Impact of ethylene and 1-MCP on sprouting and sugar accumulation in stored potatoes

• Ethylene applied post-dormancy break inhibited sprout growth in cv. Russet Burbank.
• Ethylene applied post-dormancy break had little/no effect on sugar accumulation.
• Differential effects of ethylene/1-MCP on sprouting and sugar accumulation.
• Hence ethylene may influence dormancy/sugars though differential ethylene receptors.

Long term storage of potato tubers allows year round availability of the crop but is limited by sprouting. Continuous exposure to ethylene during storage prolongs storage life of potatoes by suppressing sprouting, yet there is a lack of information on whether continuous ethylene treatment is required throughout storage. Potato cvs. Saturna and Russet Burbank were stored at 6 °C under four ethylene treatments (viz. continuous ethylene (10 μL L−1), continuous air, transfer from air to ethylene after first indication of sprouting and vice versa) for thirty weeks in 2008–2009 (Year 1). In Year 2 (2009–2010), tubers were stored under the same treatments and duration as in Year 1, with the addition of 1-MCP (1 μL L−1) applied for 24 h at harvest or at first indication of peeping. Samples were taken after harvest and at specific intervals during storage. Respiration rate measured at each sampling point. Fructose, glucose and sucrose were determined in potato flesh of all cultivars as ethylene has been reported to have some negative effects on non-structural carbohydrate metabolism. Sprouting was also measured at the end of the experiment. Ethylene applied after first indication of sprouting was as effective at suppressing sprouting for cv. Russet Burbank as when applied continuously; the implications of which are that the cost of ethylene application in store rooms could be reduced by manipulating timing of continuous application. In addition, application of ethylene after the first indication of sprouting had little to no effect on tuber sugar accumulation compared with continuous ethylene application from harvest.