Cold stress response and the small Heat Shock Proteins in tomato fruit

M. ESCOBAR; M. D. RÉ; M.L. SOSSI; S.B. BOGGIO; BOGGIO, SB; VALLE EM

Mar del Plata

Congreso; SAIB 2015; 2015

Ripening is the late developmental phase of tomato (Solanum lycopersicum L) fruit that starts when the green fruit reaches the final size and is completed when the fruit is red. This process also occurs in mature green fruits that have been harvested. Shelf life, one of the most important agronomic traits for tomato, is lengthened by storing fruit at low temperature. Susceptible fruits suffer physiological disorders known as chilling injury. It has been reported that small heat shock proteins (sHSP) accumulated under cold stress. The overall objective of this study was to evaluate the role of sHSP under chilling conditions in fruits from two tomato cultivars, cv Micro-Tom (tolerant to chilling stress) and Minitomato (sensitive to cold stress). Additionally, fruit from transgenic plants with altered level of a mitochondrial sHSP in these two cultivars were analysed in their phenotype, antioxidant response, gene expression and sHSP protein levels. Transgenic and non-transformed plants were phenotypically similar under control conditions. Results showed that sHsps were induced during ripening in fruit from both cultivars. However, in Micro-Tom fruit but not in Minitomato fruit sHsps were induced in response to storage at low temperature. Silenced fruits were more susceptible to chilling injury while overexpressing fruits were more tolerant to the cold treatment. These results substantiate the hypothesis that sHsps may participate in the mechanism of genotype chilling tolerance. Overall these data indicate that sHSPs are involved in the response of tomato fruit to cold stress, which could have implications for developing tomato cultivars tolerant to environmental stress.