Insect - Stem Borer
Scientific Name - Chilo partellus
Identification of the pest - Larva of this insect are yellowish brown in colour with brown head & adult moth is straw coloured. The grown-up caterpillars have four brownish longitudinal stripes on the back.
Damage - The caterpillars feed on the tender leaves and enter the stem, causing the middle part of the plant to dry up and the area to become dormant.
Stem borer are among the most important insect pest of maize. They cause yield loss that varies between 10-50 %.
Control - Under severe infestation, chemical control can be an effective way of managing stem borers.
At initial stage of plants, spraying of Methyl Parathion 50 EC 500-600 ml by dissolving in 500-600 litres of water @ per hectare.
Mix Phorate 10% CG 10 kg/ha or Carbaryl 4% G 20 kg/ha (granular insecticides) with sand to make up a total quantity of 50 kg and apply in the leaf whorls on the 20th day after sowing
Destroy crop residues after harvest to reduce population.
Integrated Management -
- Early sowing should be done to avoid a serious infestation.
- Collect the stubbles & destroy.
- Start monitoring weekly, 3 weeks after planting.
- To reduce damage, intercropping of maize with non-host plants such as cowpea or cassava should be done.
- To enhance the crop tolerance capacity to an attack, apply nitrogen either a commercial product or manure or compost.