2. Gall midge: Orseolia oryzae (Cecidomyiidae: Diptera)

Distribution and Status: India, Burma, Cambodia, Sri Lanka, China, Indonesia, Nigeria, Sudan, Vietnam and Pakistan.

Host range: Rice, wild species of Oryza and grasses like Paspalum scrobiculatum, Panicum spp., Cyanodan dactylon and Eleucine indica.

Damage symptoms: The maggot feeds at the base of the growing shoot causing formation of a tube like gall similar to “onion needle” or “silver-shoot”.  Infested tillers produce no panicles.

ETL:  10% silver shoots.

Bionomics: Orange coloured mosquito like fly is active during night and lays 100-300 reddish, elongate, tubular eggs just near the ligule of the leaf blade.  Egg period 3-4 days, maggot pale red during feeding and larval period 8-10 days.  Maggot pupates at the base of the gall and moves to tip of the gall and projects outside during emergence. Life cycle lasts for 15-20 days.

Management

• Encourage early planting of the crop with quick growing varieties to escape infestation.
• Use resistant varieties like MDU-3, Shakthi, Vikram, Sureka, IR 36, Kkatiya, Dhanaya Lakshmi, Phalguna, Kunti, Shamlei, Asha, Rajendran, Shrakasha, Erra mallelu, Kavya, Orugallu and R 650 -1820
• Plough immediately after crop harvest.
• Remove the alternate host.
• Apply fertilizers in balanced manner.

• Set up light trap @ 1 / ha as a monitoring device. Infra red light trap attracts gall midge effectively.
• Release larval parasitoid, Platygaster oryzae through parasitized galls @ 1 per 10 m2 in the main field at 10 days after transplanting (DAT).
• The is an effectivhe predator.
• Conserve predatory spiders like Tetragnatha, Argiope catenulata and carabid beetle (Ophionia indica) in rice ecosystem.
• Apply carbofuran 3G @ 25 kg or fipronil 0.3 G 16.7 - ­ 25.0 kg or spray endosulfan 35 EC 1.0 L or quinalphos 25 EC 1.0 L or ethofenprox 10 EC 500-750 ml or fipronil 5 SC 1.0 -1.5 kg or lambda-cyhalothrin 2.5 EC 500 ml / 5 EC 250 ml or thiamethoxam 25 WG 100 g in 500 L water/ha