Study On The Acidity And Aluminum Effects Of Ginkgo Growth

"U207" even design was used to study the effects of acidity and aluminum (Al) on Ginkgo growth, and to provide a theory which could reduce acidity and Al depression in the Southern China for Ginkgo.1. Acidity and aluminum stress greatly affected the growth of Ginkgo. The F W increment of the plant and the leaves, the total roots length and the water content of Ginkgo all decreased with the acidity and aluminum concentrations elevated.2. At a pH >4.0, low concentrations of Al (0.2 mmol/L) was good for Ginkgo, and it could improve its shape and properties. But high concentrations of Al was toxic to Ginkgo. Results showed that Ginkgo could grow at the concentrations 0.4 mmol/L of Al at pH 5.5 in the experimental conditions.3. Acidity and Al stress also affected the absorption, the transportation and the distribution of Ca and Al in the Ginkgo. At the same pH, when Al concentration was high (0.5~1.2 mmol/L), it not only affected the absorption of Ca and Al, but also greatly restrained their transportation to the shoots. Therefore, Ca and Al accumulated in the roots. For example,the Al content in the roots was approximately ten times as in the shoots. But when the seedlings of Ginkgo were treated only by acidity, only the absorption of Ca and Al was affected, acidity had no significant effect on their transportation.4. Roots were the primary and the most seriously toxicant parts. The first symptoms in the new roots were roots contorted, swollen and turned brown. When treated with high concentrations of Al, the roots stopped growing. For the whole roots system, the roots color got dark and the new roots reduced, even died or rotted. And this could affect the growth of shoot. These results suggested that acidity and Al had indirect effects on the shoots.