scholarly journals LEAKAGE OF UV-ABSORBING SOLUTES FROM SALT-AFFECTED ROOT TIPS OF PISTACHIO ROOTSTOCKS

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1136e-1136
Author(s):  
G.A. Picchioni ◽  
S. Miyamoto ◽  
J.B. Storey
Keyword(s):  
Root Growth ◽  
Soil Salinity ◽  
Cellular Damage ◽  
Root Tips ◽  
Pistacia Atlantica ◽  
Solute Leakage ◽  
Soil Solutions ◽  
Saline Solutions ◽  
Made In

Excised root tips from 3-year-old pistachio rootstock (Pistacia atlantica Desf., P. terebinthus L., and P. integerrima Stewart × atlantica) were exposed to laboratory saline solutions for 24 hr. Treatments simulated the compositions of soil solutions in a previous 2-year study made in outdoor lysimeters. Leakage of UV-absorbing solutes, an indication of cellular damage, occurred with 175 mM Na/12.5 mM Ca, which was comparable to soil salinity which increased leaf Na concentrations and decreased root growth of these species Up to. five times higher leakage occurred from roots of a P. terebinthus genotype having least Na exclusion potential during the lysimeter study. Use of isotonic levels of CaCl2, mannitol, and simulated Na/Ca solutions resulted in similar damage. However, isotonic Na (-Ca) caused highest leakage overall. Correlation between long-term observations in the lysimeters and leakage occurrence-in the laboratory indicates that solute leakage tests may aid in characterizing responses of Pistacia spp. roots cocks to saline conditions.

An evaluation of the minirhizotron technique for estimating root distribution in potatoes

1991 ◽  
Vol 116 (3) ◽  
pp. 341-350 ◽  
Author(s):  
C. J. Parker ◽  
M. K. V. Carr ◽  
N. J. Jarvis ◽  
B. O. Puplampu ◽  
V. H. Lee
Keyword(s):  
Root Growth ◽  
Root Length ◽  
Root Length Density ◽  
Quantitative Measure ◽  
Total Root Length ◽  
Root Tips ◽  
Core Sampling ◽  
Glass Tubes ◽  
Poor Soil ◽  
Made In

SUMMARYThe minirhizotron technique was evaluated for estimating root length density in potatoes (Solanum tuberosum‘Record’) by comparing observations in angled 45° glass tubes with corresponding root length densities obtained by (a) destructive core sampling, and from (b) counts of root tips on the soil face of excavated trenches. Measurements were made in a field experiment in Bedfordshire, UK, in 1985, with shallow and deep cultivation as variables, and in a glasshouse trial.Only at depths below 0·3 m did root lengths observed with minirhizotrons reflect at all closely those estimated from core sampling and even then there was a tendency to overestimate root density. In the surface cultivated layers, where 80–90% of the total root length was present, results from minirhizotrons were unreliable, probably because of poor soil–tube contact and, in soils which shrink on drying, preferential root growth at the interface between the soil and the glass.Minirhizotrons can provide a realistic estimate of the rate of root growth of potatoes with depth over time when compared with maximum depths of water extraction, but appear to be unreliable for providing a quantitative measure of total root length density.

A new technique for placement of radioactive solutions in root studies and a study of root growth of Paspalum commersonii

1967 ◽  
Vol 7 (28) ◽  
pp. 447
Author(s):  
TR Evans
Keyword(s):  
Root Growth ◽  
Soil Surface ◽  
New Technique ◽  
Undisturbed Soil ◽  
Test Species ◽  
Repeated Applications ◽  
A New Technique ◽  
Different Diameters ◽  
Made In

A new technique is described for placement of radioactive solutions for studies on root growth. This technique involves placement of a perforated ring of polythene tubing at a predetermined depth with an access tube leading to the soil surface. Cylinders of 16 gauge galvanised iron and of different diameters are used for placement of polythene rings. Soil is excavated from outside the cylinder as it is forced to the required depth ; the polythene is placed in position and soil back-filled over it as the cylinder is withdrawn, thus leaving an undisturbed core of soil of the same diameter as the cylinder to the depth of placement. Radioactive solution introduced through the access tube from an automatic burette is distributed evenly in the soil by percolation from the perforated polythene ring. Rate of root growth of single plants through the undisturbed soil can be determined from measurement of radioactivity in plant leaves at various intervals of time. The technique was tested using radioactive phosphate (32P) as tracer and Paspalm commersonii Lam. as the test species. Root growth both vertically and laterally was measured. The advantages of this technique compared with others at present in use are : 1. Non-disturbance of the soil through which root growth is being measured. 2. Repeated applications of radioactive solution without disturbance of the system may be made in long-term studies. 3. Soil contamination by 32P solution above the point of placement is eliminated. The technique is well suited for studies on root growth and activity of single plants, or for competition studies.

scholarly journals Rapid Testing of Salinity Effects on Pistachio Seedling Rootstock

1991 ◽  
Vol 116 (3) ◽  
pp. 555-559 ◽  
Author(s):  
G.A. Picchioni ◽  
S. Miyamoto ◽  
J.B. Storey
Keyword(s):  
Cell Membrane ◽  
Membrane Permeability ◽  
Cell Injury ◽  
Test Reliability ◽  
Cell Membrane Permeability ◽  
Root Tips ◽  
Laboratory Procedure ◽  
Molar Ratios ◽  
Solute Leakage ◽  
Saline Solutions

A laboratory procedure was used to evaluate saline tolerance of pistachio rootstock species. Results were compared to those from a 2-year, outdoor lysimeter study to test reliability of the method. Excised root tips from seedlings of Pistacia atlantica Desf., P. terebinthus L. (two selections), and P. integerrima Stewart × atlantica (Pioneer Gold II, or PG II), were exposed to laboratory solutions that simulated soil solution electrical conductivity (EC) and Na: Ca ratios in the lysimeters. Following 24 hours of incubation, the efflux of ultraviolet (UV)-absorbing solutes was measured, providing an indication of cell membrane permeability. Leakage occurred with saline solutions comparable to lysimeter soil water salinity that increased leaf Na concentrations and decreased average root growth (175 mm NaCl with 12.5 mm Ca, or EC of 18.1 dS·m-l). Cell injury increased linearly with salinity (R2 = 0.81) and was highest in root tips of a P. terebinthus selection having least Na exclusion capability in the lysimeters. On average, these excised roots lost 38% more solutes than roots of a stronger Na-excluding genotype. There were no differences in leakage responses of the other species and selections. Leakage intensity was independent of various stress media, including isosmotic CaC12, mannitol, and the simulated Na/Ca mixtures in molar ratios of 10:1 to 20:1. With no Ca, however, damage caused by isosmotic NaCl was 76% to 87% higher, indicating that for these species, the Na: Ca ratio can alter root cell membrane permeability. Correlation between long-term observations in the lysimeters and leakage occurrence in the laboratory indicates that solute leakage tests with roots may aid in characterizing Pistacia spp. rootstocks for saline condition.

Soil and ecological division into districts of the Baikal region

2018 ◽  
Vol 940 (10) ◽  
pp. 54-64 ◽  
Author(s):  
I.A. Belozertseva ◽  
A.A. Sorokovoj
Keyword(s):  
Baikal Region ◽  
Soil Cover ◽  
Soil Formation ◽  
Forest Steppe ◽  
Leading Role ◽  
Soil Cover Structure ◽  
Reflecting Surface ◽  
Heat And Moisture ◽  
Made In

On the basis of long-term researches of soils in the territory of Russia and Mongolia soil and ecological division into districts of the Baikal region is carried out. At division into districts the whole set of an environment of soil formation was considered. On the map of soil and ecological division into districts 13 mountain, mid-mountain, low-mountain taiga, foothill, hollow-valley, forest-steppe and steppe provinces reflecting surface device originality as the ratio of balance of heat and moisture forming a basis to zoning is shown against the background of difficult orography are allocated. In total 42 districts on lithologic-geomorphological features are allocated. In formation of distinctions of a soil cover of these provinces the leading role is played by bioclimatic factors and inside them the lithologic-geomorphological ones. In the view of structural approach of the district they are considered as territories with a certain natural change of several types of the soil cover structure caused by features of a relief and the parent rock. The map is made in the MapInfo program. It is revealed that on ill-defined width zoning of soils the vertical one which has a greater influence on soils of this region is imposed. Soils of the Baikal region are not similar to the soils located at the same latitude of the flat European territory of Russia. Zone soils of this territory are specific and original.

scholarly journals Mechanical Properties of Cement-Treated Soil Mixed with Cellulose Nanofibre

2021 ◽  
Vol 11 (14) ◽  
pp. 6425
Author(s):  
Hidenori Takahashi ◽  
Shinya Omori ◽  
Hideyuki Asada ◽  
Hirofumi Fukawa ◽  
Yusuke Gotoh ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Geotechnical Engineering ◽  
Strength Development ◽  
Soft Ground ◽  
Wood Cellulose ◽  
Treated Soil ◽  
Made In ◽  
Cement Treatment

Cellulose nanofibre (CNF), a material composed of ultrafine fibres of wood cellulose fibrillated to nano-order level, is expected to be widely used because of its excellent properties. However, in the field of geotechnical engineering, almost no progress has been made in the development of techniques for using CNFs. The authors have focused on the use of CNF as an additive in cement treatment for soft ground, where cement is added to solidify the ground, because CNF can reduce the problems associated with cement-treated soil. This paper presents the results of a study on the method of mixing CNF, the strength and its variation obtained by adding CNF, and the change in permeability. CNF had the effect of mixing the cement evenly and reducing the variation in the strength of the treated soil. The CNF mixture increased the strength at the initial age but reduced the strength development in the long term. The addition of CNF also increased the flexural strength, although it hardly changed the permeability.

Long-term liming improves soil fertility and soybean root growth, reflecting improvements in leaf gas exchange and grain yield

2021 ◽  
Vol 128 ◽  
pp. 126308
Author(s):  
João William Bossolani ◽  
Carlos Alexandre Costa Crusciol ◽  
José Roberto Portugal ◽  
Luiz Gustavo Moretti ◽  
Ariani Garcia ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Root Growth ◽  
Soil Fertility ◽  
Grain Yield ◽  
Leaf Gas Exchange ◽  
Soybean Root

scholarly journals Linking Long-Term Changes in Soil Salinity to Paddy Land Abandonment in Jaffna Peninsula, Sri Lanka

Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 211
Author(s):  
Tharani Gopalakrishnan ◽  
Lalit Kumar
Keyword(s):  
Sri Lanka ◽  
Soil Salinity ◽  
Agricultural Land ◽  
Sea Water ◽  
Land Use Changes ◽  
Soil Salinization ◽  
Landsat Images ◽  
Paddy Land ◽  
Semi Arid Region

Soil salinity is a serious threat to coastal agriculture and has resulted in a significant reduction in agricultural output in many regions. Jaffna Peninsula, a semi-arid region located in the northern-most part of Sri Lanka, is also a victim of the adverse effects of coastal salinity. This study investigated long-term soil salinity changes and their link with agricultural land use changes, especially paddy land. Two Landsat images from 1988 and 2019 were used to map soil salinity distribution and changes. Another set of images was analyzed at four temporal periods to map abandoned paddy lands. A comparison of changes in soil salinity with abandoned paddy lands showed that abandoned paddy lands had significantly higher salinity than active paddy lands, confirming that increasing salts owing to the high levels of sea water intrusion in the soils, as well as higher water salinity in wells used for irrigation, could be the major drivers of degradation of paddy lands. The results also showed that there was a dramatic increase in soil salinity (1.4-fold) in the coastal lowlands of Jaffna Peninsula. 64.6% of the salinity-affected land was identified as being in the extreme saline category. In addition to reducing net arable lands, soil salinization has serious implications for food security and the livelihoods of farmers, potentially impacting the regional and national economy.

No Justice Without Peace, But What Peace Is on Offer?

2020 ◽  
Author(s):  
Mark Kersten
Keyword(s):  
Middle East ◽  
International Criminal Court ◽  
International Criminal ◽  
Criminal Court ◽  
Term Stability ◽  
Long Term Stability ◽  
Peace Processes ◽  
Lasting Peace ◽  
Made In

Abstract Does the potential investigation into Palestine by the International Criminal Court (ICC) threaten the chances of a lasting ‘peace’ between Israel and Palestine? This article endeavours to answer that question and critically assesses claims that the Court could undermine peace in the Middle East. I first examine the key claims made in the so-called ‘peace versus justice’ debate. I then outline some of the specific arguments made in the context of a possible ICC investigation in Palestine that touch upon concerns over the Court’s impacts on peace processes and negotiations. Following this, I try to assess critically the validity of these claims, arguing that while it would be wrong to conclude that the ICC will invariably have positive impacts on efforts to establish peace, there is no evidence that the Court will undermine whatever ‘peace’ is currently on offer for Palestinians and Israelis. On the contrary, this ‘peace’ may itself be a threat to resolving the conflict peaceably and to long-term stability in the region. Finally, I conclude the article with some reflections on the peace-justice debate and its applicability to the Israel–Palestine situation.

Species Responses to Grazing and Environmental-Factors in an Arid Halophytic Shrubland Community

1987 ◽  
Vol 35 (2) ◽  
pp. 135 ◽  
Author(s):  
RB Hacker
Keyword(s):  
Environmental Factors ◽  
Soil Salinity ◽  
Large Scale ◽  
Chemical Properties ◽  
Grazing Pressure ◽  
Aerial Photographs ◽  
Small Scale ◽  
Factors Affecting ◽  
Species Responses

Species responses to grazing and environmental factors were studied in an arid halophytic shrubland community in Western Australia. The grazing responses of major shrub species were defined by using reciprocal averaging ordination of botanical data, interpreted in conjunction with a similar ordination of soil chemical properties and measures of soil erosion derived from large-scale aerial photographs. An apparent small-scale interaction between grazing and soil salinity was also defined. Long-term grazing pressure is apparently reduced on localised areas of high salinity. Environmental factors affecting species distribution are complex and appear to include soil salinity, soil cationic balance, geomorphological variation and the influence of cryptogamic crusts on seedling establishment.

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