Carbon dioxide, oxygen and ethylene effects on potato tuber dormancy release and sprout growth

Abstract

The possible roles of oxygen and carbon dioxide treatments in the presence or absence of ethylene on tuber dormancy release in potato (Solanum tuberosum L.) were examined. Using two gas compositions (I: 60 % CO2-20 % O2-20 % N2 and II: 20% CO2-40% O2-40% N2), the phase of tuber dormancy and previous storage temperature were demonstrated to be important parameters for dormancy release by these gas mixtures. Gas I caused decreased abscisic acid (ABA) levels within 24 h regardless of previous storage temperature, although this effect was reversible. Exogenous C2H4, an effective dormancy release agent, also caused decreased ABA levels within 24 h. It also enhanced dormancy release and further promoted ABA losses by gas I. Gas II treatment led to slight reductions in ABA levels that were further decreased by C2H4. Sprout length was modelled successfully by multiple regression analysis in terms of glucose and ABA levels within the apical eye tissues of Russet Burbank tubers immediately after, and regardless of, previous gas treatments or storage temperatures.