Journal of Experimental Botany, Vol. 52, No. 362, pp. 1883-1891,
September 1, 2001
© 2001 Oxford University Press
Original Papers |
Arbuscular mycorrhizal fungi alter phosphorus relations of broomsedge (Andropogon virginicus L.) plants
Department of Biology, West Virginia University, Morgantown, WV 26506, USA
Broomsedge (Andropogon virginicus L.) is a dominant grass revegetating many abandoned coal-mined lands in West Virginia, USA. Residual soils on such sites are often characterized by low pH, low nutrients, and high aluminium. Experiments were conducted to assess the resistance of broomsedge to limited phosphorus (Pi) availability and to investigate the role that arbuscular mycorrhizal (AM) fungi play in aiding plant growth under low Pi conditions. Pregerminated mycorrhizal and non-mycorrhizal seedlings were grown in a sand-culture system with nutrient solutions containing Pi concentrations ranging from 10 to 100 µM for 8 weeks. Non-mycorrhizal plants exhibited severe inhibition of growth under Pi limitation (<60 µM). Colonization by AM fungi (combined Glomus clarum Nicolson & Schenck and Gigaspora gigantea (Nicol. & Gerd.) Gerd. & Trappe) greatly enhanced host plant growth at low Pi concentrations, but did not benefit growth when Pi was readily available (100 µM). In comparison to non-mycorrhizal plants, mycorrhizal plants had higher phosphorus use efficiency at low Pi concentrations and maintained nearly constant tissue nutrient concentrations across the gradient of Pi concentrations investigated. Manganese (Mn) and sodium (Na) accumulated in shoots of non-mycorrhizal plants under Pi limitation. Mycorrhizal plants exhibited lower instantaneous Pi uptake rates and significantly lower Cmin values compared to non-mycorrhizal plants. These patterns suggest that the symbiotic association between broomsedge roots and AM fungi effectively maintains nutrient homeostasis through changes in physiological properties, including nutrient uptake, allocation and use. The mycorrhizal association is thus a major adaptation that allows broomsedge to become established on infertile mined lands.
Key words: Nutrient use efficiency, nutrient homeostasis, phosphate uptake.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
K. Yi, Z. Wu, J. Zhou, L. Du, L. Guo, Y. Wu, and P. Wu OsPTF1, a Novel Transcription Factor Involved in Tolerance to Phosphate Starvation in Rice Plant Physiology, August 1, 2005; 138(4): 2087 - 2096. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Cumming and J. Ning Arbuscular mycorrhizal fungi enhance aluminium resistance of broomsedge (Andropogon virginicus L.) J. Exp. Bot., May 1, 2003; 54(386): 1447 - 1459. [Abstract] [Full Text] [PDF] |
||||

