Enzymatische Charakteristik der Entwicklungsphasen des Getreide-Primärblattes im Hinblick auf funktionelle Beziehungen zwischen Nitratreduktion und anderen Stoffwechselwegen1)1)Herrn Prof. Dr. Drs. h. c. K. Mothes aus Anlaß der 75. Wiederkehr seines Geburtstages in Verehrung gewidmet.
1975; Elsevier BV; Volume: 167; Issue: 6 Linguagem: Inglês
10.1016/s0015-3796(17)31307-0
ISSN0015-3796
AutoresJohannes‐Günter Kohl, G. Dudel, M. Apel,
Tópico(s)Potato Plant Research
ResumoSummary Changes of activity of nitrate reductase, glycerate dehydrogenase, triosephosphate isomerase, malate dehydrogenase, isocitrate dehydrogenase and shikimate dehydrogenase were investigated in different parts of primary leaves of wheat and barley during leaf development. Nitrate reductase and glycerate dehydrogenase show marked changes in activities. The maximum of activity shifts basipetally during leaf development. This is due to the different physiological ages of cells in different parts of the leaves. Nitrate reductase exhibits its maximum of activity during the phase of growing and a suppression occurs before full activity of the photosynthetic apparatus appears. Maximum of activity of shikimate dehydrogenase occurs in the earliest stages of cell development. Triosephosphate isomerase, malic and isocitric dehydrogenases only exhibit small changes in activity; the apical leaf section, however, shows an increase in activity of malate and isocitrate dehydrogenases due to yellowing. These senescence characteristics can be prevented by the application of kinetin. Kinetin partly prevents the decrease of nitrate reductase but a subsequent increase of its activity is observed. The results are discussed with respect to the enzymatic characteristics of developmental phases of leaf cells and in relation to the main physiological processes, i. e. growth, photosynthesis, photorespiration and respiration.
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