Exploitation of localized phosphorus-patches by common bean roots

Snapp, Sieglinde S.; Lynch, Jonathan P.

doi:10.1007/bf00010127

Cited by 43 publications

(26 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus, for example, an external supply of 1 mM NO 3 − stimulated lateral root growth more strongly in barley when the remainder of the root system was in low NO 3 − than if it too was in high NO 3 − (Drew et al, 1973). Similarly, roots of P-stressed bean plants presented with a P-enriched soil patch branched more intensively within the patch than did roots of unstressed plants (Snapp et al, 1995).…”

Section: Root Growth and Branchingmentioning

confidence: 89%

The nutritional control of root development

Forde

Lorenzo

2002

Interactions in the Root Environment: An Integrated Approach

221

254

View full text Add to dashboard Cite

Root development is remarkably sensitive to variations in the supply and distribution of inorganic nutrients in the soil. Here we review examples of the ways in which nutrients such as N, P, K and Fe can affect developmental processes such as root branching, root hair production, root diameter, root growth angle, nodulation and proteoid root formation. The nutrient supply can affect root development either directly, as a result of changes in the external concentration of the nutrient, or indirectly through changes in the internal nutrient status of the plant. The direct pathway results in developmental responses that are localized to the part of the root exposed to the nutrient supply; the indirect pathway produces systemic responses and seems to depend on long-distance signals arising in the shoot. We propose the term 'trophomorphogenesis' to describe the changes in plant morphology that arise from variations in the availability or distribution of nutrients in the environment. We discuss what is currently known about the mechanisms of external and internal nutrient sensing, the possible nature of the long-distance signals and the role of hormones in the trophomorphogenic response.Abbreviations: ABA, abscisic acid; NR, nitrate reductase; P i , inorganic phosphate

show abstract

Section: Root Growth and Branchingmentioning

confidence: 89%

The nutritional control of root development

Forde

Lorenzo

2002

Interactions in the Root Environment: An Integrated Approach

221

254

View full text Add to dashboard Cite

show abstract

“…Many authors have measured the structural response of root systems to the levels of nutrient that is available to them [15], [35], [114], [106]. The majority find that an increase in phosphate level leads to the first order root branch density increasing in order to exploit the soil more effectively, but the root length is generally thought to be less affected by the nutrient level in the soil [15].…”

Section: Root Structure In Relation To Nutrient Uptakementioning

confidence: 99%

“…The majority find that an increase in phosphate level leads to the first order root branch density increasing in order to exploit the soil more effectively, but the root length is generally thought to be less affected by the nutrient level in the soil [15]. However, some studies [35], [114] have found that the length is also affected.…”

Section: Root Structure In Relation To Nutrient Uptakementioning

confidence: 99%

A mathematical model of plant nutrient uptake

Koebernick¹,

Fowler²,

Darrah

2001

Journal of Mathematical Biology

111

159

View full text Add to dashboard Cite

This thesis deals with the mathematical modelling of nutrient uptake by plant roots. It starts with the Nye-Tinker-Barber model for nutrient uptake by a single bare cylindrical root. The model is treated using matched asymptotic expansion and an analytic formula for the rate of nutrient uptake is derived for the first time. The basic model is then extended to include root hairs and mycorrhizae, which have been found experimentally to be very important for the uptake of immobile nutrients. Again, analytic expressions for nutrient uptake are derived. The simplicity and clarity of the analytical formulae for the solution of the single root models allows the extension of these models to more realistic branched roots. These models clearly show that the "volume averaging of branching structure" technique commonly used to extend the Nye-Tinker-Barber with experiments can lead to large errors. The same models also indicate that in the absence of large-scale water movement, due to rainfall, fertiliser fails to penetrate into the soil. This motivates us to build a model for water movement and uptake by branched root structures. This model considers the simultaneous flow of water in the soil, uptake by the roots, and flow within the root branching network to the stems of the plant. The water uptake model shows that the water saturation can develop pseudo-steadystate wet and dry zones in the rooting region of the soil. The dry zone is shown to stop the movement of nutrient from the top of the soil to the groundwater. Finally we present a model for the simultaneous movement and uptake of both nutrients and water. This is discussed as a new tool for interpreting available experimental results and designing future experiments. The parallels between evolution and mathematical optimisation are also discussed.

show abstract

“…Surprisingly little attention however has been given to the latter process, and in only one previous study (Schwartz et al, 1999) has the possibility that the root growth of hyperaccumulator plants may respond positively to metal enriched soil been examined. Active foraging for the macronutrients nitrogen and phosphorus, by means of enhanced root growth and root branching in nutrient enriched patches, has been demonstrated in many species (Drew & Saker, 1975 ;Granato & Raper, 1989 ;Gross et al, 1993 ;Snapp et al, 1995), and is reviewed in detail by Robinson (1994). Indeed, Zhang & Forde (1998) have identified a gene (ANR1) which encodes for increased lateral root proliferation in localized patches of nitrate (NO $ − ).…”

Section: mentioning

confidence: 99%

Positive responses to Zn and Cd by roots of the Zn and Cd hyperaccumulator Thlaspi caerulescens

et al. 2000

View full text Add to dashboard Cite

The effects of localized zinc (ZnO) and cadmium (CdS) enrichment on the allocation of root biomass, root length and partitioning of current assimilate within root systems of the Zn hyperaccumulator Thlaspi caerulescens were investigated using a rhizobox system. The rhizoboxes contained either homogeneous soil or juxtaposed control and metal-enriched soil. In the heterogeneous treatments the Zn-enriched soil contained 250, 500 or 1000 mg Zn kg −" . The plants consistently allocated c. 70% of their total root biomass and length into the metal-enriched soil. Moreover, 70% of the current assimilate ("%C) allocated to the roots was localized in the Zn-enriched soil of the heterogeneous treatments. The concentration of Zn (250-1000 mg kg −" ) in the enriched soil had no effect on these patterns of root allocation, nor were there significant effects of the Zn treatments on the total root or shoot biomass of the plants. The positive responses to the localized metal treatments were therefore characterized by a concomitant reduction in root allocation into the control soil. In contrast to T. caerulescens, when grown with juxtaposed control and Zn-enriched soil the non-accumulator Thlaspi arvense showed reduced root allocation into a patch enriched with 500 mg kg −" Zn. In a further experiment, two populations of T. caerulescens that differ in their abilities to accumulate Cd were grown with juxtaposed control and Cd-enriched soil. The plants from a population that accumulated Cd also showed increased root biomass and root length allocation into the Cdenriched soil. Plants from the population that did not accumulate Cd showed no such increase. The possibility that T. caerulescens forages for metals, and the precision of its root allocation with respect to localized metal enrichment is highlighted. The significance of these findings for the selection of hyperaccumulator plants for use in the phytoextraction of Zn and Cd from mine spoils (phytomining) and the phytoremediation of heterogeneous contaminated soils are discussed.

show abstract

Exploitation of localized phosphorus-patches by common bean roots

Cited by 43 publications

References 30 publications

The nutritional control of root development

The nutritional control of root development

A mathematical model of plant nutrient uptake

Positive responses to Zn and Cd by roots of the Zn and Cd hyperaccumulator Thlaspi caerulescens

Contact Info

Product

Resources

About