You are looking at 11 - 12 of 12 items for
- Author or Editor: Irving L. Eaks x
Relationships among fruit age, epicuticular wax, weight loss, internal atmosphere composition, and respiration were investigated in mature ‘Washington’ navel orange fruit [Citrus sinensis (L.) Osbeck]. Fruit epicuticular wax, internal CO2, and internal C2H4 increased, whereas as the season advanced, weight loss during storage and respiration decreased. Concomitantly, fruit conductance to CO2 was reduced. GA3 (10 ppm) application prior to fruit color break reduced the increase in epicuticular wax and thereby delayed the decrease of CO2 conductance, resulting in less of an increase in internal CO2. GA3-treated fruit were not consistently different for other parameters evaluated. Chemical name used: lα,2β,4aα,4bβ,10β)-2,4a,7-trihydroxy-l-methyl-8-methylenegibb-3-ene-l,10-dicarboxylic acid l,4a-lactone (gibberellic acid).
An investigation was performed with the goal of identifying, at the biochemical level, organelles that undergo postharvest change during ripening in avocado fruits (Persea americana Mill. cv. Hass). Membrane vesicles from mesocarp tissue at defined stages of ripening were fractionated by linear density gradient centrifugation and then assayed for characteristic marker activities. These measurements indicated that the Golgi and plasma membranes increased in buoyant density from 1.11 g·cm−3 to 1.14 g·cm−3 and from 1.15 g·cm−3 to 1.17 g·cm−3, respectively, during ripening. The endoplasmic reticulum exhibited a smaller increase in density, while thylakoids and mitochondrial membranes showed no shifts in density during ripening. These membrane changes were apparent at the peak (predicted from measurements of C2H4 production) of the respiratory curve that characterizes climacteric fruit ripening and were sustained for at least 6 days past the respiratory peak. Colorimetric lipid analyses of plasma membrane-enriched fractions indicated that the buoyant density increase during ripening was due, in part, to a decrease in the glycolipid : protein ratio. Electrophoretic analyses of fractions containing peak total activities of Golgi, thylakoids, or plasma membrane revealed several changes in the polypeptide banding patterns during ripening.