Abstract
The application of ethylene to germinating seeds in the practical production of mungbean sprout has been used to get thicker, shorter and harder hypocotyls. In our experiment, a similar response was induced by 2-chloroethyl phosphonic acid treatment (2-CPA). Neutral sugar concentration of the pectin fraction was higher in 2-CPA-treated hypocotyls than in non-treated ones throughout the experiment, while uronic acid concentration in the 2-CPA-treated ones was slightly higher than that in the non-treated on days 3 and 5. In water-soluble pectin, a lower concentration of galactose and a higher concentration of arabinose and rhamnose (and/or xylose) in 2-CPA-treated hypocotyls as compared to the non-treated ones were observed on days 1 and 3. From these results, we hypothesized that the changes in neutral sugar concentration and composition of water-soluble pectin fraction by 2-CPA-treated might contribute to physical and/or morphological change in these hypocotyls.
