The genus
Lygus includes over 40 species of plant-feeding insects in the family
MiridaeThe large and diverse insect family Miridae contains the plant bugs, leaf bugs, and grass bugs, and may also be known as capsid bugs. It is the largest family of true bugs belonging to the suborder Heteroptera, with over 10,000 known species and new ones constantly being described...
. At one time, nearly 200 species were classified as genus
Lygus, but most of those have since been reclassified into new or existing genera. The term
lygus bug is used for any member of genus
Lygus. The more well-known lygus bugs are those that have
agriculturalAgriculture is the production of food and goods through farming and forestry. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and...
impacts. Some lygus bugs are very serious agricultural pests.
The insects appear as small oval creatures.
The genus
Lygus includes over 40 species of plant-feeding insects in the family
MiridaeThe large and diverse insect family Miridae contains the plant bugs, leaf bugs, and grass bugs, and may also be known as capsid bugs. It is the largest family of true bugs belonging to the suborder Heteroptera, with over 10,000 known species and new ones constantly being described...
. At one time, nearly 200 species were classified as genus
Lygus, but most of those have since been reclassified into new or existing genera. The term
lygus bug is used for any member of genus
Lygus. The more well-known lygus bugs are those that have
agriculturalAgriculture is the production of food and goods through farming and forestry. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and...
impacts. Some lygus bugs are very serious agricultural pests.
The insects appear as small oval creatures. Adult lygus are approximately 3 mm wide and 6 mm long, colored anything in a range from pale green to reddish brown or black. The bugs can be solid shaded or mottled, and have a distinctive triangle or V-shape on their backs. Adults are capable of
flightFlight is the process by which an object moves either through the air, or movement beyond earth's atmosphere , by aerodynamically generating lift, propulsive thrust or aerostatically using buoyancy, or by simple ballistic movement.-Buoyant flight:Humans, although not apparently other animals, have...
, and will often thus escape when approached.
NymphA nymph in Greek mythology is a female spirit typically associated with a particular location or landform. Other nymphs, always in the shape of young nubile maidens, were part of the retinue of a god, such as Dionysus, Hermes, or Pan, or a goddess, generally Artemis. Nymphs were the frequent target...
s are wingless, and being light green in color, are often mistaken for
aphidAphids, also known as plant lice , are small plant-eating insects, and members of the superfamily Aphidoidea. Aphids are among the most destructive insect pests on cultivated plants in temperate regions...
s. However, lygus nymphs have harder shells, are typically more active, gain spots as they age, and lack aphid abdominal tubes.
Lygus bugs are known for their destructive feeding habits - they puncture plant tissues with their piercing mouthparts, and feed by sucking
sapSap may refer to:* Plant sap, the fluid transported in xylem cells or phloem sieve tube elements of a plant* A simpleton or fool* Sap, another word for a blackjack, an easily concealed club-like weapon...
. Both the physical injury and the plant's own reaction to the bugs' saliva cause damage to the plant. The females insert their eggs directly into the plant tissues using piercing
ovipositorThe ovipositor is an organ used by some animals for oviposition, i.e. the laying of eggs. It consists of a maximum of three pairs of appendages formed to transmit the egg, to prepare a place for it, and to place it properly...
s, and the newly emerged
nymphsIn biology, a nymph is the immature form of some invertebrates, particularly insects, which undergoes in gradual metamorphosis before reaching its adult stage. Unlike a typical larva, a nymph's overall form already resembles that of the adult. In addition, while a nymph moults it never enters a...
are voracious consumers of plant tissue juices. Signs that a plant has been attacked by lygus bugs include discoloration, deformation of shoots and stems, curling of leaves, and lesions on the plant tissues.
- The tarnished plant bug (Lygus lineolaris) feeds on over half of all commercially-grown crop plants, but favors cotton, alfalfa
Alfalfa is a flowering plant in the pea family Fabaceae cultivated as an important forage crop. In the UK, Australia, and New Zealand it is known as lucerne and as lucerne grass in south Asia...
, beanBean is a common name for large plant seeds of several genera of the family Fabaceae used for human food or animal feed....
s, stone fruitsPrunus is a genus of trees and shrubs, which includes the plums, cherries, peaches, apricots and almonds. It is traditionally placed within the rose family Rosaceae as a subfamily, the Prunoideae , but is sometimes placed in its own family, the Prunaceae...
, and coniferThe conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority...
seedlings. This bug can be found across North AmericaNorth America is the northern continent of the Americas, situated in the Earth's northern hemisphere and in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific...
, from northern Canada to southern Mexico.
- The western tarnished plant bug (Lygus hesperus) is a very serious pest of cotton, strawberries
Fragaria is a genus of flowering plants in the rose family, Rosaceae, commonly known as strawberries for their edible fruits. There are more than 20 described species and many hybrids and cultivars. The most common strawberries grown commercially are cultivars of the Garden strawberry...
, and seed crops such as alfalfaAlfalfa is a flowering plant in the pea family Fabaceae cultivated as an important forage crop. In the UK, Australia, and New Zealand it is known as lucerne and as lucerne grass in south Asia...
. In the state of CaliforniaCalifornia is the most populous state in the United States, and the third largest by area. California is the second most populous sub-national entity in the Americas, behind only São Paulo, Brazil...
alone the bug causes US$30 million in damage to cotton plants each year, and at least US$40 million in losses to the state's strawberry industry.
- The European tarnished plant bug (Lygus rugulipennis) is distributed throughout Europe, where it will feed on over 400 types of crop plant from peach trees
The peach is known as a species of Prunus native to China that bears an edible juicy fruit also called a peach. It is a deciduous tree growing to 4–10 m tall, belonging to the subfamily Prunoideae of the family Rosaceae...
to wheatWheat is a worldwide cultivated grass from the Fertile Crescent region of the Near East. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
to lettuceLettuce is a temperate annual or biennial plant of the daisy family Asteraceae. It is most often grown as a leaf vegetable. In many countries, it is typically eaten cold, raw, in salads, sandwiches, hamburgers, tacos, and in many other dishes...
.
Some methods of
biological pest controlBiological control of pests in agriculture is a method of controlling pests that relies on predation, parasitism, herbivory, or other natural mechanisms...
have proved useful against lygus bugs. For example,
waspThe term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their numbers,...
s of the genus
Peristenus are parasitoids of lygus bugs; an adult wasp will inject an egg into a lygus nymph, and once the egg hatches the wasp's larva will consume the nymph from the inside out.
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