Root depth of native and sown perennial grass-based pastures, North-West Slopes, New South Wales. 1. Estimates from cores and effects of grazing treatments

2006 ◽  
Vol 46 (3) ◽  
pp. 337 ◽  
Author(s):  
G. M. Lodge ◽  
S. R. Murphy

Studies were undertaken on native and sown perennial grass-based pastures as part of the Sustainable Grazing Systems National Experiment to estimate root depth and describe root distribution in these pastures. Samples from soil cores (0–210 cm maximum sampling depth) taken in 1997 (before grazing treatments were imposed) and 4 years later in spring 2001 were used to examine the effects of different grazing regimes on root length density (cm/cm3), root mass density (mg/cm3), root volume density (cm3/cm3), and diameter (mm) at each of 3 sites. In spring 1997, mean maximum root depth was 107 cm for a native perennial grass pasture near Barraba and 74 cm for a pasture sown with phalaris (Phalaris aquatica) and subterranean clover (Trifolium subterraneum) near Nundle, with values being lower for a native pasture near Manilla (65 cm for a Brown Vertosol and 97 cm for a Red Chromosol). For all pasture types, >20% of root mass density, root length density or root volume density was in the 0–5 cm soil layer and >60% was at a depth of 0–30 cm. At all sites, mean total root mass was around 1000 kg DM/ha. After 4 years of grazing (spring 2001) there were relatively few significant effects of grazing treatment on root length density, root mass density, root volume density, or root diameter. Effects that were significant mostly occurred at 0–5 cm for the native pastures and 0–50 cm for the sown pasture. For the Barraba native pasture, root length, volume and mass densities (0–5 cm) were higher (P<0.05) in the continuously grazed, low stocking rate treatment compared with all other treatments. Similarly, for the Manilla native pasture, root length density was higher (P<0.05) in this treatment at soil depths of 0–5 and >5–10 cm compared with all other treatments. In contrast, for the Nundle sown pasture, root length density (0–5 cm) was lowest (P<0.05) in 2 continuously grazed treatments compared with those that were strategically grazed in autumn and spring.

2021 ◽  
Vol 23 (3) ◽  
pp. 257-264
Author(s):  
SHRUTHI REDDY L ◽  
GOPALA KRISHNA REDDY A ◽  
VANAJA. M ◽  
MARUTHI. V. ◽  
VANAJA LATHA. K.

An experiment was laid out to study the impact of eCO2 (550ppm), eT (+3ºC) and their interaction (eCO2+eT) on rooting behaviour of cuttings of three grape varieties- Thompson Seedless, Bangalore Blue, and Dogridge in FATE and OTC facilities. Observations were recorded at 50 and 80 days after planting (DAP) and root growth data was recorded and analysed using WinRHIZO root scanner and its software. Analysis revealed that, among the selected grape varieties, Thompson Seedless cuttings has shown highest number of roots, root volume and dry biomass under eCO2 and eCO2+ eT conditions, while total root length and root length density were highest with Bangalore Blue. Under eT condition, Bangalore Blue showed highest number of roots, total root length and root length density, while root volume and dry biomass was highest with Thompson Seedless. The per se values of root parameters under all conditions and their response to eCO2 was lowest with Dogridge. Though eT condition reduced all the root parameters, their performance improved under eCO2+ eT indicating the presence of higher concentration of CO2 reduced the ill effects of high temperature. Overall, eCO2 and eCO2+eT conditions improved root parameters of grape varieties, while eT reduced them as compared to their performance under ambient condition and varietal variation is significant.


Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1355
Author(s):  
Pavel Svoboda ◽  
Gabriela Kurešová ◽  
Ivana Raimanová ◽  
Eva Kunzová ◽  
Jan Haberle

The purpose of this study was to determine the effect of sixty years of contrasting fertilization treatments on the roots of winter wheat (Triticum aestivum L.) at sites with different soil and climate conditions. The depth and length density distribution of the wheat roots were determined between 2014 and 2016 in a crop rotation experiment established in 1955 at three sites: Lukavec, Čáslav, and Ivanovice (Czech Republic). Three fertilization treatments were examined: Zero fertilization (N0), organic (ORG) fertilization, and mineral (MIN) fertilization. The fertilization, site, and year all had a significant effect on the total root length (TRL). The average TRL per square meter reached 30.2, 37.0, and 46.1 km with the N0, ORG, and MIN treatments at Lukavec, respectively, which was the site with the lightest soil and the coldest climate. At Čáslav and Ivanovice (warmer sites with silt and loamy soils), the average TRL per square meter reached 41.2, 42.4, and 47.7 km at Čáslav and 49.2, 55.3, and 62.9 km at Ivanovice with the N0, MIN, and ORG treatments, respectively. The effect of fertilization on the effective root depth (EfRD), the depth at which the root length density dropped below 2.0 cm cm−3, was significant, while the maximum root depth (RMD) was only marginally affected. With the sites and years averaged, the MIN-treated plants showed a greater EfRD (102.2 cm) in comparison to the N0 (81.8 cm) and ORG (93.5 cm) treatments. The N0 treatment showed no signs of an adaptive reaction to the root system, with potential improvement for nutrient acquisition, while optimal fertilization contributed to the potential for resource depletion from the soil profile.


2019 ◽  
Vol 31 (2) ◽  
pp. 285-299 ◽  
Author(s):  
Ioanna P. Kakabouki ◽  
Ioannis Roussis ◽  
Dimitra Hela ◽  
Panayiota Papastylianou ◽  
Antigolena Folina ◽  
...  

AbstractQuinoa is a gluten-free pseudocereal crop recognized for its exceptional nutritional properties. A 3-year field experiment was conducted to evaluate the influence of soil tillage and fertilization on root growth and productivity of quinoa. The experiment was laid out in a split-plot design with two replicates, two main plots [conventional (CT) and minimum tillage (MT)] and four sub-plots [fertilization treatments: untreated, inorganic fertilization with 100 (N1) and 200 kg N ha−1 (N2), and sheep manure]. Mean weight diameter (MWD) of soil aggregates, total porosity, organic matter and soil total nitrogen increased with the long-term fertilization with sheep manure. The major part of the roots (approximately 70%) is concentrated in the 0-30 cm soil layer. Root length density increased with increased rate of applied nitrogen, and a higher value (1.172 cm cm−3) was found in N2 plots. Additionally, higher root mass density (1.114 mg cm−3) was observed under MT. Plant height and dry weight were clearly affected by fertilization, with higher values obtained in N2 plots. Moreover, it was observed that quinoa cultivated under CT and N2 treatment produced a higher seed yield (2595 kg ha−1). As a conclusion, increasing the levels of applied nitrogen up to 200 kg N ha−1 improves root growth and consequently the yields of quinoa.


2021 ◽  
Vol 237 ◽  
pp. 01042
Author(s):  
Qiuhua Li ◽  
Jingjing Sun ◽  
Jun Yao ◽  
Qunhui Wang

A maize field experiment in the North China Plain was conducted to understand the effect of different N fertilizer rate on the yield of maize, using soil microbial activity and root length density (RLD) as performance parameters, due to their possibility to enhance productivity. The four N fertilizer rates were 0 (N0), 120 (N120), 210 (N210) and 300 (N300) kg N hm-2. The results indicated that nitrogen (N) fertilizer had a significant influence not only on yield (p<0.05), but also on root length density (p<0.05) and soil microbial activity (p<0.05). In addition, the soil microbial activity and RLD were significantly related with maize yield. RLD differences were generally evident within the 100 cm soil layer, whereas there was no difference in the deeper soil under different N treatments. The most RLD concentrated in 0-60cm soil layer under N0, N120 and in 0-90cm soil layer under N210, N300. The microbial growth rate constant (k) was greater in N210 than other treatments. Generally, N fertilizer application can stimulate root growth and microbial activity, meanwhile, they can interact with each other, heighten the availability of N fertilizer in soil, thus enhanced yield of maize. According to our study, 210 kg N hm-2 was the optimum N fertilizer rate to achieve maximum yield and sustain the soil productivity.


1992 ◽  
Vol 43 (1) ◽  
pp. 19 ◽  
Author(s):  
KY Chan ◽  
JA Mead

Root growth and distribution of wheat under different tillage practices was studied in a 4-year-old tillage experimental site at Cowra, N.S.W. Tillage affected root density as well as distribution. Up to 98 days after sowing, root length density was lower (P < 0.05) in the 0.05-0.10 m layer of the direct-drilled soil than the conventionally cultivated soil. Poor root growth found in direct-drilled soils, which was significantly related to the poor shoot growth, was not caused by soil physical conditions, viz. higher bulk density and soil strength. Rather, biological factors were involved because fumigation completely eliminated the poor shoot growth and significantly increased root length density of the direct drilled soils. Compared to a compaction treatment, roots grown under direct drilling, in addition to having lower density, also had impaired function. Under conventional cultivation, significantly lower root length density was found in the surface soil layer (0-0.05 m) and maximum root length density was found in the 0-05-0.10 m layer. Fumigation did not change the root distribution pattern. This tillage-induced difference in root distribution reflected less favourable surface soil conditions as a result of cultivation, e.g. seedbed slumping, compared to the soil under direct drilling.


Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1394
Author(s):  
Larícia Olária Emerick Silva ◽  
Raquel Schmidt ◽  
Gustavo Pereira Valani ◽  
Adésio Ferreira ◽  
Ana I. Ribeiro-Barros ◽  
...  

Coffee breeding based on root traits is important to identify productive genotypes under adverse environmental conditions. This study assessed the diversity of root traits in Coffea canephora and its correlation with plant height and crop yield. Undisturbed soil samples were collected down to 60 cm from 43 coffee genotypes, in which one of them was propagated by seed and all others by stem cutting. The roots were washed, scanned, and processed to quantify root length density, root volume, root superficial area, and root diameter. Additionally, plant height and crop yield were also assessed. Root length density ranged from 40 to 1411 mm cm−3, root volume from 6 to 443 mm3 cm−3, root superficial area from 61 to 1880 mm2 cm−3, and root diameter from 0.6 to 1.1 mm. Roots were concentrated in the topsoil (0–20 cm) for most genotypes. In deeper depths (30–60 cm), root length density, root volume, and root superficial area were higher in genotypes 14, 25, 31, and 32. Positive correlations were found between root traits and both plant height and crop yield. The results of this work may contribute to the overall cultivation of C. canephora, specially for crop breeding in adverse environmental conditions.


2006 ◽  
Vol 57 (10) ◽  
pp. 1097 ◽  
Author(s):  
Mingtan Liao ◽  
Jairo A. Palta ◽  
Ian R. P. Fillery

Root growth is important for the acquisition of nitrogen (N) and water in deep sandy soil profiles with high leaching potential. Root growth characteristics and the N uptake of wheat genotypes differing in early vigour were investigated in 2 glasshouse experiments. In both experiments the vigorous breeding lines Vigor18 and B18 and the well-adapted commercial cultivar Janz were grown in glass-walled growth boxes in a controlled-temperature glasshouse up to the onset of stem elongation. In Expt 1, rooting parameters and detailed measurements of root growth and proliferation were made at 2-day intervals using a root mapping technique. In Expt 2 the glass-walled growth boxes were segmented into upper (0–0.2 m), middle (0.2–0.7 m), and bottom (0.7–1.0 m) soil layers, and the contribution of N fertiliser uptake by roots from each soil layer to the total plant N uptake was determined by applying 15N-urea to a single soil layer each time. The accumulated total root length across the soil profile from the 1-leaf stage to the onset of stem elongation was 33–83% higher in the vigorous lines Vigor18 and B18 than in Janz. The roots of the 3 genotypes grew vertically down the soil profile at a similar rate, but the roots of vigorous lines branched earlier and grew horizontally faster and more extensively than those of cv. Janz, resulting in a greater root-length density and root number in the top 0.7-m soil layer. Uptake of N fertiliser by roots in the upper 0–0.2 m of the soil profile was 60–68% higher in the vigorous lines than in Janz. Roots of the vigorous lines located in the segment 0.2–0.7 m of the soil profile captured twice as much N fertiliser than those of Janz. Uptake of N fertiliser by roots in the lower 0.7–1.0 m of the soil profile was similar in the vigorous lines and Janz. This indicates that the early and more extensive horizontal growth of the roots in the 0.2–0.7 m of the soil profile was responsible for the superior uptake of N by the vigorous lines. The implications of these genotypic differences in root growth and proliferation and their relationship with the early acquisition of N are discussed with emphasis on their role in improving the efficiency of N fertiliser uptake and reducing nitrate leaching, particularly in the sandy soils of the Mediterranean climatic region of Australia.


2015 ◽  
Vol 66 (4) ◽  
pp. 249 ◽  
Author(s):  
J. A. Kirkegaard ◽  
J. M. Lilley ◽  
J. R. Hunt ◽  
S. J. Sprague ◽  
N. K. Ytting ◽  
...  

Dual-purpose crops for grazing and grain production can be highly profitable, provided grazing does not cause significant loss of grain yield. In many plants, defoliation causes a transient reduction in the allocation of resources to stem and root growth and remobilisation of soluble resources to re-establish leaf area rapidly. In Australia, the usual autumn and winter period of defoliation for grazed crops, May–July, coincides with a phase of near-linear root depth penetration in ungrazed crops, and the crop recovery period after grazing occurs during stem elongation, when grain number and yield potential are determined. However, few studies have investigated the potential impact of crop defoliation through grazing on root growth of wheat in the field. We investigated the effect of defoliation by grazing or shoot removal on the root growth of wheat crops in four field experiments in south-eastern Australia in which the timing, frequency and intensity of defoliation varied. Despite significant impacts of defoliation on aboveground biomass (50–90% reduction) and grain yield (10–43% reduction) in all experiments, we found little evidence of effects on the rate of root penetration or final rooting depth. A notable exception was observed in one experiment when defoliation commenced very early (four-leaf stage, Zadoks growth stage Z14) in a repeatedly defoliated crop, reducing rooting depth from 1.65 to 1.35 m. The only other measured impact on roots was in an early-sown winter wheat crop grazed by sheep for 3 months (6 June–3 September), in which root length density was reduced by ~50% in surface layers above 1.0 m depth, but there was no impact on maximum root depth or root length density at 1.0–2.0 m depth. Our results suggest that grazing has little impact on the rooting depth of wheat unless it occurs very early and repeatedly, when plants are allocating significant resources to establish the primary roots. However, there may be some reduction in the density of roots in surface layers during recovery after long-term grazing, presumably associated with reduced proliferation of the nodal root system. We conclude that most significant yield penalties due to grazing relate to impacts on the assimilation of aboveground resources, rather than to reduced water or nutrient acquisition by roots.


2011 ◽  
Vol 35 (5) ◽  
pp. 956-964 ◽  
Author(s):  
José Donizeti Alves ◽  
Carlos Maurício Paglis ◽  
Darlan Einstein do Livramento ◽  
Suellen Sarah Drumond Linhares ◽  
Frederico Biagi Becker ◽  
...  

This paper investigated changes in growth and carbohydrate content of shoots and root systems in response to source-sink manipulation in field-grown coffee trees. The source-sink manipulations were carried out using manual de-fruiting. Two plots of trees were established: in one group, the fruit was left on the tree, while in the second group all fruits were removed manually. Similar results were obtained for coffee trees with and without fruit in terms of height, stem and skirt diameter and branch lengths. A biochemical evaluation of the roots showed that no differences were found between the levels of carbohydrates. In the leaves, levels of soluble sugars and reducing sugars were higher in plants with fruit. The starch concentration in leaves and roots did not vary between the plots. Root length density did not vary between plants with and without fruit in the 0 - 0.4 m soil layer. However, plants without fruit had a higher root length density than plants with a full fruit load. These results contrast with results published by others on source-sink relationships of coffee plants. The joint data analysis shows that young trees, with a moderate fruit load, and with good nutritional and health status, produce carbohydrates in sufficient quantities to maintain vegetative and reproductive growth, without harming root system growth.


1998 ◽  
Vol 63 ◽  
Author(s):  
L. Vande Walle ◽  
S. Willems ◽  
R. Lemeur

Root  length and root mass were studied in two different forest stands: an  oak-beech and an ash stand, both in the 'Aelmoeseneie' experimental forest at Gontrode, Belgium. In the oak-beech    stand, the length of the finest roots &lt; 1 mm) was significantly higher  than the length of the other    diameter classes (1-2 and 2-5 mm) in the upper 60 cm of the mineral soil.  Because of large    variances, this significance could not be found in the ash forest. In this  ash forest type, the length    of the finest roots in the upper mineral soil layer (0-15 cm) was higher  than all the other lengths,    both considering the vertical root length distribution within the ash plot,  and comparing the ash plot    to the oak-beech stand. For the root mass, only the amount of roots with a  diameter between 2    and 5 mm in the upper mineral soil layer of the ash plot was significantly  higher than the others.    SpecifiC root length (m root/g D.M.) is calculated for both the oak-beech  and the ash plot. These    values can be used to convert biomass data into root length data, which  gives a better indication of    the water uptake capacity of the forest stand.


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