Effect of Powdery Mildew Infection on Photosynthesis by Leaves and Chloroplasts of Sugar Beets 1

AUTOR(ES)

Magyarosy, Andrew C.

RESUMO

Chloroplasts isolated from powdery mildew-infected (Erysiphe polygoni DC) sugar beet leaves (Beta vulgaris L) showed a reduction in the rate of electron transport and in the accompanying ATP formation in noncyclic photophosphorylation (water as electron donor, NADP as electron acceptor) and little or no change in the rate of ATP formation in cyclic photophosphorylation catalyzed by phenazine methosulfate. The inhibition of noncyclic photophosphorylation appeared to lead in the parent leaves to a decreased rate of photosynthetic CO2 assimilation and a shift in products resulting in a relative increase of amino acids. These changes were accompanied by alterations in chloroplast ultrastructure and by a reduction in the activity of enzymes necessary for the formation of organic acids (phosphoenolpyruvate carboxylase and malate dehydrogenase). These results are similar to the findings of Montalbini and Buchanan (1974 Physiol. Plant Pathol. 4: 191-196) with chloroplasts from rust-infected Vicia faba leaves.

Documentos Relacionados

• Effects of Calcium on the Photosynthesis of Intact Leaves and Isolated Chloroplasts of Sugar Beets 1
• Effects of Sulfur on the Photosynthesis of Intact Leaves and Isolated Chloroplasts of Sugar Beets 1
• Effects of Powdery Mildew Infection on the Efficiency of CO2 Fixation and Light Utilization by Sugar Beet Leaves
• Germin Gene Expression Is Induced in Wheat Leaves by Powdery Mildew Infection.
• Respiratory changes in barley leaves produced by single colonies of powdery mildew 12