Light activation of enzymes in relation to leaf age inVigna unguiculata (L.) Walp andZea mays L.
- 15 Downloads
The effects of light-dark transition and aplastidic condition by the photobleaching herbicide, 3-amino-1,2,4-triazole, on the activities of enzymes likein vivo nitrate reductase, peroxidase, polyphenol oxidase and catalase were studied in leaves of different ages of 30-day old plants ofVigna unguiculata andZea mays. The activity of nitrate reductase was found to be higher in young leaves and showed a gradual decline at the time of maturity and senescence. In amitrole-bleached young leaves,in vivo nitrate reductase activity was significantly reduced. Although peroxidase is a light-activated enzyme, the enzyme was more active only in fully mature and senescing leaves ofVigna unguiculata. InZea mays, peroxidase activity was more in mature leaves compared to senescent leaves. Interesting feature of this enzyme was that its activity increased upon dark treatment inVigna unguiculata. A similar trend was also observed in polyphenol oxidase activity in mature and senescent leaves ofVigna unguiculata andZea mays. Foliar spray of amitrole increased peroxidase and polyphenol oxidase activities in the young leaves ofZea mays andVigna unquiculata. The results are discussed in relation to age of leaves and the presence or absence of leaf plastids.
KeywordsNitrate reductase peroxidase catalase Zea mays polyphenol oxidase amitrole Vigna unguiculata
Unable to display preview. Download preview PDF.
- Aaronson S 1960 Mode of action of aminotriazole on photosynthetic microorganisms;J. Protozool. 7 289–294Google Scholar
- Burstrom H 1943 Photosynthesis and assimilation of nitrate by wheat leaves;Annu. Rev. Agric. Coll. Sweden 2 1–50Google Scholar
- Gnanam A, Govindarajan A G and Vivekanandan M 1974 Interaction between chloroplasts and mitochondria in isolated leaf cells; inProc. Int. Symp. Biomemb., p. 353Google Scholar
- Hisamatsu S, Nihira J, Takeuchi Y, Satoh S and Konde N 1988 NO2 suppression of light-induced nitrate reductase in squash cotyledons;Plant Cell Physiol. 29 395–401Google Scholar
- Johnson H S and Hatch M D 1970 Properties and regulation of leaf nicotinamide-adenine dinucleotide phosphate-malate dehydrogenase and malic enzyme in plants with the C4-dicarboxylic acid pathway of photosynthesis;Biochem. J. 119 283–280Google Scholar
- Malik C P and Singh M B (eds) 1980 Estimation of amylase enzyme; inPlant enzymology and histoenzymology (New Delhi: Kalyani Publishers) pp 4–7Google Scholar
- Mohr H 1986 Control by light of plastidogenesis as part of a control system; inRegulation of chloroplast differentiation (eds) G Akoyunoglou and H Senger (New York: Alan R Liss) pp 623–634Google Scholar
- Sagisaka S and Asada M 1986 Cytochemical evidence for the occurrence in plants of a novel microbody that contains peroxidase;Plant Cell Physiol. 27 1597–1602Google Scholar
- Scheibe R, Wagenpfeil D and Fischer J 1986 NADP-malate dehydrogenase activity during photosynthesis in illuminated spinach chloroplasts;J. Plant Physiol. 124 103–110Google Scholar
- Vivekanandan M and Edwards G E 1987 Light activation of NADP-malate dehydrogenase inPisum sativum L.;Proc. Indian Natl. Sci. Acad. B53 499–504Google Scholar
- Vivekanandan M and Gnanam A 1975b Studies on the mechanism of action of amitrole on chloroplast development;Indian J. Biochem. Biophys. 12 374–378Google Scholar
- Vivekanandan M and Gnanam A 1975c Studies on the effect of amino-triazole on chloroplast development inPhaseolus radiatus L.;Curr. Sci. 44 842–845Google Scholar