CELL WALL METABOLISM IN ?DIXILAND? PEACHES AFTER HARVEST AND HEAT TREATMENT

BUSTAMANTE, CLAUDIA; LAUXMANN, MARTÍN ALEXANDER; BORSANI, JULIA; LOMBARDO, VERONICA; BUDDE, CLAUDIO OLAF; MURRAY, RICARDO; ANDREO, CARLOS SANTIAGO; LARA, MARÍA VALERIA; DRINCOVICH, MARÍA FABIANA

San Miguel de Tucumán, Tucumán, Argentina

Congreso; XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009

Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB)

Refrigeration of peaches during marketing and shipping affectsfruit quality causing physiological disorders collectively namedchilling injury (CI). To alleviate CI, different strategies have beenapplied before cold storage, among them heat treatment (HT) havebeen widely used. In this work, we analyze ethylene production,fruit firmness and the expression of enzymes and proteins involvedin cell wall metabolism in peaches immediately after harvest (C),during ripening at 20ºC for 3, 5 and 7 d (C+3, C+5 and C+7), or afterexposed to 39ºC for 3 d (TT) followed by 3 d at 20ºC (TT+3). Forthe group of fruit kept at 20ºC, a typical softening behaviour wasobserved, as well as an increase in ethylene production. In contrast,during the 3 d of HT, fruit maintained their firmness, which rapidlydecreased after transfer to 20ºC. Relative expression of genesencoding proteins involved in cell wall metabolism was analyzedby qRT-PCR. Cell wall-related genes showed different expressionpatterns during ripening at 20ºC. However, TT decreased markedlythe accumulation of all of them. Once TT fruits were transferred to20ºC after HT, an increase in gene expression occurred to differentextent depending on the transcript analysed. This study will help inthe identification of the principal cell wall proteins involved inpeach softening and their putative role in some CI symptomsalleviation.