Orseolia oryzae - Misplaced Pages

Species of fly

Asian rice gall midge
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Diptera
Family:	Cecidomyiidae
Genus:	Orseolia
Species:	O. oryzae
Binomial name
*Orseolia oryzae* Wood-Mason, 1889
Synonyms
Cecidomyia oryzae Wood-Mason, 1889 Orseolia oryzicola Pachydiplosis oryzae (Wood-Mason, 1889)

Orseolia oryzae, also called the Asian rice gall midge, is a species of small fly in the family Cecidomyiidae. It is a major insect pest of rice. The damage to the crop is done by the larvae which form galls commonly known as "silver shoots" or "onion shoots". The rice plant is stunted and the seed heads fail to develop.

History

In 1890, an unidentified insect was found to be attacking the rice crop in Munger district of Bihar, in India. The English zoologist James Wood-Mason identified the insect as a midge, called it Cecidomyia oryzae, and wrote about it in the American Naturalist, but did not formally describe it. The original outbreak faded away, but another occurred in Mysore in 1901, and others followed. By 1922, the rice crop in Tonkin Province in northern Vietnam was devastated and in 1936, crops in Indonesia were being attacked. It was the Indian entomologist M.S. Mani who in 1934 formally described the insect, retaining the name given it by Wood-Mason, because this was already widely known. In 1941 the midge was reported to be damaging crops in China and in 1946, it was reported from Sudan. In 1951, the Chinese researchers Li and Chiu worked out its life history. Even so, until the next decade it was a minor pest. Suddenly with the Green Revolution came higher yielding but more susceptible varieties, and ever since then O. oryzae has been among the top four insect pests (overall, not just in rice) in South and Southeast Asia and China.

Description

The Asian rice gall midge is a fly about the size of a mosquito. The females are about 3.5 mm (0.14 in) long, bright red, with broad abdomens and dense short hair, while the males are slightly smaller, yellowish-brown and more slender. O. oryzae and O. oryzivora are morphologically, and even microscopically, indistinguishable, and so DNA differentiation methods have been developed.

Distribution

It is a major insect pest of rice in Southern and Southeast Asia. The pest is distributed in various regions of India, Asia, and other neighboring countries and farmers face many problems due to the monetary loss caused by this insect pest. It is also found in rice-growing regions of Africa.

Life cycle

The adults are mainly nocturnal and hide during the day. The females lay small batches of eggs (two to six) on the undersides of rice leaves, totalling 100-400 in a lifespan. The eggs are red at first, but by the time they hatch, two to four days later, they are chocolate-brown. The tiny larvae crawl down the leaf sheath till they reach the leaf axil where they bore their way into the stem. After feeding for about ten days and forming a gall, they pupate inside. Four to seven days later they use spines on the tip of the abdomen to make a hole in the gall near its tip. Here the adult insects emerge. They live for three or four days, and there may be as many as eight generations of midge in the year.

Hosts

Oryza sativa, Cynodon dactylon, and Isachne aristatum. Scientific investigation of O. sativa resistance against O. oryzae began in India in 1948, and O. oryzae virulence against these O. sativa cultivars was first observed in 1969.

Damage

The larvae of the Asian rice gall midge irritate the tissues of the rice plant which forms a gall commonly known as a "silver shoot" or "onion shoot". This is a pale cylindrical, hollow tube with a green tip replacing the normal culm (stem). The gall is formed from the walls of the leaf sheath growing together, after which the culm stops developing. The stem is stunted and the seed-head does not develop. When the adult insects emerge, the gall withers away and the shoot dies. The plant may respond by producing more tillers, but these usually become infected in their turn. The disease may be localised and patchy or widespread throughout the crop.

References

^ "Distribution Maps of Plant Pests". CABI, Distribution Maps of Plant Pests, 1984, December, Map 171 (Revised). Archived from the original on 2016-06-01. Retrieved 2013-11-22.
Behura, S. K.; et al. (August 1999). "Differentiation of Asian rice gall midge, Orseolia oryzae (Wood-Mason), biotypes by sequence characterized amplified regions (SCARs)". Insect Molecular Biology. 8 (3): 391–397. doi:10.1046/j.1365-2583.1999.83126.x. PMID 10469256. S2CID 10818034.
Katiyar, S K; et al. (2000). "Biodiversity of Asian rice gall midge (Orseolia oryzae Wood Mason) from five countries examined by AFLP analysis". Genome. 43 (2): 322–332. doi:10.1139/g99-119. PMID 10791821.
Nair, Suresh; et al. "Plant Biology". International Centre for Genetic Engineering and Biotechnology, New Delhi. Archived from the original on 2013-11-09. Retrieved 2013-11-08.
^ Reddy, D.B. (1967). The Major Insect Pests of the Rice Plant: Proceedings. IRRI. pp. 458–470. WISC:89031297997.
^ Harris, M. O.; Stuart, J. J.; Mohan, M.; Nair, S.; Lamb, R. J.; Rohfritsch, O. (2003). "Grasses and Gall Midges: Plant Defense and Insect Adaptation". Annual Review of Entomology. 48 (1). Annual Reviews: 549–577. doi:10.1146/annurev.ento.48.091801.112559. ISSN 0066-4170. PMID 12460937.
^ Economic Zoology. Rastogi Publications. 2007. pp. 110–111. ISBN 978-81-7133-876-4.
Prasad, Rabindra (2011). "Status of the Rice Gall Midge (Orseolia oryzae W.M.) in the State of Jharkhand" (PDF). Journal of Rice Research. 4 (1, 2). Archived from the original (PDF) on 2016-03-03. Retrieved 2013-11-22.
Jagadeesha Kumar, B. D.; Chakravarthy, A. K.; Doddabasappa, B.; Basavaraju, B. S. (2009). "Biology of the rice gall midge, Orseolia oryzae (Wood-Mason) in southern Karnataka". Karnataka J. Agric. Sci. 22 (3): 535–537.
Vijaykumar, L.; Chakravarthy, A. K.; Patil, S. U.; Rajanna, D. (2009). "Resistance Mechanism in Rice to the Midge Orseolia oryzae (Diptera: Cecidomyiidae)". Journal of Economic Entomology. 102 (4): 1628–1639. doi:10.1603/029.102.0430. PMID 19736778. S2CID 12306819.
"Xenotypes Of the Rice Gall Midge". Bibliotecha Digital De La Universidad De Chile. Archived from the original on 2013-11-09. Retrieved 2013-11-08.