Location: Insect Behavior and Biocontrol Research
2020 Annual Report
Objectives
Objective 1: Improve the feasibility of using multi-tactic pest control strategies, especially through the improvement of biologically based control methods, for invasive weeds of the southern United States (e.g. tropical soda apple, air potato and Chinese tallow).
Sub-objective 1.A. Develop pre-release techniques that can be used to evaluate the impact of future biological control agents.
Sub-objective 1.B. Determine the role of North American native natural enemies attacking biological control agents on the agents’ population establishment and impact to the targeted weed.
Sub-objective 1.C. Determine release factors that increase successful establishment of weed biological control agents.
Objective 2: Develop biologically based pest control strategies for insect pests of the southern United States.
Sub-objective 2.A. Identify companion plants, commercial products and chemical compounds that i) repel whiteflies and determine their efficacy in limiting pest dispersal into crops (“push” factors), as well as ii) plants and products capable of attracting whiteflies into trap crops to facilitate control (“pull” factors).
Sub-objective 2.B. Evaluate companion or refuge plants that attract or maintain important whitefly predators.
Sub-objective 2.C. Develop an integrated cropping system combining “push-pull” crops or plant products with natural enemy refuges for sustainable biologically-based control of the whitefly.
Sub-objective 2.D. Identify parasitoids with potential as biological control agents for corn silk flies.
Sub-objective 2.E. Determine the Argentine field host range of the potential Argentine cactus moth biological control agent, Apanteles opuntiarum.
Sub-objective 2.F. Determine the effectiveness of a mating disruption technology as a sustainable management option for the cactus moth in commercial cactus production areas.
Sub-objective 2.G. Collect, identify, and distinguish between the complex of Harrisia cactus mealybugs (HCM), their plant hosts, and host specific parasitoids found in Argentina, Puerto Rico, other Caribbean Islands, and Florida.
Sub-Objective 2.H.Identify volatile chemicals from plants or oils repellent to whiteflies as basis for develop for area-wide release of repellents to protect vegetable crops.
Approach
Invasive insect pests and weeds are among the most serious problems facing agricultural and natural ecosystems throughout the United States. This project plan describes research to improve implementation of biologically based tactics for non-pesticide management of insect pests and weeds. The goals will be achieved through acquiring a better understanding of the pest species biology along with the interactions between host plants and natural enemies to support the development of optimized approaches, technologies and strategies for control of a variety of targets. One area of research will address improvement of techniques to enhance release success and increased efficiency of establishment and impact of biological control insect species against invasive weed species, specifically targeting the air potato and Chinese tallow. A second area of research focuses on the development of an integrated vegetable cropping system for control of whiteflies using a “push/pull” pest management approach. A vegetable crop system will be assessed using ‘push’ components consisting of naturally repellent plants or plant compounds, in conjunction with ‘pull’ components that consist of trap crops and refuge plants that naturally harbor whitefly predators. The potential use of parasitoids for reduction of the impact of corn silk flies on sweet corn will also be examined. A third area of emphasis is on the protection of U.S. native cacti from the invasive Argentine cactus moth and the Harissia cactus mealybug complex. Control of the Argentine cactus moth will be assessed through the use of a mating disrupting pheromone along with a potential exotic parasitoid. Control of the Harissia cactus mealybug complex will be based on developing an understanding of the species complex composition, alternative host plant reservoirs and potential parasitoids.Identification of volatile repellent chemicals to whiteflies will be determined as the basis for development of area-wide release of repellents to protect vegetable crops. The outcomes of this research project will improve the sustainability of agricultural production, reduce reliance on pesticides and reduce the environmental degradation caused by invasive pest insect and weed species.
Progress Report
The research efforts of ARS researchers in Gainesville, Florida, resulted in significant progress towards the two objectives and subobjectives for this project. Significant progress was made under Objective 1 on developing a biological control program against the Harrisia cactus mealybug (HCM), a pest devastating the columnar cactus in the protected dry forest of Puerto Rico. To identify the source of the pest cactus-feeding mealybugs, HCM collected from various host plants at differing locations around the world were characterized using genetic identification. The original HCM species group was found to be comprised of five different species of mealybugs with each species feeding on specific host plants. The mealybugs feeding on species of amaranth plants in Puerto Rico and Florida originated from northeastern Brazil and were a non-pest invasive species. The mealybugs infesting cactus in Puerto Rico were an invasive species from southeastern Brazil and genetically identical to cactus-feeding mealybugs in California. Fortunately, the California pest mealybug population was eradicated by state authorities, but a concern exists that additional introductions could occur. Knowing the geographic origin of the Puerto Rican mealybug focuses the need to search for natural enemies as biological control agents from southeastern Brazil before another invasive introduction occurs in North America. Under Sub-Objective 2A-C significant progress was made on demonstrating that cultural control through companion planting may aid in mitigating damage by the sweet potato whitefly and aphids, invasive insects on organic vegetable crops in protected structures. Under Sub-Objective 2G significant progress was made on corn silk flies that infest sweetcorn in Florida. Three species of corn silk flies but no parasitoids were obtained from sweet corn fields at locations of high fly populations and established in laboratory culture. Parasitoid species were evaluated for their ability to parasitize pupae buried in the soil and several were capable of sub-surface parasitism. When evaluating different factors affecting the depth of pupation by fly larvae, soil type, moisture and presence of roots affected depth of pupation and similarly affected parasitism. Several pupal parasitoid species provide promise for eventual use for biocontrol of corn silk flies in the field.
Accomplishments
1. Biological control of the cactus mealybug pest in Puerto Rico. The Harrisia cactus mealybug (HCM) was introduced into Puerto Rico around 2000 and is destroying several native cactus species in the dry forest habitat of Puerto Rico. The HCM has also invaded Florida (feeding on amaranth plants) and California (feeding on cactus), causing concerns for the safety of native cactus in North America. To identify the source of the pest cactus-feeding mealybugs, ARS researchers in Gainesville, Florida, collected HCM from various host plants at differing locations around the world and characterized them using genetic identification. The original HCM species group was found to be comprised of five different species of mealybugs with each species feeding on specific host plants. The mealybugs feeding on species of amaranth plants in Puerto Rico and Florida originated from northeastern Brazil and were a non-pest invasive species. The mealybugs infesting cactus in Puerto Rico were an invasive species from southeastern Brazil and genetically identical to cactus-feeding mealybugs in California. Fortunately, the California pest mealybug population was eradicated by state authorities, but a concern exists that additional introductions will occur. Knowing the geographic origin of the Puerto Rican mealybug focuses the need to search for natural enemies as biological control agents from southeastern Brazil before another invasive introduction occurs in North America.
Review Publications
Silvestri, L., Sosa, A., Mckay, F., Vitorino, M.D., Hill, M., Zachariades, C., Hight, S.D., Weyl, P., Smith, D., Djeddour, D., Mason, P.G. 2019. Implementation of access and benefit-sharing measures has consequences for classical biological control of weeds. Biocontrol. https://doi.org/10.1007/s10526-019-09988-4.
Varone, L., Gonalons, C.M., Faltlhauser, A.C., Guala, M.E., Wolaver, D., Srivastava, M., Hight, S.D. 2020. Effect of rearing Cactoblastis cactorum on an artificial diet on the behavior of Apanteles opuntiarum. Journal of Applied Entomology. 144:278-286. https://doi.org/10.1111/jen.12731.
Massimi, M., Haseeb, M., Legaspi, J.C. 2020. Growth biometrics response of silage corn and forage sorghum to hybrid vigor under multiple irrigation treatments. International Journal of Agricultural Science. 5:14-24.
Triapitsyn, S.V., Hight, S.D., Logarzo, G.A., Aguirre, M.B., Verle Rodrigues, J., Trjapitzin, V.A., Rivera Ocasio, Z., Rivera-Vazques, M., West Ortiz, M.J., Rodriguez Reyes, Y. 2020. Natural enemies of the Harrisia cactus mealybug and other Hypogeococcus species (Hemiptera:Pseudococcidae) in Puerto Rico:Identification and taxonomic notes on primary and secondary parasitoids. Neotropical Entomology. 49:369-391. https://doi.org/10.1007/s13744-019-00754-w.
Kanga, L., Siebert, S.C., Sheikh, M., Legaspi, J.C. 2019. Pesticide residues in conventionally and organically managed apiaries in south and north Florida. Current Investigations in Agriculture and Current Research (CIACR). 7(3):000262. https://doi.org/10.32474/CIACR.
Wu, P., Haseeb, M., Zhang, R., Kanga, L.H., Legaspi, J.C. 2019. In vitro consumption patterns of pepper weevil, Anthonomus eugenii (Coleoptera: Curculionidae) on two commercial pepper cultivars in Florida. Applied Entomology and Zoology. 54:473-479. https://doi.org/10.1007/s13355-019-00645-x.
Wu, P., Haseeb, M., Diedrick, W., Ouyang, H., Zhang, R., Kanga, L.H., Legaspi, J.C. 2019. Influence of plant direction, layer and spacing on the infestation levels of Anthonomus eugenii (Coleoptera: Curculionidae) in open jalapeño pepper fields in north Florida. Florida Entomologist. 102(3):501-508. https://doi.org/10.1653/024.102.0319.
Legaspi, J.C., Miller, N.W., Kanga, L.H., Haseeb, M., Zanuncio, J.C. 2020. "Attract and reward” for syrphid flies using methyl salicylate and sweet alyssum in kale in north Florida. Subtropical Agriculture and Environments. 71:49-52.
Perez-De La O, N., Spinosa-Zaragoza, S., Lopez-Martinez, V., Hight, S.D., Varone, L. 2020. Ecological niche modeling to calculate ideal sites to introduce a natural enemy: The case of Apanteles opuntiarum (Hymenoptera: Braconidae) to control Cactoblastis cactorum (Lepidoptera: Pyralidae) in North America. Insects. 11(7):454. https://doi.org/10.3390/insects11070454.
Carvalho, J.N., Silva, F.W., Leito, G.D., Azevedo, A.M., Teixeira, G.L., Soares, M.A., Zanuncio, J.C., Legaspi, J.C. 2020. Does fertilization with dehydrated sewage sludge affect Terminalia argentea (Combretaceae) and associated arthropods community in a degraded area? Scientific Reports. 10:11811. https://doi.org/10.1038/s41598-020-68747-z.
