Effects of post-harvest salicylic acid treatment on fruit quality and anti-oxidant metabolism in pineapple during cold storage.

摘要

Pineapples (cv. Comte de Paris) at commercial maturity (180 fruits per treatment, 3 replicates) were immersed in 0, 1.0, 3.0 or 5.0mM salicylic acid (SA) for 15 min, then stored at 10 degrees C and 90% RH for 20 days. After 20 days in cold storage they were moved to 20 degrees C for 2 days to simulate shelf life. Physiological and biochemical responses were studied. Results showed that 3.0 or 5.0mM SA treatments decreased the internal browning (IB) index, while 5.0mM SA treatment decreased the soluble solids content, titratable acidity and soluble sugar content, but increased ascorbic acid levels at the end of shelf life. Also, during cold storage, all SA treatments decreased the rate of tissue respiration in pineapples markedly. SA at 5.0mM decreased the activities of peroxidase, polyphenol oxidase (catechol oxidase) and phenylalanine ammonia-lyase markedly, but increased the activities of superoxide dismutase and ascorbate peroxidase compared with the non-SA treated (untreated) controls. Results suggest that post-harvest treatment with 5.0mM SA delayed the occurrence of IB in pineapples, extended shelf life and maintained fruit quality during cold storage.