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              Printable Handouts
Navigable Slide Index
- Introduction
 - Senescence definition
 - Senescence is universal
 - Selective senescence death
 - Senescence limits resource capture
 - Photosynthesis during grass leaf senescence
 - Senescence is important for recycling
 - Nitrogen during maize ear leaf senescence
 - Senescence as an adaptation to stress
 - Tactical and strategic senescence
 - Senescence and fitness
 - An environmental challenge at the wrong time
 - Senescence and cellulat transdifferentiation
 - The plastid differentiation network (1)
 - Senescence and autolysis
 - The plant cell vacuole
 - The chloroplast to gerontoplast transition
 - Characteristic metabolism of the gerontoplast
 - Chlorophyll catabolism
 - Chlorophyll and its breakdown
 - Chlorophyll colour lost during senescence
 - Pathway of chlorophyll catabolism in senescence
 - Breakdown of proteins
 - Plastids as a source of abundant proteins
 - Regulation of proteins during senescence
 - Recycling amino nitrogen
 - Interconversions of amino acids
 - Gluconeogenesis
 - Glyoxylate cycle and the reversal of glycolysis
 - Stress defences
 - New pigments and chemistry in senescing leaves
 - The pathways of phenolic metabolism
 - Genetics and molecular biology of gerontoplasts
 - Gerontoplast mutants and genetic variants
 - Cosmetic stay-green phenotype
 - Functional stay-green phenotype
 - Expression of senescence genes
 - Functional classes of SAGs
 - Genomics of senescence
 - Visualisation of gene chip patterns
 - Genevestigator expression profile
 - RNAi knockout of At4g22920 in Arabidopsis
 - Manipulation of the transition to gerontoplast
 - Altering senescence by transposon mutagenesis
 - Cytokinin - an inhibitor of plastid senescence
 - Ethylene - a promoter of plastid senescence
 - Applied genetics of plastid senescence
 - The relationship of senescence to yield in wheat
 - Molecular breeding for stress tolerance
 - Reversibility of plastid senescence
 - Tobacco leaf senescence and re-greening
 - The plastid differentiation network (2)
 - Chloro/geronto/chromoplast interrelationships
 - Plastid senescence in unicellular algae
 - Gerontoplasts predate chromoplasts in evolution
 - Floral parts and fruit tissues with chromoplasts
 - The plastid differentiation network (3)
 - Summary
 - Further reading
 
Topics Covered
- Critical role of senescence in plant growth, development, survival and adaptation
 - The senescing chloroplast (gerontoplast) as a phase of plastid differentiation
 - New biochemistry and gene expression in the chloroplast-to-gerontoplast transition
 - Reversibility, manipulation and exploitation of plastid senescence
 - Evolutionary origins of plastid senescence
 
Talk Citation
Thomas, H. (2007, October 1). Plastid senescence [Video file]. In The Biomedical & Life Sciences Collection, Henry Stewart Talks. Retrieved November 4, 2025, from https://doi.org/10.69645/OBCL8902.Export Citation (RIS)
Publication History
Financial Disclosures
- Prof. Howard Thomas has not informed HSTalks of any commercial/financial relationship that it is appropriate to disclose.