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James D. Hansen, Dennis J. Albano, and Millie L. Heidt

The two-component quarantine treatment was shown to be effective against at least 7,000 codling moth (Cydia pomonella) fifth instar larvae infesting `Fuji' apples (Malus × domestica) in each required confirmation test involving two sizes of cartons. After cold storage for 55 days at 36 °F (2.2 °C), infested fruit were placed in vented cartons, either 20-lb [7 × 12 × 12.5 inches (17.8 × 30.5 × 31.8 cm)], or 40-lb [12 × 12.5 × 20.5 inches (30.5 × 31.8 × 52.1 cm)], then fumigated with 0.056 oz/ft3 (56 g·m-3) of methyl bromide for 2 hours at 50 °F (10.0 °C). After each treatment, either no survivors were present or no moribund larvae survived beyond the first week of post evaluation of the larvae.

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J.D. Hansen, M.L. Heidt, M.A. Watkins, S.R. Drake, J. Tang, and S. Wang

Quarantine regulations require domestic sweet cherries (Prunus avium) exported to Japan to be treated to control codling moth [Cydia pomonella (Lepidoptera: Tortricidae)]. The current procedure, methyl bromide fumigation, may be discontinued because of health, safety, and environmental concerns. To examine a potential alternative method, `Bing' sweet cherries were each infested with a codling moth larva, submerged in a 38 °C water bath for 6 minutes pretreatment, then exposed to various temperatures generated by radio frequency and held at that temperature for different times: 50 °C for 6 minutes, 51.6 °C for 4 minutes, 53.3 °C for 0.5 minutes, and 54.4 °C for 0.5 minutes. Insect mortality was evaluated 24 hours after treatment and fruit quality was evaluated after treatment and after 7 and 14 days of storage at 1 °C. No larvae survived at the 50 and 51.6 °C treatments. Fruit color of non-infested cherries was darkened as temperature increased. Stem color was severely impacted after 7 days of storage, even in a warm water bath of 38 °C for 6 minutes, as was fruit firmness at the same treatment. Fruit quality loss increased after 14 days of storage, compared to after 7 days of storage. The amount of pitting and bruising of cherries increased with temperature and again this increase was more evident after 14 days of storage.

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J.D. Hansen, M.L. Heidt, M.A. Watkins, S.R. Drake, J. Tang, and S. Wang

Efficacy of using radio frequency (RF) at 27.12 MHz was evaluated as a postharvest quarantine treatment against fifth instars of the codling moth [Cydia pomonella (Lepidoptera: Tortricidae)], in apples (Malus sylvestris). Tests under the given conditions demonstrated that the energy fields between the RF unit's electrodes were neither predictable nor uniform. Moving fruit submerged in water during RF exposure may improve uniformity, but pulp temperatures varied considerably among fruit, among sites on the same fruit, and at different depths within the same site. As a result of these inconsistencies, quarantine efficacy was not obtained either using a range of final average temperatures from 40 to 68 °C (104.0 to 154.4 °F) or at holding times up to 20 minutes. We concluded it would be difficult to obtain the appropriate parameters for treatment efficacy and fruit quality maintenance using this technology under these conditions.

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M. A. L. Smith, J. Reid, A. Hansen, Z. Li, and D. L. Madhavi

Industrial-scale cultivation of plant cells for valuable product recovery (e.g. natural pigments, pharmaceutical compounds) can only be considered commercially-feasible when a fully-automated, predictable bioprocess is achieved. Automation of cell selection, quantification, and sorting procedures, and pinpointing of optimal microenvironmental regimes can be approached via machine vision. Macroscopic staging of Ajuga reptans callus masses (ranging between 2-6 g FW) permitted simultaneous rapid capture of top and side views. Area data used in a linear regression model yielded a reliable, non-destructive estimate of fresh mass. Suspension culture images from the same cell line were microscopically imaged at 4x (with an inverted microscope). Using color machine vision, the HSI (hue-saturation-intensity) coordinates were used to successfully separate pigmented cells and aggregates from non-pigmented cells, aggregates, and background debris. Time-course sampling of a routine suspension culture consistently allowed pigmented cells to be detected, and intensity could be correlated with the degree of pigmentation as verified using spectrophotometer analysis of parallel samples.

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J.D. Hansen, M.A. Watkins, M.L. Heidt, and P.A. Anderson

Codling moth [Cydia pomonella (Lepidoptera: Tortricidae)], found in exported apples (Malus sylvestris), can disrupt international markets. Cold storage at 1.1 °C was examined for possible control of three physiological larval states in ‘Fuji’ apples: diapausing (overwintering), diapause-destined, and nondiapausing. All nondiapausing larvae were dead within 12 weeks, diapaused-destined larvae were controlled by the seventh week, yet more than half of the original populations of diapausing larvae were still alive after 11 weeks. Because the diapaused-destined larvae were younger than the nondiapausing larvae, they may have been more susceptible to cold. Because larvae normally diapause outside the fruit, cold storage would not be applicable for controlling larvae in this state.

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James D. Hansen, Stephen R. Drake, Harold R. Moffitt, Dennis J. Albano, and Millie L. Heidt

A quarantine treatment was developed against codling moth (Cydia pomonella L.) (Lepidoptera: Tortricidae) for the sweet cherry (Prunus avium L.) cultivars ('Garnet,' `Brooks,' `Tulare,' `Lapins,' and `Sweetheart') exported to Japan. Specific procedures were required to demonstrate treatment efficacy. Dose-mortality responses were measured for each cultivar at regularly incremented concentrations of methyl bromide for 2 hours at 43 °F (6 °C) compared to the dose-mortality curve of an approved cultivar under the same conditions. Based on the overlap of confidence limits, there were no significant differences between new and approved cultivars in group comparisons. In a confirmation test of efficacy, fumigation with methyl bromide at 0.064 oz/ft3 (64 g·m-3) for 2 hours at 43 °F resulted in complete mortality for all codling moth larvae in the treated cultivars. By convention, fumigation at this or the following concentrations [0.048 oz/ft3 (48 g·m-3) for 2 h at 54 to 63 °F (12 to 17 °C); 0.040 oz/ft3 (40 g·m-3) for 2 h at 63 to 72 °F (17 to 22 °C); 0.032 oz/ft3 (32 g·m-3) for 2 h at 72 °F (22 °C) or above] were considered as an efficacious quarantine treatment against the codling moth in sweet cherries. Except for `Brooks,' fumigation did not significantly influence fruit firmness, soluble solids, or titratable acids. Reduction in fruit and stem quality was more associated with temperature than with methyl bromide concentration. `Tulare,' `Lapins,' and `Sweetheart' could be fumigated with minimal change in fruit quality.

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James D. Hansen, Harold R. Moffitt, Dennis J. Albano, Millie L. Heidt, Stephen R. Drake, and Jacqueline L. Robertson

Confirmatory tests were performed on a two-component quarantine treatment against the codling moth (Cydia pomonella L.) (Lepidoptera: Tortricidae) for seven apple [Malus sylvestris (L.) var. domestica (Borkh.) Mansf.] cultivars ('Delicious,' `Golden Delicious,' `Braeburn,' `Fuji,' `Gala,' `Jonagold,' and `Granny Smith') intended for export to Japan and Korea. Treatment consists of a 55-day cold storage at 40 °F (2.2 °C) or below, followed by a 2-hour methyl bromide fumigation (0.056 oz/ft3 or 56 g·m-3) at 50 °F (10 °C). No eggs or larvae survived this treatment. Comparison tests were conducted on all cultivars to demonstrate no difference in insect responses between a previously accepted cultivar and proposed cultivars. Concentration-mortality responses were determined for each of the components and no statistical differences were found in the regression slopes of pest mortality with controlling variable (either cold exposure or fumigation) among all cultivars. Descriptive mathematical models, developed for the effects of cold storage on egg mortality and for methyl bromide fumigation on larvae mortality, were sigmoid curve equations.