YELLOW AND WHITE RICE STEMBORERS
White stemborer Scirpophaga innotata
Yellow stemborer Scirpophaga incertulas
Damages :
Deadheart
Whitehead
   
Management Strategies at Various Crop Growth Stages:
Crop Establishment
Vegetative (Tillering)
Reproductive (Early panicle initiation to flowering)
Ripening
  Harvest and Post Harvest
   
Stemborer information sheet life cycle Stemborer life cycle
  Stemborer population in Maligaya, Science City of Muñoz
   
   
DAMAGES
Deadheart
 
deadheart
 Central leaf whorl folds, turns brownish, dries up and dies
   
  checks Damaged shoots can be easily pulled by hand
 
  checks There is stemborer damage when tillers have tiny holes and fecal matter
 
  checks When damage occurs at early tillering stage, plant compensates by producing additional tillers and yield loss is negligible
 
 
Deadheart Infected plant
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Whitehead
 
checks Damaged tillers produce panicles that are whitish and with empty grains
   
  checks Whiteheads can be easily pulled out by hand
   
  checks There is stemborer damage when tillers have tiny holes or fecal matter
   
  checks Egg masses laid during the reproductive growth stage (panicle initiation) are critical because whiteheads may occur and yield loss could be significant
 
 
Whitehead Infected plant
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Management Strategies at Various Crop Growth Stages:
Crop Establishment    
  checks Practice synchronous planting after a fallow period.  This will deprive stemborers of continuous food supply, thus preventing continued reproduction of pest.
 
   
  checks Plant at the right time so that the crop will be harvested before the stemborer population peaks.
 
   
  checks Use resistant varieties.
   
  checks
Change varieties every two to four cropping seasons.
 
Transplanting
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Vegetative (Tillering)    
  checks Conserve natural enemies as they play an important role in regulating stemborer population.
 
     
  checks Do not apply insecticide within 40 days after planting.  Plants compensate the damage during this growth stage by producing more tillers.
 
     
  checks Apply fertilizer properly.
     
     
 
Tillering stage
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Reproductive (Early panicle initiation to flowering)
  checks Use insecticide when needed.
   
  checks Do not apply insecticide when the population of parasitoids is greater than the larvae (based on egg mass collected from the field and reared in covered bottles).  At this stage, egg mass population is usually low (less than one egg/sqm2)
 
     
  checks Apply systematic insecticide when 1-2 egg masses are observed in every square meter in the field.
 
     
     
 
Reproductive stage
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Ripening    
  checks When whiteheads appear, there is no need to apply insecticide.
     
     
     
     
     
     
     
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Ripening stage
   
       
     
Harvest and Postharvest    
  checks Rotavate the soil immediately after harvest to kill the larvae and pupae.
     
     
     
     
     
     
     
     
 
Post harvest activity
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