Maize root

Lachno, D.R. Baker, D.A. (1986). Stress induction of abscisic acid in maize roots. Physiologia Plantarum, 68, 215-21. 

Fig. 1. SDS gel analysis of proteins synthesised by excised maize roots incubated at continuous 40 °C. Roots of 3-day-old maize seedlings were excised and incubated at 40 °C for increasing times as indicated. Labelling with [ Sjmethionine was carried out in the final 20 min of the incubation. Proteins were visualised by fluorography. Mol wt distribution in kDa indicated at left. From Cooper Ho (1983).

Laszlo, A. St Lawrence, P. (1983). Parallel induction and synthesis of PDC and ADH in anoxic maize roots. Molecular and General Genetics, 192, 110-17. 

Roberts, J.K.M., Callis, J., Wemmer, D., Walbot, V. Jardetzky, O. (1984). Mechanisms of cytoplasmic pH regulation in hypoxic maize root tips and its role in survival under hypoxia. Proceedings of the National Academy of Sciences, USA, 81, 3379-83. 

A more significant body of literature focuses on the use of protoplasts in understanding processes related to stress tolerance. The role of Ca in salt toleranee has been evaluated using maize root protoplasts. Exposure of the plasmalemma directly to external media revealed a non-specific replacement of Ca by salt. Sodium was found to replace Ca though this could be reversed by adding more Ca (Lynch, Cramer Lauchli, 1987). This approach assists in understanding the role of specific ion interaction in enhancing salt tolerance and is potentially applicable to studies on the molecular basis for ion specificity of plant membranes. 

E. Benizri, A. Courtade, C. Picard, and A. Guckert, Role of maize root exudates in the production of auxins by Pseudomonas fluorescens M.3.I. Soil Biol. Biochem. 30 1481 (1998). 

E. A. Curl and B. Truelove, The Rhizosphere, Springer-Verlag, New York, 1986. R. Schonwilz and H. Ziegler, Interaction of maize roots and rhizosphere microorganisms, Z, Pflanzenerniihr. Bodenk. 752 217 (1989),... 

J. L. Morel, L. Habib, S. Plantureux, and A. Guckert, Influence of maize root mucilage on soil aggregate stability. Plant Soil 736 1 II (1991). 

M. E. McCully and J. S. Boyer, The expansion of maize root-cap mucilage during hydration 3. Changes in water potential and water eontent. Phy. iiol. Plant. 99 169 (1997). 

J. Xia and P. H. Saglio, Characterization of the hexose transport system in maize root tips. Plant Physiol 06 1 (1988). 

I. Nir, S. Klein, and A. Poljakoff-Mayber, Effect of moisture stress on submicro-scopic structure of maize roots, Australian Journal of Biological Science 22 1 (1969). 

P. H. Saglio, P. Raymond, and A. Pradet, Metabolic activity and energy charge of excised maize root tips under anoxia control by soluble sugars. Plant Physiology 7 6 l()53 (1980). 

S. Santi, G. Locci, R. Pinton, S. Cesco, and Z. Varanini, Plasma membrane H -ATPase in maize roots induced for NO, uptake. Plant Physiol. 109 1271 (1995). 

G. R. Findenegg and J. A. Nelenians, The effect of phytase on the availability of P from myo-inositol hexaphosphate (phytate) for maize root. Plant Soil 754 189 (1993). 

Figure 2 Gradients in Rb around a maize root as visualized by autoradiography. The depletion of Rb depends on the diffusion coefficient (D,.) which in turn depends on the soil texture. (From Ref. 12.)...

Figure 3 Root-induced changes in pH in an agarose sheet obtained 2 h after embedding a maize root in the gel. Note that while the root lip is making its local rhizosphere more alkaline, the more basal portion is acidifying the rhizosphere. (From Ref. 102.1...

Figure 9 A sensitivity analysis for exudation losses by maize roots. The sensitivity was analyzed by halving and doubling each parameter value in turn while keeping all other parameters at their standard values. Parameters shown on the graph are defined in the text. (From Ref. 55.)...

Figure 12 The predicted changes in average root radius of maize root systems during 20 days of growth. The subscripts on the curves denote differing ways of calculating the average (by volume, by surface area or by root number). (From Ref. 38.)...

L. Pages. M. D. Jourdan, and D. Picard, A simulation model of the three-dimensional architecture of the maize root system. Plant Soil II9 41 (1989). 

Another limitation to the studies in Table 1 is the small number of plant species tested. Primarily monocotyledonous plants have been studied, although McClure et al. (26) found ferulic acid inhibitory in soybean. The restriction of studies to monocots is probably because the mechanism of mineral absorption has been more fully elucidated with monocots. Harper and Balke (32) reported some minor differences in the inhibition of K+ absorption by salicylic acid among oats (Avena sativa L.), wheat (Triticum aestlvum L.), barley, and maize roots. 

Other lipophilic weak acids have been shown to alter PD in plant cells. Benzoic and butyric acids (1 PM) rapidly depolarized the PD In oat coleoptile cells at pH 6.0 to about -100 mV (43). Higher concentrations (10 mM) of butyrate produced hyperpolarization. Butyrate also hyperpolarized apical cortical cells of maize roots... 

Klingner, A., H. Bothe et al. (1995). Identification of a yellow pigment formed in maize roots upon mycorrhizal colonization. Phytochemistry 38(1) 53-55. 

Vierheilig, H., H. Gagnon et al. (2000). Accumulation of cyclohexenone derivatives in barley, wheat and maize roots in response to inoculation with different arbuscular mycorrhizal fungi. Mycorrhiza 9(5) 291-293. 

Brauer D, Uknalis J, Triana R, Tu S-I. Subcellular compartmentation of different fluorescein derivatives in maize root epidermal cells. Protoplasma 1996 192 70-79. 

Sauer A, RobinsonDG. Intracellular localization of posttranslational modifications in the synthesis of hydroxyproline-rich glycoproteins. Peptidyl hydroxylation in maize roots. Planta 1985 164 287-294. 

Some studies indicated that exogenous zearalenone influences plant growth and development. For example, zearalenone stimulated the initiation of the vegetative bud in tobacco pith callus tissue (Mirocha et al. 1968), inhibited the cell membrane transport of maize roots (Vianello and Macri 1981) and enhanced the a-amylase and P-glucosidase activities of germinating maize seeds. 

Vianello A, Macri F (1981) Effect of zearalenone (F-2) on pea stem, maize root, and rat liver mitochondria. Planta 153 443-446... 

Figure 6.3 Aerenchyma development and changes in respiration rate along the length of maize roots grown in anoxic media (adapted from Armstrong et al., 1991a). Reproduced by permission of Backhuys publishers...

Rasmann S, Kollner TG, Degenhardt J, HUtpold 1, Toepfer S, Kuhlmann U, Gershenzon J, Turlings TCJ (2005) Recruitment of entomopathogenic nematodes by insect-damaged maize roots. Nature 434 732-737... 

In maize-root tips, high specific activities of/ -D-galactosidase, a- and jff-D-glucosidase, N-acetyl-/ -D-glucosaminidase, acid phosphatase, and phosphodiesterase (EC 3.1.4.1) are found in the cell-wall fraction.246... 

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