水耕法による外生アスコルビン酸ナトリウムのサラダナへの導入

Abstract

The effects of administering 1000 and 2000 ppm sodium ascorbate (NaAs) to roots of lettuce (butter head type) just prior to harvest for 24 hr on the foliar L-ascorbic acid (AsA) content were studied. The results were as follows.1. The water absorption ability of the roots was lowered by increasing NaAs concentration such that plants exposed to 2000 ppm withered.2. When roots were exposed to 1000 and 2000 ppm NaAs, the AsA contents of the leaves increased 3.5 and 4.7 times over those of the control plants. The AsA content in the lettuce leaves kept at 5°C for 3 days after treatment did not decrease significantly and the appearance of leaves from the treated plants was similar to that of the control.3. The K, Ca and Mg contents of leaves from the treated plants were similar to those of the control, which suggests that the mineral content in the leaves was unaffected by the treatment.Although the production of lettuce (butter head type) with abundant L-ascorbic acid content was shown to be possible, there are still some problems to be solved before this method can be put into practical use.