Biochemical Aspects of Parasitism by the Angiosperm Parasites: Host-parasite Interrelationship in Phosphatase Activity

Infection by Cuscuta and Orobanche causes significant losses in dry solids and protein content in host plant or plant part. Changes occur in phosphatase activity towards fructose-1,6-diphosphate at alkaline pH and β-glycerophosphate at acid pH, expressed per mg protein or g fresh tissue. The leaves of all hosts infected by Orobanche show an increase in the alkaline fructosediphosphatase activity, whereas as far as the infection by Cuscuta is concerned the general response is a decrease in the enzyme in the shoots. The alterations in the phosphatase activity towards β-glycerophosphate at acid pH in the shoots are not consistent. However, there is a marked increase in the acid phosphatase activity against β-glycerophosphatase in the roots of the infected hosts. The significance of these findings has been discussed in the light of host-parasite interrelationship.