Six species of steam borer attack rice.
Six species of steam borer attack rice. These are
1.Yellow steam borer.
2.White steam borer.
3.Striped steam borer.
4.gold fringed steam borer.
5. Dark headed striped steam borer.
6.Pink steam borer.
Among the steam borer the pink steam borer is less important. It is polyphagous and prefers sugarcane to rice.
What is does: Steam borers can destroy rice at any stage of the plant from seedling to maturity.
They feed upon tillers and causes dead hearts or drying of the central tillers during vegetative stage and causes white heads at reproductive stage.
Why and where it occurs: the steam borer larvae bore at the base of the plants during the vegetative stage. On older plants the bore through the upper nodes and feed towards the base.
The yellow steam borer is a pest of deep water rice. It is found in aquatic environments where there is continues flooding. Second instar larvae enclose themselves body leaf wrapping to make tubes and detach themselves from the leaf and falls onto the water surface. They attach themselves to the tiller and bore into the steam striped steam borer is most abundant in temperate countries and in none flooded areas.
Their final in stars remain dormant in temperate areas during winter.
The pink steam borer is found in upland rice. Which is grown near sugarcane or related grasses. The presences of alternate hosts encourages the pink steam borer to develop, multiply and survive during winter or dry season. Unlike other species of steam borers the pink steam borer lay bore eggs between the leaf sheath and the steam.
High nitrogenous field favours population buildup of the steam borers. Fields planted later favours more damage by the insect pest that have built up in fields that have been planted earlier.
Stubble that remains in the field can harbour steam borer larvae and or pupae.
How to identity
check the field for the flowing damage symptoms: Dead hearts or dead tillers that can be easily pulled from the base during the vegetative stages.
White heads during reproductive stage where the emerging panicles are white and unfilled or empty.
Tiny holes on the steam and tillers.
For as or fecal matters inside the damage steams.
Dead hearts and white hearts symptoms may sometimes be confused with damage caused by rats. Neck blast and black bug disease.
To confirm steam borer damage visually inspect rice crop for dead hearts in the vegetative stage. Steams can be pulled and dissected for larvae and pupae.
Why it is important: Excessive boring through the sheath can destroy the crop. Its damage can reduce the number of reproductive tillers. At late infection plant develop white heads.
Yellow steam borer damage can lead to about 20% yield loss in early planted rice crops and 80% in late planted crop White steam borer is an important pest in rain fed wet land rice.
It can on used out breaks and destroy rice fields.
Striped steam borer is one of the most important insect pests in Bangladesh. Its damage can be as high as 100% when severe.
Gold fringed steam borer can caused yield loss of about 30%.
How to manage: Use resistant varieties.
At seedbed and transplanting hand pick and destroy egg masses.
Raise level of irrigation water periodically to sub merge the egg deposited on the lower parts of the plants.
