Pyruvic Acid and Sugar Contents according to Bulb Growth Stage in Onion
2009
Lee, E.J., Kyungpook National University, Daegu, Republic of Korea | Suh, J.K., Kyungpook National University, Daegu, Republic of Korea
This study was designed to investigate the pungency response according to the bulb growth stage in onion (Allium cepa). The number of leaves, plant height and bulb scales were significantly increased as the plants grew rapidly after winter. As the bulbs began to enlarge, plant height and the number of leaves were decreased but the weight and diameter of bulbs were significantly increased. The bulbing index (bulb diameter/neck diameter) showed a sharp increase, while the bulb shape index (bulb height/bulb diameter) was reduced. Dry matter rate and crop growth rate (CGR) were increased as bulb enlarged, but remarkably decreased as the bulb enlarged in the harvest time. The pyruvic acid and sugar content in onion bulb were gradually increased as the duration of growth became longer. However, the pyruvic acid content per unit weight of the bulb was temporarily decreased as plant height increased, but increased rapidly again as bulb progressively enlarged. Afterwards it was gradually decreased as bulb got bigger on the account of dilution of chemical constituents in harvest time. The pyruvic acid content per unit weight of the leaf was higher than that of the bulb in the beginning of growth, but it showed a sharp decrease as the bulb enlarged. Sugar content per unit weight of bulb and leaf were increased continuously owing to a translocation of photosynthate, but afterwards it was gradually decreased as bulb got bigger. Also, the content of sugar in a unit size of bulb was higher than that of leaf.
显示更多 [+] 显示较少 [-]