Summary
Discs from young spinach leaves show a 50-fold increase in fresh weight and a 10-fold increase in chlorophyll over 7 days when cultured in high intensity white light (6.5 mWcm−2). In darkness the increase in fresh weight is 10-fold while chlorophyll decreases. Discs from mature spinach leaves show only a 2-fold increase in fresh weight and a marked decrease in chlorophyll content when cultured for 7 days either in light or darkness. Loss of chlorophyll in cultured discs is closely correlated with leaf and cell age and is affected positively by temperature.
In cultural regimes in which there is a loss of chlorophyll from mature discs chloroplast degeneration occurs. However, degeneration of the cytoplasm does not necessarily occur at the same time as chloroplast breakdown. Chloroplast degeneration involves the loss of thylakoid membranes accompanied with a build up of osmiophilic droplets and membrane bound crystals similar in appearance to fraction I protein. In high intensity light loss of plastid structure occurs within 4 days, but in darkness much of the thylakoidal membrane system persists for as long as 7 days.
Chloroplast formation occurs when discs from mature leaves are cultured in low intensity white light (0.2 mWcm−2). Chloroplast formation in these discs is associated with new cell formation and occurs in callus cells which are mainly formed at vein endings. Three different plastid types were observed in callus cells. It is suggested that chloroplast degeneration in mature leaf discs may be a consequence of these tissues not containing or having access to substances produced by either dividing or expanding cells.
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References
Arnon, D. I., 1949: Copper enzymes in isolated chloroplasts. Polyphenoloxidase inBeta vulgaris. Plant Physiol.24, 1–15.
Bottger, M., 1970: Die hormonale Regulation des Blattfalls beiColeus rheneltianus Berger. Die natürliche Rolle von Abscissinsäure im Blattfallprozeß. Planta93, 205–213.
Bottrill, D. E., J. V. Possingham, andP. E. Kriedemann, 1970: The effect of nutrient deficiencies on photosynthesis and respiration in spinach. Plant and Soil32, 424–438.
Cran, D. G., andJ. V. Possingham, 1972 a: Variation of plastid types in spinach. Protoplasma74, 345–356.
— —, 1972 b: Two forms of division profile in spinach chloroplasts. Nature235, 142.
Dennis, D. T., M. Stubbs, andT. P. Coultate, 1967: The inhibition of brussel sprout leaf senescence by kinins. Canad. J. Bot.45, 1019–1024.
De Ropp, R. S., 1947: Studies in the physiology of leaf growth. IV. The growth and behaviourin vitro of dicotyledenous leaves and leaf fragments. Ann. Bot. N. S.11, 439–447.
Edelman, J., andA. I. Schoolar, 1969: Light as a major factor in chlorophyll destruction. Z. Pflanzenphysiol. Bd.60, 470–471.
Fletcher, R. A., andD. J. Osborne, 1965: Gibberellin as a regulator of protein and ribonucleic acid synthesis during senescence in leaf cells ofTaraxacum officinale. Canad. J. Bot.44, 739–745.
Gerola, F. M., etG. Dassú, 1960: L'evoluzione die chloroplasti durante l'inverdimento sperimentale di frammenti di tuben di Topinambour (Helianthus tuberosus). Nuovo G. bot. ital.67, 63–78.
Israel, H. W., andF. C. Steward, 1967: The fine structure and development of plastids in cultured cells ofDaucus carota. Ann. Bot.31, 1–18.
Jones, R. L., andI. D. J. Phillips, 1966: Organs of gibberellin synthesis in light grown sunflower plants. Plant Physiol.41 (Suppl.), 1ix.
Kawashima, N., andS. G. Wildman, 1970: Fraction I protein. Ann. Rev. Plant Physiol.21, 325–358.
Lewington, R. J., M. Talbot, andE. W. Simon, 1967: The yellowing of attached and detached cucumber cotyledons. J. Exp. Bot.18, 526–534.
Osborne, D. J., 1959: Controls of leaf senescence by auxins. Nature183, 1459–1460.
—, 1962: Effect of kinetin on protein and nucleic acid metabolism inXanthium leaves during senescence. Plant Physiol.37, 595–602.
Possingham, J. V., andW. Saurer, 1969: Changes in chloroplast number during leaf development in spinach. Planta86, 186–194.
—, andJ. W. Smith, 1972: Factors affecting chloroplast replication in spinach. J. Exp. Bot.23, 1052–1059.
Saurer, W., andJ. V. Possingham, 1970: Studies on the growth of spinach leaves (Spinacea oleracea). J. Exp. Bot.21, 151–158.
Shaw, M., andM. S. Manocha, 1965: Fine structure in detached, senescing wheat leaves. Canad. J. Bot.43, 747–755.
Sheldrake, A. R., andD. H. Northcote, 1968 a: The production of auxin by autolysing tissues. Planta80, 227–236.
— —, 1968 b: The production of auxin by tobacco internode tissues. New Phytol.67, 1–13.
Skene, K. G. M., 1970: The relationship between the effects of CCC on root growth and cytokmin levels in the bleeding sap ofVitis vinifera L. J. Exp. Bot.21, 418–431.
Stetler, D. A., andW. M. Laetsch, 1969: Chloroplast development inNicotiana tabacum “Maryland Mammoth”. Amer. J. Bot.56, 260–270.
Tulett, A. J., V. Bagshaw, andM. M. Yeoman, 1969: Arrangement and structure of plastids in dormant and cultured tissue from artichoke tubers. Ann. Bot.33, 217–226.
Woolhouse, H. W., 1969: The nature of senescence in plants. In: Aspects of the biology of ageing. XXIst Symposium of the society for experimental biologists; pp. 179–213, Cambridge: Univ. Press.
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Cran, D.G., Possingham, J.V. The effect of cell age on chloroplast structure and chlorophyll in cultured spinach leaf discs. Protoplasma 79, 197–213 (1974). https://doi.org/10.1007/BF02055789
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DOI: https://doi.org/10.1007/BF02055789