Location: Tropical Crop and Commodity Protection Research
2017 Annual Report
Objectives
The long-term goals of our research program are to develop and protect U.S. export markets for fresh tropical commodities. An emphasis is placed on expanding and diversifying agriculture and agricultural exports in Hawaii and other states by providing environmentally sound, economically viable systems, treatments, or processes that control quarantine pests, ensure product quality, and increase product value while safeguarding the agriculture of other states. Our research will address four broad objectives over the next 5 years:
Objective 1: Develop new or improved postharvest treatments or technologies for fresh tropical commodities to ensure security against quarantine pests, including new irradiation treatments for western flower thrips, and various ants on fresh fruits.
Sub-objective 1A. Develop quarantine irradiation treatments for western flower thrips, coffee berry borer, rough sweetpotato weevil, and red imported fire ant.
Sub-objective 1B. Develop a quarantine cold treatment for melon fly in citrus.
Sub-objective 1C. Determine the effectiveness of hypobaric treatments against surface pests.
Objective 2: Develop new or improved postharvest treatments or systems (such as hypobaric storage and modified atmospheres) to improve quality and extend shelf life of tropical horticultural crops subjected to quarantine treatment.
Sub-objective 2A. Determine hypobaric storage conditions that retain quality and extend storage life of fresh tropical fruit.
Sub-objective 2B. Develop combination treatments of modified atmosphere packaging and irradiation to retain quality of exported fresh papaya.
Objective 3: Develop or improve preharvest methods for surveillance, detection, and control of invasive tropical plant pests of quarantine significance, such as coffee berry borer.
Sub-objective 3A. Study the ecology of Cathartus quadricollis and other predatory flat bark beetles and explore ways to increase their role in suppressing coffee berry borer populations in coffee.
Objective 4: Develop multiple-component systems approaches to decrease the severity of or need for commodity treatments.
Sub-objective 4A. Quantify systems approaches for quarantine security of melon fly.
Approach
The approach is to develop quarantine treatments, such as low dose irradiation and hypobaric treatments, and other mitigation techniques for fresh tropical commodities and ornamental crops. Quarantine irradiation treatment will be developed for rough sweetpotato weevil, in sweet potato, western flower thrips, red imported fire ant, and coffee berry borer. Optimum hypobaric treatment parameters for maritime shipment of tropical fruits to preserve quality and extend shelf life will be determined. We will establish the tolerance of tropical fruits to any new or modified quarantine treatments.To expand markets for high-value tropical specialty fruit, we will develop postharvest disease and packaging strategies to extend shelf life. Integrated pest management strategies for coffee berry borer will focus on understanding the population dynamics and ecology of predatory flat bark beetles and improving rear-and-release systems. A cold treatment will be developed for melon fly in citrus. Also, a systems approach will be developed for melon fly control in covered tomatoes using mass trapping, protein baits and sanitation.
Progress Report
This research project develops pre-harvest and postharvest treatments or systems to control quarantine pests, while retaining the quality and shelf-life of tropical crops. The project supports the expansion and diversification of U.S. exports of fresh tropical crops, while protecting U.S. agriculture from pest incursions.
Proposed irradiation quarantine treatments were submitted to the International Plant Protection Convention Technical Panel for Phytosanitary treatments for several important U.S. pests and pest groups including spotted wing drosophila, 100 Gray (Gy), light brown apple moth, 200 Gy, eggs and larvae, moths in the family Tortricidae, 250 Gy eggs and larvae, ants ,100 Gy, European grapevine moth, 250 Gy, oriental fruit fly, 125 Gy, coffee berry borer, 100 Gy, Western flower thrips, 250 Gy, and beetles in the Curculionidae, 150 Gy, to obtain internationally approved treatments. A proposed irradiation treatment for Tortricidae eggs and larvae was approved and added to the USDA Treatment Manual.
A thyme and oregano oil extract was shown to provide synergistic control of rice weevil, and Aspergillus and Penicillium molds in packaged rice.
Novel breeding stations developed with the company, Alpha Scents, are now commercially available as a way to augment numbers of Cathartus quadricollis, a predator of the coffee pest coffee berry borer. Coffee growers are also independently raising and releasing the predatory beetles on their farms.
Attractant and deterrent/repellent bioassays were developed to identify recruitment pheromones and deterrent chemicals for little fire ant management.
In postharvest quality research, the differential tolerance of apple cultivars to potential x-ray disinfestation for codling moth showed that ‘Royal Gala’ was the most susceptible cultivar, with increased internal browning as dose increased above 500 Gy.
The storage life for mango fruit was extended by 7-10 days under hypobaric conditions (2.7 kilopascal, 13 degrees Celsius) when compared to control fruit. Fruit ripened normally after removal from hypobaric storage, however postharvest diseases limited the shelf-life of control and treated mangos equally.
Accomplishments
1. Novel breeding station for coffee berry borer predator (CBB). CBB is a serious pest of coffee worldwide and a new invasive pest in Hawaii. Flat bark beetle predators such as Cathartus quadricollis are the most significant natural enemies, but only feed on CBB in dried berries on the tree. C. quadricollis, also known as the square necked grain beetle, is a stored product pest and easily raised on corn. ARS scientists in Hilo, Hawaii, with researchers from Alpha Scents, developed novel breeding stations consisting of a screened plastic container with a pheromone lure (attractant) and cracked corn (food) to encourage reproduction in the coffee farm at times when infested dried cherries are scarce. The stations and lures are commercially available through Alpha Scents, which is funding ARS to conduct field studies on optimal deployment strategies.
2. Improved lure for spotted wing drosophila (SWD). SWD is a serious pest of berries and cherries in the U.S. and Europe. Currently two commercial lures (Scentry and Trece), using four chemicals from wine and vinegar are widely used to detect, monitor and control SWD. ARS scientists in Hilo, Hawaii, conducted a series of experiments varying the levels and release rates of the four chemicals in the existing lures to optimize the concentrations of each for attracting SWD. A new lure was developed that is 2-fold more attractive than the existing lures. The new more potent SWD lure will improve SWD management programs by providing better detection of smaller populations and detection of populations earlier in the season, as well as improving attract-and-kill technology.
3. Quarantine treatment for fresh apple cultivars. Disinfestation of fresh commodities with X-ray radiation is an effective and accepted quarantine treatment for export markets. ARS scientists in Hilo, Hawaii, collaborated scientists at the New Zealand Institute of Plant and Food Research to determine the tolerance of four apple varieties to ionizing radiation in a commercial facility. All cultivars but ‘Royal Gala’ maintained quality following treatment at doses effective for controlling codling moth and other insect pests. The results will support adoption of x-ray quarantine treatment by the New Zealand apple industry.
Review Publications
Cuezzo, F., Calcaterra, L., Chifflet, L., Follett, P.A. 2015. Wasmannia Forel(Hymenoptera: Formicidae: Myrmicinae) in Argentina: systematics and distribution. Sociobiology. 62:246-265.
Downey, D., Chun, S., Follett, P.A. 2015. Radiobiology of Aethina tumida and prospects for management using sterile insect releases. Journal of Economic Entomology. 108(3):868-872.
Cha, D.H., Adams, T., Landolt, P.J. 2017. Effect of chemical ratios of a microbial-based feeding attractant on trap catch of spotted wing drosophila (Diptera: Drosophilidae). Environmental Entomology. 46(4):907-915.
Wallingford, A.K., Cha, D.H., Loeb, G.M. 2017. Evaluating a push-pull strategy for management of Drosophila suzukii Matsumura in red raspberry. Pest Management Science. doi: 10.1002/ps.4666
Cha, D., Olsson, S., Yee, W.L., Goughnour, R., Hood, G., Mattsson, M., Schwarz, D., Feder, J., Linn, C. 2017. Identification of host fruit volatiles from snowberry (Symphoricarpos albus), attractive to Rhagoletis zephyria flies from Western United States. Journal of Chemical Ecology. 43(2):188-197.
