riceDoctor

Rice Gall Midge

Attention: open in a new window. PrintE-mail

Image

Feeding site of immature (IRRI)

Diagnostic summary

  • tubular gall is formed at the base of a tiller
  • elongation of leaf sheaths called onion leaf or silvershoot


  • elongate-tubular eggs
  • maggot-like larva feeding inside developing buds


  • tillering stage of the rice plant
  • irrigated or rainfed wetland environments
  • presence of alternate hosts
  • cloudy or rainy weather
  • cultivation of high-tillering varieties
  • intensive management practices
  • low parasitization


 

Full fact sheet

Asian rice gall midge

Orseolia oryzae (Wood-Mason)

  • Formation of a hollow cavity or tubular gall at the base of the infested tiller
  • Gall is a silvery white hollow tube, 1 cm wide and 10-30 cm long
  • Affected tiller inhibits growth of leaves and fails to produce panicles
  • Deformed, wilted, and rolled leaf
  • Elongation of leaf sheaths called onion leaf or silvershoot
  • Plant stunting

 

Image

Tubular gall IRRI)

Image

Affected tillars (IRRI) 

Image

Onion shoots

The rice field can be checked for the presence of onion leaves or silvershoots. Larvae and pupae may be dissected from infected tillers.

The plant stunting and leaf deformity, wilting and rolling are also symptoms observed on plants caused by drought, potassium deficiency, salinity, and ragged stunt virus, orange leaf virus and tungro virus diseases.

The rolled leaves can also be associated with the symptom caused by rice thrips.

The Asian rice gall midge is found in irrigated or rainfed wetland environments during the tillering stage of the rice crop. It is also common in upland and deepwater rice. The adults are nocturnal and they are easily collected using light traps.

During the dry season, the insect remains dormant in the pupal stage. They become active again when the buds start growing after the rains.

The population density of the Asian rice gall midge is favored mainly by cloudy or rainy weather, cultivation of high-tillering varieties, intensive management practices, and low parasitization.

The Asian rice gall midge is found in irrigated or rainfed wetland environments during the tillering stage of the rice crop. It is also common in upland and deepwater rice. The adults are nocturnal and they are easily collected using light traps.

During the dry season, the insect remains dormant in the pupal stage. They become active again when the buds start growing after the rains.

The population density of the Asian rice gall midge is favored mainly by cloudy or rainy weather, cultivation of high-tillering varieties, intensive management practices, and low parasitization.

Wild rices, such as Oryza rufipogon are common alternate hosts.

Image

The larva of the Asian gall midge moves between the sheath and the stem to reach the growing point. It feeds inside the developing buds of a new tiller and release chemicals in its saliva causing the plant to grow abnormally to produce a hollow cavity or gall at the base of the tiller. The developing and feeding larva causes the gall to enlarge and elongate at the base. Gall appears within a week after larval entry. The infected tiller becomes abnormal and silvery in color.

Examination of the tubular gall shows that it is capped by a solid plug of plant tissue at the base of the point where the leaf forms.

The Asian gall midge is an important pest from the seedbed to maximum tillering stages of the rice crop.

The Asian gall midge is an important pest and can cause significant yield losses of 30-40% in some areas like Sri Lanka and parts of India.

There are cultural control practices, which are recommended against the Asian gall midge. Plowing ratoon of the previous crop and removing all off-season plant hosts can reduce infestation.

Natural biological control agents such as platygasterid, eupelmid, and pteromalid wasps, which parasitize the larvae, is effective. The pupa is host to two species of eupelmid wasps. Phytoseiid mites feed upon the eggs, whereas spiders eat the adults.

There are rice cultivars from India, Thailand, and Sri Lanka, which are resistant to the Asian gall midge.

It is difficult to control the gall midge with insecticides.

Selected references

  1. Barrion AT, Litsinger JA. 1994. Taxonomy of rice insect pests and their arthropod parasites and predators. In: Biology and management of rice insects. Manila (Philippines): International Rice Research Institute. p 13-362.

  2. Dale D. 1994. Insect pests of the rice plant. In: Biology and management of rice insects. Manila (Philippines): International Rice Research Institute. p 363-486.

  3. Katanyukul W, Kadkao S, Boonkerd S, Chandaraprapa N. 1980. Rice gall midge outbreaks in Thailand. Int. Rice Res. Newsl. 5(2):13-14.

  4. Pathak MD, Khan ZR. 1994. Insect pests of rice. Manila (Philippines): International Rice Research Institute. 89 p.

  5. Reddy DB. 1967. The rice gall midge, Pachydiplosis oryzae (Wood-Mason). In: The major insect pests of the rice plant. Proceedings of the Symposium at the International Rice Research Institute, Sept. 1964. Baltimore, Md. (USA): The Johns Hopkins Press. p 457-491.

  6. Rao PRM, Prakasa Rao PS. 1989. Gall midge (GM) outbreak on dry season rice in West Godavari District, Andhra Pradesh (AP), India. Int. Rice Res. Newsl. 14(5):28.

  7. Reissig WH, Heinrichs EA, Litsinger JA, Moody K, Fiedler L, Mew TW, Barrion AT. 1986. Illustrated guide to integrated pest management in rice in tropical Asia. Manila (Philippines): International Rice Research Institute. 411 p.

  8. Shepard BM, Barrion AT, Litsinger JA. 1995. Rice-feeding insects of tropical Asia. Manila (Philippines): International Rice Research Institute. 228 p.

  9. Soenarjo E. 1986. Parasitoids of the rice gall midge (GM) in Indonesia. Int. Rice Res. Newsl. 11(5):29.

  10. Van Vreden G, Ahmadzabidi AL. 1986. Pests of rice and their natural enemies in peninsular Malaysia. Wageningen (Netherlands): Centre for Agricultural Publishing and Documentation (Pudoc). 230 p.

Contributors:

JLA Catindig and KL Heong