In 2016, the U.S. planted 94, 004, 000 acres of corn with a value of $51.5 billion. Unfortunately half of the sweet corn planted in the U.S. is unsalable due to corn ear damage caused by insect pests. Because of insects, $30 per acre of corn was spent on pest management or lost to damaged crops in 2003. If that figure is currently accurate, then over $3 billion was lost to insect control or damage in 2016. The most devastating insect culprits are the polyphagous caterpillars, because once they eat their preferred plant, they span out to invade other significant cash crops in a single season. For example, the corn earworm--Helicoverpa zea--prefers corn, but once corn senesces, the corn earworm will feed upon and damage soybean, sorghum, and cotton. The cost of crop loss and pest control for just the corn earworm is greater than $988 million in cotton throughout the U.S. In 2016, 42% of the 83.7 million soybean acres in the U.S. were infested with corn earworms, costing producers an average $10 per acre or $837 million. The corn earworm can also attack 50 other crops and is one of the United States' most costly insect pests, regularly costing in excess of $2 billion per year. Current strategies to control the corn earworm rely on Bt-crops, natural predators, direct silk treatment, and insecticides to reduce pest populations. While these techniques are usually effective, some are laborious and at times fail to reduce pest numbers below the economic threshold during large infestations. The corn earworm has also become resistant to some insecticides and Bt-crops. Thus, there is a continual need to develop additional methods to sustainably control this pest. In the U.S., there is an increasing demand for biopesticides, chemical-free crops, and organic farm products due to environmental mindfulness and concerns about the safety of synthetic insecticides and transgenic crops. There is significant need for effective methods to reduce corn earworm populations with non-chemical methods that do not genetically modify the plant. We can control corn earworm populations with a new viral biopesticide that is sexually transmitted within corn earworm moth populations and sterilizes infected insects. Thus farmers using this technology do not need to apply chemicals or use GMO crops. This new nudivirus technology relies upon a mutant HzNV-2 nudivirus (KS-45) that causes ? 95% sterility when transmitted from an infected mother to her offspring. We hypothesize, and our data strongly suggest, that such an efficiently transmitted sterilizing virus can cause localized population suppression of this devastating crop pest. The main purpose of this project is to develop a cost-effective system to manufacture sterile insects and test that those sterile insects cause population collapse once released into a colony. We anticipate that we can generate over 500, 000 sterile insects from one day's work. We also expect that those sterile insects will transmit the sterilizing condition into native populations and significantly reduce the number of corn earworm insects. The anticipated benefit of smaller corn earworm populations is that the number of unsalable damaged crops is significantly reduced. Our data will be used to obtain an international patent for the KS-45 virus, to obtain an experimental use permit from the EPA to perform field studies, to address regulatory issues, and to determine if sterility occurs in the related insect pest, Helicoverpa armigera, the old world bollworm. The old world bollworm was strictly an Eastern hemisphere pest until 2008, when it was discovered in Brazil. It was found in the U.S. in 2015.The ultimate goal of the project is to supplement or replace chemical pesticides and transgenic crops with a virus that infects selected moth species, is sexually transmitted within those pest species, and has little environmental risk to non-target insects because the parental virus already exists in targeted pest populations. The KS-45 nudivirus can be...
