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Abstract : |
The objective of this study was to understand the effect of environmental changes during growth and after harvest on the quality of lettuce. In both cultivars and portions, acid invertase activities (soluble and cell wall-bound fractions) increased throughout the harvest month, except in April in the leaf portion. SS and SPS activities declined with few fluctuations in any portions of both cultivars. The activities of three sucrose metabolizing enzymes were higher in the midrib than in the leaf portions. Sucrose concentration increased from December to a maximum in January and again decreased up to April. On the other hand, glucose and fructose concentrations declined up to March and increased in April. There was a highly significant negative correlation between the activity of acid invertase in cell wall-bound fraction and sucrose content. A higher concentration of reducing sugars was found in `Bittsu` than `Shisuko`. Fructose was higher than glucose and sucrose contents in the both portions of two cultivars., |
