Rice In Sri Lanka - Pests of Rice
Brown Plant Hopper
Heavy infestations produce symptoms of hopper burn.Leaves dry and turn brown after insect feeding, and patches of burned plants are often lodged.It is a vector of grassy stunt and ragged stunt virus diseases.
sensitive to attack
The rice plant is most sensitive to attack at late vegetative and reproductive stages.
The economic threshold
At booting stage is 2 per hill and at heading 5 per hill.
Since spiders are considered major predator of BPH, the economic threshold levels are adjusted according to the number of spiders present.
A number of varieties with moderate level of resistance to BPH have been developed
Bg 379-2, Bg 300, Bg 403,Bg 304,Bg 357,Bg 358,Bg 360
Ptb 33, a variety with a high level of resistance to BPH, is extensively used in the breeding program.
Effective control methods
- Cultivate resistant varieties.
- Draining the paddy field to reduce moisture help prevent BPH multiplication.
- Indiscriminate use of insecticides during vegetative stage known to cause BPH outbreaks. Use insecticides only when and where needed during vegetative stage especially for the control of leaf eating caterpillars.
- Monitor crop regularly for signs of early BPH infestations.
- Select a safer insecticide if required.
- Safer and effective insecticides are available for use during epidemics.