Progress 07/01/23 to 06/30/24

Outputs
Target Audience:This project has several target audiences. First, the seed corn industry that requires plantings that contain both Bt-expressing and non-Bt-expressing strains, leaving no guarantee of protection for non-Bt crops. Second, farmers of Bt-expressing crops, notably corn and cotton, are a major target for this product. These farmers are experiencing the resistance development in the corn earworm and the high cost of newer Bt traits. Third, sweet corn farmers relying on chemical pesticides. Our product provides the industry with opportunities to reduce chemical pesticide resistance development in the corn earworm. Several farmers are also investors in Lepidext. Lepidext has also been in communication with the agrichemical companies that have developed Bt traits. There are varied responses to our new technology which Lepidext believes can extend the utility of Bt traits and reduce chemical pesticide application. Lepidext is also in regular communication with both actual and prospective investors regarding this technology individually and through investor forums. Changes/Problems:The most time-consuming challenges were to request all permits from various agencies at different levels (federal, state, and UH) in order to actually initiate this research legally in Hawaii. Although we started permit applications as soon as the project started in July 2023, the last permit needed was approved on 03/27/2024. The main technical challenge was building a H. zea colony at the University of Hawaii (UH) due to strict permit requirements to ship lab reared pupae from the continental U.S. to Hawaii. We decided to collect eggs from the field and rear them to start a colony for our trials to begin releases sooner than if we attempted to acquire a permit. Due to starting a colony from the field we have been facing high mortality in early generations while the colony stabilizes. We also had to switch the company providing the seed corn plots which took additional time to organize. In summary, no major changes, but the project has been delayed due to reasons mentioned above. Therefore, a one-year no cost extension was requested to fulfill all project goals. What opportunities for training and professional development has the project provided?The Cheng laboratory has fulfilled the requisite training mandated by the University of Hawai'i Biosafety Office. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?Dr. Cheng's laboratory will continue to establish and maintain the H. zea colony. Field trials will start early July 2024 and will provide data on the efficacy of the InsterusHz biopesticide in the field. Lepidext will continue to optimize and scale-up InsterusHz production and will use the data obtained in the field trials to model year-round H. zea populations and continuous release of InsterusHz moths.

Impacts
What was accomplished under these goals? Lepidext is developing novel, naturally occurring biopesticides to decrease insect populations. Lepidext's first biopesticide (The Solution), InsterusHzTM, is a sexually transmitted virus that sterilizes adult moths, suppressing corn earworm (CEW) infestations and reducing subsequent generations. InsterusHzTM is a patented strain of the sterilizing entomopathogen HzNV2 (Helicoverpa zea nudivirus 2) with markedly increased sterilizing efficiency relative to the wild-type virus. Progress has been made to develop low input methods for continues and synchronous production and delivery of InsterusHz moths for use in Hawaii. During this reporting period, methods to streamline H. zea egg collection and distribution are being optimized and rearing methods for high-density larval development have been established. Lepidext has transferred these rearing techniques to their collaborating laboratory at the University of Hawaii. To assess the presence of the HzNV-2 wild-type virus in Hawai'i, pheromone traps were deployed within corn fields. Subsequent retrieval of these traps resulted in the detection of wild-type virus through PCR analysis of trapped corn earworm moths. Since the beginning of the project, Dr. Cheng's team has started a lab colony from field collected eggs of H. zea which is currently in its third generation.

Publications