Effects of potassium on Pb uptake by rice under sterile condition.

The present study was carried out to study the effects of different Pb levels on rice growth and different K levels on Pb uptake by rice(at 100mg / L Pb) under sterile condition.The results showed that plant height,root length,dry weight and the chlorophyll content were decreased with increasing Pb concentration.The activity of POD increased initially and then decreased with increase in Pb concentration,while the content of Pb in rice plant was increased.When the concentration of Pb was 100ml / L in medium,plant height,root length,dry weight and the content of chlorophyll were increased with increasing potassium concentration,while the activity of POD and the Pb content in plant decreased.The Pb content was the lowest when the concentration of potassium reahed 200mg / L.It was concluded that potassium could increase the stress resistance of rice under low concentration of Pb in medium.At the same time,potassium could decrease the uptake and accumulation of Pb in rice.