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PESTS OF SORGHUM :: Major Pests :: Sorghum Midge


6. Sorghum midge: Contarinia sorghicola (Cecidomyiidae: Diptera)

Distribution and status: India, Pakistan, Bangladesh, West Iran, Sri Lanka, Sudan, Java, Africa, South East Asia, South China, South America, West Indies, USA and Italy.

Hosts: Sorghum cultivated and wild species. 


Damage symptoms:
A maggot feeds on the developing grains and pupates there.  White pupal cases protruding out from the grains and chaffy grains with holes are the damage symptoms.            

             

 


 

 

Bionomics: The adult fly is small, fragile with a bright orange abdomen and a pair of transparent wings.  It lays eggs singly in developing florets resulting in pollen shedding.  A female lays about 30-35 eggs at the rate of 6-10 in each floret.  The incubation period is 3-4 days.  The maggot has four instars with duration of 8-10 days.  Larvae are colorless, but, when fully grown, they are dark orange. Larval period 9 - 11 days. The larval stage undergoes diapause in a cocoon during December - January within a spikelet.  Pupates beneath the glume. The pupal period 3 days. When the adult emerges the white pupal skin remains at the tip of the spikelet. A generation is completed in 14-16 days. The insect's rapid developmental cycle permits 9-12 generations.

 


Management

  • Grow resistant cultivars like DJ 6541, AF 28, ICSV 197, ICSV 745, ICSV 88032
  • Conserve larval parasitoids - Apanteles sp., Eupelones popa; Larval and pupal parasitoid - Tetrastichus spp.; Predators – Orius albidipennis; Tapinoma indicum
  • Give first application at nearly 90% earhead emergence and repeat after 4 or 5 days.  The insecticides recommended are spray endosulfan 35 EC 1.0 L (or) malathion 50 EC 1.0 L (or) carbaryl 50 WP 2 kg/ha or endosulfan 4 D or malathion 5 D or carbaryl 10 D or quinalphos 1.5  D at 25 kg/ha .