The effects of postharvest carbon dioxide and a cold storage treatment on Tuta absoluta mortality and tomato fruit quality

Tuta absoluta is an invasive pest species that affects tomatoes and other solanaceous crops and is found in Europe and other Mediterranean areas. Hitherto, fumigation with methyl bromide is the only measure used to control this pest during the postharvest period. Because of methyl bromide phytotoxicity and health, safety and environmental concerns, alternatives to this product need to be investigated. Therefore, the objective of this study was to determine the ability of T. absoluta to complete its preimaginal development on tomato fruit during the postharvest period and to evaluate the effectiveness of different supra atmospheric carbon dioxide (CO2) levels and cold storage treatments on T. absoluta control. T. absoluta was unable to complete its development from egg to adult on fruit of three tomato varieties. In contrast, T. absoluta completed its preimaginal development when more mature larvae were provided with the tomato fruit. The exposure of T. absoluta to a modified atmosphere of 95% CO2 at 25 °C for 48 h was effective for the control of all life stages, but negatively affect fruit quality. An increment in the exposure time to 72 h was necessary in order to obtain the same level of control at 40% CO2. A cold storage treatment at 1 °C for a total of 10 days was also effective for the control of the T. absoluta eggs. These two treatments did not negatively affect the quality of the fruit. Therefore, these appear to be effective alternatives to postharvest methyl bromide fumigation and future studies need to be planned to validate the commercial feasibility of these findings.This work was partially funded by the Spanish ‘Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA; project CC09-048-C4-1) and the European Union (FEDER Program). We thank Carburos Metálicos-Air Products Group (Spain) for providing the gases. This manuscript is dedicated to the memory of Dr. Miguel Ángel del Río who provided unconditional friendship, guidance and support. We are grateful to the two anonymous reviewers for their comments and suggestions