RESPIRATION AND TERMINAL OXIDASES OF XIPHINEMA INDEX

Abstract

Active specimens of Xiphinema index showed a respiratory activity markedly influenced by the pH of the assay mixture. The optimum for nematode respiration was pH 7. Sodium azide severely inhibited the oxygen uptake of the nematodes but it did not kill them. Homogenates of nematodes actively oxidized succinate and ascorbate. Sodium azide showed a partial inhibition by the hydroxamic acid m-CLAM and the enzyme SOD. Conversely, duroquinol oxidation was inhibited by the sole m-CLAM whilst SOD showed very little effect. LDH activity was found in X. index homogenates to be 3-fold higher than in Meloidogyne hapla and Heterodera schachtii homogenates.