Nutritional Balance in Flue-Cured Tobacco

Tejwani, K. G.; Venkatraman, K. V.

doi:10.1097/00010694-195812000-00004

Cited by 4 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The same pattern of behavior is probably true for other plant species which reduce N03 in the tops and in which the cation/ anion uptake ratio is close to unity, ie. sugar beet (22), tobacco (21).…”

mentioning

confidence: 99%

Nitrate Uptake by Roots as Regulated by Nitrate Assimilation in the Shoot of Castor Oil Plants

Kirkby¹,

Armstrong²

1980

Plant Physiol.

View full text Add to dashboard Cite

Ricinus conunwuis was used to test the Ben Zioni-Dijkshoorn hypothesis that NO3 uptake by roots can be regulated by NO3 assimilation in the shoot. The rate of the anion charge from assimilated N03-(and S042-) was followed in its distribution between organic acid anion accumulation and HC03-efflux into the nutrient solution. In plants adequately supplied with NO3-, HC03-efflux accounted for between 56 and 63% of the anion charge. When the plants were subjected to a low NO3 regime HC03-excretion accounted for only 23% of the charge. A comparison of mature plants growing for a 10-day period at the two levels of NO3 nutrition revealed that the uptake of N03-at the higher level was increased 3-fold, whereas K uptake was unaltered. To trace ion movement within the plant, the ionic constituents of xylem and phloem sap were determined. In xylem sap these constituents were found to be predominantly K+, Ca2+, whereas (14,17).Findings consistent with the above mechanism have been presented by a number of authors (4.6, 9). However, unequivocal proof is1lacking that the products of NO3 reduction in upper plant parts can control NO3 uptake by roots. Evidence is needed that charge from NO3 assimilation in the tops is effluxed as HCO3 from the roots, concomitant with K recirculation in the plant. To demonstrate this was the purpose of the present study.In previous publications investigating ionic balance in tomato plants (15, 16) we concluded that in this particular species the control mechanism outlined above was relatively unimportant. This conclusion was reached from studies in which the fate of anion charge arising from the assimilation of N03-and S042-in NO3-fed plants was followed in its distribution between organic anion accumulation in the plant and HCO3 efflux into the nutrient medium (as measured by excess anion over cation uptake). Increasing the level of NO3 nutrition, compensating with s042-, stimulated organic acid anion accumulation in the plant tops, whereas HC03-efflux from the roots represented only a small percentage-at most 20%o-of the assimilated charge. The cation/anion uptake ratios were therefore close to unity and the amount of N03-taken up by exchange for HCO3 derived from N03-reduction (as OH-) was relatively small. It was also inferred from this investigation that the extensive K recirculation as necessitated by the control model did not occur. This was confirmed by subsequent investigations of tomato plants in this laboratory (1). The same pattern of behavior is probably true for other plant species which reduce N03 in the tops and in which the cation/ anion uptake ratio is close to unity, ie. sugar beet (22), tobacco (21).We suggest that the NO3 transport model might be more applicable to plant species in which HCO3 root efflux is dominant with an associated high excess anion over cation uptake. In order to test this idea further we extended our investigations to another plant species. Ricinus communis var. Gibsonii was chosen as it offered the considerable advantage that both xylem and ...

show abstract

mentioning

confidence: 99%

Nitrate Uptake by Roots as Regulated by Nitrate Assimilation in the Shoot of Castor Oil Plants

Kirkby¹,

Armstrong²

1980

Plant Physiol.

View full text Add to dashboard Cite

show abstract

“…These stages of gully growth towards inactivity (stability) have been expressed by several authors around the world but without the reference to cross-sectional shape per se and with and without the reference to cyclicity (e.g., Sobolev, 1948cited in Haigh, 1984Tejwani et al, 1975;Schwab et al, 1981;Dagar, 2018). Boucher (2015) recounts that Downes (1946Downes ( , 1949, working in north-eastern Victoria, Australia, associated the cross-sectional shape of gullies to differences in particular soil characteristics: a 'U'-shaped cross-section was associated with highly erodible, dispersive sodic subsoils whereas 'V'-shaped gullies formed in soils with a high level of aggregate stability and where the subsoils exhibited less sodicity.…”

Section: Gully Cross-sectional Shapementioning

confidence: 99%

“…Many authors have attempted to both classify gullies and define them in some way by different criteria (e.g., Ireland et al, 1939; Schumm, 1956; Frevert et al, 1955; Brice, 1966; Heede, 1970; Hilsky, 1973; De Ploey, 1974; Tejwani et al, 1975; Bradford & Piest, 1980; Imeson & Kwaad, 1980; Schumm et al, 1984; Foster, 1986; Geyik, 1986; Planchon, Fritsch, & Valentin, 1987; Ezechi & Okagbue, 1989; Poesen & Govers, 1990; Poesen & Govers, 1990; Bocco, 1991; Poesen, 1993; Wells, 1996; Casalí et al, 1999; Oostwoud‐Wijdenes & Bryan, 2001; Franklin et al, 2004; Brooks et al, 2009). There is even more than one classification for gullies on Mars (Aston et al, 2011; Aul & Dixon, 2016).…”

Section: What Is a Gully?mentioning

confidence: 99%

“…Essentially it relies on eight parameter criteria to classify ‘ravines’ into five suitability groups (for reclamation). No classification of gully form ( sensu Ireland et al, 1939) is considered for Indian ravines, as the focus is on what is deemed most important for control and reclamation, such as depth, width, and either side‐slope gradient (Tejwani et al, 1975) or channel bed slope (Dagar, 2018; Haigh, 1984; Raj et al, 1999). As such, this parameterized classification (typology) has little relationship to a general‐purpose classification.…”

Section: What Is a Gully?mentioning

confidence: 99%

“…Incisional and erosional land surface features that have commonly been described in different global locations such as arroyos (Cooke & Reeves, 1976), ravines (Dagar, 2018; Haigh, 1984; Tejwani et al, 1975), wadis (Goudie, 2004; Wells, 2004a) may not actually equate to the commonly held understanding of what constitutes a ‘typical’ gully. Adding to this jumble is that, unwittingly, we may not be talking about the same thing.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

What type of gully is that? The need for a classification of gullies

Thwaites

Brooks

Pietsch

et al. 2021

Earth Surf Processes Landf

View full text Add to dashboard Cite

Despite over a century of investigations into gullies and gully erosion, the characterization and categorization of gullies and the varied definitions, nomenclatures and terminology used has caused some confusion in understanding and communicating the relationships of gully forms and processes around the world. We firstly review the gully literature and highlight how a lack of consistency in gully definition and characterization prevents unifying theory from being developed within this important field of research, since it is often unclear whether different landscape features being discussed are comparable. We propose that conventionally employed qualitative planform and cross‐sectional characteristics of gullies alone are inadequate to define gully types, yet both these features remain central to most modern gully descriptions. We discuss the need to revise and augment these basic characteristics with clearly defined morphogenetic attributes such as landscape context, soil material characteristics, erosion processes, hydrological integrity, modes of development, and head/side‐wall morphology for an effective, practicable, generic gully classification scheme. Central to a gully classification scheme is the need for a clear definition of what a gully is – and is not – for which geomorphological criteria are proposed to differentiate a ‘gully’ from other ‘incisional land surface forms’. This gully definition hinges largely on the identification of a retreating head scarp and the internal erosion by mass‐movement and other sidewall slope erosion processes, coupled with the transport of the soil materials from the gully void. By defining a gully and synthesizing descriptions of gully ‘types’ from the literature and our own experience, we propose key morphogenetic attributes of gullies necessary to form a framework for a systematic gully classification scheme. An initial, eclectic classification framework is presented as both a summation and a synthesis of the literature review, and as a progenitor to a dynamic generic classification scheme that is proposed in a follow‐up article.

show abstract

Cation-anion relationships in crop nutrition: II. Factors affecting the ratios of sum of the cations: sum of the anions in Italian rye-grass

Cunningham

1964

J. Agric. Sci.

View full text Add to dashboard Cite

The first paper of this series (Cunningham, 1964) showed that the sums of the cations (Na + K-jCa + Mg in m-equiv./lOO g.) in Italian rye-grass ranged widely and depended on the sums of the anions (N + P + Cl + S in m-equiv./lOO g.). However, McCalla & Woodford (1938) had previously investigated the relationships between sums of the cations (2 cations) and sums of the anions (2 anions) in wheat and found that the ratios, 2 cations: 2 anions, were constant. Later Bear (1950) claimed that, at any pH when the elements were expressed in m-equiv./lOO g. dry matter, the ratios of sum of the cations: sum of the anions, i.e.

show abstract

Nutritional Balance in Flue-Cured Tobacco

Cited by 4 publications

References 0 publications

Nitrate Uptake by Roots as Regulated by Nitrate Assimilation in the Shoot of Castor Oil Plants

Nitrate Uptake by Roots as Regulated by Nitrate Assimilation in the Shoot of Castor Oil Plants

What type of gully is that? The need for a classification of gullies

Cation-anion relationships in crop nutrition: II. Factors affecting the ratios of sum of the cations: sum of the anions in Italian rye-grass

Contact Info

Product

Resources

About