scholarly journals Is there genetic variation in mycorrhization ofMedicago truncatula?

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3713 ◽  
Author(s):  
Dorothée Dreher ◽  
Heena Yadav ◽  
Sindy Zander ◽  
Bettina Hause
Keyword(s):  
Genetic Diversity ◽  
Molecular Markers ◽  
Lateral Roots ◽  
Primary Root ◽  
Arbuscular Mycorrhizal ◽  
Root System Architecture ◽  
Mycorrhizal Colonization ◽  
Independent Experiment ◽  
Fungal Colonization

Differences in the plant’s response among ecotypes or accessions are often used to identify molecular markers for the respective process. In order to analyze genetic diversity ofMedicago truncatulain respect to interaction with the arbuscular mycorrhizal (AM) fungusRhizophagus irregularis, mycorrhizal colonization was evaluated in 32 lines of the nested core collection representing the genetic diversity of the SARDI collection. All studied lines and the reference line Jemalong A17 were inoculated withR. irregularisand the mycorrhization rate was determined at three time points after inoculation. There were, however, no reliable and consistent differences in mycorrhization rates among all lines. To circumvent possible overlay of potential differences by use of the highly effective inoculum, native sandy soil was used in an independent experiment. Here, significant differences in mycorrhization rates among few of the lines were detectable, but the overall high variability in the mycorrhization rate hindered clear conclusions. To narrow down the number of lines to be tested in more detail, root system architecture (RSA) ofin vitro-grown seedlings of all lines under two different phosphate (Pi) supply condition was determined in terms of primary root length and number of lateral roots. Under high Pi supply (100 µM), only minor differences were observed, whereas in response to Pi-limitation (3 µM) several lines exhibited a drastically changed number of lateral roots. Five lines showing the highest alterations or deviations in RSA were selected and inoculated withR. irregularisusing two different Pi-fertilization regimes with either 13 mM or 3 mM Pi. Mycorrhization rate of these lines was checked in detail by molecular markers, such as transcript levels ofRiTubulinandMtPT4. Under high phosphate supply, the ecotypes L000368 and L000555 exhibited slightly increased fungal colonization and more functional arbuscules, respectively. To address the question, whether capability for mycorrhizal colonization might be correlated to general invasion by microorganisms, selected lines were checked for infection by the root rot causing pathogen,Aphanoymces euteiches. The mycorrhizal colonization phenotype, however, did not correlate with the resistance phenotype upon infection with two strains ofA. euteichesas L000368 showed partial resistance and L000555 exhibited high susceptibility as determined by quantification ofA. euteichesrRNA within infected roots. Although there is genetic diversity in respect to pathogen infection, genetic diversity in mycorrhizal colonization ofM. truncatulais rather low and it will be rather difficult to use it as a trait to access genetic markers.

scholarly journals AT-HOOK MOTIF NUCLEAR LOCALISED PROTEIN 18 as a Novel Modulator of Root System Architecture

2020 ◽  
Author(s):  
Marek Šírl ◽  
Tereza Šnajdrová ◽  
Dolores Gutiérrez-Alanís ◽  
Joseph G. Dubrovsky ◽  
Jean Phillipe Vielle-Calzada ◽  
...  
Keyword(s):  
Root System ◽  
System Architecture ◽  
Lateral Root ◽  
Apical Meristem ◽  
Lateral Roots ◽  
Primary Root ◽  
Root System Architecture ◽  
Root Apical Meristem ◽  
Root Initiation ◽  
Lateral Root Initiation

The AT-HOOK MOTIF NUCLEAR LOCALIZED PROTEIN (AHL) gene family encodes embryophyte-specific nuclear proteins with DNA binding activity. They modulate gene expression and affect various developmental processes in plants. We identify AHL18 (At3G60870) as a developmental modulator of root system architecture and growth. AHL18 regulates the length of the proliferation domain and number of dividing cells in the root apical meristem and thereby, cell production. Both primary root growth and lateral root development respond according to AHL18 transcription level. The ahl18 knock-out plants show reduced root systems due to a shorter primary root and a lower number of lateral roots. This change results from a higher number of arrested and non-developing lateral root primordia (LRP) rather than from decreased initiation. Overexpression of AHL18 results in a more extensive root system, longer primary roots, and increased density of lateral root initiation events. Formation of lateral roots is affected during the initiation of LRP and later development. AHL18 regulate root apical meristem activity, lateral root initiation and emergence, which is in accord with localization of its expression.

scholarly journals Early development and gravitropic response of lateral roots in Arabidopsis thaliana

2012 ◽  
Vol 367 (1595) ◽  
pp. 1509-1516 ◽  
Author(s):  
S. Guyomarc'h ◽  
S. Léran ◽  
M. Auzon-Cape ◽  
F. Perrine-Walker ◽  
M. Lucas ◽  
...  
Keyword(s):  
Lateral Root ◽  
Developmental Plasticity ◽  
Lateral Roots ◽  
Expression Patterns ◽  
Primary Root ◽  
Root System Architecture ◽  
Specific Response ◽  
Root Induction ◽  
Root Gravitropism ◽  
Auxin Transporter

Root system architecture plays an important role in determining nutrient and water acquisition and is modulated by endogenous and environmental factors, resulting in considerable developmental plasticity. The orientation of primary root growth in response to gravity (gravitropism) has been studied extensively, but little is known about the behaviour of lateral roots in response to this signal. Here, we analysed the response of lateral roots to gravity and, consistently with previous observations, we showed that gravitropism was acquired slowly after emergence. Using a lateral root induction system, we studied the kinetics for the appearance of statoliths, phloem connections and auxin transporter gene expression patterns. We found that statoliths could not be detected until 1 day after emergence, whereas the gravitropic curvature of the lateral root started earlier. Auxin transporters modulate auxin distribution in primary root gravitropism. We found differences regarding PIN3 and AUX1 expression patterns between the lateral root and the primary root apices. Especially PIN3, which is involved in primary root gravitropism, was not expressed in the lateral root columella. Our work revealed new developmental transitions occurring in lateral roots after emergence, and auxin transporter expression patterns that might explain the specific response of lateral roots to gravity.

Arbuscular Mycorrhizal Colonization Status in Selected Alien Invasive Plants of Asteraceae

2021 ◽  
Vol 9 (2) ◽  
pp. 81-84
Author(s):  
M.C. Freddy Vanlalmuana ◽  
◽  
Lalmuan puia ◽  
Kripamoy Chakraborty ◽  
R. Lalfakzuala ◽  
...  
Keyword(s):  
Invasive Plants ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Mycorrhizal Colonization ◽  
Fungal Colonization ◽  
Ageratum Conyzoides ◽  
Bidens Pilosa ◽  
Mikania Micrantha ◽  
Non Invasive ◽  
Alien Invasive Plants

Invasive alien plants tend to grow much faster than non-invasive plants. The colonization by AM fungi is confirmed by the presence of mycorrhizal structures in the roots of invasive plants. The pattern of hyphae and arbuscules denotes Arum and Paris type of AM fungal morphology. The most common and abundant invasive plants from Asteraceae family were selected for the study. Ageratum conyzoides, Mikania micrantha, Ageratum haustonianum and Bidens Pilosa were selected and eventually showed that they have a high percentage of mycorrhizal colonization. Arum type of morphology is found in three of the plant species and Paris type of morphology is found in one of the species. The extent of AM fungal colonization is fairly high ranging from 60% to 90% among the studied plants. The percentage of arbuscular colonization is highest in Bidens pilosa and the percentage of vesicle and hyphal colonization is highest in Ageratum conyzoides.

scholarly journals Nitric oxide effect on root architecture development in Malus seedlings

2011 ◽  
Vol 57 (No. 9) ◽  
pp. 418-422 ◽  
Author(s):  
H.J. Gao ◽  
H.Q. Yang
Keyword(s):  
Nitric Oxide ◽  
Root Architecture ◽  
Lateral Roots ◽  
Primary Root ◽  
Root System Architecture ◽  
Dependent Manner ◽  
Lateral Root Primordia ◽  
Architecture Development ◽  
Two Peaks ◽  
Dose Dependent

 The time-dependent production of nitric oxide (NO) in roots induced by indole-3-butyric acid (IBA) and the effect of sodium nitroprusside (SNP) on root architecture development were investigated, using Malus hupehensis Rehd. seedlings. Following IBA application, a very rapid increase in NO formation and a subsequent second wave of NO burst was observed, which was related to the induction of lateral roots (LRs) and the organogenesis of lateral root primordia (LRP), respectively. The first NO burst was correlated with the second and the two peaks of NO burst induced by IBA were totally abolished by 3,3’,4’,5,7-pentahydroxyflavone (quercetin). Exogenous NO promoted the emergence and elongation of LR and inhibited the elongation of primary root (PR) in a dose-dependent manner: low concentrations of SNP promoted both the amounts and the elongation of LR but inhibited the elongation of LR and PR at higher concentrations. It was concluded that (i) the rapid production of NO induced by IBA was correlated with the IBA-induced initiation of LR; (ii) quercetin inhibition of IBA-induced LR formation was correlated with the quercetin inhibition of IBA-induced NO biosynthesis, and (iii) exogenous NO affects the development of root system architecture in a dose-dependent manner.

scholarly journals Solanum lycopersicum Seedlings. Metabolic Responses Induced by the Alkamide Affinin

Metabolites ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 143
Author(s):  
Tonatiu Campos-García ◽  
Jorge Molina-Torres
Keyword(s):  
Metabolic Pathways ◽  
Lateral Roots ◽  
Primary Root ◽  
Mitochondrial Electron Transport Chain ◽  
Metabolomic Analysis ◽  
Tomato Seedlings ◽  
Relieve Pain ◽  
Transport Chain ◽  
Primary Root Length

Alkamides have been observed to interact in different ways in several superior organisms and have been used in traditional medicine in many countries e.g., to relieve pain. Previous studies showed that affinin when applied to other plant species induces prominent changes in the root architecture and induces transcriptional adjustments; however, little is known about the metabolic pathways recruited by plants in response to alkamides. Previous published work with Arabidopsis seedlings treated in vitro with affinin at 50 µM significantly reduced primary root length. In tomato seedlings, that concentration did not reduce root growth but increase the number and length of lateral roots. Non-targeted metabolomic analysis by Gas Chromatography couplet to Mass Spectrometry (GC/EIMS) showed that, in tomato seedlings, affinin increased the accumulation of several metabolites leading to an enrichment of several metabolic pathways. Affinin at 100 µM alters the accumulation of metabolites such as organic acids, amino acids, sugars, and fatty acids. Finally, our results showed a response possibly associated with nitrogen, GABA shunt and serine pathways, in addition to a possible alteration in the mitochondrial electron transport chain (ETC), interesting topics to understand the molecular and metabolic mechanisms in response to alkamide in plants.

scholarly journals Analysis of Root System Architecture Affected by Swarming Behavior

2020 ◽  
Vol 28 (1) ◽  
pp. 1-12
Author(s):  
Songyang Li ◽  
Wenqi Yu ◽  
Xiaodong Liu ◽  
Miao Wang
Keyword(s):  
Root System ◽  
System Architecture ◽  
Root Length ◽  
Lateral Roots ◽  
Primary Root ◽  
Morphological Characteristics ◽  
Root System Architecture ◽  
Behavior Model ◽  
Single Root ◽  
Swarming Behavior

AbstractThe root system architecture (RSA) displays complex morphological characteristics because of diverse root growth behaviors. Recent studies have revealed that swarming behavior among roots is particularly important for RSA to adapt to environmental stimuli. However, few models are proposed to simulate RSA based on swarming behavior of roots. To analyze plasticity of RSA affected by swarming behavior, we propose viewing it as a swarm of single roots. A swarming behavior model is proposed by considering repulsion, alignment, and preference of individual single roots. Then, the swarming behavior model is integrated into a simple and generic RSA model (called ArchiSimple). Lastly, characteristics of RSA affected by swarming behavior model and non-swarming behavior model are compared and analyzed under three different virtual soil sets. The characteristics of RSA (such as primary root length, lateral root length, lateral roots, and resource uptake) are significantly promoted by swarming behavior. Root system distributions can also be greatly affected by swarming behavior. These results show that root foraging and exploration in soil can be regarded as collective behavior of individual single root.

scholarly journals Disruption of CYCLOPHILIN 38 function reveals a photosynthesis-dependent systemic signal controlling lateral root emergence

2020 ◽  
Author(s):  
Lina Duan ◽  
Juan Manuel Pérez-Ruiz ◽  
Francisco Javier Cejudo ◽  
José R. Dinneny
Keyword(s):  
Root Growth ◽  
Root System ◽  
Lateral Root ◽  
System Development ◽  
Lateral Roots ◽  
Primary Root ◽  
Root System Architecture ◽  
Minor Effect ◽  
Low Light ◽  
Primary Root Growth

AbstractPhotosynthesis in leaves generates the fixed-carbon resources and essential metabolites that support sink tissues, such as roots [1]. One of these products, sucrose, is known to promote primary root growth, but it is not clear what other molecules may be involved and whether other stages of root system development are affected by photosynthate levels [2]. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the CYCLOPHILIN 38 (CYP38) gene, which causes an accumulation of pre-emergent stage lateral roots, with a minor effect on primary root growth. CYP38 was previously reported to maintain the stability of Photosystem II (PSII) in chloroplasts [3]. CYP38 expression is enriched in the shoot and grafting experiments show that the gene acts non-cell autonomously to promote lateral root emergence. Growth of wild-type plants under low light conditions phenocopied the cyp38 lateral root emergence phenotype as did the inhibition of PSII-dependent electron transport or NADPH production. Importantly, the cyp38 root phenotype is not rescued by exogenous sucrose, suggesting the involvement of another metabolite. Auxin (IAA) is an essential hormone promoting root growth and its biosynthesis from tryptophan is dependent on reductant generated during photosynthesis [4,5]. Both WT seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. The cyp38 lateral root defect is rescued by IAA treatment, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. Metabolomic profiling shows that the accumulation of several defense-related metabolites are also photosynthesis-dependent, suggesting that the regulation of a number of energy-intensive pathways are down-regulated when light becomes limiting.

scholarly journals Systemic signalling through TCTP1 controls lateral root formation in Arabidopsis

2019 ◽  
Author(s):  
Rémi Branco ◽  
Josette Masle
Keyword(s):  
Lateral Root ◽  
Developmental Plasticity ◽  
Lateral Roots ◽  
Primary Root ◽  
Root System Architecture ◽  
Dual Function ◽  
Growth Promoter ◽  
Lateral Organs ◽  
Root Organogenesis

AbstractAs in animals, the plant body plan and primary organs are established during embryogenesis. However, plants have the ability to generate new organs and functional units throughout their whole life. These are produced through the specification, initiation and differentiation of secondary meristems, governed by the intrinsic genetic program and cues from the environment. They give plants an extraordinary developmental plasticity to modulate their size and architecture according to environmental constraints and opportunities. How this plasticity is regulated at the whole organism level is still largely elusive. In particular the mechanisms regulating the iterative formation of lateral roots along the primary root remain little known. A pivotal role of auxin is well established and recently the role of local mechanical signals and oscillations in transcriptional activity has emerged. Here we provide evidence for a role of Translationally Controlled Tumor Protein (TCTP), a vital ubiquitous protein in eukaryotes. We show that Arabidopsis AtTCTP1 controls root system architecture through a dual function: as a general constitutive growth promoter locally, and as a systemic signalling agent via mobility from the shoot. Our data indicate that this signalling function is specifically targeted to the pericycle and modulates the frequency of lateral root initiation and emergence sites along the primary root, and the compromise between branching and elongating, independent of shoot size. Plant TCTP genes show high similarity among species. TCTP messengers and proteins have been detected in the vasculature of diverse species. This suggests that the mobility and extracellular signalling function of AtTCTP1 to control root organogenesis might be widely conserved within the plant kingdom, and highly relevant to a better understanding of post-embryonic formation of lateral organs in plants, and the elusive coordination of shoot and root morphogenesis.

scholarly journals Isolation of a Premycorrhizal Infection (pmi2) Mutant of Tomato, Resistant to Arbuscular Mycorrhizal Fungal Colonization

2003 ◽  
Vol 16 (5) ◽  
pp. 382-388 ◽  
Author(s):  
Rakefet David-Schwartz ◽  
Vijay Gadkar ◽  
Smadar Wininger ◽  
Roza Bendov ◽  
Gad Galili ◽  
...  
Keyword(s):  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizae ◽  
Glomus Intraradices ◽  
Arbuscular Mycorrhizal ◽  
Plant Roots ◽  
Fungal Colonization ◽  
Recessive Trait ◽  
Wild Type ◽  
Arbuscular Mycorrhizal Fungal

Arbuscular mycorrhizae (AM) represent an ancient symbiosis between mycorrhizal fungi and plant roots which co-evolved to exhibit a finely tuned, multistage interaction that assists plant growth. Direct screening efforts for Myc¯ plant mutants resulted in the identification of a tomato (Lycopersicon esculentum L. cv. Micro-Tom) mutant, M20, which was impaired in its ability to support the premycorrhizal infection (pmi) stages. The Myc¯ phenotype of the M20 mutant was a single Mendelian recessive trait, stable for nine generations, and nonallelic to a previously identified M161 pmi mutant. The M20 mutant was resistant to infection by isolated AM spores and colonized roots. Formation of Glomus intraradices appressoria on M20 roots was normal, as on wild-type (WT) plants, but in significantly reduced numbers. A significant reduction in spore germination was observed in vitro in the presence of M20 exudates relative to WT. Our results indicate that this new mutant shares similar physiological characteristics with the M161 pmi mutant, but has a more suppressive Myc¯ phenotype response.

scholarly journals Nucleotide Diversity and Association Analysis of ZmMADS60 with Root Length in the Maize Seedling Stage

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 342
Author(s):  
Pengcheng Li ◽  
Zhenzhen Ge ◽  
Houmiao Wang ◽  
Jie Wei ◽  
Yunyun Wang ◽  
...  
Keyword(s):  
Association Analysis ◽  
Root Length ◽  
Nucleotide Diversity ◽  
Lateral Roots ◽  
Primary Root ◽  
Root System Architecture ◽  
Inbred Lines ◽  
Seedling Stage ◽  
Functional Markers ◽  
Maize Domestication

Root length is a determining factor of the root system architecture, which is essential for the uptake of water, nutrients and plant anchorage. In this study, ZmMADS60 was resequenced in 285 inbred lines, 68 landraces and 32 teosintes to detect the nucleotide diversity and natural variations associated with root length. Nucleotide diversity and neutral tests revealed that ZmMADS60 might be selected in domestication and improvement processes. ZmMADS60 in maize retained only 40.1% and 66.9% of the nucleotide diversity found in teosinte and landrace, respectively. Gene-based association analysis of inbred lines identified nine variants that were significantly associated with primary root length (PRL), lateral root length (LRL), root length between 0 mm and 0.5 mm in diameter (RL005) and total root length (TRL). One single-nucleotide polymorphism SNP1357 with pleiotropic effects was significantly associated with LRL, RL005 and TRL. The frequency of the increased allele T decreased from 68.8% in teosintes to 52.9% and 38.9% in the landrace and inbred lines, respectively. The frequency of the increased allele of another significant SNP723 associated with PRL also decreased during the maize domestication and improvement processes. The results of this study reveal that ZmMADS60 may be involved in the elongation of primary and lateral roots in the seedling stage and that significant variants can be used to develop functional markers to improve root length in maize.

Sign in / Sign up

Export Citation Format

Share Document