Location: Commodity Protection and Quality Research
2023 Annual Report
Accomplishments
1. Asian citrus psyllid control using ethyl formate. Asian citrus psyllid (ACP) is a devastating pest of citrus, as it spreads the disease Huanglongbing that curtails fruit yield and quality. Southern California is impacted by ACP quarantines whereas the packing and juicing operations in the San Joaquin Valley of California are not. ARS scientists in Parlier, California, developed a postharvest fumigation treatment with ethyl formate to control ACP after fruit is binned and loaded on a trailer prior to transportation from the grove. This innovative treatment limits ACP spread and reduces broad-spectrum insecticide use. ARS scientists also developed an ethyl formate treatment that will begin replacing methyl bromide treatments of imported table grapes from Chile, which represents the greatest U.S. usage of this fumigant on fresh fruit. Data generated by this research was submitted to the US Environmental Protection Agency and California Department of Pesticide Regulation to support Section 3, Federal Insecticide, Fungicide, and Rodenticide Act registration.
2. Control of invasive and quarantine horticultural pests. Brown marmorated stink bug (BMSB) adults overwinter in container consignments and vehicles, many of which are exported to countries requiring a phytosanitary treatment to control this invasive insect pest that damages fruit, vegetable, and ornamental crops. In 2022, ARS scientists in Parlier, California, were asked to develop a treatment that could be applied on-arrival in Australia and New Zealand. An ethyl formate fumigation protocol was developed to control BMSB, resulting in market retention for the export of automobiles to Australia and New Zealand with a projected annual value of USD $10 billion.
3. Identification of insecticide resistance in Gill’s mealybug. The Gill’s mealybug (GMB) is a serious pest of pistachios in California. Insecticide treatment is the primary control method, but growers have experienced control failures since 2019. The cause of these failures was unknown. An ARS researcher in Parlier, California, screened field populations from the Central Valley of California, and found that a population from Hanford was resistant to acetamiprid. The insecticide resistance level identified in this research, although relatively low, indicated that there has been repeated pressure to select for acetamiprid resistance in GMB. Acetamiprid resistance levels can increase if effective GMB management steps are not taken which will decrease the ability to manage this pest. This information will alert growers that they need to rotate to a different insecticide family to delay resistance.
4. Field observations of the response of navel orangeworm males to synthetic pheromone lures. Determining the impact of the biological clock and external temperature on the timing of sexual activity of moth pests like the navel orangeworm is important for optimization of control technologies based on pheromone mating disruption. An ARS researcher in Parlier, California, in collaboration with colleagues from California State University, Fresno, and University of California, Riverside, gathered and analyzed two years of camera trap data to build on information from previous studies based only on field observations of males attracted by laboratory-reared females. Males exhibited the greatest sexual activity in the last few hours before sunrise in summer conditions and began mating earlier in cooler times of the year. Unlike previous reports, it was noted that peak time of capture changed with season but not with transient temperature changes. Improved understanding of day-night patterns of male activity will improve our understanding of monitoring data and enable optimization of mating disruption for the navel orangeworm. Improved control based on this understanding could reduce insecticide used to control this primary pest of almonds and pistachios planted on approximately 1.5 million acres of land with an annual farm gate value of nearly $8.5 billion.
5. Identifying pistachio hull factors associated with insect damage to improve quality. The navel orangeworm (NOW), Amyelois transitella, is the primary insect pest of pistachios, a specialty crop worth over $2.5 billion in California. Improving the understanding of NOW biology and interaction with its pistachio host is required to reduce damage by identifying high risk orchards. NOW controls costs more than $50 million annually. An ARS researcher in Parlier, California, conducted an 11-year study using processor grade sheet information to identify nut factors associated with increased insect damage. Two nut factors related to early hull split, percent adhering hull and dark staining, were strongly correlated with damage. An improved grower understanding of the management practices that cause early hull split, including irrigation practices, will reduce the frequency of its occurrence, thereby reducing insect damage and increasing nut quality.
Review Publications
Obenland, D.M., Leyva-Gutierrez, F., Wang, T. 2022. Investigations into determinants of blueberry coating effectiveness. Foods. 12(1). Article 174. https://doi.org/10.3390/foods12010174.
Burks, C.S., Hengst, F.S., Wilson, H., Wenger, J.A. 2022. Diel periodicity in males of the navel orangeworm (Lepidoptera: Pyralidae) as revealed by automated camera traps. Journal of Insect Science. 22(5). Article 11. https://doi.org/10.1093/jisesa/ieac059.
Obenland, D.M., Arpaia, M. 2023. Managing postharvest storage issues in ‘Shiranui’ mandarin. HortTechnology. 33(1):118-124. https://doi.org/10.21273/HORTTECH05133-22.
Bansal, R., Hunter, W.B., Haviland, D.R. 2023. Baseline susceptibility and evidence of resistance to acetamiprid in Gill’s mealybug, Ferrisia gilli Gullan (Hemiptera: Pseudococcidae). Journal of Economic Entomology. 116(2):554-559. https://doi.org/10.1093/jee/toad012.
Siegel, J.P. 2023. Nut factors associated with navel orangeworm, Amyelois transitella (Lepidoptera: Pyralidae) damage to pistachio (Pistacia vera) in California (2007-2017) and implication for control. Journal of Economic Entomology. 116(3):882-890. https://doi.org/10.1093/jee/toad051.
Goane, L., Carrizo, B., Ruiz, M., Bachmann, G.E., Milla, F., Segura, D., Kuzmich, D., Walse, S.S., Vera, M. 2023. Behavioural and electrophysiological response of Anastrepha fraterculus (Diptera: Tephritidae) to a gamma-lactone synthetic semiochemical. Insects. 14(2). Article 206. https://doi.org/10.3390/insects14020206.
Coates, B.S., Walden, K.O., Lata, D., Vellichirammal, N.N., Mitchell, R.F., Andersson, M.N., Mckay, R., Lorenzen, M.D., Grubbs, N., Wang, Y., Han, J., Xuan, J., Willadsen, P., Wang, H., French, B.W., Bansal, R., Sedky, S.F., Souza, D., Bunn, D., Meinke, L.J., Miller, N.J., Siegfried, B.D., Sappington, T.W., Robertson, H.M. 2023. A draft Diabrotica virgifera virgifera genome: insights into control and host plant adaption by a major maize pest insect. BMC Genomics. 24. Article 19. https://doi.org/10.1186/s12864-022-08990-y.
Corbett, S.M., Cullum, J.P., Abrams, A.E., Rodriguez, M.S., Leskey, T.C., Walse, S.S. 2023. Confirmatory evaluation of eFUME for control of brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae). Journal of Economic Entomology. 116(3):771-778. https://doi.org/10.1093/jee/toad064.
