Effect of Soaking with Acid and Aluminum on Seed Germination and Seedling Growth of Raphanus sativus

Effects of soaking with different acid and aluminum(Al) stress on seed germination and seedling growth of radish(Raphanus sativus) were investigated.The results showed that medium intensity of acid and Al stress(pH≤4.5,Al concentration 100 to 1 000 μmol/L) did not have significant influence on seed germination,while had significant positive influence on germination power,germination index,vigor index,and negative influence on seedling growth such as root,stem and seedling length,root and aboveground fresh weight.In the low concentrations of Al treatments(0 to 10 μmol/L),the seedling growth increased firstly and then decreased with pH value changing from 5.5 to 3.5.In the medium and high concentrations of Al treatments(100 to 5 000 μmol/L),the seedling growth decreased with the decreasing of pH value.While the seedling growth showed a decreased trend with increasing of Al concentrations,especially for root,thus root was the most sensitive part.These results indicated that radish seed germination period was more tolerant to acid and Al stress than seedling growth.When pH value was under 4.5,the Al concentration was 1 000 μmol/L,which could significantly inhibit the seedling growth of radish.