Ripe mangoes`Tommy Atkins' were exposed to UV-C irradiation for 10 and 20 min, prior to storage for 14 days at 5 or 20°C and a shelf-life period of 7 days at 20°C. UV-C-treated fruit maintained better visual appearance than unirradiated controls. UV-C irradiation for 10 min was the most eective regime in suppressing decay symptoms and maintaining ®rmness during storage at 5 or 20°C. Such fruit (treated with UV-C for 10 min) showed greater levels of putrescine and spermidine after cold storage than controls and those treated with UV-C for 20 min. Higher levels of sugars and lower levels of organic acids were observed in mangoes treated with UV-C for 20 min. However, the most eective UV-C treatment (10 min) for reducing decay maintained sugar and organic acid levels similar to the controls. No UV-damage was observed on treated fruits after storage. These results indicate that UV-C irradiation could be used as an eective and rapid method to preserve the postharvest life of ripe mangoes without adversely aecting certain quality attributes.

ABSTRACT

An isolate of camptothecin alkaloids was applied to the eyes or sprouts on potatoes (Solanum tuberosum L.) as lanolin suspensions at concentrations of 1.5, 3, 9, and 15 mM, or to the whole tubers as aqueous sprays or dips at various concentrations. Potato sprouting at 15°C was completely inhibited for 4 weeks by all the lanoline suspensions. Inhibition was greater than 95% when a solution of the alkaloids at 5 × 10−1 mM was applied to the tubers as a 3-spray or 3-dip treatment. The camptothecin treatments that inhibited sprouting also reduced weight loss of potato tubers; and even after 4 months at 15°, no symptoms of internal sprouting or other deleterious effects were evident. Electron micrographs of sprouts suggest that camptothecin inhibited sprouting by inducing structural changes in vascular tissues and interfering with cell division in the meristematic portions of the sprouts.