Effect of cations and p on the mobility of zinc 65 in plants

The effects of Ca,Mg,Fe,Cu,K and P on the absorption and translocation of 65Zn in maize and wheat plants were studied in Arnon and Hoagland's nutrient solution. The absorption of 65Zn differed in maize and wheat and also depends on the age of plants. More than 75% of the total activity assimilated by the plants remained in the root and less than 10% of the assimilated activity was translocated to the leaf. More zinc was translocated to the aerial parts in wheat than in maize. The presence of Ca,Mg,K,Mn,Cu,Fe and P hindred the absorption and translocation of 65Zn significantly in 31 days old maize plants while in 16 days maize and 30 days wheat, the inhibitory effect was conspicuous but not satistically significant. The translocation of 65Zn to the aerial part of maize plants was almost negligible in Ca,Mg,K and Cu treatments. These cations also inhibited the absorption of zinc by the roots. The inhibitory effect of different ions was found to be associated with the high mineral status of the dry matter of plant tissues. (author)