A Spatial Analysis of Physiological Changes Associated with Infection of Cotyledons of Marrow Plants with Cucumber Mosaic Virus

• Published in: Plant physiology (Bethesda) Vol. 111; no. 4; pp. 975 - 985
• Main Authors: László I. Técsi, Smith, Alison M., Maule, Andrew J., Leegood, Richard C.
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01-08-1996
• Subjects: Biological and medical sciences; Capsid proteins; Chlorophylls; Cotyledons; Dehydrogenases; Enzymes; Fundamental and applied biological sciences. Psychology; Generalities. Techniques. Transmission, epidemiology, ecology. Antiviral substances, control; Infections; Lesions; Phytopathology. Animal pests. Plant and forest protection; Plant viruses and viroids; Plant-Microbe and Plant-Insect Interactions; Plants; Starches; Viruses; Cotyledon; Virus multiplication; Plant pathogen; Starch; Cucurbitaceae; Spatial analysis; Host agent relation; Cucurbita pepo; Metabolism; Virus; Vegetable crop; Enzymatic activity; Dicotyledones; Cucumber mosaic virus; Angiospermae; Bromoviridae; Glycolysis; Cucumovirus; Spermatophyta; Localization; Photosynthesis; Cell respiration
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.111.4.975

Changes in host primary metabolism associated with the compatible interaction between cucumber mosaic virus and cotyledons of the marrow plant (Cucurbita pepo L.) have been localized, first by measuring activities of key enzymes in infected and uninfected regions of the cotyledon, and second by histochemical techniques applied to tissue prints of the infected region. A series of progressive metabolic changes occurs within the expanding infected lesion. Virus replication and the synthesis of viral protein at the periphery creates a strong sink demand associated with increased activities of anaplerotic enzymes, increased photosynthesis, and starch accumulation. Inside the lesion, when the synthesis of virus has declined, photosynthesis is reduced, starch is mobilized, and the emphasis of metabolism is shifted toward glycolysis and mitochondrial respiration. These changes are associated spatially with the onset of chlorosis. A decrease in total protein synthesis in this inner zone could be instrumental in some or all of these changes, leading to symptoms of viral infection.