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Brown SDJ, Bellvé AM, Santos K, Baldassarre CE, Mansfield E, Bilgi V, Urlacher EMG, Devitt JC, Jamieson LE. An 18-day, 3 °C cold treatment effectively kills Ceratitis capitata (Diptera: Tephritidae) in kiwifruit (Actinidia spp.). J Econ Entomol 2024; 117:480-493. [PMID: 38262450 PMCID: PMC11011633 DOI: 10.1093/jee/toad242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/05/2023] [Accepted: 12/19/2023] [Indexed: 01/25/2024]
Abstract
A series of experiments were carried out to develop a phytosanitary disinfestation protocol to kill Ceratitis capitata (Weidemann) (Mediterranean fruit fly, Diptera: Tephritidae) in 'Hayward' kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang and A.R. Ferguson) and 'Zesy002' kiwifruit (Actinidia chinensis Planch.). Experiments on 4 immature life stages (eggs and 3 larval instars) with treatment durations of between 5 and 18 days showed that third instars were the most tolerant to temperatures around 3 °C, with the lethal time to 99.9968% (probit 9) mortality (LT99.9968) estimated to be 17.3 days (95% confidence interval (CI) 16.4-18.2). Larvae reared and treated in 'Zesy002' were significantly more susceptible to cold treatment than those reared in 'Hayward'. A large-scale trial testing a disinfestation protocol of 3 ± 0.5 °C for 18 days treated over 500,000 third-instar C. capitata with no survivors. These results demonstrate that a cold treatment of 3.5 °C or below for 18 days induces C. capitata mortality in kiwifruit at a rate that exceeds 99.9968% with a degree of confidence greater than 99%.
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Affiliation(s)
- Samuel D J Brown
- The New Zealand Institute for Plant and Food Research Limited, Mount Albert Research Centre, Auckland, New Zealand
| | - André M Bellvé
- The New Zealand Institute for Plant and Food Research Limited, Mount Albert Research Centre, Auckland, New Zealand
| | - Karina Santos
- The New Zealand Institute for Plant and Food Research Limited, Mount Albert Research Centre, Auckland, New Zealand
| | - Cristian E Baldassarre
- The New Zealand Institute for Plant and Food Research Limited, Mount Albert Research Centre, Auckland, New Zealand
| | - Emma Mansfield
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Vineeta Bilgi
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | | | - Jessica C Devitt
- Ministry for Primary Industries Manatū Ahu Matua, Wellington, New Zealand
| | - Lisa E Jamieson
- The New Zealand Institute for Plant and Food Research Limited, Mount Albert Research Centre, Auckland, New Zealand
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Tubby K, Forster J, Mullett M, Needham R, Smith O, Snowden J, McCartan S. Can the Seed Trade Provide a Potential Pathway for the Global Distribution of Foliar Pathogens? An Investigation into the Use of Heat Treatments to Reduce Risk of Dothistroma septosporum Transmission via Seed Stock. J Fungi (Basel) 2023; 9:1190. [PMID: 38132790 PMCID: PMC10744699 DOI: 10.3390/jof9121190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/04/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023] Open
Abstract
The international plant trade results in the accidental movement of invasive pests and pathogens, and has contributed significantly to recent range expansion of pathogens including Dothistroma septosporum. Seeds are usually thought to present a lower biosecurity risk than plants, but the importation of Pinus contorta seeds from North America to Britain in the mid-1900s, and similarities between British and Canadian D. septosporum populations suggests seeds could be a pathway. Dothistroma septosporum has not been isolated from seeds, but inadequately cleaned seed material could contain infected needle fragments. This case study investigated whether cone kilning, and wet and dry heat treatments could reduce D. septosporum transmission without damaging seed viability. Pinus needles infected with D. septosporum were incubated alongside cones undergoing three commercial seed extraction processes. Additional needles were exposed to temperatures ranging from 10 to 67 °C dry heat for up to 48 h, or incubated in water heated to between 20 and 60 °C for up to one hour. Pinus sylvestris seeds were exposed to 60 and 65 dry heat °C for 48 h, and further seed samples incubated in water heated to between 20 and 60 °C for up to one hour. Dothistroma septosporum survived the three kilning processes and while seeds were not damaged by dry heat exceeding 63.5 °C, at this temperature no D. septosporum survived. Wet heat treatments resulted in less than 10% pathogen survival following incubation at 40 °C, while at this temperature the seeds suffered no significant impacts, even when submerged for one hour. Thus, commercial seed kilning could allow D. septosporum transmission, but elevated wet and dry heat treatments could be applied to seed stock to minimise pathogen risk without significantly damaging seed viability.
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Affiliation(s)
- Katherine Tubby
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
| | - Jack Forster
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
| | - Martin Mullett
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
- Department of Forest Protection and Wildlife Management, Faculty of Forestry and Wood Technology, Phytophthora Research Centre, Mendel University in Brno, Zemědělská 3, 613 00 Brno, Czech Republic
| | - Robert Needham
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
| | - Olivia Smith
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
| | - James Snowden
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
| | - Shelagh McCartan
- Forest Research, Forestry Commission, Alice Holt Lodge, Farnham GU10 4LH, UK (M.M.); (O.S.); (J.S.); (S.M.)
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Wright C, Wyatt P, Mayer D, Leach P. Improved statistical methods for estimating infestation rates in quarantine research when hosts are naturally infested. J Econ Entomol 2023; 116:1990-1997. [PMID: 37904594 PMCID: PMC10711534 DOI: 10.1093/jee/toad203] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/09/2023] [Accepted: 10/16/2023] [Indexed: 11/01/2023]
Abstract
Trading partners often require phytosanitary or quarantine treatments for fresh horticultural produce to ensure no economically important pest species are moved with the imported product. When developing such treatments, it is essential that the level of treatment efficacy can be determined. This is often based on the mortality of the total number of target pests exposed to treatment, but in naturally infested products this number is not always known. In such cases, the infestation rate and subsequently an estimate of the number of pests are obtained directly from a set of untreated control samples of the host product. The International Plant Protection Convention (IPPC) Secretariat has provided 2 formulas for these situations that place an interval around the point estimate obtained from the control samples to obtain an estimate of the infestation rate. However, these formulas do not allow a confidence level to be assigned to the estimate, and there are concerns with the assumptions regarding the distribution and the measure of variability used in the formulas. In this article, we propose 2 alternative formulas. We propose that the lower one-sided confidence limit should be applied to all infestation datasets that are approximately normally distributed. As infestation data are sometimes skewed, it is proposed the lower one-sided modified Cox confidence limit is applied to data approximately log-normal distributed. These well-recognized formulas are compared to the formulas recommended by the IPPC and applied to 3 datasets involving natural infestation.
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Affiliation(s)
- Carole Wright
- Department of Agriculture and Fisheries, Mareeba, QLD 4880, Australia
| | - Pauline Wyatt
- Department of Agriculture and Fisheries, Ecosciences Precinct, Dutton Park, QLD 4102, Australia
| | - David Mayer
- Department of Agriculture and Fisheries, Ecosciences Precinct, Dutton Park, QLD 4102, Australia
| | - Peter Leach
- Department of Agriculture and Fisheries, Cairns, QLD 4870, Australia
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Corbett SMA, Cullum JP, Abrams AE, Rodriguez MS, Leskey TC, Walse SS. Confirmatory evaluation of eFUME for control of brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae). J Econ Entomol 2023:7159927. [PMID: 37165837 DOI: 10.1093/jee/toad064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 02/10/2023] [Accepted: 04/17/2023] [Indexed: 05/12/2023]
Abstract
The governments of Australia and New Zealand require a phytosanitary treatment to control adult brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), as overwintering aggregations have been intercepted in the importation pathway of various nonhorticultural consignments, including vehicles. The commercialized fumigant, eFUME, a 16.7% by mass dilution of ethyl formate in carbon dioxide, resulted in complete control of ca. 1,000 field-collected, naturally diapausing adult H. halys in each of 3 independent trials at 10 ± 0.5 °C (x¯ ± 2s) when ethyl formate levels in enclosure headspace were maintained steady-state at ca. 14.5 mg/liter for 4 h to yield Ct exposures ranging from 57.9 to 63.1 mg/liter h. Consistent with previous findings where greenhouse reared H. halys were controlled using laboratory formulations of this ethyl formate-carbon dioxide mixture, these confirmatory methods and results further inform technical and operational features of commercial practice.
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Affiliation(s)
- Stephen M A Corbett
- USDA-Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648, USA
- Agricultural and Environmental Chemistry Graduate Group, Department of Environmental Toxicology, University of California at Davis, 4117 Meyer Hall, Davis, CA, 95616, USA
| | - John P Cullum
- USDA-Agricultural Research Service, Appalachian Fruit Research Station, 2217 Wiltshire Road, Kearneysville, WV 25430, USA
| | - Adelaine E Abrams
- Horticulture and Agronomy Graduate Group, University of California at Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Mathew S Rodriguez
- USDA-Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648, USA
| | - Tracy C Leskey
- USDA-Agricultural Research Service, Appalachian Fruit Research Station, 2217 Wiltshire Road, Kearneysville, WV 25430, USA
| | - Spencer S Walse
- USDA-Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648, USA
- Agricultural and Environmental Chemistry Graduate Group, Department of Environmental Toxicology, University of California at Davis, 4117 Meyer Hall, Davis, CA, 95616, USA
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Hall MKD, Adlam AR. Comparison between the penetration characteristics of methyl bromide and ethanedinitrile through the bark of pine (Pinus radiata D.Don) logs. Pest Manag Sci 2023; 79:1442-1451. [PMID: 36495484 DOI: 10.1002/ps.7316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 11/28/2022] [Accepted: 12/10/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Ethanedinitrile (EDN) is a fumigant being commercialized worldwide as an alternative phytosanitary treatment to methyl bromide (MB) for forest products. The penetration characteristics of MB and EDN were measured through the bark of wooden blocks (100 × 100 × 50 mm) cut from the upper (average bark thickness 5 ± 2 mm) and lower (average bark thickness 25 ± 5 mm) trunk of recently felled pine (Pinus radiata D.Don) trees. Doses of 48 g m-3 MB and 50 g m-3 EDN were applied to chambers at 10 and 20°C for 10 h. RESULTS Penetration of MB was influenced by the interaction between fumigation time and temperature, with concentrations increasing at a higher rate at 20°C compared with at 10°C. After 10 h, an average concentration of 8.05 ± 0.89 g m-3 had penetrated the bark of log sections at 20°C, whereas 5.20 ± 0.89 g m-3 was measured at 10°C. By contrast, the factors examined in this study did not significantly impact the penetration of EDN. Concentration × time (CT) values for MB under the bark were 35.20 ± 2.30 g h m-3 at 10°C and 55.85 ± 9.58 g h m-3 at 20°C; whereas for EDN, CT values were 19.50 ± 6.80 g h m-3 at 10°C and 19.08 ± 4.10 g h m-3 at 20°C. CONCLUSION MB can achieve a higher concentration under the bark of log sections during simulated fumigations, but all of the factors examined affected the ability of MB to penetrate the bark of wooden blocks. By comparison, the penetration of EDN through the bark is more consistent than MB under laboratory conditions. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Matthew K D Hall
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
- Draslovka Services, North Melbourne, VIC, Australia
| | - Anthony R Adlam
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
- Genera Science & Innovation, Mount Maunganui, New Zealand
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Buddenhagen CE, Hackell D, Henderson HV, Wynne‐Jones B. Factors impacting the detection of weed seed contaminants in seed lots. Pest Manag Sci 2023; 79:881-890. [PMID: 36308732 PMCID: PMC10099985 DOI: 10.1002/ps.7257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/18/2022] [Accepted: 10/29/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND The setting and following of phytosanitary standards for weed seeds can lessen the impacts of weeds on agriculture. Standards adopted by seed companies, laboratories and regulators ensure the contamination rates do not exceed some thresholds. Globally sample size standards are set based on the amount needed to obtain a contaminant in a random sample of the seed lot, not detectability. New Zealand requires a 95% confidence that the maximum pest limit of 0.01% of quarantine weed seed contamination is not exceeded in an imported seed lot. We examined 24 samples each containing approximately 150 000 seeds of either perennial ryegrass (12 samples) or white clover seeds (12 samples) that were then spiked with seeds (contaminants) from 12 non-crop species (3-8 seeds of each). We considered factors that may impact detection rates: shape, color, size, and texture relative to the crop, and technician (including a commercial seed laboratory). RESULTS A linear mixed model fitted to the data indicated significant observer, crop, and seed color, shape, and size effects on detection. Detectability increased by 20% ± 7.7 (± standard error) when seeds had a distinct shape or color (28% ± 8.1), or were larger (23% ± 8.7) rather than smaller, relative to the crop. Commercial laboratory identifications were usually correct at the level of genus, and species for common weeds, but some misidentifications occurred. CONCLUSION Sample sizes for border inspections should be based on detectability of regulated weed seeds in the crop in combination with weed risk for the crop and location. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Follett PA, Asmus G, Hamilton L, Stockton D. Susceptibility of 'Malama' Avocados to Bactrocera dorsalis (Diptera: Tephritidae) in Hawai'i and a Proposed Systems Approach for Market Access. J Econ Entomol 2022; 115:1894-1900. [PMID: 36271840 DOI: 10.1093/jee/toac150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Indexed: 06/16/2023]
Abstract
Avocados are generally poor hosts or nonhosts for tephritid fruit flies, which can influence the type of mitigation measures required by export protocols for trade. We conducted experiments to determine the susceptibility of the avocado, Persea americana, cv. 'Malama' to infestation by Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), in Hawai'i using laboratory and field no-choice cage tests, together with field sampling. In no-choice cage tests, infestation rates increased with decreasing fruit firmness over time after harvest. Although risk of infestation was negatively correlated with fruit firmness, about 50% of mature hard fruit exposed immediately after harvest became infested. In field cage tests, mature hard fruit on the tree at the 25% purple color stage were not infested, whereas fruit at the 50, 75, and 100% purple color stages were infested at relatively low rates. Field sampling of fallen 'Malama' fruit over two seasons showed no natural infestation by B. dorsalis and trap captures in avocado orchards using McPhail traps containing protein bait lures averaged 0.13 ± 0.03 (mean ± SE) flies per trap per week, underscoring the low prevalence of fruit flies in avocado orchards and the poor host quality of this cultivar. A systems approach based on poor host status, low prevalence, and a limited harvest period (October to March) and distribution area (northern tier states) is proposed to export 'Malama' avocados from Hawai'i to the continental United States.
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Affiliation(s)
- Peter A Follett
- USDA-ARS, Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center, 64 Nowelo Street, Hilo, HI, USA
| | - Glenn Asmus
- USDA-ARS, Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center, 64 Nowelo Street, Hilo, HI, USA
| | - Lindsey Hamilton
- USDA-ARS, Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center, 64 Nowelo Street, Hilo, HI, USA
| | - Dara Stockton
- USDA-ARS, Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center, 64 Nowelo Street, Hilo, HI, USA
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Follett P, Hamilton L, Tagami Y, Kaluna L, Jarvi S. Phytosanitary irradiation using X-rays prevents reproduction in the semi-slug Parmarion martensi (Stylommatophora: Ariophantidae), a host of the human pathogenic nematode Angiostrongylus cantonensis (Rhabditida: Angiostrongylidae). Pest Manag Sci 2022; 78:1187-1193. [PMID: 34821013 PMCID: PMC9299610 DOI: 10.1002/ps.6735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/21/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Phytosanitary irradiation is used to control insect pests of quarantine concern on exported fresh horticultural products. Generic irradiation doses of 150 and 400 Gy are approved for tephritid fruit flies and all other insects, respectively. Other invertebrates such as gastropods (snails and slugs) may be classified as quarantine pests and require a disinfestation treatment. Parmarion martensi Simroth (Stylommatophora: Ariophantidae) is a semi-slug quarantine pest sometimes found on fresh sweet potatoes and other fruits and vegetables exported from Hawai'i to the continental USA. Also, P. martensi is a host of the parasitic nematode Angiostrongylus cantonensis (Rhabditida: Angiostrongylidae), the causative agent of neuroangiostrongyliasis or rat lungworm disease in humans. We conducted a study to determine if phytosanitary irradiation could control P. martensi and thereby reduce the risk of transmitting A. cantonensis in the USA. RESULTS Two-, 12-, and 21-week-old P. martensi were treated with X-ray radiation at a dose of 150 or 400 Gy or left untreated as controls then held in the laboratory for up to 250 days. Survivorship and reproduction were recorded every 2-3 days and individual weights were measured biweekly. Irradiation at 150 and 400 Gy reduced growth and increased the mortality rate compared to untreated controls and prevented reproduction. CONCLUSION Phytosanitary irradiation treatment at doses ≥150 Gy will prevent the establishment of viable populations of P. martensi. The literature on radiation tolerance in gastropods suggests that the internationally approved generic dose for tephritid fruit flies of 150 Gy may be effective against many slug and snail pest species.
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Affiliation(s)
- Peter Follett
- USDA‐ARS, Daniel K. Inouye US Pacific Basin Agricultural Research CenterHiloHIUSA
| | - Lindsey Hamilton
- USDA‐ARS, Daniel K. Inouye US Pacific Basin Agricultural Research CenterHiloHIUSA
| | - Yaeko Tagami
- University of Hawai'i at Hilo, Daniel K. Inouye College of PharmacyHiloHIUSA
| | - Lisa Kaluna
- University of Hawai'i at Hilo, Daniel K. Inouye College of PharmacyHiloHIUSA
| | - Susan Jarvi
- University of Hawai'i at Hilo, Daniel K. Inouye College of PharmacyHiloHIUSA
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Mwando NL, Ndlela S, Meyhöfer R, Subramanian S, Mohamed SA. Hot Water Treatment for Post-Harvest Disinfestation of Bactrocera dorsalis (Diptera: Tephritidae) and Its Effect on cv. Tommy Atkins Mango. Insects 2021; 12:1070. [PMID: 34940157 DOI: 10.3390/insects12121070] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 11/17/2022]
Abstract
Simple Summary The oriental fruit fly Bactrocera dorsalis is a major quarantine pest in sub-Saharan Africa that threatens mango production and international trade. In this study, we developed a hot water treatment (HWT) protocol for the post-harvest disinfestation of B. dorsalis and assessed its impact on cv. Tommy Atkins mango quality parameters after treatment. First, we established the rate of development of the immature stages of B. dorsalis in cv. Tommy Atkins mango and then determined their heat tolerance. The third-instar larva was found to be the most heat tolerant of the immature stages. The study demonstrates that a hot water treatment schedule of 46.1 °C for 72.63 min can lead to complete mortality of the most heat-tolerant stage of B. dorsalis in cv. Tommy Atkins mango. Furthermore, we carried out large-scale confirmatory trials to validate our hot water treatment schedule, and none of the 59,120 most heat-tolerant larvae treated survived. Our protocol guarantees effective quarantine security with no adverse effect on the quality of cv. Tommy Atkins mango fruit and can be commercially adopted to promote and increase mango exports to lucrative markets abroad. Abstract Mango production and trade in sub-Saharan Africa is hampered by direct damage and the high quarantine status of B. dorsalis and the paucity of effective post-harvest phytosanitary treatments. The current study reports the development of a quarantine treatment protocol using hot water to disinfest B. dorsalis and assess its effect on cv. Tommy Atkins mango quality. We first determined the development of the eggs and all larval stages of B. dorsalis in cv. Tommy Atkins mango and used the information to establish a time–mortality relationship of the immature stages after subjecting infested fruits to a regimen of eight, time instances of hot water at 46.1 °C. Using probit analysis, we estimated the minimum time required to achieve 99.9968% mortality of each stage. Our results indicate that the egg was the least heat tolerant, followed by the first, second, and third instar. The time required to achieve 99.9968% control of the third instar in cv. Tommy Atkins mango (400–600 g) was determined to be 72.63 min (95% Cl: 70.32–74.95). In the confirmatory trials, the hot water treatment schedule of 46.1 °C/72.63 min was validated, and none of the 59,120 most heat-tolerant individuals treated survived. Further, there were no significant differences between hot water-treated and untreated mangoes recorded in weight loss, fruit firmness, pH, total soluble solids, moisture content, and titratable acidity eleven days post-treatment. These findings demonstrate an effectively optimum post-harvest disinfestation treatment against B. dorsalis in cv. Tommy Atkins mango that should be adopted commercially to facilitate access to profitable but strict export markets globally.
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Whattam M, Dinsdale A, Elliott CE. Evolution of Plant Virus Diagnostics Used in Australian Post Entry Quarantine. Plants (Basel) 2021; 10:1430. [PMID: 34371633 DOI: 10.3390/plants10071430] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/02/2021] [Accepted: 07/08/2021] [Indexed: 11/17/2022]
Abstract
As part of a special edition for MDPI on plant virology in Australia, this review provides a brief high-level overview on the evolution of diagnostic techniques used in Australian government Post-Entry Quarantine (PEQ) facilities for testing imported plants for viruses. A comprehensive range of traditional and modern diagnostic approaches have historically been employed in PEQ facilities using bioassays, serological, and molecular techniques. Whilst these techniques have been effective, they are time consuming, resource intensive and expensive. The review highlights the importance of ensuring the best available science and diagnostic developments are constantly tested, evaluated, and implemented by regulators to ensure primary producers have rapid and safe access to new genetics to remain productive, sustainable and competitive.
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Abstract
Tephritid fruit flies are major economic pests for fruit production and are an impediment to international trade. Different host fruits are known to vary in their suitability for fruit flies to complete their life cycle. Currently, international regulatory standards that define the likely legal host status for tephritid fruit flies categorize fruits as a natural host, a conditional host, or a nonhost. For those fruits that are natural or conditional hosts, infestation rate can vary as a spectrum ranging from highly attractive fruits supporting large numbers of fruit flies to very poor hosts supporting low numbers. Here, we propose a Host Suitability Index (HSI), which divides the host status of natural and conditional hosts into five categories based on the log infestation rate (number of flies per kilogram of fruit) ranging from very poor (<0.1), poor (0.1-1.0), moderately good (1.0-10.0), good (10-100), and very good (>100). Infestation rates may be determined by field sampling or cage infestation studies. We illustrate the concept of this index using 21 papers that examine the host status of fruits in five species of polyphagous fruit flies in the Pacific region: Bactrocera tryoni Froggatt, Bactrocera dorsalis (Hendel), Bactrocera latifrons (Hendel), Zeugodacus cucurbitae (Coquillett), and Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). This general-purpose index may be useful in developing systems approaches that rely on poor host status, for determining surveillance and detection protocols for potential incursions, and to guide the appropriate regulatory response during fruit fly outbreaks.
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Affiliation(s)
- Peter A Follett
- USDA ARS, Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center, Hilo, HI, USA
| | - Fay E M Haynes
- NSW Department of Primary Industries, The Ian Armstrong Building, Orange, NSW, Australia
| | - Bernard C Dominiak
- NSW Department of Primary Industries, The Ian Armstrong Building, Orange, NSW, Australia
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Navarro-Triviño FJ, Linares-González L, Llamas-Molina JM, Ruiz-Villaverde R. Airborne allergic contact dermatitis caused by spirotetramat (Movento 150®). Contact Dermatitis 2021; 85:99-100. [PMID: 33484163 DOI: 10.1111/cod.13793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/16/2021] [Accepted: 01/19/2021] [Indexed: 01/19/2023]
Affiliation(s)
- Francisco J Navarro-Triviño
- Department of Contact Eczema and Immunoallergic Diseases, Dermatology, Hospital Universitario San Cecilio, Granada, Spain
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Macquarrie CJK, Gray M, Lavallée R, Noseworthy MK, Savard M, Humble LM. Assessment of the Systems Approach for the Phytosanitary Treatment of Wood Infested With Wood-Boring Insects. J Econ Entomol 2020; 113:679-694. [PMID: 31844898 DOI: 10.1093/jee/toz331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Indexed: 06/10/2023]
Abstract
Addressing the risk from pests present in wood and wood products destined for international trade is an essential step towards minimizing the movement, introduction and establishment of invasive species. One method of managing the pest risk associated with wood commodities is the use of a systems approach that incorporates multiple independent measures applied along a production pathway. However, quantifying the reduction of risk can be difficult because the approach requires raw material infested with the pest of interest at a sufficient density to be able to quantify changes in pest abundance. We tested a systems approach for the production of sawn wood using green ash, Fraxinus pennsylvanica Marshall (Lamiales: Oleaceae), infested with emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), by quantifying the change in pest density during the milling process and the precise effect of heat treatment on insects in situ. Greater than 90% of emerald ash borer were removed at the first step of the milling process (debarking) and >99% were removed before the production of green sawn wood. No insects survived kilning or heat treatment. All life stages of emerald ash borer were killed at 56°C and above. Heat, however, had no sublethal effect on emerald ash borer performance. These results show that the application of a systems approach to mitigate emerald ash borer in heat-treated, sawn wood is effective. Moreover, the model-system approach developed in this study can be a template for investigating the effect of systems approaches for other phloem-feeding insects.
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Affiliation(s)
- Chris J K Macquarrie
- Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste. Marie, Ontario, Canada
| | - Meghan Gray
- Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste. Marie, Ontario, Canada
| | - Robert Lavallée
- Natural Resources Canada Canadian Forest Service, Laurentian Forestry Centre, Stn. Sainte-Foy, Québec, Quebec, Canada
| | - Meghan K Noseworthy
- Natural Resources Canada Canadian Forest Service, Pacific Forestry Centre, Victoria, British Columbia, Canada
| | | | - Leland M Humble
- Natural Resources Canada Canadian Forest Service, Pacific Forestry Centre, Victoria, British Columbia, Canada
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Shamoun SF, Hammett C, Sumampong G, Li X, Garbelotto M. New Taxon-Specific Heterobasidion PCR Primers Detect and Differentiate North American Heterobasidion spp. in Various Substrates and Led to the Discovery of Heterobasidion irregulare in British Columbia, Canada. Pathogens 2019; 8:E156. [PMID: 31540403 DOI: 10.3390/pathogens8030156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/10/2019] [Accepted: 09/13/2019] [Indexed: 11/16/2022] Open
Abstract
Heterobasidion annosum sensu lato is a species complex of pathogenic white-rot wood decay fungi which cause root and butt rot in conifer and hardwood species across the Northern hemisphere. Annual losses to forest managers are valued in the billions of dollars, due to tree mortality, reduction in timber yield, and wood decay. In North America, H. irregulare and H. occidentale have a partially overlapping host and geographic range, cause similar disease symptoms and produce similar fruiting bodies, making discrimination between the two of them often difficult. We developed two sets of primers that bind specifically to conserved, but species-specific portions of glyceraldehyde 3-phosphate dehydrogenase and elongation factor 1α alleles. The method is sensitive enough to detect either species from infected wood. Analysis of North American isolates has further clarified the distribution of both species on this continent, including the detection of H. irregulare for the first time on ponderosa pine (Pinus ponderosa) and eastern white pine (Pinus strobus) in British Columbia. This method has the potential to be a valuable tool for the detection of the pathogen in exported/imported wood products, as well as for the further identification and assessment of the distribution of North American Heterobasidion species.
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Cho SR, Koo HN, Shin S, Kim HK, Park JH, Yoon YS, Kim GH. Gamma-Ray Irradiation Control of Whiteflies Bemisia tabaci (Hemiptera: Aleyrodidae) and Trialeurodes vaporariorum in the Exportation of Fresh Strawberries. J Econ Entomol 2019; 112:1611-1617. [PMID: 31329900 DOI: 10.1093/jee/toz083] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Indexed: 06/10/2023]
Abstract
Whitefly pests, including the sweetpotato whitefly, Bemisia tabaci (Gennadius), and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood), are economically important in agriculture. With the annual growth of the domestic fresh fruit export market, various quarantine treatment methods are being used to export strawberries of better quality. The objective of the present study was to evaluate the effects of gamma rays on the development and reproductive sterility of B. tabaci and T. vaporariorum. In both species, the eggs were completely inhibited from hatching at 50 Gy, and the emergence of third-instar nymphs was completely suppressed at 150 Gy. Some adult B. tabaci and T. vaporariorum spawning occurred at 100 and 70 Gy, respectively; however, at these irradiation levels, F1 hatchability was completely inhibited. Dosimetry results showed that the penetrating power of gamma ray in the strawberry-filled box was the lowest at the mid-box position. Therefore, B. tabaci and T. vaporariorum were placed in the middle of the strawberry-filled box and irradiated. A gamma-ray irradiation of 100 Gy suppressed the development and reproduction of eggs and adults in both B. tabaci and T. vaporariorum. Our data suggest that at least 100 Gy should be used for the control of these two species of whitefly for strawberry export.
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Affiliation(s)
- Sun-Ran Cho
- Department of Plant Medicine, College of Agriculture, Life and Environment Science, Chungbuk National University, Cheongju, Republic of Korea
| | - Hyun-Na Koo
- Department of Plant Medicine, College of Agriculture, Life and Environment Science, Chungbuk National University, Cheongju, Republic of Korea
| | - Soeun Shin
- Department of Plant Medicine, College of Agriculture, Life and Environment Science, Chungbuk National University, Cheongju, Republic of Korea
| | - Hyun Kyung Kim
- Department of Plant Medicine, College of Agriculture, Life and Environment Science, Chungbuk National University, Cheongju, Republic of Korea
| | - Jong-Heum Park
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Republic of Korea
| | - Yeong Seok Yoon
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Republic of Korea
| | - Gil-Hah Kim
- Department of Plant Medicine, College of Agriculture, Life and Environment Science, Chungbuk National University, Cheongju, Republic of Korea
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Ware AB, Du Toit CLN. False Codling Moth, Thaumatotibia leucotreta (Lepidoptera: Tortricidae), Cold Disinfestation Treatment Using Grapes as the Test Medium. J Econ Entomol 2016; 109:2238-2242. [PMID: 27567224 DOI: 10.1093/jee/tow182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 07/28/2016] [Indexed: 06/06/2023]
Abstract
Some countries consider false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), a phytosanitary pest and may require the application of a mitigation treatment before accepting T. leucotreta-susceptible produce. This research reports on cold treatments that provide the phytosanitary security that this pest would not be accidentally imported alive. More than 35,000 individuals were treated for 20 d at 0.8 °C and >30,000 individuals subjected to - 0.6 °C for 18 d, with no survivors. The adoption of these treatments in international fruit trade protocols is recommended.
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Affiliation(s)
- A B Ware
- Department of Agriculture, University of Mpumalanga, Private Bag X 11283, Mbombela 1200, South Africa Agri-biotech Research Consultancies, P.O. Box 7512, Mbombela 1206, South Africa Corresponding author, e-mail:
| | - C L N Du Toit
- Agri-biotech Research Consultancies, P.O. Box 7512, Mbombela 1206, South Africa
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Abstract
PURPOSE Different doses of X-ray radiation were tested to assess the developmental inhibition effects on different stages of Drosophila suzukii, spotted wing drosophila (SWD). Efficacy of a potential quarantine treatment dose was evaluated for its practicality by a small scale-up validation test at a commercial facility. MATERIALS AND METHODS X-ray treatments at different doses of 50, 100, 200, and 300 Gy were carried out with eggs, larvae, pupae and adults of SWD. The trial at the commercial facility was performed with pupae at 150 Gy. RESULTS X-ray radiation inhibited development of all stages of SWD, and the estimated dose to cause 99% mortality or to prevent emergence (ED99) are reported here. Irradiation to eggs inhibited hatching, pupariation and adult emergence at 1962, 649 and 31 Gy, respectively. The inhibition of irradiated larvae to adult emergence was 66 Gy. Irradiation to pupae could not inhibit adult emergence completely even at 300 Gy. However, irradiation at 100 Gy and above induced complete adult sterility. Irradiation to pupae inhibited hatching of F1 eggs at 73 Gy, while for adults, total inhibition of F1 egg hatching was observed at 822 Gy. In the trial at the commercial facility, radiation at 150 Gy to pupae induced complete adult sterility in all combinations of cross-mating between treated or untreated males and females. CONCLUSION This study suggests that X-ray radiation can be recommended as an alternative to methyl bromide as phytosanitary treatment for quarantine purpose.
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Affiliation(s)
- Junheon Kim
- a Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828 , Republic of Korea
| | - Jeongmin Kim
- b Southern Forest Resources Research Center, National Institute of Forest Science , Jinju 52817 , Republic of Korea
| | - Chung Gyoo Park
- a Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828 , Republic of Korea.,c Institute of Life Science (BK21+ Program), Gyeongsang National University , Jinju 52828 , Republic of Korea
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Moore SD, Kirkman W, Hattingh V. Verification of Inspection Standards and Efficacy of a Systems Approach for Thaumatotibia leucotreta (Lepidoptera: Tortricidae) for Export Citrus From South Africa. J Econ Entomol 2016; 109:1564-1570. [PMID: 27341887 DOI: 10.1093/jee/tow139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/27/2016] [Indexed: 06/06/2023]
Abstract
A systems approach has been developed for mitigation of risk associated with Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), in citrus fruit exported from South Africa, as an alternative to a stand-alone cold treatment. This study was undertaken to assess compliance with inspection standards applicable to various steps within the systems approach and to determine its overall efficacy. Larval infestation of fruit was monitored weekly in fruit from 33 orchards, until the time of harvest, postpicking, and postpacking into export cartons. Significant positive regressions were recorded between infestation of fruit during the full monitoring period in the orchard and the last 4 wk before harvest, between the last 4 wk before harvest and on delivery to the packinghouse, and on delivery to the packinghouse and in the packed carton. There was an improvement in the level of compliance with each of these successive steps in the system, thus verifying that the grading and inspection thresholds were appropriately sensitive and confirmed the effectiveness of the system. The overall risk mitigation efficacy of the systems approach was calculated. The calculation included several known compounding under estimations of efficacy. Nonetheless, the proportion of fruit that could be infested with T. leucotreta after application of the systems approach was between P ≤ 5.328 × 10(-6) and P ≤ 8.380 × 10(-7), 6-38 times less than the proportion associated with the probit 9 (P ≤ 3.2 × 10(-5)) standard for a stand-alone cold treatment, being three survivors in 100,000 at the 95% confidence level.
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Affiliation(s)
- S D Moore
- Citrus Research International, PO Box 20285, Humewood 6013, Port Elizabeth, South Africa (; ) Department of Zoology and Entomology, Rhodes University, PO Box 94, Grahamstown 6140, South Africa
| | - W Kirkman
- Citrus Research International, PO Box 20285, Humewood 6013, Port Elizabeth, South Africa (; )
| | - V Hattingh
- Citrus Research International, Department of Horticultural Sciences, Stellenbosch University, Victoria Street, Stellenbosch 7602, South Africa
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Golding JB, Blades BL, Satyan S, Spohr LJ, Harris A, Jessup AJ, Archer JR, Davies JB, Banos C. Low Dose Gamma Irradiation Does Not Affect the Quality or Total Ascorbic Acid Concentration of "Sweetheart" Passionfruit ( Passiflora edulis). Foods 2015; 4:376-90. [PMID: 28231212 DOI: 10.3390/foods4030376] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 08/17/2015] [Accepted: 08/21/2015] [Indexed: 11/16/2022] Open
Abstract
Passionfruit (Passiflora edulis, Sims, cultivar "Sweetheart") were subject to gamma irradiation at levels suitable for phytosanitary purposes (0, 150, 400 and 1000 Gy) then stored at 8 °C and assessed for fruit quality and total ascorbic acid concentration after one and fourteen days. Irradiation at any dose (≤1000 Gy) did not affect passionfruit quality (overall fruit quality, colour, firmness, fruit shrivel, stem condition, weight loss, total soluble solids level (TSS), titratable acidity (TA) level, TSS/TA ratio, juice pH and rot development), nor the total ascorbic acid concentration. The length of time in storage affected some fruit quality parameters and total ascorbic acid concentration, with longer storage periods resulting in lower quality fruit and lower total ascorbic acid concentration, irrespective of irradiation. There was no interaction between irradiation treatment and storage time, indicating that irradiation did not influence the effect of storage on passionfruit quality. The results showed that the application of 150, 400 and 1000 Gy gamma irradiation to "Sweetheart" purple passionfruit did not produce any deleterious effects on fruit quality or total ascorbic acid concentration during cold storage, thus supporting the use of low dose irradiation as a phytosanitary treatment against quarantine pests in purple passionfruit.
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Kim J, Chung SO, Jang M, Jang SA, Park CG. Developmental inhibition and DNA damage of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) by gamma radiation. Int J Radiat Biol 2015; 91:827-32. [PMID: 26136083 DOI: 10.3109/09553002.2015.1068464] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Gamma radiation on Helicoverpa armigera Hübner was performed to assess developmental inhibition and to identify a potential quarantine treatment dose of the radiation. MATERIALS AND METHODS Gamma radiation ((60)Co) treatment at different doses of 50, 100, 200, 300, and 400 Gy was carried out with egg, larvae, pupae and adults of H. armigera. RESULTS Gamma radiation induced developmental inhibition of all stages of H. armigera. The effective dose values required for inhibition 99% (ED(99)) of hatching, pupation and adult emergence from the irradiated eggs were 550.7, 324.9 and 136.4 Gy, respectively. ED(99) values for inhibition of the larvae to adult emergence was 200.0 Gy. Irradiation on pupae could not completely inhibit adult emergence even at 400 Gy. ED(99) value for inhibition of F(1) egg hatchability from the irradiated adults was estimated to be 229.5 Gy. CONCLUSIONS This study suggests that gamma radiation is a possible alternative to phytosanitary treatments. Irradiation treatment with minimum dose of 200 Gy can be suggested as optimum dose for larval treatment in quarantine.
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Affiliation(s)
- Junheon Kim
- a Institute of Agriculture and Life Science (BK21+program), Gyeongsang National University , Jinju, Gyeongnam , Republic of Korea
| | - Soon-Oh Chung
- b Division of Applied Life Science (BK21+program), Gyeongsang National University , Jinju, Gyeongnam , Republic of Korea
| | - Miyeon Jang
- b Division of Applied Life Science (BK21+program), Gyeongsang National University , Jinju, Gyeongnam , Republic of Korea
| | - Sin Ae Jang
- c Institute of Life Science, Gyeongsang National University , Jinju, Gyeongnam , Republic of Korea
| | - Chung Gyoo Park
- a Institute of Agriculture and Life Science (BK21+program), Gyeongsang National University , Jinju, Gyeongnam , Republic of Korea.,b Division of Applied Life Science (BK21+program), Gyeongsang National University , Jinju, Gyeongnam , Republic of Korea
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Ngamchuachit P, Barrett DM, Mitcham EJ. Effects of 1-methylcyclopropene and hot water quarantine treatment on quality of "Keitt" mangos. J Food Sci 2014; 79:C505-9. [PMID: 24592887 DOI: 10.1111/1750-3841.12380] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/27/2013] [Indexed: 12/01/2022]
Abstract
The optimal 1-methylcyclopropene (1-MCP) treatment to slow ripening of whole "Keitt" mangos, either alone or in combination with hot water treatment (HWT) (prior to or post 1-MCP) was identified. USDA-APHIS mandates that HWT can be used for control of fruit flies, but this may affect fruit response to 1-MCP. Mangos were evaluated by repeated measurement of nondestructive firmness, peel color, and ethylene production on the same mango fruits during 2 wk of ripening at 20 °C after treatment. The magnitude of ethylene production increased as a result of both 1-MCP and HWT. With softer mangos (65 N), treatment with 1-MCP alone delayed fruit softening and extended the number of days to full-ripeness (25 N) from 5 d in untreated fruit to 11 d. For these riper fruit, application of 1-MCP prior to HWT extended the days to full-ripeness to 9 d compared with 7 d when 1-MCP was applied after HWT. With firmer mangos (80 N), 1-MCP treatments alone prolonged the days to full-ripeness to 13 d as compared to 11 d for the untreated fruit. There was no significant concentration effect on firmness retention among 1-MCP treatments (0.5, 1.0, or 10.0 μL/L). HWT resulted in a faster rate of fruit softening, taking only 7 d to reach full-ripeness. Combining 1-MCP with HWT reduced the rate of softening compared to HWT alone, resulting in 9 to 11 d to full-ripeness. Application of 1-MCP before HWT showed a greater ability to reduce the rate of fruit softening compared with 1-MCP treatment after HWT.
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Affiliation(s)
- Panita Ngamchuachit
- Dept. of Food Technology, Chulalongkorn Univ., Bangkok, Thailand; Dept. of Food Science and Technology, Univ. of California, Davis, CA, U.S.A
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