Location: Crop Improvement and Protection Research
2016 Annual Report
Objectives
The long-term goal of this project is to develop alternative postharvest pest control treatments that are effective and safe for control of quarantine pests on a wide range of perishable agricultural commodities. This project builds upon our previous success with nitric oxide (NO) and oxygenated phoshine (PH3) fumigations as potential alternatives to methyl bromide fumigation for postharvest pest control on fresh fruits and vegetables. Nitric oxide was found to have higher efficacy than regular PH3 and may also enhance postharvest quality of fresh products. Oxygenated PH3 fumigation was found to control external pests with greater efficacy than regular PH3 fumigation. Successful completion of the project will result in specific NO fumigation and oxygenated PH3 fumigation treatments against four insect species on fresh fruit and vegetables including western flower thrips, light brown apple moth, codling moth, and the fruit fly spotted wing drosophila. Specific objectives are listed below:
Objective 1. Develop nitric oxide fumigation treatments for postharvest pest control.
Sub-objective 1.A. Develop an effective nitric oxide fumigation treatment to control western flower thrips on fresh fruit and vegetables.
Sub-objective 1.B. Develop an effective nitric oxide fumigation treatment to control light brown apple moth on fruit.
Sub-objective 1.C. Develop an effective nitric oxide fumigation treatment to control codling moth in apples.
Sub-objective 1.D. Develop an effective nitric oxide fumigation treatment to control spotted wing drosophila in sweet cherries and strawberries.
Objective 2. Develop oxygenated phosphine fumigation treatments for postharvest pest control.
Sub-objective 2.A. Determine feasibility of oxygenated phosphine fumigation to control codling moth in apples.
Sub-objective 2.B. Determine feasibility of oxygenated phosphine fumigation to control spotted wing drosophila in strawberries.
Approach
Objective 1. Nitric oxide fumigation under ultralow oxygen conditions will be studied for controlling insect pests including western flower thrips, light brown apple moth, codling moth, and spotted wing drosophila on harvested fresh commodities for their exports. Small scale laboratory fumigations will be conducted to determine effective treatments (concentration, time, and temperature) for different insects. Selected treatments will then be tested on specific fresh products to evaluate the impact of the treatments on postharvest quality.
Objective 2. Oxygenated phosphine fumigation under high oxygen conditions will be studied for controlling codling moth larvae in apples and spotted wing drosophila in sweet cherries and strawberries. Small scale laboratory fumigations will be conducted to determine effective treatments to control the most tolerant life stages of the pests in the fruits. Selected effective treatments will then be tested on fresh products to verify their efficacies and impact of postharvest quality of the fresh products.
Progress Report
This report documents progress for the parent project 2038-22430-002-00D, "Methyl Bromide Replacement: Post-harvest Treatment of Perishable Commodities," which started in October 2015 and continues research from project 2038-22430-001-00D, "Chemical Alternatives to Methyl Bromide for Post-Harvest Pest Control on Perishable Commodities."
Western flower thrips were successfully controlled with nitric oxide fumigation. A selected fumigation treatment was also tested on strawberries together with thrips. The treatment not only controlled thrips but also resulted in better strawberry quality preservation as compared with untreated controls for berry firmness and color.
Light brown apple moth eggs, larvae, and pupae on artificial diet were successfully controlled with nitric oxide fumigation treatments at a low storage temperature of 2° Celsius (C). The treatment time ranged from eight hours to 48 hours depending on nitric oxide concentration and life stages. Successful control of codling moth eggs and larvae on artificial diet was achieved in apple. Infested apples containing medium and large larvae were fumigated with nitric oxide at 3% and 5% for 24 hours at 2°C. Complete control was achieved with the 5% nitric oxide fumigation. Preliminary tests showed that the treatment for codling moth control not only did not have any negative impact on apple quality but also resulted in higher firmness of apple flesh than the controls. Additionally, research was initiated to determine residues from nitric oxide fumigation in fresh products to prepare for future registration of nitric oxide for postharvest pest control applications.
Accomplishments
1. Nitric oxide fumigation treatment for control of light brown apple moth (LBAN). An ARS researcher in Salinas, California successfully controlled light brown apple moth with nitric oxide fumigation. Nitric oxide is a new fumigant discovered at USDA-ARS and is effective against a wide variety of pests. Light brown apple moth is quarantined in most countries and an effective treatment is needed to facilitate exports of U.S. fresh products. Nitric oxide fumigation under ultralow oxygen conditions achieved complete control of light brown apple moth eggs, larvae, and pupae at a low cold storage temperature in 6 to 48 h depending on nitric oxide concentrations. The study demonstrates the great potential of nitric oxide fumigation in controlling postharvest pests including light brown apple moth on exported fresh products.
2. Bed bug control using ultralow oxygen and vacuum treatments. An ARS researcher in Salinas, California in collaboration with an entomologist from the University of Kentucky developed effective bed bug treatments for removable objects using ultralow oxygen (ULO) atmosphere and vacuum. Complete control of bed bug nymphs and adults and almost complete control of eggs were achieved in 8 hours with 0.1% oxygen atmosphere at 30C. Complete control of all life stages was achieved in 12 hours under vacuum at 30°C. The study demonstrated that ULO and vacuum have the potential to be used as effective and safe treatments to decontaminate bed bug infested removable objects.
None.
Review Publications
Liu, Y.-B. 2015. Nitric oxide as a fumigant for postharvest pest control and its safety to postharvest quality of fresh products. Acta Horticulturae. 1101:321-327.
Liu, Y.-B., Haynes, K.F. 2016. Effects of ultralow oxygen and vacuum treatments on bed bug (Heteroptera: Cimicidae) survival. Journal of Economic Entomology. 109:1303-1309.
