Abstract
Bean thrips (BT), Caliothrips fasciatus (Pergande), is a pest of concern to certain countries that import fresh citrus fruit from California, USA. A series of laboratory-scale exploratory fumigations with phosphine at 4.9 ± 0.3 °C (mean ± 2 SD; x¯±2s) were conducted to evaluate the postharvest control of adult BT. Models of the duration–mortality response predicted ca. 99% mortality of BT populations when headspace concentrations of phosphine, [PH3], are maintained at levels ≥0.4 g m−3 (250 ppmv (µL L−1)) and ≤1.5 g m−3 (1000 ppmv (µL L−1)) for 12 h, with the duration representing the lower bound of the 95% confidence level (CL). Confirmatory fumigations, each lasting 12 h, were then conducted using BT-infested sweet oranges, Citrus sinensis (L.), at pulp temperature (T) ≤ 5 °C to corroborate the exploratory results. Three formulations of cylinderized phosphine were used: 1.6% phosphine by volume in nitrogen, VAPORPH3OS®, and ECOFUME®, all applied at two levels, ca. 1.5 g m−3 (1000 ppmv (µL L−1)), as well as 0.5 g m−3 (300 ppmv (µL L−1)). Collectively, across the formulations, an applied dose of ca. 1.5 g m−3 (1000 ppmv (µL L−1)) resulted in 0 survivors from 38,993 (probit 8.60, 95% CL; probit 9, 72% CL) treated BT, while an applied dose of 0.5 g m−3 (300 ppmv (µL L−1)) resulted in 0 survivors from 31,204 (probit 8.56, 95% CL; probit 9, 70% CL) treated BT. Results were discussed in the context of commercial and operational features of quarantine and pre-shipment (QPS) uses of phosphine to treat fresh fruit and, specifically, the control of BT in fresh citrus exported from California, USA, to Australia.
Highlights
To satisfy the ever-increasing demand for food quality, safety, and security in domestic and international markets, horticultural producers must find the safest and most economical ways to control insect pests
Results were discussed in the context of commercial and operational features of quarantine and pre-shipment (QPS) uses of phosphine to treat fresh fruit and, the control of Bean thrips (BT) in fresh citrus exported from California, USA, to Australia
These results indicate that the narcosis threshold for adult BT at air temperature 4.9 ± 0.3 °C ( x 2 s ) spans [PH3] ≥ 0.4 xare 2 s [PH
Summary
To satisfy the ever-increasing demand for food quality, safety, and security in domestic and international markets, horticultural producers must find the safest and most economical ways to control insect pests. While efforts continue across the gamut of postharvest strategies (e.g., cold-treatments, heat-treatments, irradiation, controlled-atmosphere, fogging, etc.), fumigation remains an invaluable option for insect pest control [1]. Methyl bromide, has dominated the postharvest treatment of horticultural crops over the last four decades, being the primary option for quarantine and pre-shipment (QPS) disinfestations, where pest-free security must be “guaranteed”. This use has resulted in a global horticultural industry, producers, and port facilities alike, with logistics and infrastructure largely geared to conduct QPS methyl bromide fumigations. Many dynamics surround the continued use of postharvest methyl bromide for QPS treatments [2]. Any alternative fumigants must have a labeled use, and cor-
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.