| 【Objective】 The study was conducted to investigate the effect of root exudates on Cd absorption and
accumulation of water spinach ( Ipomoea aquatica Forsk). 【Method】 By using water-soil culture method, typical varieties of I.
aquatica Forsk with low Cd accumulation (QLQ) and high Cd accumulation (T308) were planted in water culture to collect
root exudates. QLQ root exudates were put into the soil of T308, and T308 root exudates into the soil of QLQ. 【Result】The
results showed that there was no significant difference in the growth between QLQ and T308 (P>0.05). The Cd concentration
in stems and leaves of QLQ was significantly lower than that of T308 (P<0.05). In general, the addition of root exudates of
typical varieties had no significant effect on the growth of such two varieties of I. aquatica Forsk. Generally, the addition
of root exudates improved the Cd concentration and Cd accumulation in the stems, leaves and roots of the experimental
varieties of I. aquatica Forsk, and promoted Cd accumulation in plants. This was mainly because that root exudates improved
plants’absorption of Cd from soil. Root exudates of I. aquatica Forsk collected under different Cd concentration treatments
had different effects on plants’Cd accumulation.Root exudates of the low Cd-cultivar QLQ significantly lowered the Cd translocation coefficient of the high-Cd cultivar T308 (P<0.05), with the translocation coefficient being reduced by 30.23%
under 0 mg/L Cd treatment. While root exudates of T308 had no significant effect on the Cd translocation coefficient of QLQ
(P>0.05).【Conclusion】The addition of root exudates promoted Cd accumulation in water spinach, and the low-Cd cultivar
QLQ showed extremely low Cd translocation capacity. |
