2002 Volume 71 Issue 6 Pages 796-804
Three tenths percent NaCl added to the 1/5 strength Enshi standard solution to which cabbage plug seedlings were subirrigated once (1 minute) a day for 5 days of the end of nursery term (NaCl treatment). As a result, the seedlings underwent a moderate water stress without drying the rootballs. The effect of NaCl treatment on quality of seedlings and its practical uses are as follows : (1) Shoot water potential of seedlings was lowered without limiting irrigation by NaCl treatment due to reducing the water potential of the rootball. (2) Shoot length and leaf area were restricted without decreasing shoot dry weight and increased the dry matter ratio of seedlings. Their leaf area equaled that of control seedlings a week after transplanting. The NaCl treatment did not decrease cabbage yield. (3) The Na content of seedlings increased but it decreased after transplanting, whereas the K, Ca and Mg contents decreased but recovered a week after transplanting. (4) The amount of epicuticular wax increased by about 20% which improved the ability of seedlings to maintain their moisture content by suppressing the loss of moisture after transplanting. (5) Two days after the start of the NaCl treatment, stomatal conductance and transpiration rate decreased and water use efficiency increased. These results show that the NaCl treatment of cabbage plug seedlings suppressed succulent growth without drying the rootball. We conclude that the NaCl treatment promotes the establishment of seedlings after transplanting by improving their drought resistance and ensuring early growth.