scholarly journals Two Wheat Cultivars with Contrasting Post-Embryonic Root Biomass Differ in Shoot Re-Growth after Defoliation: Implications for Breeding Grazing Resilient Forages

Plants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 470
Author(s):  
Paez-Garcia ◽  
Liao ◽  
Blancaflor
Keyword(s):  
Winter Wheat ◽  
Root Growth ◽  
Root System ◽  
Aboveground Biomass ◽  
Root Traits ◽  
Shoot Biomass ◽  
Wheat Cultivars ◽  
Leaf Clipping ◽  
The Impact ◽  
Embryonic Root

The ability of forages to quickly resume aboveground growth after grazing is a trait that enables farmers to better manage their livestock for maximum profitability. Leaf removal impairs root growth. As a consequence of a deficient root system, shoot re-growth is inhibited leading to poor pasture performance. Despite the importance of roots for forage productivity, they have not been considered as breeding targets for improving grazing resilience due in large part to the lack of knowledge on the relationship between roots and aboveground biomass re-growth. Winter wheat (Triticum aestivum) is extensively used as forage source in temperate climates worldwide. Here, we investigated the impact of leaf clipping on specific root traits, and how these influence shoot re-growth in two winter wheat cultivars (i.e., Duster and Cheyenne) with contrasting root and shoot biomass. We found that root growth angle and post-embryonic root growth in both cultivars are strongly influenced by defoliation. We discovered that Duster, which had less post-embryonic roots before defoliation, reestablished its root system faster after leaf cutting compared with Cheyenne, which had a more extensive pre-defoliation post-embryonic root system. Rapid resumption of root growth in Duster after leaf clipping was associated with faster aboveground biomass re-growth even after shoot overcutting. Taken together, our results suggest that lower investments in the production of post-embryonic roots presents an important ideotype to consider when breeding for shoot re-growth vigor in dual purpose wheat.

scholarly journals Effect of Fluoride on Germination, Early Growth and Antioxidant Enzymes Activity of Three Winter Wheat (Triticum aestivum L.) Cultivars

2020 ◽  
Vol 10 (19) ◽  
pp. 6971
Author(s):  
Justyna Pelc ◽  
Martyna Śnioszek ◽  
Jacek Wróbel ◽  
Arkadiusz Telesiński
Keyword(s):  
Antioxidant Enzymes ◽  
Winter Wheat ◽  
Root Growth ◽  
Wheat Cultivar ◽  
Fluoride Concentration ◽  
Triticum Aestivum L ◽  
Wheat Cultivars ◽  
Growth Phases ◽  
Winter Wheat Cultivars ◽  
The Impact

This paper assesses the impact of sodium fluoride on the morphological parameters and activity of catalase and peroxidase during the germination and root growth phases of three winter wheat cultivars: Tobak, Dalewar, and Arkadia. During examination, the seeds were placed on plastic Petri dishes with an NaF solution at concentrations of 0 (control), 2.5, 5.0, 8.0, and 10.0 mmol dm−3. The obtained results have shown a decrease in germination, inhibition of root growth, and inhibition of catalase activity, both in the embryos and roots of all tested winter wheat cultivars. The observed effects have been strengthened with the increase of the fluoride concentration. However, the effect of NaF on the peroxidase activity has been dependent on the wheat cultivar. It is difficult to state unequivocally which of the tested winter wheat cultivars has been characterized by the highest sensitivity to fluoride. An η2 analysis has confirmed that the NaF concentration has a greater effect than the winter wheat cultivar on the activity of the determined antioxidant enzymes.

scholarly journals Early Season Drought Largely Reduces Grain Yield in Wheat Cultivars with Smaller Root Systems

Plants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 305 ◽  
Author(s):  
Victoria Figueroa-Bustos ◽  
Jairo A. Palta ◽  
Yinglong Chen ◽  
Kadambot H.M. Siddique
Keyword(s):  
Grain Yield ◽  
Root System ◽  
Leaf Area ◽  
Root Traits ◽  
Root Systems ◽  
Shoot Biomass ◽  
Wheat Cultivars ◽  
Early Season ◽  
Leaf Photosynthetic Rate ◽  
Better Than

In the Australian grainbelt, early winter rainfall has declined during the last 30 years, and farmers sow their crops dry, increasing the risk of early season drought. This study aimed to examine whether differences in the root systems were associated with tolerance to early season drought. Three wheat cultivars with different root systems were grown in 1 m columns in a glasshouse. Immediately after sowing in dry soil, 440 mL water (equivalent to 25 mm rainfall) was supplied to each column, and no water was added to induce the early-season drought for the next 30 days. Shoot and root traits were measured at the end of the early season drought, anthesis and at maturity, respectively. The restricted water supply reduced Ψleaf, stomatal conductance, leaf photosynthetic rate, shoot and root biomass. Early season drought delayed phenology in all cultivars, but there was recovery of root and shoot biomass at anthesis in all three cultivars. Leaf area and shoot biomass at anthesis in Bahatans-87 (large root system) recovered better than Tincurrin (small root system). At maturity, early season drought reduced grain yield more in Tincurrin than Bahatans-87. The slow phenology of Bahatans-87 allowed greater recovery after the drought in leaf area and shoot biomass, which may explain the smaller reduction in grain yield after early season drought.

Estimating Yield Losses Due to Barley Yellow Dwarf on Winter Wheat in Kansas Using Disease Phenotypic Data

2015 ◽  
Vol 16 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Genna M. Gaunce ◽  
William W. Bockus
Keyword(s):  
Winter Wheat ◽  
Yield Loss ◽  
Disease Incidence ◽  
Relative Yield ◽  
Yellow Dwarf ◽  
Wheat Cultivars ◽  
Grain Yields ◽  
Barley Yellow Dwarf ◽  
Winter Wheat Cultivars ◽  
The Impact

Barley yellow dwarf (BYD) is one of the most important wheat diseases in the state of Kansas. Despite the development of cultivars with improved resistance to BYD, little is known about the impact that this resistance has on yield loss from the disease. The intent of this research was to estimate yield loss in winter wheat cultivars in Kansas due to BYD and quantify the reduction in losses associated with resistant cultivars. During seven years, BYD incidence was visually assessed on numerous winter wheat cultivars in replicated field nurseries. When grain yields were regressed against BYD incidence scores, negative linear relationships significantly fit the data for each year and for the combined dataset covering all seven years. The models showed that, depending upon the year, 19–48% (average 33%) of the relative yields was explained by BYD incidence. For the combined dataset, 29% of the relative yield was explained by BYD incidence. The models indicated that cultivars showing the highest disease incidence that year had 25–86% (average 49%) lower yield than a hypothetical cultivar that showed zero incidence. Using the models, the moderate level of resistance in the cultivar Everest was calculated to reduce yield loss from BYD by about 73%. Therefore, utilizing visual BYD symptom evaluations in Kansas coupled with grain yields is useful to estimate yield loss from the disease. Accepted for publication 1 December 2014. Published 9 January 2015.

Insights into the functional relationship between cytokinin-induced root system phenotypes and nitrate uptake in Brassica napus

2017 ◽  
Vol 44 (8) ◽  
pp. 832 ◽  
Author(s):  
Qianqian Guo ◽  
Jonathan Love ◽  
Jiancheng Song ◽  
Jessica Roche ◽  
Matthew H. Turnbull ◽  
...  
Keyword(s):  
Brassica Napus ◽  
Root System ◽  
Culture Media ◽  
Root Traits ◽  
Spatial Arrangement ◽  
Shoot Biomass ◽  
N Availability ◽  
Root Proliferation ◽  
Brassica Napus L ◽  
15N Uptake

Root system architecture is the spatial arrangement of roots that impacts the capacity of plants to access nutrients and water. We employed pharmacologically generated morphological and molecular phenotypes and used in situ 15N isotope labelling, to investigate whether contrasting root traits are of functional interest in relation to nitrate acquisition. Brassica napus L. were grown in solidified phytogel culture media containing 1 mM KNO3 and treated with the cytokinin, 6-benzylaminopurine, the cytokinin antagonist, PI-55, or both in combination. The pharmacological treatments inhibited root elongation relative to the control. The contrasting root traits induced by PI-55 and 6-benzylaminopurine were strongly related to 15N uptake rate. Large root proliferation led to greater 15N cumulative uptake rather than greater 15N uptake efficiency per unit root length, due to a systemic response in the plant. This relationship was associated with changes in C and N resource distribution between the shoot and root, and in expression of BnNRT2.1, a nitrate transporter. The root : shoot biomass ratio was positively correlated with 15N cumulative uptake, suggesting the functional utility of root investment for nutrient acquisition. These results demonstrate that root proliferation in response to external nitrate is a behaviour which integrates local N availability and the systemic N status of the plant.

scholarly journals Intra and inter-annual climatic conditions have stronger effect than grazing intensity on root growth of permanent grasslands

2020 ◽  
Author(s):  
Catherine Picon-Cochard ◽  
Nathalie Vassal ◽  
Raphaël Martin ◽  
Damien Herfurth ◽  
Priscilla Note ◽  
...  
Keyword(s):  
Root Growth ◽  
Grazing Intensity ◽  
Root Traits ◽  
C Sequestration ◽  
Grazing Pressure ◽  
Climatic Conditions ◽  
Root Production ◽  
Shoot Biomass ◽  
Ingrowth Cores ◽  
Growing Seasons

AbstractBackground and AimsUnderstanding how direct and indirect changes in climatic conditions, management, and species composition affect root production and root traits is of prime importance for grassland C sequestration service delivery.MethodsWe studied during two years the dynamics of root mass production with ingrowth-cores and annual above- and below-ground biomass (ANPP, BNPP) of upland fertile grasslands subjected for 10 years to a gradient of herbage utilization by grazing.ResultsWe observed strong seasonal root production across treatments in both a wet and a dry year but response to grazing intensity was hardly observed within growing seasons. In abandonment, spring and autumn peaks of root growth were delayed by about one month compared to cattle treatments, possibly due to later canopy green-up and lower soil temperature. BNPP was slightly lower in abandonment compared to cattle treatments only during the dry year, whereas this effect on ANPP was observed the wet year. In response to drought, the root-to-shoot biomass ratio declined in the abandonment but not in the cattle treatment, underlining higher resistance to drought of grazed grassland communities.ConclusionsRotational grazing pressure and climatic conditions variability had very limited effects on root growth seasonality although drought had stronger effects on BNPP than on ANPP.

Water relations of winter wheat: 1. Growth of the root system

1978 ◽  
Vol 91 (1) ◽  
pp. 91-102 ◽  
Author(s):  
P. J. Gregory ◽  
M. McGowan ◽  
P. V. Biscoe ◽  
B. Hunter
Keyword(s):  
Winter Wheat ◽  
Root Growth ◽  
Root System ◽  
Water Relations ◽  
Root Length ◽  
Dry Weight ◽  
Growing Season ◽  
Main Stem ◽  
Soil Cores ◽  
Root Dry Weight

SummaryThe production of root axes and the growth of the root system are reported for a commercially grown crop of Maris Huntsman winter wheat. Soil cores were extracted on 17 occasions during the growing season permitting a detailed study of root length and root dry weight with depth and time.Production of seminal root axes was complete by the beginning of March when all plants possessed six (occasionally seven) axes which persisted throughout the life of the crop. Nodal axes were produced continuously from mid-February until late May and finally numbered approximately 20 stem nodal axes per main stem. Total root dry weight increased exponentially until the beginning of April and then almost linearly to reach a maximum of 105 g root/m2 field in mid-June (anthesis). After anthesis, total root dry weight decreased but root growth continued below 80 cm. From April onwards, approximately 65% of the total root dry weight was in the 0–30 cm layer.

scholarly journals Shovelomics root traits assessed on the EURoot maize panel are highly heritable across environments but show low genotype-by-nitrogen interaction

Euphytica ◽  
2019 ◽  
Vol 215 (10) ◽  
Author(s):  
Chantal A. Le Marié ◽  
Larry M. York ◽  
Alexandre Strigens ◽  
Marcos Malosetti ◽  
Karl-Heinz Camp ◽  
...  
Keyword(s):  
Root System ◽  
Root Traits ◽  
N Fertilization ◽  
N Availability ◽  
Stay Green ◽  
N Application ◽  
Growth Environment ◽  
Root Stock ◽  
Horizontal Expansion ◽  
The Impact

Abstract The need for sustainable intensification of agriculture in the coming decades requires a reduction in nitrogen (N) fertilization. One opportunity to reduce N application rates without major losses in yield is breeding for nutrient efficient crops. A key parameter that influences nutrient uptake efficiency is the root system architecture (RSA). To explore the impact of N availability on RSA and to investigate the impact of the growth environment, a diverse set of 36 inbred dent maize lines crossed to the inbred flint line UH007 as a tester was evaluated for N-response over 2 years on three different sites. RSA was investigated by excavating and imaging of the root crowns followed by image analysis with REST software. Despite strong site and year effects, trait heritability was generally high. Root traits showing the greatest heritability (> 0.7) were the width of the root stock, indicative of the horizontal expansion, and the fill factor, a measure of the density of the root system. Heritabilities were in a similar range under high or low N application. Under N deficiency the root stock size decreased, the horizontal expansion decreased and the root stock became less dense. However, there was little differential response of the genotypes to low N availability. Thus, the assessed root traits were more constitutively expressed rather than showing genotype-specific plasticity to low N. In contrast, strong differences were observed for ‘stay green’ and silage yield, indicating that these highly heritable traits are good indicators for responsiveness to low N.

scholarly journals Transcriptomic Analysis Reveals the Contribution of QMrl-7B to Wheat Root Growth and Development

2020 ◽  
Author(s):  
Jiajia Liu ◽  
Hanwen Li ◽  
Na Zhang ◽  
Deyuan Meng ◽  
Liya Zhi ◽  
...  
Keyword(s):  
Root Growth ◽  
Root System ◽  
Root Traits ◽  
Wheat Root ◽  
Root System Architecture ◽  
Transcriptomic Analysis ◽  
Differentially Expressed ◽  
Yield Potential ◽  
Trait Locus ◽  
Normal Nitrogen

Abstract Backgound: Roots are the major organs for water and nutrient acquisition and substantially affect plant growth, development and reproduction. Improvements to root system architecture are highly important for increasing yield potential of bread wheat. QMrl-7B, a major stable quantitative trait locus (QTL) that controls maximum root length (MRL), strongly contributes to an improved root system in wheat. Results: To further analyse the biological functions of QMrl-7B in root development, two types of Triticum aestivum near isogenic lines (NILs), one with superior QMrl-7B alleles from cultivar Kenong 9204 (KN9204) and another with inferior QMrl-7B alleles from cultivar Jing 411 (J411), were subjected to transcriptomic analysis. Among all the mapped genes analysed, 4871 genes were identified as being differentially expressed between the pairwise NILs under different nitrogen (N) conditions, with 3543 genes expressed under normal-nitrogen (NN) condition and 2689 genes expressed under low-nitrogen (LN) condition. These genes encode proteins that include mainly NO3- transporters, phytohormone signalling components and transcription factors (TFs), indicating the presence of a complex regulatory network involved in root determination. In addition, among the 13524 LN-induced differentially expressed genes (DEGs) detected in this assay, 4308 were specifically expressed in the A-NIL which brings superior alleles, and 2463 were expressed specifically in the B-NIL which brings inferior alleles. These DEGs reflect different responses of the two types of NILs to varying N supplies, which likely involve LN-induced root growth. Conclusions: These results explain the better-developed root system and increased root vitality provided by the superior alleles of QMrl-7B and provide a deeper understanding of the genetic underpinnings of root traits, pointing to a valuable locus suitable for future breeding efforts for sustainable agriculture.

scholarly journals Inoculation with the mycorrhizal fungus Rhizophagus irregularis modulates the relationship between root growth and nutrient content in maize (Zea mays ssp. mays L.)

2019 ◽  
Author(s):  
M. Rosario Ramírez-Flores ◽  
Elohim Bello-Bello ◽  
Rubén Rellán-Álvarez ◽  
Ruairidh J. H. Sawers ◽  
Víctor Olalde-Portugal
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Root Growth ◽  
Nutrient Uptake ◽  
Root System ◽  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Root Systems ◽  
Plant Host ◽  
Mycorrhizal Plants ◽  
The Impact

ABSTRACTPlant root systems play an essential role in nutrient and water acquisition. In resource-limited soils, modification of root system architecture is an important strategy to optimize plant performance. Most terrestrial plants also form symbiotic associations with arbuscular mycorrhizal fungi to maximize nutrient uptake. In addition to direct delivery of nutrients, arbuscular mycorrhizal fungi benefit the plant host by promoting root growth. Here, we aimed to quantify the impact of arbuscular mycorrhizal symbiosis on root growth and nutrient uptake in maize. Inoculated plants showed an increase in both biomass and the total content of twenty quantified elements. In addition, image analysis showed mycorrhizal plants to have denser, more branched root systems. For most of the quantified elements, the increase in content in mycorrhizal plants was proportional to root and overall plant growth. However, the increase in boron, calcium, magnesium, phosphorus, sulfur and strontium was greater than predicted by root system size alone, indicating fungal delivery to be supplementing root uptake.

Sign in / Sign up

Export Citation Format

Share Document