Biochemical Adaptations to Anoxia in Barnyard Grass
Although higher plants require oxygen for growth, they frequently experience low oxygen environments which occur in natural wetlands and during flooding or irrigation. Plants tolerate these conditions for only a short period of time before irreversible damage occurs. We have been studying a group of rice weeds which, like cultivated rice (Oryza sativa), can germinate and grow without oxygen. Echinochloa crus-galli var. oryzicola (hereafter oryzicola) metabolizes its seed reserves under N2 and produces a larger seedling from a smaller seed than rice (Kennedy, Rumpho and VanderZee, 1983b). In response to temperature, oryzicola and rice exhibit similar germination characteristics under aerobic conditions. Under anaerobic conditions, however, oryzicola germinates better and tolerates colder temperatures than rice. Thus, both Echinochloa and rice provide excellent opportunities to study metabolic adaptations to low oxygen stress. In addition, the Echinochloa ‘complex’ is composed of several species that differ in their ability to germinate under anoxia (Kennedy et al., 1983b), each exhibiting a full range of habitat preference and weediness in rice cultivation — an ideal natural system for comparative studies on the biochemistry of these important weed species.
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- apRees, T. (1980) Assessments of the contributions of metabolic pathways to plant respiration. In P. Stumpf and E.E. Conn (eds), The Biochemistry of Plants, Vol. 3, Academic Press, New York, pp. 1–29Google Scholar
- Bewley, J.D. and Black, M. (1978) Physiology and Biochemistry of Seeds, Vol. 1. Springer-Verlag, New YorkGoogle Scholar
- Cobb, B.G. and Kennedy, R.A. (1987) Distribution of alcohol dehydrogenase in roots and shoots of rice (Oryza satira). Plant, Cell & Environ. (In press)Google Scholar
- Everard, J.E. and Kennedy, R.A. (1985) Physiology of lipid metabolism during anaerobic germination of Echinochloa crusgalli var. oryzicola. Plant Physiol., 77, S-98Google Scholar
- Gambrell, R.P. and Patrick, W.H. Jr (1978) Chemical and microbiological properties of anaerobic soils and sediments. In D.D. Hook and R.M.M. Crawford (eds) Plant life in anaerobic environments, Ann Arbor Science Publ., Ann Arbor, pp. 375–421Google Scholar
- Kennedy, R.A., Barrett, S.C.H., VanderZee, D. and Rumpho, M.E. (1980) Germination and seedling growth under anaerobic conditions in Echinochloa crus-galli (barnyard grass). Plant Cell Environ., 3, 243–8Google Scholar
- Kennedy, R.A., Rumpho, M.E. and Fox, T.C. (1986) Germination physiology of rice and rice weeds: Metabolic adaptations to anoxia. In R.M.M. Crawford (ed.), Plant life in aquatic and amphibious habitats, British Ecol. Soc. Special Symposium, Blackwell, Oxford (in press)Google Scholar
- Lance, C., Chauveau, M. and Dizengremel, P. (1985) The cyanide-resistant pathway of plant mitochondria. In R. Douce and D.A. Day (eds), Encyclopedia of plant physiology , New Series, Vol. 18, Springer-Verlag, New York, pp. 202–47Google Scholar
- Pradet, A and Bomsel, J.L. (1978) Energy metabolism in plants under hypoxia and anoxia. In D.D. Hook and R.M.M. Crawford (eds), Plant life in anaerobic environments, Ann Arbor Science Publ., Ann Arbor, pp. 89–118Google Scholar
- Roberts, J.R.M. (1985) Uses of high resolution 31P nuclear magnetic resonance spectroscopy to study metabolism in living plant tissues. In D.D. Randall, D.G. Blevins and R.L. Larson (eds), Current topics in plant biochemistry and physiology, Vol. 4, University of Missouri-Columbia Press, Columbia, MO, pp. 207–17Google Scholar
- Rumpho, M.E. and Kennedy, R.A. (1983b) Activity of the pentose phosphate and glycolytic pathways during anaerobic germination of Echinochloa crus-galli (barnyard grass). J. Exp. Bot., 155, 1–7Google Scholar
- Vartapetian, B.B. (1978) Structure and function of mitochondria from rice coleoptiles grown under strictly anaerobic conditions. In G. Ducet and C. Lance (eds), Plant mitochondria, Elsevier/North Holland Biomedical Press, Amsterdam, pp. 411–18Google Scholar