Pink bollworm
Encyclopedia
The pink bollworm , is an insect known for being a pest in cotton
farming. The adult is a small, thin, gray moth with fringed wings. The larva is a dull white, eight-legged caterpillar with conspicuous pink banding along its dorsum. The larva reaches one half inch in length.
The pink bollworm is native to Asia, but has become an invasive species
in most of the world's cotton-growing regions. It reached the cotton belt in the southern United States by the 1920s. It is a major pest in the cotton fields of the southern California deserts.
The female moth lays eggs in a cotton boll, and when the larvae emerge from the eggs, they inflict damage through feeding. They chew through the cotton lint to feed on the seeds. Since cotton is used for both fiber
and seed oil
, the damage is twofold. Their disruption of the protective tissue around the boll is a portal of entry for other insects and fungi.
In parts of India, the pink bollworm is now resistant to first generation transgenic Bt cotton
(Bollgard cotton) that expresses a single Bt gene
(Cry1Ac). Monsanto
has admitted that this variety is ineffective against the pink bollworm pest in parts of Gujarat, India
. Infestation on susceptible cotton is generally controlled with insecticides. Once a crop has been harvested, the field is plowed under as soon as possible to stop the life cycle of the new generation of bollworm. Unharvested bolls harbor the larvae, so these are destroyed. The plants are plowed into the earth and the fields are irrigated liberally to drown out remaining pests. Some farmers burn the stubble after harvest. Surviving bollworms will overwinter in the field and reinfest the following season. Populations of bollworms are also controlled with mating disruption
, chemicals and releases of sterile males which mate with the females but fail to fertilize their eggs.
Gossypium
Gossypium is the cotton genus. It belongs to the tribe Gossypieae, in the mallow family, Malvaceae, native to the tropical and subtropical regions from both the Old and New World. The genus Gossypium comprises around 50 species , making it the largest in species number in the tribe Gosssypioieae....
farming. The adult is a small, thin, gray moth with fringed wings. The larva is a dull white, eight-legged caterpillar with conspicuous pink banding along its dorsum. The larva reaches one half inch in length.
The pink bollworm is native to Asia, but has become an invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
in most of the world's cotton-growing regions. It reached the cotton belt in the southern United States by the 1920s. It is a major pest in the cotton fields of the southern California deserts.
The female moth lays eggs in a cotton boll, and when the larvae emerge from the eggs, they inflict damage through feeding. They chew through the cotton lint to feed on the seeds. Since cotton is used for both fiber
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
and seed oil
Cottonseed oil
Cottonseed oil is a cooking oil extracted from the seeds of cotton plant of various species, mainly Gossypium hirsutum and Gossypium herbaceum...
, the damage is twofold. Their disruption of the protective tissue around the boll is a portal of entry for other insects and fungi.
In parts of India, the pink bollworm is now resistant to first generation transgenic Bt cotton
Bacillus thuringiensis
Bacillus thuringiensis is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide; alternatively, the Cry toxin may be extracted and used as a pesticide. B...
(Bollgard cotton) that expresses a single Bt gene
Bacillus thuringiensis
Bacillus thuringiensis is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide; alternatively, the Cry toxin may be extracted and used as a pesticide. B...
(Cry1Ac). Monsanto
Monsanto
The Monsanto Company is a US-based multinational agricultural biotechnology corporation. It is the world's leading producer of the herbicide glyphosate, marketed in the "Roundup" brand of herbicides, and in other brands...
has admitted that this variety is ineffective against the pink bollworm pest in parts of Gujarat, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. Infestation on susceptible cotton is generally controlled with insecticides. Once a crop has been harvested, the field is plowed under as soon as possible to stop the life cycle of the new generation of bollworm. Unharvested bolls harbor the larvae, so these are destroyed. The plants are plowed into the earth and the fields are irrigated liberally to drown out remaining pests. Some farmers burn the stubble after harvest. Surviving bollworms will overwinter in the field and reinfest the following season. Populations of bollworms are also controlled with mating disruption
Mating disruption
Mating disruption is a pest management technique designed to control certain insect infestations. Specifically, mating disruption involves the use of synthesized sex pheromones to disrupt the reproductive cycle of insects.- Mechanism:...
, chemicals and releases of sterile males which mate with the females but fail to fertilize their eggs.
General reference
- New Standard Encyclopedia, © 1990 Chicago, Illinois
External links
- Pink bollworm IPM
- Species Profile- Pink Bollworm (Pectinophora gossypiella), National Invasive Species Information Center, United States National Agricultural LibraryUnited States National Agricultural LibraryThe United States National Agricultural Library is one of the world's largest agricultural research libraries, and serves as a National Library of the United States and as the library of the United States Department of Agriculture...
. Lists general information and resources for Pink Bollworm.