Location: Crop Bioprotection Research
2018 Annual Report
Objectives
1. Demonstrate production potential for baculovirus for insect control (such as black cutworm MNPV), evaluate formulations for storage stability and residual efficacy, and identify and evaluate insect semiochemicals such as attractants or feeding stimulants that can be integrated into formulations to improve control of major insect pests of turf or other crops.
2. Determine the relationship between microbial communities and the characteristics of weeds (such as bindweed, medusahead grass, or quack grass) that make them harmful to turf, natural ecosystems, and agricultural commodities.
3. Identify viruses that can target potential key endophytes or microorganisms that contribute negative characteristics of weeds.
4. Identify, describe, and preserve microorganisms isolated from weeds as part of the characterization of microbial communities associated with important weeds.
Approach
Grasses planted as turf and pasture represent a commodity that has been underserved when considering the use of biological control based on microbial agents. For urban and athletic turf grasses, a newly discovered baculovirus offers the opportunity to develop a biological pesticide for control of the black cutworm. Research will focus on basic and applied aspects of production, formulation, and efficacy of this baculovirus for development as a biological insecticide.
Invasive weed species among range grasses such as Medusahead may obtain enhanced fitness as a result of associations with endophytic microbes. Research will utilize classic microbial and newly developed molecular techniques to characterize endophytic microbes of the weedy plants and identify those providing competitive advantages to the weeds. Subsequent research will strive to discover mycoviruses to attach the endophytes of the weedy plant, to convert the competitive advantage back to the desired crop plant.
Progress Report
Substantial progress has been made in the third year of this research project.
For Objective 1, In vivo production of the baculovirus of the black cutworm remains the most plausible approach for commercialization of a biopesticide product. Optimization of the incubation temperature increased production of wild-type virus about three fold. Laboratory evaluations demonstrated that newly hatched larvae remain highly susceptible to virus infection for about 5 days. When applied to field grown grass, the virus applications had good residual activity for several days, which (when combined with larval susceptibility) suggest that once weekly applications may provide control of this pest in the field.
ARS scientists in Peoria, Illinois made significant progress in Objective 2. ARS scientists in Peoria, Illinois extracted DNA from the invasive weed, medusahead (Taeniatherum caput-medusae) to determine what microbes reside inside the plant. The plants were sampled from their invaded range in the western United States and from their native range in Europe. These DNA samples were used to determine the microbial communities living inside the plant, based on high throughput DNA sequencing techniques. ARS scientists in Peoria, Illinois updated the collection and analysis protocols, to reflect knowledge gained during the course of the project. ARS scientists in Peoria, Illinois targeted analysis to seeds, since they can transmit these microbes from plant to offspring. These studies will allow us to determine how microbes that live inside the plant affect these weeds.
ARS scientists in Peoria, Illinois made significant progress in Objective 3. ARS scientists in Peoria, Illinois extracted nucleotide samples from individual cultures of fungal endophytes of the invasive weed, medusahead (Taeniatherum caput-medusae). A subset of the most interesting samples were used and subjected to a process to isolate potential mycoviruses. Additional studies are needed and under way to confirm and characterize these samples. Mycoviruses have the potential to alter the properties of fungi that live inside of plants, which can confer unique properties to the plant. These properties can provide increased stress tolerance to plants allowing them to out-compete other plants.
ARS scientists in Peoria, Illinois successfully completed all elements of Objective 4, which was taxonomic characterization of a collection of fungal endophytes isolated from medusahead. These strains were characterized with DNA sequencing to identify them to the species level. The strains have been prepared for long-term preservation and storage, which will allow them to be evaluated for potential commercial properties at a later date.
Accomplishments
1. Extending storage stability of biological insecticides. Maintaining viability of beneficial microbes during storage continues to be a problem for biological insecticides. Temperature and moisture availability limit the survival of microbial propagules and shorten the shelf-life of biopesticides. ARS scientists in Peoria, Illinois have demonstrated that maintaining dry conditions during storage is beneficial to the stability of the virus that infects the black cutworm. After one year at room temperature, dry formulations do not lose insecticidal activity, whereas samples at 33 degrees C and 75% relative humidity displayed decreased activity (i.e., showing half-lives of 8 months and 2 months, respectively). This information has practical importance for developing commercial products by providing product parameters necessary to achieve industry standards, which in turn increases the efficiency with which private companies could commercially produce this biopesticide. In addition, this research provides new pest control solutions for turf insects.
Review Publications
Behle, R.W. 2017. In vivo production of Agrotis ipsilon nucleopolyhedrovirus for quantity and quality. Journal of Economic Entomology. 111(1):101-107. doi: 10.1093/jee/tox315.
Cao, W., Guo, L., Du, Z., Das, A., Saren, G., Jiang, M., Dunlap, C.A., Rooney, A.P., Yu, X., Li, T. 2017. Chengkuizengella sediminis gen. nov. sp. nov., isolated from sediment. International Journal of Systematic and Evolutionary Microbiology. 67:2672–2678. doi: 10.1099/ijsem.0.002006.
Cote, G.L., Dunlap, C.A., Vermillion, K.E., & Skory, C.D. 2017. Production of isomelezitose from sucrose by engineered glucansucrases. Amylase. 1(1):82-93. doi: 10.1515/amylase-2017-0008.
Dunlap, C.A., Lueschow, S.R., Carillo, D., Rooney, A.P. 2017. Screening of bacteria for antagonistic activity against phytopathogens of avocados. Plant Gene. 11:17-22.
Dunlap, C.A., Mascarin, G.M., Romagnoli, E.M., Jackson, M.A. 2017. Rapid discrimination of Isaria javanica and Isaria poprawskii from Isaria spp. using high resolution DNA melting assays. Journal of Invertebrate Pathology. 150:88–93.
Dunlap, C.A., Ramirez, J.L., Mascarin, G.M., Labeda, D.P. 2018. Entomopathogen ID: a curated sequence resource for entomopathogenic fungi. Mycologia. 111:897-904. doi:10.1007/s10482-017-0988-2.
Dunlap, C.A., Schisler, D.A., Perry, E.B., Connor, N., Cohan, F.M., Rooney, A.P. 2017. Bacillus swezeyi sp. nov. and Bacillus haynesii sp. nov., isolated from desert soil. International Journal of Systematic and Evolutionary Microbiology. 67:2720-2725. doi: 10.1099/ijsem.0.002007.
Johnson, E.T., Proctor, R., Dunlap, C.A., Busman, M. 2017. Reducing production of fumonisin mycotoxins in Fusarium verticillioides by RNA interference. Mycotoxin Research. 34:29-37. https://doi.org/10.1007/s12550-017-0296-8.
Lu, D., Xia, J., Dunlap, C.A., Rooney, A.P., Du, Z. 2017. Salibacter halophilus gen. nov., sp. nov., isolated from a saltern. International Journal of Systematic and Evolutionary Microbiology. 67:1784–1788. doi: 10.1099/ijsem.0.001807.
Lu, D., Xia, J., Dunlap, C.A., Rooney, A.P., Du, Z. 2017. Gracilimonas halophila sp. nov., isolated from a marine solar saltern. International Journal of Systematic and Evolutionary Microbiology. 67:3251-3255. doi: 10.1099/ijsem.0.002093.
Torres-Crus, T.J., Billingsley Tobias, T.L., Almatruk, M., Hesse, C.N., Kuske, C.R., Desiro, A., Benucci, G., Bonito, G., Stajich, J.E., Dunlap, C.A., Arnold, A., Porras-Alfaro, A. 2017. Bifiguratus adelaidae, gen. et sp. nov., a new member of Mucoromycotina in endophytic and soil-dwelling habitats. Mycologia. 109(3):363-378. https://doi.org/10.1080/00275514.2017.1364958.
Xia, J., Xie, Z., Dunlap, C.A., Rooney, A.P., Du, Z. 2017. Rhodohalobacter halophila gen. nov., sp. nov., a moderately halophilic member of the family Balneolaceae. International Journal of Systematic and Evolutionary Microbiology. 67:1281–1287. doi: 10.1099/ijsem.0.001806.
Sayed, A.M., Behle, R.W. 2017. Comparing formulations for a mixed-microbial biopesticide with Bacillus thuringiensis var. kurstaki and Beauveria bassiana blastospores. Archives of Phytopathology and Plant Protection. 50:15-16, 745-760. http://dx.doi.org/10.1080/03235408.2017.1372942.
Sayed, A.M., Kim, S., Behle, R.W. 2017. Characterization of silver nanoparticles synthesized by Bacillus thuringiensis as a nanobiopesticide for insect pest control. Biocontrol Science and Technology. 27(11):1308-1326. http://dx.doi.org/10.1080/09583157.2017.1397597.
Sayed, A.M., Behle, R.W., Tiilikkala, K., Vaughn, S.F. 2018. Insecticidal activity of bio-oils and biochar as pyrolysis products and their combination with microbial agents against Agrotis ipsilon (Lepidoptera: Noctuidae). Pesticides and Phytomedicine. 33:39-52. https://doi.org/10.2298/PIF1801039S.
Mascarin, G.M., Kobori, N.N., Jackson, M.A., Dunlap, C.A., Delalibera, I. 2018. Nitrogen source affects productivity, desiccation tolerance, and storage stability of Beauveria bassiana blastospores. Journal of Applied Microbiology. 124:810-820. doi: 10.1111/jam.13694.
Dunlap, C.A., Rooney, A.P. 2018. Acinetobacter dijkshoorniae is a later heterotypic synonym of Acinetobacter lactucae. International Journal of Systematic and Evolutionary Microbiology. 68:131-132. doi:10.1099/ijsem.0.002470.
Santos, V., Mascarin, G.M., Da Silva Lopes, M., Fregolente Alves, M.C., Rezende, J.M., Viccari Gatti, M.S., Dunlap, C.A., Delaliber Junior, I. 2017. Identification of double-stranded RNA viruses in Brazilian strains of Metarhizium anisopliae and their effects on fungal biology and virulence. Plant Gene. 11:49-58. http://dx.doi.org/10.1016/j.plgene.2017.01.001.
