Panicle rice mite
Encyclopedia
Steneotarsonemus spinki, also known as Panicle rice mite, spinki mite and rice tarsonemid mite, is a serious rice
pest in several Asia
n tropical regions, Central America
and the Caribbean
.
is required to observe it on the inside of the leaf
sheath. The mites are clear to straw-colored and are approximately 250 µm in length. The male has elongated rear legs containing a pair of elongated spines. The legs are carried above the body. Males are highly active and can be seen moving on the surface of the leaf. Females are ovoid-shaped. Larva
l stages, as well as eggs are about half the size of adults.
in the laboratory
can vary from 3 days at 86 ºF to 20 days at 68 ºF. If held in the laboratory at 17.6 ºF for 72 hours, all parnicle rice mites will die.
High temperatures and low rainfall are ideal for development of large populations of parnicle rice mites in the field
. Continuous rice culture and the sharing of equipment between fields is also conducive to building damaging populations of the mites.
The mite has been extremely destructive in rice fields of tropical regions of Asia, particularly in China
and Taiwan
, and in and Central America. The mite has wiped out commercial rice fields in the Caribbean region.
The panicle rice mite was first introduced into the United States
in 2007, and has been found in Louisiana
, Arkansas
, Texas
, Ohio
and New York. Until the discovery at UC Davis
, it had never been identified in California
or elsewhere in the western United States. On July 13, 2007, the United States Department of Agriculture
confirmed the presence the panicle rice mite at a rice research facility in Alvin
, Brazoria County, Texas
. Other interceptions of this pest have also been reported at greenhouse
s in Ohio and Texas within the last 10 years.
In January, 2009, officials at 11 University of California Davis greenhouses discovered panicle rice mite contamination.
Although panicle rice mites are not thought to have the ability to thrive in the temperate climate of the United States, the area of southwest Louisiana has a sub-tropical climate with both high temperature and high humidity.
Panicle rice mites thrive under both of these conditions and may cause substantial economic losses when found in association with Burkholderia glumae
(bacterial panicle blight) and Sarocladium oryzae
(sheath rot) pathogen
s. These pathogens are both present in southwest Louisiana.
), and completes its development on the invasive plant Oryza latifolia.
Feeding takes place behind the leaf sheath. The feeding lesion can be detected by cinnamon
to chocolate
-brown discoloration of the leaf sheath. When a new leaf begins development, a female will move to the new leaf sheath, produce male offspring and then establish a new feeding lesion. Thus, damage will often be observed on interior sheaths when the outer sheath is removed. This continues until the mite reaches the leaf nearest the stem. They also feed on developing panicles from the boot stage to the milk stage of heading.
Panicle rice mites cause damage to plants by directly by feeding on leaf tissue in the leaf sheath and developing grains at the milk stage, and indirectly, by transmitting fungal
pathogens. During feeding, they inject a toxic
saliva
. The mites have been associated with sheath rot as well as bacteria
l panicle blight. The mites can carry sheath rot spores on their body.
The mites cause damage to plant tissue which may facilitate entry of fungal pathogens into developing grains and the leaf sheath. This damage to grains results in sterility and deformed grains, straight-head, and parrot-beaking of grains.
Crop losses ranging from 5% - 90% have been attributed to parnicle rice mites a number of countries.
In the Americas, however, it has caused the largest economic impact. In Central America it has caused yield losses ranging from 30% to 90%.
These cultural control methods as well as breeding for resistance have successfully suppressed populations in some infested countries.
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
pest in several Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
n tropical regions, Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
.
Identification
The panicle rice mite is not visible to the naked eye. A minimum 20× hand lensLens (optics)
A lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element...
is required to observe it on the inside of the leaf
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
sheath. The mites are clear to straw-colored and are approximately 250 µm in length. The male has elongated rear legs containing a pair of elongated spines. The legs are carried above the body. Males are highly active and can be seen moving on the surface of the leaf. Females are ovoid-shaped. Larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
l stages, as well as eggs are about half the size of adults.
Life history
Parnicle rice mites are parthenogenetic (virgin females can produce male offspring). The female will then mate with the male offspring and produce eggs. A mated female produces an average of 55 eggs in her lifetime. The lifecycleBiological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
in the laboratory
Laboratory
A laboratory is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories...
can vary from 3 days at 86 ºF to 20 days at 68 ºF. If held in the laboratory at 17.6 ºF for 72 hours, all parnicle rice mites will die.
High temperatures and low rainfall are ideal for development of large populations of parnicle rice mites in the field
Field
-Places:* Field, British Columbia, Canada* Field, Minneapolis, Minnesota, United States* Field, Ontario, Canada* Field Island, Nunavut, Canada* Mount Field - Expanses of open ground :* Field...
. Continuous rice culture and the sharing of equipment between fields is also conducive to building damaging populations of the mites.
Distribution
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
and Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, and in and Central America. The mite has wiped out commercial rice fields in the Caribbean region.
The panicle rice mite was first introduced into the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
in 2007, and has been found in Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
, Arkansas
Arkansas
Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...
, Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
and New York. Until the discovery at UC Davis
University of California, Davis
The University of California, Davis is a public teaching and research university established in 1905 and located in Davis, California, USA. Spanning over , the campus is the largest within the University of California system and third largest by enrollment...
, it had never been identified in California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
or elsewhere in the western United States. On July 13, 2007, the United States Department of Agriculture
United States Department of Agriculture
The United States Department of Agriculture is the United States federal executive department responsible for developing and executing U.S. federal government policy on farming, agriculture, and food...
confirmed the presence the panicle rice mite at a rice research facility in Alvin
Alvin, Texas
Alvin is a city in the U.S. state of Texas within the Houston–Sugar Land–Baytown metropolitan area and Brazoria County. As of the 2000 U.S. Census, the city population was 21,413. Alvin's claim to fame is Baseball Hall of Famer Nolan Ryan, who moved with his family to the city in 1947 as...
, Brazoria County, Texas
Brazoria County, Texas
Brazoria County[p] is a county in the U.S. state of Texas, located on the Gulf Coast within the Houston–Sugar Land–Baytown metropolitan area. Regionally, parts of the county are within the extreme southern-most fringe of the regions locally known as Southeast Texas. Brazoria County is among a...
. Other interceptions of this pest have also been reported at greenhouse
Greenhouse
A greenhouse is a building in which plants are grown. These structures range in size from small sheds to very large buildings...
s in Ohio and Texas within the last 10 years.
In January, 2009, officials at 11 University of California Davis greenhouses discovered panicle rice mite contamination.
Although panicle rice mites are not thought to have the ability to thrive in the temperate climate of the United States, the area of southwest Louisiana has a sub-tropical climate with both high temperature and high humidity.
Panicle rice mites thrive under both of these conditions and may cause substantial economic losses when found in association with Burkholderia glumae
Burkholderia glumae
Burkholderia glumae is a Gram-negative soil bacterium....
(bacterial panicle blight) and Sarocladium oryzae
Sarocladium oryzae
Sarocladium oryzae is a plant pathogen causing the sheath rot disease of rice. In culture it produces 0.3–0.627 micrograms of helvolic acid and 0.9–4.8 micrograms of cerulenin per milliliter of culture medium. The level of helvolic acid correlated with a higher incidence of sheath rot...
(sheath rot) pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
s. These pathogens are both present in southwest Louisiana.
Host plants
Panicle rice mites are pests of commercial rice (Oryza sativaOryza sativa
Oryza sativa, commonly known as Asian rice, is the plant species most commonly referred to in English as rice. Oryza sativa is the cereal with the smallest genome, consisting of just 430Mb across 12 chromosomes...
), and completes its development on the invasive plant Oryza latifolia.
Damage
Cinnamon
Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods...
to chocolate
Chocolate
Chocolate is a raw or processed food produced from the seed of the tropical Theobroma cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America. Its earliest documented use is around 1100 BC...
-brown discoloration of the leaf sheath. When a new leaf begins development, a female will move to the new leaf sheath, produce male offspring and then establish a new feeding lesion. Thus, damage will often be observed on interior sheaths when the outer sheath is removed. This continues until the mite reaches the leaf nearest the stem. They also feed on developing panicles from the boot stage to the milk stage of heading.
Panicle rice mites cause damage to plants by directly by feeding on leaf tissue in the leaf sheath and developing grains at the milk stage, and indirectly, by transmitting fungal
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
pathogens. During feeding, they inject a toxic
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...
saliva
Saliva
Saliva , referred to in various contexts as spit, spittle, drivel, drool, or slobber, is the watery substance produced in the mouths of humans and most other animals. Saliva is a component of oral fluid. In mammals, saliva is produced in and secreted from the three pairs of major salivary glands,...
. The mites have been associated with sheath rot as well as bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
l panicle blight. The mites can carry sheath rot spores on their body.
The mites cause damage to plant tissue which may facilitate entry of fungal pathogens into developing grains and the leaf sheath. This damage to grains results in sterility and deformed grains, straight-head, and parrot-beaking of grains.
Crop losses ranging from 5% - 90% have been attributed to parnicle rice mites a number of countries.
In the Americas, however, it has caused the largest economic impact. In Central America it has caused yield losses ranging from 30% to 90%.
Chemical
Chemical controls are usually not efficacious because the mites remain present in a water-sealed area of the plant -- behind the leaf sheath and near the stem. Thus, systemic miticides may be the best option for chemical control.Cultural
Cultural controls include plowing stubble after harvesting crops, as well as ensuring no re-growth of plant material for winter, fallowing fields, rotation with an alternate crop, cleaning machinery before use in an un-infested field, sampling two weeks after planting to catch mite populations at low levels, and avoidance of second-cropping.These cultural control methods as well as breeding for resistance have successfully suppressed populations in some infested countries.
Further reading
- Pest management in rice in tropical Asia
- Steneotarsonemus spinki in Taiwan
- Ho, C.C. and K.C. Lo. 1979. A survey of the host ranges of Steneotarsonemus spinki (Acari: Tarsonemidae). National science Council Monthly. 7(10): 1022-1028. [Article in Chinese; Abstract in English].
- Jiang, P.Z. et al. 1994. Regularity of incidence of Steneotarsonemus spinki and its control. Guangdong Agricultural Sciences. 5: 37-40. [Article in Chinese; Abstract in English].
- Lo, K.C. and C.C. Ho. 1980. The rice tarsonemid mite Steneotarsonemus spinki. Plant Protection Bulletin Taichung. 22(1): 1-10. [Article in Chinese; Abstract in English].
- Lo, K.C. et al. 1979. Artificial propagation of Amblyseius taiwanicus Ehara and its tolerance of some pesticides. Journal of Agricultural Research China. 28(4): 251-259. [Article in Chinese; Abstract in English].
- Lo, K.C. et al. 1981. Screening of chemicals for the control of rice tarsonemid mite, Steneotarsonemus spinki. Journal of Agricultural Research China. 30(3): 303-307. [Article in Chinese; Abstract in English].
- Ochoa, R. 2004a. E-mail from Dr. Ronald Ochoa to Mr. Keith Colpetzer dated 12 March 2004. Subject: telephone conversation 3-12-2004. On file with USDA, APHIS, PPQ.
- Ochoa, R. 2004b. E-mail from Dr. Ronald Ochoa to Dr. Robert (Bob) Carlson dated 02 February 2004. Subject: Steneotarsonemus spinki (Acari: Tarsonemidae) New to Ohio and USA. On file with USDA, APHIS, PPQ.
- PIN309, 2004. Port Information Network: Pest Interceptions (309) Application. USDA, APHIS, PPQ. (Queried 18 March 2004).
- Ramos, M. and H. Rodríguez. 2001. Aspectos biológicos y ecológicos de Steneotarsonemus spinki en arroz, en Cuba. Manejo Integrado de Plagas. 61: 48-52.
- Ramos, M. et al. 2001. Presencia de Steneotarsonemus spinki Smiley (Acari: Tarsonemidae) en cuatro variedades de arroz en le Republica Dominicana. Revista de Proteccion Vegetal. 16(1): 6-9.
- Rao, J. and A. Prakash. 2002. Paddy field weed, Schoenoplectus articulatus (Linn.) Palla (Cyperaceae): A new host of tarsonemid mite, Steneotarsonemus spinki Smiley, and panicle thrips, Haplothrips ganglbaureri Schmutz. Journal of Applied Zoological Research. 13(2/3): 174-175.
- Rao, P.R.M. et al. 2000. Spikelet sterility/grain discoloration in rice in Andhra Pradesh, India. International Rice Research Notes. 25(3): 40.