Understanding allocation to shoot and root growth will require molecular information about which compounds act as signals for the plant nutrient status, and how meristem activity and cellular growth are regulated: Opinion
Tóm tắt
Most previous analyses of shoot-root allocation have investigated correlations between changes in putative signals and shoot-root allocation. It is argued that studies of shoot-root allocation need to be extended to include investigations of mutants with specific lesions in nutrient metabolism, to identify the compounds that are sensed as indicators for the plant nutrient status and act as the starting point for specific transduction pathways. The mechanisms of nutrient sensing can then be investigated using molecular and genetic strategies analogous to those that have been successfully used to investigate other signal transduction events. Investigations of shoot-root allocation should also pay more attention to the way in which root architecture is modified in response to nutrient supply, and need to be designed and interpreted in the light of molecular and genetic analyses of root development.
Tài liệu tham khảo
Beck E 1996 Regulation of the shoot/root ratio by cytokinins in Urtica dioca: Opinion. Plant Soil 185, 3–12.
Bloom A J, Chapin F S and Mooney H A 1985 Resource limitation in plants. Annu. Rev. Ecol. Syst. 16, 363–392.
Boerjan W, Cervera M-T, Delarue M, Beeckman T, Dewitte W, Bellini C, Caboche M, Van Onckelen H and van Montagu J 1995 Superroot, a recessive mutation in Arabidopsis confers auxin overproduction. Plant Cell 7, 1405–1419.
Brouwer R 1962 Nutrient influences on the distribution of the dry matter in plants. Neth. J. Agric. Sci. 10, 399–408.
Buysse J, Smolders E and Merkx R 1995 The role of free sugars and amino acids and its regulations of biomass allocation and plant growth. Plant Soil 155, 191–194.
Celenza J L Jr, Grisafi P L and Fink G R 1995 A pathway for lateral root formation in Arabidopsis thaliana. Genes Dev. 9, 2131–2142.
Cheeseman J M, Barreiro R and Lexa M 1996 Plant growth modelling and the integration of shoot and root activities without communicating messengers. Plant Soil 185, 51–64.
Cooper H D and Clarkson D T 1989 Cycling of amino-nitrogen and other nutrients between the shoots and roots in cereals: a possible mechanism integrating shoot and root in regulation of nutrient uptake. J. Exp. Bot. 480, 753–762.
Drew M C and Saker R C 1975 Nitrate supply and the growth of the seminal root system in barley. II. Localised compensatory changes in lateral root growth and the rates of nitrate uptake when nitrate is restricted to only one part of the root system. J. Exp. Bot. 26, 79–90.
Farrar J 1996 Regulation of root weight ratio is mediated by sucrose: Opinion. Plant Soil 185, 13–19.
Fichtner K, Quick W P, Schulze E-D, Mooney H A, Rodermel S R, Bogorad L and Stitt M 1993 Decreased ribulose-1,5-bisphosphate carboxylase-oxygenase in transgenic tobacco transformed with ‘antisense’ rbcS. V. Relationship between photosynthetic rate, storage strategy, biomass allocation and vegetative plant growth at three different nitrogen supplies. Planta 190, 1–9.
Grime J P, Campbell BD, Mackey J M L and Crick J C 1991 Root plasticity, nitrogen capture and competitive ability. In Plant Root Growth: An Ecological Perspective. Ed. D Atkinson. pp 381–397. Blackwell Scientific Publications, Oxford, UK.
Hilhorst H W M and Karssen C M 1989 Nitrate reductase independent stimulation of seed germination in Sisymbrium officinale L. (hedge mustard) by light and nitrate. Ann. Bot. (Lond.) 63, 131–137.
Hobbie L and Estelle M 1995 The axr4 auxin-resistant mutants of Arabidopsis thaliana define a gene important for root gravitropism and lateral root initiation. Plant J. 7, 211–220.
Lambers H 1983 The ‘functional equilibrium’: nibbling on the edges of a paradigm. Nether. J. Agric. Sci. 31, 305–311.
Munns R and Cramer G R 1996 Is coordination of leaf and root growth mediated by abscisic acid? Plant Soil 185, 33–49.
Scheible W-R, Lauerer M, Schulze E-D, Caboche M and Stitt M 1997a Accumulation of nitrate in the shoot acts as a signal to regulate shoot-root allocation in tobacco. Plant J. 11, 671–691.
Scheible W-R, Gonzales-Fontes A, Lauerer M, Müller-Röber B, Caboche M and Stitt M 1997b Nitrate acts as a signal to induce organic acid metabolism and repress starch metabolism in tobacco. Plant Cell 9, 783–798.
Simons C, Migliaccio F, Masson P, Caspar T and Soll D 1995 A novel root gravitropism mutant of Arabidopsis thaliana exhibiting altered auxin physiology. Physiol. Plant. 93, 970–978.
Webster B D and Radin J W 1972 Growth and development of cultured radish tips. Am. J. Bot. 59, 744–751.
Van der Werf A and Nagel O W 1996 Carbon allocation to shoots and roots in relation to nitrogen supply is mediated by cytokinins and sucrose: Opinion. Plant Soil 185, 21–32.
Zhang H M and Forde B G 1998 An Arabidopsis MADS box gene that controls nutrient-induced changes in rooot architecture. Science 279, 407–409.