关键词: 番茄, 砧木, 嫁接, 低温胁迫, 耐冷性

Abstract:

In order to investigate the effect of tomato rootstock，scion and their potential interaction on chilling tolerance，we grafted chilling-sensitive tomato cultivar‘060911’（S）and chilling-resistant tomato cultivar‘060112’（R）. We then selectively removed rootstock or scion from the grafted seedlings RS/RS，and incubated the newly formed 9 kinds of seedlings，i.e.，RS/RS，RS/R，RS/S，R/RS，S/RS，S/R，R/S，R/R，S/S in the growth chamber with light intensity of 22 klx and photoperiod 12 h/12 h. The seedlings were treated with low temperature at 10 ℃/3 ℃ for 9 days and recovered at 25 ℃/15 ℃ for 3 days. Chilling injury index，root activity，electrolyte leakage and osmotic adjustment substances were measured after the chilling treatment and after the recovery. Grafted seedlings behaved similarly in root activity，electrolyte leakage of root and leaf，soluble sugar and proline content before the chilling treatment，but showed significant difference after the chilling treatment and after the recovery. Among these 9 kinds of grafted seedlings，S/S seedlings displayed the highest while R/R seedlings displayed the lowest chilling injury index. Meanwhile，R/R seedlings showed the lowest electrolyte leakage，and the highest content of soluble sugar and proline. Meanwhile，R/R seedlings showed the lowest electrolyte leakage，and the highest content of soluble sugar and proline. While R/RS，RS/R，RS/S，S/RS seedlings were intermediate between R/R and S/S regarding the chilling injury index，electrolyte leakage，soluble sugar and proline content. Results indicated that both rootstock and scion are important for chilling tolerance. We further found that rootstock conferred higher chilling resistance than scion，due to the fact that the chilling tolerance of RS/RS was higher than that of S/RS，but lower than R/RS. Moreover，the chilling tolerance of RS-R was significantly higher than that of RS-S，and the P value of interaction was less than 0.01. The results showed that rootstock and scion had significant interaction effect on the chilling tolerance of grafted seedlings.

Key words: tomato, rootstock, grafting, low temperature stress, cold resistance