Relationships between Jasmonates and Chilling Injury in Mangosteens Are Affected by Spermine

Effects of low temperature and chilling injury (CI) on jasmonic acid (JA) and methyl jasmonate (MeJA) concentrations were investigated in mangosteens (Garcinia mangostana L.). JA concentrations in the skin of fruit stored at 7 °C increased signifi cantly compared with that of those stored at 13 °C, but JA decreased with the occurrence of vis- ible symptoms of CI. Neither an increase in JA nor CI was detected in pulp of fruit stored at 7 °C. JA concentrations in the skin of fruit treated with spermine (Spm) and stored at 7 °C also increased, but at a lesser extent than in untreated fruit. Thus, the response of JA to low temperatures appears to be limited to chill-susceptible parts of the fruit. The decrease of JA and the onset of CI was delayed in fruit treated with Spm kept at 7 °C compared with untreated control fruit. Exogenous application of n-propyl dihydrojasmo- nate, which is a jasmonic acid derivative, effectively decreased CI. These results suggest that low temperature-induced JA accumulation may play a protective role against CI. The application of jasmonates may increase chill-resistance in fruit. Jasmonates—jasmonic acid (JA) and methyl jasmonate (MeJA)—have a role in the inhibition of growth (Tsai et al., 1997), leaf yellowing (Tsai et al., 1996), and stomatal closure (Riov et al., 1990) of plants. The effects of jasmonates in fruit have also been examined. For instance, jasmonates infl uenced ethylene production either positively or negatively, depending on the fruit developmental stage in apples (Malus sylvestris (L.) Mill. var. domes- tica (Borkh.) Mansf. ) (Saniewski et al., 1986). The role of jasmonates may vary among fruit because changes in jasmonates differ between climacteric and nonclimacteric fruit types (Kondo et al., 2000). Jasmonates may also have a role as protective substances against stress. MeJA application reduced chilling injury (CI) in tomatoes (Lycopersicon esculentum L.) and papayas (Carica papaya L.) (Ding et al., 2001; Gonzalez-Aguilar et al., 2003). However, the effect of chilling temperature on endogenous jasmonates in fruit is not clear. Marketability of mangosteens decreases when fruit are stored below 8 °C because of CI development in the skin (Augustin and Azudin, 1986). Production of stress ethylene, which caused stresses, differs according to the particular stress (Saltveit, 1992). Although jasmonates may be involved in stress result- ing from both low temperatures and CI, the degree of response may differ. Polyamines are generally abundant in immature tissues and exogenous application of polyamines has an antisenescence effect (Kaur-Sawhney and Galston, 1991). Furthermore, polyamines have the effect of protecting membrane lipids from peroxidation (Kramer and Wang, 1989). Spermine (Spm) applications after harvest inhibited CI in squashes (Cucurbita pepo L.) (Kramer and Wang, 1989) and decreased CI in mangosteens (Kondo et al., 2003). If the reaction of JA depends not on the low tem- perature treatment but on the potential for CI, polyamine application that decreases CI at low temperatures may infl uence the response of endogenous jasmonates. In this study, the ef- fects of low temperature and CI on endogenous jasmonates were investigated in the skin and pulp of mangosteens. Furthermore, the infl u- ence of Spm on CI and on chilling-induced changes in JA were examined.