1. Inhibition of ethylene action in cherimoya fruit is effective in blocking autocatalytic ethylene production and prolonging postharvest life
Julio Retamalesa, Bruno G. Defilippia,b, Daniel Manríquezc and Reinaldo Campos-Vargasa
aInstitute for Agricultural Research, La Platina Experimental Station, Santiago, Chile;
bPomology Department, University of California-Davis
cBiotechnologie, ENSAT/INP, Toulouse, France
INTRODUCTION
Inhibition of ethylene action in fruits has been carried out within the framework of a research project (FONDECYT ) in Chile. Two trials in consecutive years (2000 and 2001) were conducted on Concha Lisa cherimoya (Annona cherimola Mill.) fruit by applying 1-methylcyclopropene (1-MCP), an ethylene action inhibitor. Fruit were applied right after harvest with 1-MCP at different concentrations (0, 600, and 1200 ppb in the first year; 0, 75, 150, 300, and 600 ppb in the second year). Fruit was stored at 10ºC followed by shelf life periods at 20ºC, evaluating fruit firmness, soluble solids, titratable acidity, peel color, ethylene production and respiration together with development of physiological disorders and weight loss. Inhibition of ethylene action by 1-MCP resulted in marked effects according with the applied dosage, with fruit showing reduced autocatalytic ethylene production (Fig. 1), respiration (Fig. 1) and softening (Fig. 2), both during cold storage and in shelf life. High incidence of decay and senescence limited postharvest life in cherimoya and could be effectively controlled by 1-MCP (Figs. 3 and 4). Thus, fruit treated with 1-MCP could be stored for 21 and 28 days in 2000 and 2001, respectively, allowing subsequent shelf life and ripening, while fruit from control treatment was already in advanced ripeness at 21 and 14 days and could not withstand any further shelf life after such periods.
RESULTS
Figure 1. Respiration and ethylene production in cherimoya non-treated and treated with 1-MCP during shelf life. Season 2000 (* means differences at P0.05)
Figure 3. External and internal appearance of cherimoya non-treated and treated with 1-MCP during shelf life after (a) 14 or (b) 28 days at 10ºC. Season 2001 b a
CONCLUDING REMARKS
1-MCP showed potential to inhibit ripening and senescence in highly perishable cherimoya fruit.
Further work is required to adjust 1-MCP application to expected postharvest life according to prospective markets.
ACKNOWLEDGMENTS
To FONDECYT (Chilean Scientific and Technological Research Fund) for supporting this research through Project
To AgroFresh (Philadelphia, PA) for providing SmartFresh (a.i. 1-MCP).