Respiratory Metabolism of Amitrole-induced Aplastidic Mesophyll Cells of Canna edulis Ker.

Sublethal concentration of amitrole (3-amino- 1, 2, 4-triazole) spray induced albinism in the young leaves of Conna edulis Ker. The bleached (aplastidic) mesophyll cells were devoid of well developed plastids. Amitrole treatment induced an enhanced rate of 0₂ uptake of the treated leaves in the initial stages. The inhibition in the rate of oxygen uptake of aplastidic cells was to the tune of 14% when compared to that of green cells. The cellular mitochondrial function of these cells was intact and more active than the green cells as measured by enhanced 0₂ uptake to the externally added glucose and succinate. The aplastidic cells did not exhibt complete dependence on external substrates, indicating probably that the levels of endogenous substrates were only marginally limiting.