Effects of preharvest application of aminoethoxyvinylglycine (AVG) on harvest maturity and storage life of ‘Unique’ feijoa

Abstract

ABSTRACTIn a previous study, feijoa harvested earlier than ‘touch-picked’ maturity appeared visually acceptable after 6 weeks of storage but had low soluble solids content (SSC) and high titratable acidity (TA). Given that feijoa display climacteric-like behaviour, manipulation of ethylene physiology prior to harvest may have the potential to alter this outcome. Subsequently, the aim of this work was to investigate the impact of preharvest aminoethoxyvinylglycine (AVG) application on feijoa quality at harvest and during subsequent storage. The experiment comprised of three preharvest AVG treatments and two harvest occasions. AVG treatment dramatically reduced preharvest fruit drop. AVG treatment at 4 weeks before current commercial harvest timing was effective in delaying maturity. AVG treatment suppressed ethylene production rates during storage. However, AVG treatment did not alter quality (firmness, SSC, TA and flesh colour) after storage. This result adds to the evidence that postharvest ripening in feijoa may be regulated independent of ethylene despite the typical climacteric increase in ethylene observed. The results also confirmed that fruit harvested early were storable for 6 weeks without exhibiting internal browning, but having a high TA and low SSC that may affect their taste acceptability.