scholarly journals Oilseed Rape Cultivars Show Diversity of Root Morphologies with the Potential for Better Capture of Nitrogen

Nitrogen ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 491-505
Author(s):  
László Kupcsik ◽  
Claudia Chiodi ◽  
Taraka Ramji Moturu ◽  
Hugues De Gernier ◽  
Loïc Haelterman ◽  
...  

The worldwide demand for vegetable oils is rising. Oilseed rape (Brassica napus) diversifies cereal dominated crop rotations but requires important nitrogen input. Yet, the root organ is offering an untapped opportunity to improve the nitrogen capture in soil. This study evaluates three culture systems in controlled environment, to observe root morphology and to identify root attributes for superior biomass production and nitrogen use. The phenotypic diversity in a panel of 55 modern winter oilseed rape cultivars was screened in response to two divergent nitrate supplies. Upon in vitro and hydroponic cultures, a large variability for root morphologies was observed. Root biomass and morphological traits positively correlated with shoot biomass or leaf area. The activities of high-affinity nitrate transport systems correlated negatively with the leaf area, while the combined high- and low-affinity systems positively with the total root length. The X-ray computed tomography permitted to visualize the root system in pipes filled with soil. The in vitro root phenotype at germination stage was indicative of lateral root deployment in soil-grown plants. This study highlights great genetic potential in oilseed rape, which could be manipulated to optimize crop root characteristics and nitrogen capture with substantial implications for agricultural production.

2002 ◽  
Vol 68 (7) ◽  
pp. 3328-3338 ◽  
Author(s):  
Gabriele Berg ◽  
Nicolle Roskot ◽  
Anette Steidle ◽  
Leo Eberl ◽  
Angela Zock ◽  
...  

ABSTRACT To study the effect of plant species on the abundance and diversity of bacterial antagonists, the abundance, the phenotypic diversity, and the genotypic diversity of rhizobacteria isolated from potato, oilseed rape, and strawberry and from bulk soil which showed antagonistic activity towards the soilborne pathogen Verticillium dahliae Kleb. were analyzed. Rhizosphere and soil samples were taken five times over two growing seasons in 1998 and 1999 from a randomized field trial. Bacterial isolates were obtained after plating on R2A (Difco, Detroit, Mich.) or enrichment in microtiter plates containing high-molecular-weight substrates followed by plating on R2A. A total of 5,854 bacteria isolated from the rhizosphere of strawberry, potato, or oilseed rape or bulk soil from fallow were screened by dual testing for in vitro antagonism towards Verticillium. The proportion of isolates with antagonistic activity was highest for strawberry rhizosphere (9.5%), followed by oilseed rape (6.3%), potato (3.7%), and soil (3.3%). The 331 Verticillium antagonists were identified by their fatty acid methyl ester profiles. They were characterized by testing their in vitro antagonism against other pathogenic fungi; their glucanolytic, chitinolytic, and proteolytic activities; and their BOX-PCR fingerprints. The abundance and composition of Verticillium antagonists was plant species dependent. A rather high proportion of antagonists from the strawberry rhizosphere was identified as Pseudomonas putida B (69%), while antagonists belonging to the Enterobacteriaceae (Serratia spp., Pantoea agglomerans) were mainly isolated from the rhizosphere of oilseed rape. For P. putida A and B plant-specific genotypes were observed, suggesting that these bacteria were specifically enriched in each rhizosphere.


2003 ◽  
Vol 134 (1) ◽  
pp. 388-400 ◽  
Author(s):  
Philippe Malagoli ◽  
Philippe Lainé ◽  
Erwan Le Deunff ◽  
Laurence Rossato ◽  
Bertrand Ney ◽  
...  

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 349
Author(s):  
Dominik Bleša ◽  
Pavel Matušinský ◽  
Romana Sedmíková ◽  
Milan Baláž

The use of biological control is becoming a common practice in plant production. One overlooked group of organisms potentially suitable for biological control are Rhizoctonia-like (Rh-like) fungi. Some of them are capable of forming endophytic associations with a large group of higher plants as well as mycorrhizal symbioses. Various benefits of endophytic associations were proved, including amelioration of devastating effects of pathogens such as Fusarium culmorum. The advantage of Rh-like endophytes over strictly biotrophic mycorrhizal organisms is the possibility of their cultivation on organic substrates, which makes their use more suitable for production. We focused on abilities of five Rh-like fungi isolated from orchid mycorrhizas, endophytic fungi Serendipita indica, Microdochium bolleyi and pathogenic Ceratobasidium cereale to inhibit the growth of pathogenic F. culmorum or Pyrenophora teres in vitro. We also analysed their suppressive effect on wheat infection by F. culmorum in a growth chamber, as well as an effect on barley under field conditions. Some of the Rh-like fungi affected the growth of plant pathogens in vitro, then the interaction with plants was tested. Beneficial effect was especially noted in the pot experiments, where wheat plants were negatively influenced by F. culmorum. Inoculation with S. indica caused higher dry shoot biomass in comparison to plants treated with fungicide. Prospective for future work are the effects of these endophytes on plant signalling pathways, factors affecting the level of colonization and surviving of infectious particles.


Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1441
Author(s):  
Youssef Chebli ◽  
Samira El Otmani ◽  
Mouad Chentouf ◽  
Jean-Luc Hornick ◽  
Jean-François Cabaraux

Forest rangelands contribute largely to goat diets in the Mediterranean area. Information about browsed plant quality is essential for adequate feeding management. The purpose of this study was to evaluate the temporal changes in chemical composition and in vitro digestibility of the main plant species selected by goats in the Southern Mediterranean forest rangeland during two consecutive years; these were very contrasted (dry and wet). The browsed species were composed of herbaceous, eleven shrubs, and four tree species. Overall, large variability in chemical composition, in vitro organic matter digestibility (IVOMD), and metabolizable energy (ME) was observed among species, grazing season (spring, summer, and autumn), and years within each species. Crude protein (CP) content varied from 60 to 240 g/kg dry matter (DM). The fiber fractions, except for Quercus suber, increased significantly by advancing maturity. Due to the water stress, the lignin level presented a higher value during the spring of the dry year. Condensed tannin (CT) content varied from 2 to 184 g/kg DM. CP, IVOMD, and ME showed a negative correlation with lignin and CT. Based on the results presented herein, it is concluded that the nutritive value of the browsed plant species was highest in the spring and lowest during the summer and autumn of both studied years. With a good grazing management strategy, the selected plant species by goats could guarantee high-quality feeding resources throughout the year.


2021 ◽  
Vol 108 (Supplement_1) ◽  
Author(s):  
I Martin ◽  
Y Wu ◽  
R Patel ◽  
P Kalra ◽  
S Clark K ◽  
...  

Abstract Introduction The lifetime risk of colorectal cancer in familial adenomatous polyposis (FAP) approaches 100%. In patients who have undergone prophylactic colectomy, duodenal cancer is 100-300 times more common than in the general population, and an important cause of death. We aimed to develop in vitro models of mucosal crypt-derived organoids from patients with FAP. Method Biopsies from apparent healthy duodenal mucosa of FAP patients undergoing upper gastrointestinal endoscopy or surgery yielded crypts that were immobilised in Matrigel Basement Membrane Matrix (Corning) and cultured in IntestiCult Organoid Growth Medium (StemCell Technologies) to generate organoids for further morphologic and immunocytochemistry analyses (Dako and Abcam antibodies). Result Duodenal crypt-derived organoids from one healthy volunteer formed ring structures (days 1 -2) that progressed to expected branched structures (days 4-7). FAP-derived organoids from 9 patients all generated organoids with aberrant morphologies. These organoids expressed markers of Paneth cells (lysozyme), proliferation (Ki-67), goblet cells (Muc-2) and the single cell layer of mucosal epithelium (CK18). Conclusion This is the first report of duodenal crypt-derived organoids generated from FAP patients. Aberrant organoid morphologies were observed in all 9 patients. Immunocytochemistry confirmed markers of duodenal epithelium, suggesting a promising in vitro model to study disease aetiology in FAP. Take-home message This is a step towards a personalised model of disease for patients with familial adenomatous polyposis.


1991 ◽  
Vol 260 (3) ◽  
pp. G457-G463 ◽  
Author(s):  
M. Moreto ◽  
C. Amat ◽  
A. Puchal ◽  
R. K. Buddington ◽  
J. M. Planas

We examined the characteristics of amino acid and sugar absorption by the proximal cecum (PC) of chickens during posthatch development. Rates of absorption of L-proline (Pro) and alpha-methyl-D-glucoside (MG) were measured at 2 days, 5 wk, and 13 wk after hatch with an in vitro everted-sleeve method. For each age, pieces of PC and midjejunum were incubated in solutions containing 0.1-50 mM Pro or MG, and the active and passive components of Pro and MG absorption were determined. Five conclusions may be stated. 1) There are two carrier-mediated transport systems for Pro in the PC: a higher capacity Na(+)-dependent system (Vmax between 1.6 and 3.2 nmol.mg-1.min-1), and a lower capacity Na(+)-independent system (Vmax 0.3-0.8 nmol.mg-1.min-1). 2) Whereas both Pro transport systems are present in the PC at 5 and 13 wk, only the Na(+)-dependent system was found at 2 days. Although rates of transport per milligram tissue by the Na(+)-dependent system fell during development, when rates were normalized to nominal surface area, Vmax was significantly higher in the 5-wk-old group than in the other groups. 3) MG transport is by a Na(+)-dependent system. Vmax values (nmol.mg-1.min-1) were 0.32 (2 days), less than 0.43 (5 wk), and = 0.55 (13 wk). These differences were not affected by normalization to surface area. 4) Because at physiological concentrations passive influx of Pro and MG would be negligible, absorption of amino acids and sugars by the PC would be dependent on the presence of carrier-mediated systems.(ABSTRACT TRUNCATED AT 250 WORDS)


2019 ◽  
Vol 20 (10) ◽  
pp. 2435 ◽  
Author(s):  
Tetsuya Takahashi ◽  
Takayoshi Shimohata

Methylmercury (MeHg) causes severe damage to the central nervous system, and there is increasing evidence of the association between MeHg exposure and vascular dysfunction, hemorrhage, and edema in the brain, but not in other organs of patients with acute MeHg intoxication. These observations suggest that MeHg possibly causes blood–brain barrier (BBB) damage. MeHg penetrates the BBB into the brain parenchyma via active transport systems, mainly the l-type amino acid transporter 1, on endothelial cell membranes. Recently, exposure to mercury has significantly increased. Numerous reports suggest that long-term low-level MeHg exposure can impair endothelial function and increase the risks of cardiovascular disease. The most widely reported mechanism of MeHg toxicity is oxidative stress and related pathways, such as neuroinflammation. BBB dysfunction has been suggested by both in vitro and in vivo models of MeHg intoxication. Therapy targeted at both maintaining the BBB and suppressing oxidative stress may represent a promising therapeutic strategy for MeHg intoxication. This paper reviews studies on the relationship between MeHg exposure and vascular dysfunction, with a special emphasis on the BBB.


2020 ◽  
Author(s):  
Delaney Burnard ◽  
Gemma Robertson ◽  
Andrew Henderson ◽  
Caitlin Falconer ◽  
Michelle Bauer-Leo ◽  
...  

AbstractCefiderocol is a novel cephalosporin designed to treat multidrug resistant Gram-negative infections. By forming a chelated complex with ferric iron, cefiderocol is transported into the periplasmic space via bacterial iron transport systems and primarily binds to penicillin-binding protein 3 (PBP3) to inhibit peptidoglycan synthesis. This mode of action results in cefiderocol having greater in vitro activity against many Gram-negative bacilli than currently used carbapenems, β-lactam/β-lactamase inhibitor combinations, and cephalosporins. Thus, we investigated the in vitro activity of cefiderocol (S-649266) against a total of 271 clinical isolates of Burkholderia pseudomallei from Australia. The collection was comprised of primary isolates (92.3%) and subsequent isolates (7.7%). Minimum inhibitory concentrations (MIC) of cefiderocol ranged from ≤0.03 to 32 mg/L, where the MIC90 was 1 mg/L and 16 mg/L for primary and subsequent isolates, respectively. Based upon non-species specific (Gram-negative bacilli) clinical breakpoints for cefiderocol (MIC ≤ 4 mg/L), twelve isolates (4.4%) would be classified as non-susceptible. Further testing for co-resistance to meropenem, ceftazidime, trimethoprim-sulfamethoxazole, amoxicillin-clavulanate and doxycycline was performed on a subset of isolates with elevated cefiderocol MICs (≥2 mg/L, 4.8%) and 84.6% of these isolates exhibited resistance to at least one of these antimicrobials. Cefiderocol was found to be highly active in vitro against B. pseudomallei primary clinical isolates. This novel compound shows great potential for the treatment of melioidosis in endemic countries and should be explored further.


2022 ◽  
Author(s):  
Siu Lung Ng ◽  
Sophia A. Kammann ◽  
Gabi Steinbach ◽  
Tobias Hoffmann ◽  
Peter J. Yunker ◽  
...  

Mutations in regulatory mechanisms that control gene expression contribute to phenotypic diversity and thus facilitate the adaptation of microbes to new niches. Regulatory architecture is often inferred from transcription factor identification and genome analysis using purely computational approaches. However, there are few examples of phenotypic divergence that arise from the rewiring of bacterial regulatory circuity by mutations in intergenic regions, because locating regulatory elements within regions of DNA that do not code for protein requires genomic and experimental data. We identify a single cis-acting single nucleotide polymorphism (SNP) dramatically alters control of the type VI secretion system (T6), a common weapon for inter-bacterial competition. Tight T6 regulatory control is necessary for adaptation of the waterborne pathogen Vibrio cholerae to in vivo conditions within the human gut, which we show can be altered by this single non-coding SNP that results in constitutive expression in vitro. Our results support a model of pathogen evolution through cis-regulatory mutation and preexisting, active transcription factors, thus conferring different fitness advantages to tightly regulated strains inside a human host and unfettered strains adapted to environmental niches.


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