บทคัดย่องานวิจัย

Post-harvest 1-MCP treatment affects shelf life depending upon storage temperature in nectarines: relationship with polyamine titres.

Ziosi V., Bregoli A.M., Rasori A., Biondi S., Costa G., Torrigiani P.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.57

2004

บทคัดย่อ

Post-harvest 1-MJCP treatment affects shelf life depending upon storage temperature in nectarines: relationship with polyamine titres.  1-methylcyclopropene (1-MCP) inhibits ethylene action and fruit quality achievement by binding to ethylene receptors.Developmental stage, timing and concentration and storage temperature may modulate MCP effects.In preclimacteric nectarines a single MCP treatment induced a decrease in ethylene production and biosynthesis, while repeated treatments retarded the induction of ethylene emission and ACS1 and ACO1 transcript accumulation (Mathooko et al. 2001 PBT 21:265-281)).Plants may overcome MCP action through synthesis of new receptors (Rasori et al.2002 JEB 53: 2333-2339).Ethylene and the growth regulators polyamines (Pas) share the precursor S-adenosylmthionine.An inverse relationship has been suggested in several physiological processes.At ripening in peach, as well as in other climacteric fruit, PA levels are at their minimum.Exogenous PA treatment in pre-harvest inhibited ethylene production and fruit softening in peaches and nectarines with effects o­n ACS and ACO transcript levels (Bregoli et al. 2002 Physiol Plant 114: 472-481, Torrigiani et al.2004 PBT, in press).A role for Pas in post-harvest is also emerging probably correlated with their antisenescence and antistress properties.

To clarify the role of ethylene and its relationship with Pas, MCP effects o­n post-harvest have been studied at 25 and 4 °C in Stark Red Gold nectarines.At 25 °C, MCP strongly inhibited ethylene production, and ACS and ACO expression, and caused an increase in PA levels.At 4 °C ethylene production was not altered, although ACS and ACO mRNAs were affected, while PA concentration was further enhanced.A transient PA increase in associated with MCP treatment at both temperatures, independent of ethylene production, suggesting a correlation with MCP- and/or cold stress.MCP is more active at 25 °C, but effect o­n quality are also observed at 4 °C.Pas could help in maintaining fruit quality.