Apical control, gravitropic signaling, and the growth of lateral roots in Arabidopsis

A new technique for Arabidopsis thaliana cultivation has been proposed that combines the use of a phytogel-based nutrient medium and a hydrophilic membrane of hydrate cellulose film, separating the root system of the plant from the medium thickness. Growth rates of both main and lateral roots were faster in the plants cultivated on the surface of hydrate cellulose film than in the plants grown in the phytogel volume. The location of the root system on the surface of the transparent hydrate film simplifies its observation and analysis and facilitates plant transplantation with preservation of the root system configuration. The proposed technique allowed us to first assess the effect of exogenous auxin on the growth of lateral roots at the 5-6 developmental stage. methods to study plant root systems, hydrate cellulose film, A. thaliana, lateral roots, differential root growth rate, auxin The work was financially supported by the Russian Foundation for Basic Research (Project Bel_mol_a 19-54-04015) and the basic topic of the Russian Academy of Sciences - IBMP RAS «Regularities of the Influence of Extreme Environmental Factors on the Processes of Cultivation of Higher Plants and the Development of Japanese Quail Tissues at Different Stages of its Ontogenesis under the Conditions of Regenerative Life Support Systems».

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A Tale of Two Domains Pushing Lateral Roots

Trends in Plant Science ◽

10.1016/j.tplants.2021.01.006 ◽

2021 ◽

Author(s):

Ross Sager ◽

Malcolm Bennett ◽

Jung-Youn Lee

Keyword(s):

Lateral Roots

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A comprehensive RNA-Seq-based gene expression atlas of the summer squash (Cucurbita pepo) provides insights into fruit morphology and ripening mechanisms

BMC Genomics ◽

10.1186/s12864-021-07683-2 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Aliki Xanthopoulou ◽

Javier Montero-Pau ◽

Belén Picó ◽

Panagiotis Boumpas ◽

Eleni Tsaliki ◽

...

Keyword(s):

Gene Expression ◽

Cucurbita Pepo ◽

Developmental Stages ◽

Lateral Roots ◽

Expression Patterns ◽

Male Flower ◽

Differentially Expressed ◽

Gene Expression Atlas ◽

Summer Squash ◽

Expression Atlas

Abstract Background Summer squash (Cucurbita pepo: Cucurbitaceae) are a popular horticultural crop for which there is insufficient genomic and transcriptomic information. Gene expression atlases are crucial for the identification of genes expressed in different tissues at various plant developmental stages. Here, we present the first comprehensive gene expression atlas for a summer squash cultivar, including transcripts obtained from seeds, shoots, leaf stem, young and developed leaves, male and female flowers, fruits of seven developmental stages, as well as primary and lateral roots. Results In total, 27,868 genes and 2352 novel transcripts were annotated from these 16 tissues, with over 18,000 genes common to all tissue groups. Of these, 3812 were identified as housekeeping genes, half of which assigned to known gene ontologies. Flowers, seeds, and young fruits had the largest number of specific genes, whilst intermediate-age fruits the fewest. There also were genes that were differentially expressed in the various tissues, the male flower being the tissue with the most differentially expressed genes in pair-wise comparisons with the remaining tissues, and the leaf stem the least. The largest expression change during fruit development was early on, from female flower to fruit two days after pollination. A weighted correlation network analysis performed on the global gene expression dataset assigned 25,413 genes to 24 coexpression groups, and some of these groups exhibited strong tissue specificity. Conclusions These findings enrich our understanding about the transcriptomic events associated with summer squash development and ripening. This comprehensive gene expression atlas is expected not only to provide a global view of gene expression patterns in all major tissues in C. pepo but to also serve as a valuable resource for functional genomics and gene discovery in Cucurbitaceae.

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High-Resolution Spatiotemporal Water Use Mapping of Surface and Direct-Root-Zone Drip-Irrigated Grapevines Using UAS-Based Thermal and Multispectral Remote Sensing

Remote Sensing ◽

10.3390/rs13050954 ◽

2021 ◽

Vol 13 (5) ◽

pp. 954

Author(s):

Abhilash K. Chandel ◽

Lav R. Khot ◽

Behnaz Molaei ◽

R. Troy Peters ◽

Claudio O. Stöckle ◽

...

Keyword(s):

High Resolution ◽

Water Use ◽

Root Zone ◽

Lateral Roots ◽

Irrigation Treatment ◽

Crop Coefficient ◽

Spatiotemporal Resolution ◽

Site Specific ◽

Canopy Transpiration ◽

Irrigation Treatments

Site-specific irrigation management for perennial crops such as grape requires water use assessments at high spatiotemporal resolution. In this study, small unmanned-aerial-system (UAS)-based imaging was used with a modified mapping evapotranspiration at high resolution with internalized calibration (METRIC) energy balance model to map water use (UASM-ET approach) of a commercial, surface, and direct-root-zone (DRZ) drip-irrigated vineyard. Four irrigation treatments, 100%, 80%, 60%, and 40%, of commercial rate (CR) were also applied, with the CR estimated using soil moisture data and a non-stressed average crop coefficient of 0.5. Fourteen campaigns were conducted in the 2018 and 2019 seasons to collect multispectral (ground sampling distance (GSD): 7 cm/pixel) and thermal imaging (GSD: 13 cm/pixel) data. Six of those campaigns were near Landsat 7/8 satellite overpass of the field site. Weather inputs were obtained from a nearby WSU-AgWeatherNet station (1 km). First, UASM-ET estimates were compared to those derived from soil water balance (SWB) and conventional Landsat-METRIC (LM) approaches. Overall, UASM-ET (2.70 ± 1.03 mm day−1 [mean ± std. dev.]) was higher than SWB-ET (1.80 ± 0.98 mm day−1). However, both estimates had a significant linear correlation (r = 0.64–0.81, p < 0.01). For the days of satellite overpass, UASM-ET was statistically similar to LM-ET, with mean absolute normalized ET departures (ETd,MAN) of 4.30% and a mean r of 0.83 (p < 0.01). The study also extracted spatial canopy transpiration (UASM-T) maps by segmenting the soil background from the UASM-ET, which had strong correlation with the estimates derived by the standard basal crop coefficient approach (Td,MAN = 14%, r = 0.95, p < 0.01). The UASM-T maps were then used to quantify water use differences in the DRZ-irrigated grapevines. Canopy transpiration (T) was statistically significant among the irrigation treatments and was highest for grapevines irrigated at 100% or 80% of the CR, followed by 60% and 40% of the CR (p < 0.01). Reference T fraction (TrF) curves established from the UASM-T maps showed a notable effect of irrigation treatment rates. The total water use of grapevines estimated using interpolated TrF curves was highest for treatments of 100% (425 and 320 mm for the 2018 and 2019 seasons, respectively), followed by 80% (420 and 317 mm), 60% (391 and 318 mm), and 40% (370 and 304 mm) of the CR. Such estimates were within 5% to 11% of the SWB-based water use calculations. The UASM-T-estimated water use was not the same as the actual amount of water applied in the two seasons, probably because DRZ-irrigated vines might have developed deeper or lateral roots to fulfill water requirements outside the irrigated soil volume. Overall, results highlight the usefulness of high-resolution imagery toward site-specific water use management of grapevines.

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Lateral root formation and nutrients: nitrogen in the spotlight

Plant Physiology ◽

10.1093/plphys/kiab145 ◽

2021 ◽

Author(s):

Pierre-Mathieu Pélissier ◽

Hans Motte ◽

Tom Beeckman

Keyword(s):

Signaling Pathways ◽

Root System ◽

Root Development ◽

Lateral Root ◽

Molecular Mechanisms ◽

Root Formation ◽

Lateral Roots ◽

Nutrient Use Efficiency ◽

Lateral Root Formation ◽

Lateral Root Development

Abstract Lateral roots are important to forage for nutrients due to their ability to increase the uptake area of a root system. Hence, it comes as no surprise that lateral root formation is affected by nutrients or nutrient starvation, and as such contributes to the root system plasticity. Understanding the molecular mechanisms regulating root adaptation dynamics towards nutrient availability is useful to optimize plant nutrient use efficiency. There is at present a profound, though still evolving, knowledge on lateral root pathways. Here, we aimed to review the intersection with nutrient signaling pathways to give an update on the regulation of lateral root development by nutrients, with a particular focus on nitrogen. Remarkably, it is for most nutrients not clear how lateral root formation is controlled. Only for nitrogen, one of the most dominant nutrients in the control of lateral root formation, the crosstalk with multiple key signals determining lateral root development is clearly shown. In this update, we first present a general overview of the current knowledge of how nutrients affect lateral root formation, followed by a deeper discussion on how nitrogen signaling pathways act on different lateral root-mediating mechanisms for which multiple recent studies yield insights.

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Myco-Suppression Analysis of Soybean (Glycine max) Damping-Off Caused by Pythium aphanidermatum

Plants ◽

10.3390/plants10040788 ◽

2021 ◽

Vol 10 (4) ◽

pp. 788

Author(s):

Shaban R. M. Sayed ◽

Shaimaa A. M. Abdelmohsen ◽

Hani M. A. Abdelzaher ◽

Mohammed A. Elnaghy ◽

Ashraf A. Mostafa ◽

...

Keyword(s):

Glycine Max ◽

Biocontrol Agent ◽

Lateral Roots ◽

Dry Weight ◽

Pythium Aphanidermatum ◽

Damping Off ◽

Pythium Oligandrum ◽

Rdna Its ◽

Half Strength

The role of Pythium oligandrum as a biocontrol agent against Pythium aphanidermatum was investigated to avoid the harmful impacts of fungicides. Three isolates of P. oligandrum (MS15, MS19, and MS31) were assessed facing the plant pathogenic P. aphanidermatum the causal agent of Glycine max damping-off. The tested Pythium species were recognized according to their cultural and microscopic characterizations. The identification was confirmed through sequencing of rDNA-ITS regions including the 5.8 S rDNA. The biocontrol agent, P. oligandrum, isolates decreased the mycelial growth of the pathogenic P. aphanidermatum with 71.3%, 67.1%, and 68.7% through mycoparasitism on CMA plates. While the half-strength millipore sterilized filtrates of P. oligandrum isolates degrade the pathogenic mycelial linear growth by 34.1%, 32.5%, and 31.7%, and reduce the mycelial dry weight of the pathogenic P. aphanidermatum by 40.1%, 37.4%, and 36.8%, respectively. Scanning electron microscopy (SEM) of the most effective antagonistic P. oligandrum isolate (MS15) interaction showed coiling, haustorial parts of P. oligandrum to P. aphanidermatum hyphae. Furthermore, P. oligandrum isolates were proven to enhance the germination of Glycine max seedling to 93.3% in damping-off infection using agar pots and promote germination of up to 80% during soil pot assay. On the other hand, P. oligandrum isolates increase the shoot, root lengths, and the number of lateral roots.

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Evidence for nitrate reductase expression during initiation of lateral roots by NAA in chicory

Journal of Experimental Botany ◽

10.1093/jxb/49.323.937 ◽

1998 ◽

Vol 49 (323) ◽

pp. 937-944 ◽

Cited By ~ 4

Author(s):

C. Vuylsteker ◽

E. Prinsen ◽

J.-P. Boutin ◽

H. A. V. Onckelen ◽

S. Rambour

Keyword(s):

Nitrate Reductase ◽

Lateral Roots

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Relationship Between Root and Yield Related Morphological Characters in Pea (Pisum Sativum L.)

Plant Breeding and Seed Science ◽

10.2478/v10129-011-0053-7 ◽

2014 ◽

Vol 66 (1) ◽

pp. 3-15

Author(s):

Sylwia Ciaglo-Androsiuk

Keyword(s):

Root System ◽

Morphological Traits ◽

Lateral Roots ◽

Morphological Characters ◽

Yield Potential ◽

Cultivated Plants ◽

Genetic Determination ◽

Canonical Correlations ◽

Effect On Yield

AbstractRelation between morphological traits of the root system and yield related traits is an important issue concerning efforts aiming at improving of ideotype of cultivated plants species, including pea. In this paper, to analyse the dependency between traits describing the root system morphology and yield potential, Person’s andSpearman's_correlations as well as canonical correlations were used.Root system was analyzed in 14 and 21 day-old seedlings growing in blotting-paper cylinders. Yield potential of pea was analysed in a field experiment. Results of Person’s and Spearman's_correlations revealed that number of lateral roots and lateral roots density were correlated witch yield related traits. Correlation between root length and shoot length was observed only for 14 day-old seedlings. The result of canonical correlations revealed that number of lateral roots and lateral roots density had the largest effect on yield related traits. This work highlights, that in order to improve the yield of pea it might become necessary to understand genetic determination of morphological traits of the root system, especially number of lateral roots.

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Apical control of band elongation in Antithamnion defectum (Ceramiaceae, Rhodophyta)

Canadian Journal of Botany ◽

10.1139/b88-184 ◽

1988 ◽

Vol 66 (7) ◽

pp. 1308-1315 ◽

Cited By ~ 14

Author(s):

David Garbary ◽

Daniel Belliveau ◽

Robert Irwin

Keyword(s):

Cell Elongation ◽

Experimental Conditions ◽

Axial Cell ◽

Wall Deposition ◽

Apical Control ◽

Band Position ◽

Apical Cells ◽

In Cells

Cell elongation in the Ceramiaceae typically occurs by means of one or two bands located apically and (or) basally in each cell. In axial cells of Antithamnion defectum two bands are present; however, most cell elongation occurs as a result of new wall deposition in bands at the base of each axial cell. In cells of determinate branches, only the basal band is present. In experimental conditions in which apical cells of indeterminate branches are differentially excised, location of the primary elongation band can be reestablished in relation to remaining indeterminate axes. Thus, the primary elongation band in axial cells is always basal with respect to indeterminate apical cells. When all indeterminate apices are removed, band growth becomes highly disrupted, and diffuse, irregularly located bands are formed. These results suggest that regulation of band position and elongation is through apical control.

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