of an efficient affinity purification system (25) permitted isolation of sufficient quantities for generation of antibodies. In addition, partial amino acid sequencing was carried out on JHE from a number of different insect species, most notably from the tobacco budworm, H. virescens, which is a major pest of cotton. A cDNA library derived from the fat body of fifth instar (day 2) larvae of H. virescens was screened, and a clone coding for JHE was identified (26). 

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