Abstract
The growth of taproot of carrot (Daucus carota L. cv. Natumaki-senkogosun) cultured under hydroponics was investigated. Plants were cultured in boxes containing half strength Enshi solution. Keeping the solution surface level about 7 cm below the base of the root, aeration was performed at 0 (non-aerated), 5 and 60 minutes in each 1-hour cycle. Though the weight of storage root was not influenced by the aeration period, the length of swelling in the root axis increased with the aeration period (Exp. 1). The taproot was grown in a shallow box with a mesh bottom suspended in a large case containing the same solution as used in Exp. 1. The nutrient solution was continuously aerated. The weight and length of the swelling of taproot not submerged in solution were larger than those of submerged taproot. A high rate of root cracking occurred in the submerged taproots (Exp. 2).
