Keyun®HearNPV is based a naturally occurring pathogenic virus, Helicoverpa armigera nucleopolyhedrovirus (HearNPV) that infects and kills only larvae of corn earworm, cotton bollworm and other Helicoverpa spp specices.

  • Use for
  • How it works
  • Product specifications
  • Directions for use
  • Product handling

Use for

Use for

Corn earworm, cotton bollworm and other Helicoverpa species.

How it works

How it works

When Keyun®HearNPV is applied to crops and ingested by pests, the virions are released and replicate massively in the pest's body, and then spread throughout the body while rapidly consuming body tissues. Helicoverpa spp that ingest the virus become lethargic during their sickness caused by the virus infection, and appear sublethal. Eventually, they will die with their internal organs and tissues liquefied. In addition, the virions will continue to spread like a plague between and through several generations of Helicoverpa spp through the fluid or feces of the dead Helicoverpa spp larvae, providing effective long-term control of the Helicoverpa spp population.

Product specifications

Product specifications

1. Formulation: WG

  • Concentration: 6.0×10^10PIB/g

2. Formulation: SC

  • Concentration: 5.0×10^9PIB/ml

Directions for use

Directions for use


The homogenously diluted solution can be made by premixing Helivex with a small amount of water and vigorously agitating before adding to the tank. Spray water pH should be neutral(pH7.0). Spray water pH above 8 may damage the virus and performance will be reduced. If mixing with other pesticides or foliar fertilizers in water, add Helivex to the spray tank after the other products are thoroughl diluted. Keyun®HearNPV should be applied as soon as possible after mixing. The virus can be rendered inactive if the mixture is left to stand overnight.


Application rate


Target Pest

Rates and Dilution Rates

Application Method

Cotton,Sweet Corn and Other Vegetable Crops

Helicoverpa spp.

1. WG: 30-45grams/ha;

2. SC: 360-540ml/ha

 Keyun®HearNPV can be applied at the low label rate (30 grams)as preventative, or when pest pressure is low. If pest pressure is high, or the overlapping is serious, Keyun®HearNPV can be applied at high label rate(45 grams) OR by mixing or rotate with another insecticide that will provide more rapid knock-down of Helicoverpa armigera.

Multiple sprays at low rates and short intervals are likely to provide better control than a single spray at high rate.


Application Method

Keyun®HearNPV can be applied using standard ground sprayers, aerial application, and overhead sprinkler chemigation. Apply Keyun®HearNPV in sufficient water to obtain thorough coverage of the crop canopy without excessive runoff. Actual application volume will depend on the type of spray equipment used. It is advised to use nozzles with Ultra-low volume spraying to ensure thorough coverage of the target area.

Application Timing

Keyun®HearNPV must replicate within the host larva in order to be effective, so Keyun®HearNPV is slower to kill larvae compared to many chemical insecticides. Several days may elapse between treatment and cessation of larval feeding due to virus infection. Larvae may cause considerable damage as they continue to feed even if they eventually succumb to virus infection. Therefore, Keyun®HearNPV applications should be targeted against FIRST OR SECOND INSTAR LARVAE in order to avoid the occurrence of extensive damage. The subsequent applications should be made at 3-6 days interval depending on the eggs counts and crop growth rate due to the short residual activity of virus.



Keyun®HearNPV can be applied alone against Helicoverp armigera if Helicoverpa armigera is a key pest or when non-target pests do not reach economic threshold. However, Helivex is highly compatible with the majority of herbicides, insecticides fungicides and foliar fertilizers in order to provide a broader spectrum of control(including more rapid know-down effect), to kill moths and eggs as well as larvae, or to control Helicoverpa armigera larvae resistant to chemical insecticides. Keyun®HearNPV will infect and kill both susceptible and resistant larvae. Ensure that the mixture has a pH of 7 or less. Mixing Keyun®HearNPV with alkaline substances will damage the virus.

Rain Fastness and Use of Spray Adjuvants

The majority of virus uptake by larvae occurs within 1 hour post-application. For this reason, it is best to avoid applying Keyun®HearNPV if heavy rain is expected within one hour following applications. However, do not delay application if only moderate rain is expected, or heavy rain is not imminent. Use of spreader/sticker and ultraviolet screening agent can enhance the performance of Keyun®HearNPV. Additional protection, as well as enhanced spray deposition and rain fastness, may be obtained by using certain latex, mineral oils and powdered skim milk. Avoid mixing Keyun®HearNPV with silicone-based adjuvants intended only as spreader. Such compounds may interfere with the natural ability of the virus to stick to plant surfaces.

Product handling

Product Handling

Temperature Conditions during Transport


Storage Time at Different Temperatures

  • >2  years at -18℃
  • 2 years at <+5℃
  • 1 month at<+25℃