Geographic Range
The Russian wheat aphid,
Diuraphis Noxia
, is one of the most invasive agricultural pests found across the globe. It is native
to Asia, originating in southern Russia, Central Asia, and the Middle East. Beginning
in the early 1900’s it began to rapidly spread from its native origin of Asia to other
countries by means of wind aided dispersal. As a result, these aphids are now found
on every continent except Australia and Antarctica. Most recently, the Russian wheat
aphid has invaded Canada and the United States.
- Biogeographic Regions
- nearctic
- palearctic
- oriental
- ethiopian
- neotropical
- Other Geographic Terms
- holarctic
Habitat
Russian wheat aphids are able to survive in a variety of habitats as a result of their
ability to withstand a wide range of temperatures. Unlike other aphids which move
to woody areas throughout the course of the year, the Russian wheat aphids live inside
the rolled leaves of cereal crops and grasses year round. Of these cereal crops, wheat
and barley are the plants most commonly infested by
Diuraphis noxia
. Other cool season grasses such as crested wheat grasses, intermediate wheat grasses,
and wild ryes serve as host plants when the preferred cereal crops are not available.
These cool season grasses are essential for the survival of the Russian wheat aphid
during the warm seasons between wheat harvest and wheat emergence.
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- savanna or grassland
- Other Habitat Features
- agricultural
Physical Description
Russian wheat aphids are green and relatively small, ranging from 1.6 to 2.1 mm long.
The body of the aphids is spindle-shaped, appearing wider in the middle and tapering
on each end. Russian wheat aphids have short antennae and a piercing-sucking stylet
on their head. When the aphid is observed from the posterior end, the sides create
what looks like a double tail. Russian wheat aphids have reduced cone-shaped cornicles
with their wings which appear like shoulder pads.
- Other Physical Features
- ectothermic
- heterothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Development
The Russian wheat aphid life cycle begins inside a parthenogenetic female, where development
takes place without fertilization. These females give birth to live, genetically identical
daughters. Young nymphs appear similar to the adult aphid but covered with a white
waxy filament. The maturation of
Diuraphis noxia
depends on the temperature of their environment. If the temperature in their environment
is below 25 degree Celsius, they mature at a slow rate. Whereas an aphid living in
an environment with a temperature at or above 25 degrees Celsius will grow at a much
faster rate. On average, Russian wheat aphids take nine to 55 days to become a mature
adult aphid. In some populations, sexual reproduction takes place between males and
females just before winter. The female lays eggs that overwinter, and emerge again
in the spring.
- Development - Life Cycle
- metamorphosis
Reproduction
The Russian wheat aphid can reproduce both sexually and asexually. North American
populations consist solely of females, so they do not mate at any point in their lives.
Other non-North American populations mate in the fall, though there is little additional
information available.
The Russian wheat aphid can reproduce sexually and asexually. During asexual reproduction, female aphids do not lay eggs, and instead give birth to live genetically identical daughters over the course of 60 to 80 days. Asexual reproduction causes massive growth within the population. In North American populations, there have been no traces of male aphids. As a result, the female aphids are unable to reproduce sexually and rely solely on asexual reproduction to produce their offspring.
Diuraphis noxia reproduces in high numbers forming colonies that benefits its survival. On average, Russian wheat aphids take 9 to 55 days to reach maturity and start reproducing. Temperature that best suits the reproduction cycle of the aphids ranges from 15 to 21 degrees Celsius. Although Russian wheat aphids can survive in a variety of temperatures, a temperature below 4 degrees Celsius will stop aphid reproduction. On average during temperatures between 15 and 21 degrees Celsius, a mature Russian wheat aphid can produce up to 1.5 daughter nymphs per day over the span of a month. In some cases, females can reproduce up to four nymphs in a single day.
In non-North American populations, sexual reproduction may occur in the fall, where
females mate and then lay eggs that overwinter.
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- asexual
- fertilization
- viviparous
- oviparous
Most
Diuraphis noxia
females give birth to live young, which is likely a significant energy investment
on their part. In some populations, eggs are produced by sexual reproduction, and
these eggs contain provisioning provided by the female parent, allowing for the eggs
to survive through winter. After birth or after the eggs are laid, no further parental
interaction or care is given.
- Parental Investment
-
pre-hatching/birth
-
provisioning
- female
-
provisioning
Lifespan/Longevity
The lifespan of
D. noxia
is about three months. Environmental temperature has a great effect on their lifespan.
Their lifespan decreases when the aphids spend a significant amount of time in temperatures
below 0° C.
Behavior
Diuraphis noxia , like most aphids, lives in large colonies. There are several generations of winged aphids produced each year. Aphids in general are poor fliers and strongly rely on wind to move them from area to area as they search for new host plants. The rest of the aphids are wingless.
The every day behavior of Russian wheat aphids can be sorted into phases, based on
their feeding activity. During the first phase, the aphids find a potential plant
to feed on. This is a random process that is referred as the pre-alighting behavior.
During the second phase, the aphids will begin to examine and explore the plant's
leaves searching for a spot to feed upon. This phase is known as the exploration of
the plant surface and the immediate subepidermal tissues. The third and fourth phase
are joined phases. In these phases the aphids look for the parts of the plant that
are nutritional tissues and begin eating. The aphids feed from the phloem in the leaves.
When an aphid is done taking the nutrients it needs, it moves on to a new potential
plant.
Home Range
Alate Russian wheat aphids fly to plants in new areas to establish new colonies. Since
aphids are poor fliers, it is unlikely that they travel long distances unless on a
particularly strong wind current. Wingless aphids and nymphs are sedentary and remain
in the same general area.
Communication and Perception
Russian wheat aphids communicate with each other by producing an alarm pheromone.
The alarm pheromone is secreted by the cornicles located at the end of the abdomen.
The alarm pheromone helps detect another aphid or a predator near them. If a predator
is near they respond by dropping off the host plant.
- Communication Channels
- chemical
- Other Communication Modes
- pheromones
- Perception Channels
- chemical
Food Habits
Russian wheat aphids feed on phloem from plants, using their stylet mouth parts to pierce the plant material. They tend to be found in small grain fields or grasses year round. They favor mostly wheat and barley and in cold seasons they switch their diet to wheatgrass, intermediate wheatgrass, and Canada wild rye. They start feeding on the top or edge of the plant depleting the plants nutrients. Once the plant loses its nutrients and a colony of large numbers begins to form, the leaf begins to rapidly roll inward, protecting the aphids from dangers including natural enemies and insecticidal sprays.
During the Russian wheat aphid feeding process they release toxins that cause discoloration on the plants they feed on. The toxin released inside the plants causes the plants to become discolored and can appear white, purple, and yellow to the naked eye. When feeding on developing plants they can prevent the head of the plant to open up stunting the plants development. In some cases, the Russian wheat aphid causes the edges of wheat grains to become bleached, halting the grains development.
The food habits of
Diuraphis noxia
are greatly influenced by seasonal changes. During the fall season, they move from
plant leaves to the inside of curled leaves to be protected from cold temperatures.
In warmer seasons, Russian wheat aphids appear on the edges of leaves where they feed.
- Primary Diet
-
herbivore
- eats sap or other plant foods
- Plant Foods
- sap or other plant fluids
Predation
Natural predators of the Russian wheat aphids include the convergent lady beetle (
Hippodamia convergens
), the seven-spotted lady beetle (
Coccinella sepempuncata
), the lady beetle
Hippodamia variegata
, Aphidiid wasps (
Aphidiidae
), hover flies (Diptera: Syrphidae),
Scymnus
beetles, lacewings (
Chrysopidae
), rove beetles (
Staphylinidae
), and spiders (
Araneae
). The Russian wheat aphid hides in the curled leaves of a wheat plant, making it
hard for larger predators to reach them. Convergent lady beetles, seven-spotted lady
beetles and Scymnus beetles are small enough to crawl inside the curled part of the
leaves and feed on the aphids. They also drop off their host plants when a predator
is near, and alert the colony of a predators' presence with an alarm pheromone.
Ecosystem Roles
As one of the most invasive agricultural species in the world, Russian wheat aphids have an extensive impact on the ecosystems they invade. As their habitat range continues to expand into new regions, Russian wheat aphids are continually destroying the plants they feed on, which include a variety of cereal grains, such as wheat and barley. While feeding, the Russian wheat aphid transfers a toxin that causes extreme discoloration. Plants that become heavily infested with the toxin have leaves with identifiable purple, white, or yellow streaks. Heavy feedings from Diuraphis noxia can also prevent normal formation and distortion of grain heads and leaves. In some cases their feeding averts the proper unrolling of leaves and causes the formation of bleached heads with poorly shaped grains. As a result, grain production and quality is drastically reduced.
Like all aphid species, Diuraphis noxia has an endosymbiotic bacterium, Buchnera spp. This is an obligate relationship for both organisms, as Buchnera can survive outside of bodies of aphids. In return, Buchnera produces essential amino acids that Russian wheat aphids need to survive and do not get from their plant phloem diet.
Russian wheat aphids are also parasitized by many parasitoid wasp species. The wasps
lay an egg inside of the aphid's body, which cause the eventually mummification and
death of the aphid. These wasps are often used as natural biocontrol methods to prevent
infestations of
Diuraphis noxia
. Parasitoid wasps species for Russian wheat aphids include
Aphidius
species such as
Aphidius colemani
,
braconid
wasps,
Aphelinus albipodus
, and
Lysiphlebus testaceipes
.
- wheat, Triticum spp.
- barley, Hordeum vulgare
- wheatgrass, Triticum aestivum
- intermediate wheatgrass, Thinopyrum intermedium
- Canada wild rye, Elymus canadensis
- bacteria, Buchnera
- wasp, Aphidius spp.
- wasp, Aphidius colemani
- braconid wasps, Braconidae
- wasp, Aphelinus albipodus
- Aphidiid wasp, Lysiphlebus testaceipes
Economic Importance for Humans: Positive
There are no known positive effects of Diuraphis noxia on humans.
Economic Importance for Humans: Negative
In the United States, the Russian wheat aphid has caused many significant economic
losses. Since their discovery in Texas in March 1986, the United States has lost millions
of dollars in wheat and barley production. In addition to the depletion of cereal
crops, millions of dollars have been spent on pesticide treatments in attempts to
quarantine the species. In 1988, the annual yield losses peaked at $274 million dollars
but in later years dropped to $10 million. While in recent years the appearance of
the Russian wheat aphid has decreased, the species still appears occasionally across
the High Plains in Nebraska, Wyoming, Colorado, Kansas, and New Mexico.
- Negative Impacts
- crop pest
Conservation Status
As an invasive species,
Diuraphis noxia
has no special conservation status. Instead, Russian wheat aphids are considered
to be one of the most invasive pests of small grains in the world, and there are many
efforts to control their populations.
Additional Links
Contributors
Najma Salah (author), Grand View University, Kassie Sopher (author), Grand View University, Ashley Sowder (author), Grand View University, Felicitas Avendano (editor), Grand View University, Dan Chibnall (editor), Grand View University, Angela Miner (editor), Animal Diversity Web Staff.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- Palearctic
-
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- holarctic
-
a distribution that more or less circles the Arctic, so occurring in both the Nearctic and Palearctic biogeographic regions.
Found in northern North America and northern Europe or Asia.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- agricultural
-
living in landscapes dominated by human agriculture.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- heterothermic
-
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- metamorphosis
-
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- asexual
-
reproduction that is not sexual; that is, reproduction that does not include recombining the genotypes of two parents
- fertilization
-
union of egg and spermatozoan
- internal fertilization
-
fertilization takes place within the female's body
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- colonial
-
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
- chemical
-
uses smells or other chemicals to communicate
- pheromones
-
chemicals released into air or water that are detected by and responded to by other animals of the same species
- chemical
-
uses smells or other chemicals to communicate
- herbivore
-
An animal that eats mainly plants or parts of plants.
References
Adisu, B., B. Freier, C. Buttner. 2003. Effectiveness of predators and parasitoids for the natural control of Diuraphis noxia ( Homoptera : Aphididae ) on barley in central Ethiopia.. Communications in Agricultural and Applied Biological Science , 68/4: 179-188.
Armstrong, J., F. Peairs. 1996. Environmental parameters related to winter mortality of the Russian wheat aphid ( Homoptera : Aphididae ): basis for predicting mortality. Journal of Economic Entomology , 89: 1281-1287.
Becker, H. 2000. "Alarm Pheromone Knocks Off Russian Wheat Aphids" (On-line pdf). Accessed April 04, 2014 at http://vikingvoyage.grandview.edu:2249/ehost/detail?sid=933dc2d3-f0d0-47af-b9d8-9938d250cab2%40sessionmgr4003&vid=4&hid=4109&bdata=JnNjb3BlPXNpdGU%3d#db=aph&AN=3391585 .
Butts, R., G. Schaalje. 1997. Impact of subzero temperatures on survival, longevity, and natality of adult Russian wheat aphid ( Homoptera : Aphididae ). Environmental Entomology , 26: 661-667.
Caillaud, C., J. Pierre, B. Chaubet, J. Di Pietro. 1995. Analysis of wheat resistance to the cereal aphid Sitobion avenae using electrical penetration graphs and flowcharts combined with correspondence analysis. Entomologia Experimentalis et Applicata , 75/1: 9-18.
Dolatti, L., B. Ghareyazie, S. Moharramipour, M. Noori-Daloii. 2005. Evidence for regional diversity and host adaption in Iranian populations of the Russian wheat aphid. Entomologia Experimentalis et Applicata , 114/3: 171-180. Accessed March 31, 2014 at http://vikingvoyage.grandview.edu:2048/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=aph&AN=16308013&scope=site .
Hein, G., F. Baxendale, J. Campbell, A. Hagen, J. Kalisch. 1989. "G89-936 Russian Wheat Aphid" (On-line). Accessed March 01, 2014 at http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=2096&context=extensionhist&sei-redir=1&referer=http%3A%2F%2Fwww.google.com%2Furl%3Fq%3Dhttp%253A%252F%252Fdigitalcommons.unl.edu%252Fcgi%252Fviewcontent.cgi%253Farticle%253D2096%2526context%253Dextensionhist%26sa%3DD%26sntz%3D1%26usg%3DAFQjCNGEHwxqOEAO6TNkgLGIW_kS9UCiiQ#search=%22http%3A%2F%2Fdigitalcommons.unl.edu%2Fcgi%2Fviewcontent.cgi%3Farticle%3D2096%26context%3Dextensionhist%22 .
Hodgson, E., J. Karren. 2008. "Russian Wheat Aphid" (On-line). Accessed March 31, 2014 at http://extension.usu.edu/files/publications/factsheet/russian-wheat-aphids08.pdf .
Knutson, A., E. Boring, III, G. Michels Jr., F. Gilstrap. 1997. "Biological Control of Insect Pests In Wheat" (On-line). Accessed March 01, 2014 at https://insects.tamu.edu/extension/bulletins/b-5044.html .
Lai, C., P. Baumann, N. Moran. 1996. The Endosymbiont ( Buchnera sp.) of the Aphid Diuraphis noxia Contains Plasmids Consisting of trpEG and Tandem Repeats of trpEG Pseudogenes. Applied and Environmental Microbiology , 62/2: 332-339.
Merchant, M. 2014. " Diuraphis noxia " (On-line). Institute for the Study of Invasive Species. Accessed July 11, 2014 at http://www.tsusinvasives.org/database/russian-wheat-aphid.html .
Merrill, S., T. Holtzer, F. Peairs. 2009. Diuraphis noxia reproduction and development with a comparison of intrinsic rates of increase to other important small grain aphids: a meta-analysis. Environmental Entomology , 38: 1061-1068.
Merrill, S., T. Holtzer. 2010. "Estimating Russian Wheat Aphid ( Homoptera : Aphididae ) Overwintering Success Using Weather Data" (On-line pdf). Agricultural. Accessed March 01, 2014 at http://digitool.library.colostate.edu///exlibris/dtl/d3_1/apache_media/L2V4bGlicmlzL2R0bC9kM18xL2FwYWNoZV9tZWRpYS84Nzc2Ng==.pdf .
Michaud J. P, J., P. Sloderbeck. 2005. "Russian Wheat Aphid An introduced pest of small grains in the High Plains" (On-line pdf). Kansas State University. Accessed March 01, 2014 at http://www.ksre.ksu.edu/bookstore/pubs/mf2666.pdf .
Sutherland, C. 2006. "Aphids & Their Relatives" (On-line pdf). Accessed April 16, 2014 at http://aces.nmsu.edu/ces/plantclinic/documents/o-01-aphids.pdf .
Turanli, F., A. Jankielsohn, A. Morgounov, M. Cakir. 2012. The distribution of Russian Wheat Aphid, Diuraphis noxia (Kurdjumov) ( Hemiptera : Aphididae ) in Turkey. African Journal of Agricultural Research , 7/39: 5396-5404.
Zhang, B., O. Edwards, L. Kang, S. Fuller. 2012. Russian wheat aphids ( Diuraphis noxia ) in China: native range expansion or recent introduction?. Molecular Ecology , 21/9: 2130-2144. Accessed March 31, 2014 at http://vikingvoyage.grandview.edu:2048/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=aph&AN=74304023&scope=site .