Isolation, characterization and associative N-fixation of acid-tolerant Azospirillum brasilense strains associated with Eleusine coracana in low pH-Al-rich acid soil

1991 ◽  
pp. 663-671 ◽  
Author(s):  
Raman Rai
Keyword(s):  
Azospirillum Brasilense ◽  
Acid Soil ◽  
Low Ph ◽  
Eleusine Coracana ◽  
N Fixation ◽  
Acid Tolerant

Manganese-mediated resistance to aluminium and antibiotics in strains ofAzospirillum brasilenseand their interaction with rice genotypes in acid soil

1986 ◽  
Vol 106 (2) ◽  
pp. 279-285 ◽  
Author(s):  
R. Rai
Keyword(s):  
Growth Medium ◽  
Azospirillum Brasilense ◽  
Nitrogenase Activity ◽  
Acid Soil ◽  
Low Ph ◽  
Cross Resistance ◽  
Low Level ◽  
Resistance To Antibiotics ◽  
Rice Genotypes ◽  
The Stability

SUMMARYManganese-tolerant strains Mnr-1 and Mnr-5 ofAzospirillum brasilense(RAU 1075) were isolated through step-wise transfer to higher levels of manganese chloride. One of the strains (Mnr-5) showed more growth at low pH and greater nitrogenase activity in 10 mM MnCl2. 4H2O than parental and Mnr-1 strains. These tolerant strains also showed cross-resistance to antibiotics such as gentamycin and neomycin but not to streptomycin. Mn-adapted strains also tolerated elevated levels of aluminium (2·5–3·5 mg/kg) and the stability of the Mn-resistance required the presence of Mn2+ ions in the growth medium. It has been demonstrated that the effect of inoculation with Mn-adapted strains was variable with different genotypes of rice in acid soil and that initial low level of nitrogen was essential for maximum associative N2-fixation.

scholarly journals Acid tolerance in early colonizers of oral biofilms

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Gabriella Boisen ◽  
Julia R. Davies ◽  
Jessica Neilands
Keyword(s):  
Acid Tolerance ◽  
Low Ph ◽  
Salivary Proteins ◽  
Confocal Scanning Laser Microscopy ◽  
Planktonic Cells ◽  
Tolerance Development ◽  
Salivary Pellicle ◽  
Oral Biofilms ◽  
Acid Tolerant

Abstract Background In caries, low pH drives selection and enrichment of acidogenic and aciduric bacteria in oral biofilms, and development of acid tolerance in early colonizers is thought to play a key role in this shift. Since previous studies have focussed on planktonic cells, the effect of biofilm growth as well as the role of a salivary pellicle on this process is largely unknown. We explored acid tolerance and acid tolerance response (ATR) induction in biofilm cells of both clinical and laboratory strains of three oral streptococcal species (Streptococcus gordonii, Streptococcus oralis and Streptococcus mutans) as well as two oral species of Actinomyces (A. naeslundii and A. odontolyticus) and examined the role of salivary proteins in acid tolerance development. Methods Biofilms were formed on surfaces in Ibidi® mini flow cells with or without a coating of salivary proteins and acid tolerance assessed by exposing them to a challenge known to kill non-acid tolerant cells (pH 3.5 for 30 min) followed by staining with LIVE/DEAD BacLight and confocal scanning laser microscopy. The ability to induce an ATR was assessed by exposing the biofilms to an adaptation pH (pH 5.5) for 2 hours prior to the low pH challenge. Results Biofilm formation significantly increased acid tolerance in all the clinical streptococcal strains (P < 0.05) whereas the laboratory strains varied in their response. In biofilms, S. oralis was much more acid tolerant than S. gordonii or S. mutans. A. naeslundii showed a significant increase in acid tolerance in biofilms compared to planktonic cells (P < 0.001) which was not seen for A. odontolyticus. All strains except S. oralis induced an ATR after pre-exposure to pH 5.5 (P < 0.05). The presence of a salivary pellicle enhanced both acid tolerance development and ATR induction in S. gordonii biofilms (P < 0.05) but did not affect the other bacteria to the same extent. Conclusions These findings suggest that factors such as surface contact, the presence of a salivary pellicle and sensing of environmental pH can contribute to the development of high levels of acid tolerance amongst early colonizers in oral biofilms which may be important in the initiation of caries.

scholarly journals Uji Pendahuluan Genotipe-genotipe Kedelai Hasil Seleksi In Vitro terhadap Cekaman Aluminium dan pH Rendah

2016 ◽  
Vol 1 (2) ◽  
pp. 73
Author(s):  
Arief Vivi Noviati ◽  
Sri Hutami ◽  
Ika Mariska ◽  
Endang Sjamsudin
Keyword(s):  
Yield Components ◽  
Aluminum Toxicity ◽  
Acid Soil ◽  
Acid Soils ◽  
Mutation Breeding ◽  
Low Ph ◽  
Al Tolerance ◽  
Major Constraint ◽  
Gamma Irradiated

<p class="p1">Aluminum toxicity is a major constraint to soybean production in acid soils. Since variabilities on Al tolerance in plants are very limited, mutation breeding, and <em>in vitro </em>selection were used to increase the variability. Three soyben genotypes were produced from cultivars Wilis and Sindoro that have been gamma irradiated and selected <em>in vitro </em>for their tolerance to Al on Al and low pH media. These genotypes and their original cultivars were then planted in a greenhouse in an acid soil on May 2001. The results showed that the plant performances were varied, some were shorter and more compact than the original. Based on the yield components, a number of plants from the genotypes showed higher than those of the control cultivars. These plants were considered more tolerant to Al than the original cultivars.</p>

scholarly journals UJI KETAHANAN TERHADAP ALUMINIUM DAN pH RENDAH PADA JAGUNG (Zea mays L) VARIETAS PIONEER DAN SRIKANDI SECARA IN VITRO

1970 ◽  
Vol 2 (3) ◽  
pp. 292-299
Author(s):  
Sri Romaito Dalimunthe ◽  
Abdullah Bin Arif ◽  
Irpan Badrul Jamal
Keyword(s):  
Acid Soil ◽  
Low Ph ◽  
Leaf Length ◽  
Al Toxicity ◽  
Marginal Land ◽  
Maize Productivity ◽  
Maize Varieties ◽  
Relative Root Length ◽  
Relative Root

One effort to increase maize productivity is by using marginal land for maize plantation. The marginal land that can be used is acid soil, but the problem are Al toxicity and low pH. To cope with these problems, cultivars having tolerance to Al toxicity and low pH are needed. Plant material used in this research were two maize varieties (Pioneer and Srikandi). Media selection is used there are 4 doses treatment aluminium (0, 250, 500 and 750 ppm AlCl3). All variables were observed except at the variable width of the leaf in this results showed that the treatment of aluminium (AlCl3) would not influence. Treatment combination Variety Srikandi and 250 ppm AlCl3 produces plant height, leaf length and leaf width is the shortest compared to other treatments. Variety Pioneer and Srikandi are suspected of varieties resistant aluminum and low pH values based on relative root length.

Application of Methanobrevibacter acididurans in anaerobic digestion

2004 ◽  
Vol 50 (6) ◽  
pp. 109-114 ◽  
Author(s):  
D.V. Savant ◽  
D.R. Ranade
Keyword(s):  
Fatty Acids ◽  
Anaerobic Digestion ◽  
Methane Production ◽  
Volatile Fatty Acids ◽  
Low Ph ◽  
Anaerobic Digesters ◽  
Hydrogenotrophic Methanogen ◽  
Distillery Wastewater ◽  
Acid Tolerant ◽  
Acidic Conditions

To operate anaerobic digesters successfully under acidic conditions, hydrogen utilizing methanogens which can grow efficiently at low pH and tolerate high volatile fatty acids (VFA) are desirable. An acid tolerant hydrogenotrophic methanogen viz. Methanobrevibacter acididurans isolated from slurry of an anaerobic digester running on alcohol distillery wastewater has been described earlier by this lab. This organism could grow optimally at pH 6.0. In the experiments reported herein, M. acididurans showed better methanogenesis under acidic conditions with high VFA, particularly acetate, than Methanobacterium bryantii, a common hydrogenotrophic inhabitant of anaerobic digesters. Addition of M. acididurans culture to digesting slurry of acidogenic as well as methanogenic digesters running on distillery wastewater showed increase in methane production and decrease in accumulation of volatile fatty acids. The results proved the feasibility of application of M. acididurans in anaerobic digesters.

scholarly journals Iron Transformations Induced by an Acid-Tolerant Desulfosporosinus Species

2011 ◽  
Vol 78 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Doug Bertel ◽  
John Peck ◽  
Thomas J. Quick ◽  
John M. Senko
Keyword(s):  
Mine Drainage ◽  
Low Ph ◽  
Content Type ◽  
X Ray ◽  
First Order ◽  
Geochemical Conditions ◽  
Sulfate Reducing ◽  
Mineral Phases ◽  
Magnetic Analysis ◽  
Acid Tolerant

ABSTRACTThe mineralogical transformations of Fe phases induced by an acid-tolerant, Fe(III)- and sulfate-reducing bacterium,Desulfosporosinussp. strain GBSRB4.2 were evaluated under geochemical conditions associated with acid mine drainage-impacted systems (i.e., low pH and high Fe concentrations). X-ray powder diffractometry coupled with magnetic analysis by first-order reversal curve diagrams were used to evaluate mineral phases produced by GBSRB4.2 in media containing different ratios of Fe(II) and Fe(III). In medium containing Fe predominately in the +II oxidation state, ferrimagnetic, single-domain greigite (Fe3S4) was formed, but the addition of Fe(III) inhibited greigite formation. In media that contained abundant Fe(III) [as schwertmannite; Fe8O8(OH)6SO4·nH2O], the activities of strain GBSRB4.2 enhanced the transformation of schwertmannite to goethite (α-FeOOH), due to the increased pH and Fe(II) concentrations that resulted from the activities of GBSRB4.2.

A soil fungus tolerant to extreme acidity and high salt concentrations

1974 ◽  
Vol 20 (7) ◽  
pp. 1023-1027 ◽  
Author(s):  
W. D. Gould ◽  
J. I. Fujikawa ◽  
F. D. Cook
Keyword(s):  
Soil Fungus ◽  
Optimal Growth ◽  
Low Ph ◽  
High Salt ◽  
Acid Tolerant

An extremely acid-tolerant fungus in the genus Scytalidium was isolated from a soil of very low pH. Optimal growth of the fungus occurred between pH 1.0 and 2.0. The fungus tolerated acid concentrations of 2.0 N and salt concentrations up to and including 1.0 M. Growth in the presence of acids was affected primarily by the anion present but in high salt concentrations, no trends were apparent. Other isolates resembling this fungus have been obtained from similar environments, indicating that this species may be common to very acid environments.

scholarly journals Selection and evaluation the corn lines from multiple-cross progeny based on targeted selection environment on acid soil

2021 ◽  
Vol 911 (1) ◽  
pp. 012016
Author(s):  
A Nur ◽  
M Riadi ◽  
A Yassi ◽  
M Farid ◽  
M F Anshori ◽  
...  
Keyword(s):  
Acid Soil ◽  
Block Design ◽  
Population Diversity ◽  
F1 Hybrids ◽  
South Sulawesi ◽  
Randomized Block Design ◽  
Multiple Cross ◽  
Acid Tolerant ◽  
Block Based ◽  
Augmented Design

Abstract Development of tolerant variety can be conducted in the targeted area. It will increase efficiency in producing the acid-tolerant lines. However, the availability of diversity is key in selection. Multiple crosses or crosses between F1 hybrids can be one approach in creating high population diversity. Therefore, the development and selection of offspring of the selfing 1 generation from a cross of two hybrids can be a solution in producing tolerant lines. This study aimed to select multiple-cross maize lines in the generation S1 in an acidic environment. The research was carried out from August to November 2019 at the Maros Cereal Research Center, South Sulawesi. This study was designed with an Augmented Design as an experimental design and a randomized block design as an environmental design. The lines used consisted of 100 S1 lines from crosses of NK7328/HJ28 that did not repeat and six comparison varieties, namely NK7328, HJ28, Sukmaraga, Srikandi Kuning, Bima-9, and Piooner 36 repeated in each block. Based on the results of this study, the evaluation of maize S1 lines under acid soil showed a good variability, especially on generative traits. The ear weight is the best secondary character supported the Grain weight per Ear as the main character. The result of selection showed that 20 S1 lines recommended to selfing cross for continued on the next generation.

Response of sweet potato cultivars to acid soil infertility factors. I. Effects of solution pH on early growth

2000 ◽  
Vol 51 (1) ◽  
pp. 23 ◽  
Author(s):  
V. P. Ila'ava ◽  
C. J. Asher ◽  
F. P. C. Blamey
Keyword(s):  
Root Growth ◽  
Sweet Potato ◽  
Ipomoea Batatas ◽  
Acid Soil ◽  
Chemical Properties ◽  
Early Growth ◽  
Low Ph ◽  
Potato Cultivars ◽  
Stem Cuttings ◽  
Solution Ph

Sweet potato [Ipomoea batatas (L.) Lam.] is cultivated on soils varying widely in chemical properties, but relatively little is known about the effects of pH on the growth of this crop. In commercial and subsistence agriculture, sweet potato is propagated mostly from stem cuttings. This paper reports effects of a range of pH treatments (3.5–8.0) in flowing solution culture on early growth from cuttings of 15 sweet potato cultivars. Root growth was either greatly reduced or inhibited at pH 3.5. Increasing the pH to 4.0 markedly increased root development. Further increases in solution pH from 4.0 to 8.0 did not appear to affect root growth in most cultivars. Top growth in most cultivars showed a tendency to increase when pH was increased from 3.5 to 5.5 before declining with further increases in solution pH. The sweet potato cultivars studied differed widely in their tolerance to low pH, producing 16–48% of maximum top dry mass at pH 3.5. Tissue analysis from selected cultivars showed that K and Ca appeared to be limiting at pH 3.5, while P may have been deficient at pH 8.0. Results of this study indicate that low pH per se does not appear to be a major factor responsible for poor sweet potato yields in acid soils.

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