CHANGES IN LIPIDS AND ELECTROLYTE LEAKAGE DURING NON-NETTED MUSKMELONRIPENING

Respiration, C2H4 production, lipid composition, and electrolyte leaka ge were monitored during ripening of two nonnetted muskmelon (Cucumis melo L.) varieties differing in their storage life: 'Clipper' (a long- storage-life variety) and 'Jerac', which was used as a control, Respir ation rates were comparable in both varieties, Although 'Jerac' exhibi ted normal climacteric C2H4 production, 'Clipper' continued to produce significant amounts of C2H4 until senescence. Electrolyte leakage inc reased with ripening and was always higher in 'Jerac', The loss of mem brane integrity seems to be related to changes in the lipid compositio n due to a breakdown of phospholipids, an increase of sterol synthesis , and an increase in fatty acid saturation, On the contrary, in 'Clipp er', the absence of a major change in sterol and phospholipids content and the high level of fatty acid unsaturation suggest that membrane p ermeability is not greatly affected during ripening, This is consisten t with the low loss of solutes measured and may delay senescence in 'C lipper' fruit.