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1.
Dioumacor Fall Mohamed Ourarhi Mustapha Missbah El Idrissi Niokhor Bakhoum Alzouma Mayaki Zoubeirou Hanaa Abdelmoumen Diégane Diouf 《Symbiosis (Philadelphia, Pa.)》2011,54(2):87-94
The combined effects of drought and salinity were investigated on the growth, efficiency and competitiveness of three Mesorhizobium sp. strains (ORS 3416, ORS 3428 and ORS 3437) isolated from Acacia senegal (L.) Willd. Sixteen combinations of polyethylene glycol (PEG) 6000 (0, 6, 12, 20%, w/v) and NaCl (0.005, 0.5, 1, 1.5%, w/v) were used to study rhizobial strains growth in screw-capped tubes containing yeast extract mannitol liquid medium. Whatever
the combination, the strains grew. However, high concentrations of PEG 6000 and NaCl were depressed on rhizobial growth but
strain ORS 3428 was the most tolerant. The effect of rhizobial inoculation on growth of A. senegal plants was also examined under non-limited (100% of water holding capacity, WHC) and water-limited conditions (50% WHC) in
the greenhouse for 4 months on non-sterile sandy soil. A significant decrease in the nodulation rate, nodule dry weight, plant
height and shoot dry weight was observed under water-limited conditions. Nevertheless, inoculation with the three selected
Mesorhizobium strains significantly improved nodulation and A. senegal plant growth under water-limited conditions. Whatever the irrigation condition, strains ORS 3428 and ORS 3437 were more competitive
than ORS 3416. These rhizobial strains may prove valuable for inoculation of Acacia senegal plants grown for transplantation to dry saline habitats. 相似文献
2.
Humberto J. O. Ramos Emanuel M. Souza Juliana R. L. Soares-Ramos Fábio O. Pedrosa 《World journal of microbiology & biotechnology》2007,23(5):713-717
A new broad-host-range vector expressing constitutively the reporter genes gfp and gusA was used to evaluate nodule occupancy of Phaseolus vulgaris nodules by Rhizobium tropici. The results showed that the pHRGFPGUS plasmid was stably maintained in R. tropici over 45 generations and can therefore be used in nodule competitiveness assays. A new method for determining the nodule occupancy
using the green fluorescent protein as a marker is described and is shown to be quick, inexpensive and reliable. 相似文献
3.
Diouf D Samba-Mbaye R Lesueur D Ba AT Dreyfus B de Lajudie P Neyra M 《Microbial ecology》2007,54(3):553-566
The occurrence and the distribution of rhizobial populations naturally associated to Acacia seyal Del. were characterized in 42 soils from Senegal. The diversity of rhizobial genotypes, as characterized by polymerase chain
reaction restriction fragment length polymorphism (RFLP) analysis of 16S–23S rDNA, performed on DNA extracted from 138 nodules
resulted in 15 clusters. Results indicated the widespread occurrence of compatible rhizobia associated to A. seyal in various ecogeographic areas. However, the clustering of rhizobial populations based on intergenic spacer (IGS) RFLP profiles
did not reflect their geographic origin. Four genera were discriminated on the basis of 16S rRNA gene sequences of the strains
representative for the IGS-RFLP profiles. The majority of rhizobia associated to A. seyal were affiliated to Mesorhizobium and Sinorhizobium 64 and 29%, respectively, of the different IGS-RFLP profiles. Our results demonstrate the coexistence inside the nodule of
plant-pathogenic non-N2-fixing Agrobacterium and Burkholderia strains, which induced the formation of ineffective nodules, with symbiotic rhizobia. Nodulation was recorded in saline soils
and/or at low pH values or in alkaline soils, suggesting adaptability of natural rhizobial populations to major ecological
environmental stress and their ability to establish symbiotic associations within these soil environments. These results contribute
to the progressing research efforts to uncover the biodiversity of rhizobia and to improve nitrogen fixation in agroforestry
systems in sub-Saharan Africa. 相似文献
4.
AR Torres G Kaschuk GP Saridakis M Hungria 《World journal of microbiology & biotechnology》2012,28(4):1831-1835
Brazil has succeeded in sustaining production of soybean [Glycine max (L.) Merrill] by relying mainly on symbiotic N2 fixation, thanks to the selection and use in inoculants of very effective strains of Bradyrhizobium japonicum and Bradyrhizobium elkanii. It is desirable that rhizobial strains used in inoculants have stable genetic and physiological traits, but experience confirms
that rhizobial strains nodulating soybean often lose competitiveness in the field. In this study, soybean cultivar BR 16 was
single-inoculated with four B. japonicum strains (CIAT 88, CIAT 89, CIAT 104 and CIAT 105) under aseptic conditions. Forty colonies were isolated from nodules produced
by each strain. The progenitor strains, the isolates and four other commercially recommended strains were applied separately
to the same cultivar under controlled greenhouse conditions. We observed significant variability in nodulation, shoot dry
weight, shoot total N, nodule efficiency (total N mass over nodule mass) and BOX-PCR fingerprinting profiles between variant
and progenitor strains. Some variant strains resulted in significantly larger responses in terms of shoot total N, dry weight
and nodule efficiency, when compared to their progenitor strain. These results highlight the need for intermittent evaluation
of stock bacterial cultures to guarantee effective symbiosis after inoculation. Most importantly, it indicates that it is
possible to improve symbiotic effectiveness by screening rhizobial strains for higher N2 fixation capacity within the natural variability that can be found within each progenitor strain. 相似文献
5.
The success of rhizobial inoculation on plant roots is often limited by several factors, including environmental conditions,
the number of infective cells applied, the presence of competing indigenous (native) rhizobia, and the inoculation method.
Many approaches have been taken to solve the problem of inoculant competition by naturalized populations of compatible rhizobia
present in soil, but so far without a satisfactory solution. We used antibiotic resistance and molecular profiles as tools
to find a reliable and accurate method for competitiveness assay between introduced Bradyrhizobium sp. strains and indigenous rhizobia strains that nodulate peanut in Argentina. The positional advantage of rhizobia soil
population for nodulation was assessed using a laboratory model in which a rhizobial population is established in sterile
vermiculite. We observed an increase in nodule number per plant and nodule occupancy for strains established in vermiculite.
In field experiments, only 9% of total nodules were formed by bacteria inoculated by direct coating of seed, whereas 78% of
nodules were formed by bacteria inoculated in the furrow at seeding. In each case, the other nodules were formed by indigenous
strains or by both strains (inoculated and indigenous). These findings indicate a positional advantage of native rhizobia
or in-furrow inoculated rhizobia for nodulation in peanut. 相似文献
6.
Nodules from mungbean crop raised for the first time at Ram Dhan Singh (RDS) farm of Chaudhary Charan Singh (CCS) Haryana
Agricultural University, Hisar were collected from 17 different locations. Twenty-five mungbean rhizobia were isolated and
authenticated by plant infection test. DNA of all these rhizobia was extracted purified and amplified using enterobacterial
repetitive intergenic consensus (ERIC) primers. All the mungbean rhizobial isolates were clustered into 4 groups at 65% of
similarity and were further divided into 17 subclusters at 80% of similarity. All the 4 types of rhizobia were not present
at any of the location and group 2 or 4 rhizobia were invariably present. Efficacy of these rhizobia in terms of nodulation,
nitrogen uptake and chlorophyll a fluorescence was determined under pot culture conditions. Strain MB 307 showed maximum nitrogen uptake of 31.9 mg N plant−1 followed by strain MB 1205, MB 1206(2), MB 308, MB 1524 and strain MB 1521 was found to be the least efficient in terms of
N 2 fixation. Nodule occupancy by different rhizobia ranged from 5.5 to 40.3%. Most of the strains belonging to the 2nd group
which clustered maximum number of strains were comparatively better competitors and formed 19.5–40.3% of the nodules and were
also effective. Isolate MB 307, the most efficient strain, was found to have nodule occupancy of 31.5%. Such type of predominant,
efficient and better competitor strains should be selected for enhancing nodule competitiveness. 相似文献
7.
Santi M. Mandal Mahitosh Mandal Amit K. Das Bikas R. Pati Ananta K. Ghosh 《Archives of microbiology》2009,191(4):389-393
The influence of endogenous root nodules phenolic acids on indoleacetic acid (IAA) production by its symbiont (Rhizobium) was examined. The root nodules contain higher amount of IAA and phenolic acids than non-nodulated roots. Presence of IAA
metabolizing enzymes, IAA oxidase, peroxidase, and polyphenol oxidase indicate the metabolism of IAA in the nodules and roots.
Three most abundant endogenous root nodule phenolic acids (protocatechuic acid, 4-hydroxybenzaldehyde and p-coumaric acid) have been identified and their effects on IAA production by the symbiont have been studied in l-tryptophan supplemented yeast extract basal medium. Protocatechuic acid (1.5 μg ml−1) showed maximum stimulation (2.15-fold over control) of IAA production in rhizobial culture. These results indicate that
the phenolic acids present in the nodule might serve as a stimulator for IAA production by the symbiont (Rhizobium).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
8.
Julio C. Vicario Emiliano D. Primo Marta S. Dardanelli Walter Giordano 《Journal of Plant Growth Regulation》2016,35(2):413-419
The ability of inoculated rhizobial strains to increase root nodulation of host legumes often depends on their competitiveness with existing native soil strains. Results of studies to date on rhizobial inoculation for improvement of peanut (Arachis hypogaea L.) production in Argentina have been inconsistent and controversial. In many cases, nodulation and yield of peanut crops have been increased by inoculation of specific rhizobial strains. Native peanut-nodulating strains are generally present in soils of agricultural areas, but their growth-promoting effect is often lower than that of inoculated strains. Many species of the genus Bradyrhizobium interact in a host-specific manner with legume species and form nitrogen-fixing root nodules. Other free-living rhizobacteria such as species of the genus Azospirillum are facultatively capable of interacting with legume roots and promoting plant growth. We evaluated and compared the effects of various single inoculation and co-inoculation treatments on peanut growth parameters in greenhouse and field experiments. In the greenhouse studies, co-inoculation with various Bradyrhizobium strains (native 15A and PC34, and recommended peanut inoculant C145), and Azospirillum brasilense strain Az39 generally resulted in increases in the measured parameters. The growth-promoting effect of 15A was similar to or higher than that of C145. In the field studies, 15A-Az39 co-inoculation had a greater promoting effect on measured growth parameters than did C145-Az39 co-inoculation. Our findings indicate that careful selection of native rhizobacterial strains adapted to peanut soils is useful in strategies for growth promotion, and that 15A in particular is a promising candidate for future inoculant formulation. 相似文献
9.
Fatma Tajini Jean-Jacques Drevon Lazhar Lamouchi Mohamed Elarbi Aouani Mustapha Trabelsi 《World journal of microbiology & biotechnology》2008,24(3):407-417
Since Phaseolus vulgaris (L) is poorly nodulated in all regions of Tunisia where this crop is grown, the response of common-bean lines CocoT and Flamingo
to inoculation with reference Rhizobium tropici CIAT 899 or native rhizobia, namely Sinorhizobium fredii 1a6, Rhizobium etli 12a3, and Rhizobium gallicum 8a3, was studied in a field station. Since R. etli 12a3 was found to be the most effective native rhizobium, it was subsequently compared with R. tropici CIAT 899 in a broader study in two stations over 3 years. A significant interaction between bean and rhizobia was observed
for nodule number, shoot dry weight, grain yield, and contents of nitrogen and chlorophyll. The native rhizobia was more efficient
than CIAT899 for Flamingo, though not for CocoT. The Enzyme-linked immunosorbent assay technique was used with polyclonal
antibody to assess the occupancy in nodule and persistence in soil of the inoculated rhizobia. For both stations the nodule
occupancy was 100% during the first year for each rhizobium, but during the next 2 years, between 7 and 15% of nodules were
formed by the rhizobia inoculated in the neighboring plot. It is concluded that the first-year inoculation is sufficient to
maintain an adequate rate of nodulation during three growth cycles, and that the native R etli can be recommended for the common-bean inoculation in similar soils of Tunisia. 相似文献
10.
Bo Xie Dasong Chen Guojun Cheng Zhengzhou Ying Fuli Xie Youguo Li Junchu Zhou 《Current microbiology》2009,59(2):193-198
Purine pathway in Rhizobium is important during the nodulation processes. The purL gene in Sinorhizobium fredii (S. fredii) has been identified to be required for the whole establishment of a nitrogen-fixing nodule. To get a better understanding
of the purL gene’s impacts on Rhizobium–plant interaction, the competitive nodulation abilities of S. fredii containing different purL expression plasmids were studied. Several kinds of coinoculations were performed, including using different bacterial concentration
ratios, with or without the supplementation of purine source in the plant nutrient solution, and the delayed coinoculation
tests. The results indicated that the competitive nodule occupancy of S. fredii was affected significantly by the purL expression level during the early nodulation periods. The mutant strain containing no purL expression could not elicit competitive nodules both in the presence and absence of purine source. A positive linear correlation
within certain limits was observed between strain’s competitive nodule occupancy and purL gene expression level. All these results suggested that the purL gene played a role in the competitive nodulation of S. fredii. 相似文献
11.
Symbiotic effectiveness of 19 indigenous and two exotic (USDA 2426 and USDA 2431) strains of lentil Rhizobium belonging to different phage-sensitive and phage-resistant groups was compared under axenic condition. Four strains (USDA
2431, BHULR 104, BHULR 113, and BHULR 115) sensitive to different phages were found significantly superior over others in
terms of nodule number, acetylene reduction activity, and total dry weight per plant. Inoculation response of these strains
was then evaluated on six lentil cultivars under field condition. A significant symbiotic interaction between rhizobial strains
and lentil cultivars was observed. Grain yield enhancement was noticed by the compatible interaction of lentil cultivars HUL-57,
L-4147, K-75, and PL-4/DPL-15/DPL-62 with rhizobial strains USDA 2431, BHULR 104, BHULR 113, and BHULR 115, respectively.
The authentication of rhizobial strains was accomplished through 16S rDNA sequence analysis. All rhizobial strains had close
matching with R. leguminosarum bv. viciae strains. The results have shown that phages can trustfully help selecting out the symbiotically efficient most rhizobial
strains for advantageous use with lentil cultivars, in order to strengthen the BNF-based future lentil breeding programs. 相似文献
12.
Reda A. I. Abou-Shanab Manoosak Wongphatcharachai Craig C. Sheaffer James C. Orf Michael J. Sadowsky 《Symbiosis (Philadelphia, Pa.)》2017,73(3):155-163
Organic farmers recognize the importance of rhizobial associations with legume plants to help meet N fertility and plant productivity needs. A field experiment was done at three organic fields in Minnesota to assess the effect of indigenous Bradyrhizobium japonicum ORGS3 and ORGS5 and reference USDA 110 strains on the growth and yield performance of soybean. Soybean genotypes MN1505SP and Lambert inoculated with B. japonicum ORGS3 had significantly greater (P < 0.01) nodule numbers (42.1 ± 2.5), herbage N-contents (4.02 ± 0.01%), dry biomass (12.60 ± 1.45 g), and plant populations (117,890 ± 288.13 plant/acre) compared with the un-inoculated control. Grain yields were not affected by inoculation. Most nodules formed on non-inoculated Lambert (70%) and MN1505SP (53%) were occupied by strain ORGS5. The inoculant strains USDA110 and ORGS5 increased nodule occupancy by 10% on MN1505SP and Lambert. In contrast, strain ORGS3, and the combination of strains ORGS5 plus ORGS3, increased nodules occupancy on Lambert by 23 and 20%, respectively, compared with the control. The majority of nodules on Lambert (59%) and MN1505SP (52%) in the Farmington and Lamberton fields, respectively, were occupied by ORGS5. In contrast, 41 and 45% of nodules formed on Lambert and MN1505SP at Rosemount, respectively, were occupied by strain ORGS3. The lowest percentage of nodules formed on Lambert (4%) and MN1505SP (5%), in the Farmington field, were occupied by USDA110. These results showed that Bradyrhizobium strains ORGS3 and ORGS5 can be used to enhance N fixation and productivity of organically-grown soybeans grown in Minnesota fields. 相似文献
13.
Gutiérrez-Lomelí M Torres-Guzmán JC González-Hernández GA Cira-Chávez LA Pelayo-Ortiz C Ramírez-Córdova Jde J 《Antonie van Leeuwenhoek》2008,93(4):363-371
This work assessed the effect of the overexpression of ADH1 and HXT1 genes in the Saccharomyces cerevisiae AR5 strain during fermentation of Agave tequilana Weber blue variety must. Both genes were cloned individually and simultaneously into a yeast centromere plasmid. Two transformant
strains overexpressing ADH1 and HXT1 individually and one strain overexpressing both genes were randomly selected and named A1, A3 and A5 respectively. Overexpression
effect on growth and ethanol production of the A1, A3 and A5 strains was evaluated in fermentative conditions in A. tequilana Weber blue variety must and YPD medium. During growth in YPD and Agave media, all the recombinant strains showed lower cell
mass formation than the wild type AR5 strain. Adh enzymatic activity in the recombinant strains A1 and A5 cultivated in A. tequilana and YPD medium was higher than in the wild type. The overexpression of both genes individually and simultaneously had no
significant effect on ethanol formation; however, the fermentative efficiency of the A5 strain increased from 80.33% to 84.57%
and 89.40% to 94.29% in YPD and Agave medium respectively. 相似文献
14.
A lectin was isolated from the roots of Sesbania aculeata. This is a glucose specific lectin having 39 kDa subunit molecular weight. The expression of this lectin was found to be
developmentally regulated and observed to be the highest in the second week. The lectin was purified by affinity chromatography
using Sephadex G-50 and found to have 28% homology with Arabidopsis thaliana lectin-like protein (accession No. CAA62665). The lectin binds with lipopolysaccharide isolated from different rhizobial
strains indicating the plants interaction with multiple rhizobial species.
Published in Russian in Biokhimiya, 2009, Vol. 74, No. 3, pp. 404–411. 相似文献
15.
Twenty six Rhizobium strains isolated from root nodules of Sesbania sesban were studied for chitinase activity on chitin agar plates. Among them, only 12 strains showed chitinase activity. The strain
showing the highest chitinase activity was selected based on maximum clear zone/colony size ratio on chitin agar plates and
chitinase activity in culture filtrate. The strain was identified as Rhizobium sp. which showed a high degree of similarity with Rhizobium radiobacter (= Agrobacterium radiobacter). The cultural and nutritional conditions were optimized for maximum chitinase activity. The Rhizobium sp. exhibited maximum chitinase activity after 36 h of incubation, at neutral pH. Among the different nutritional sources,
arabinose and yeast extract were found to be good inducers for chitinase activity. Rhizobium sp. could degrade and utilize dead mycelia of Aspergillus flavus, Aspergillus niger, Curvularia lunata, Fusarium oxysporum and Fusarium udum. 相似文献
16.
Rhizobium–legume symbiotic interaction is an efficient model system for soil remediation and reclamation. We earlier isolated an arsenic
(As) (2.8 mM arsenate) tolerant and symbiotically effective Rhizobium strain, VMA301 from Vigna mungo and in this study we further characterized its efficacy for arsenic removal from the soil and its nitrogen fixation capacity.
Although nodule formation is delayed in plants with As-treated composite when the inoculum was prepared without arsenic in
culture medium, whereas it attains the significant number of nodules compare to plant grown in As-free soil when the inoculum
was prepared with arsenic supplemented medium. Arsenic accumulation was higher in roots than root nodules. Nitrogenase activity
is reduced to almost 2 fold in plants with As-treated soil but not abolished. These results suggest that this strain, VMA301,
has been able to establish an effective symbiotic interaction in V. mungo in As-contaminated soil and can perform dual role of arsenic bioremediation as well as soil nitrogen improvement. 相似文献
17.
Forty-six Rhizobium isolates from legume root and stem nodules were examined for their phosphate-solubilizing ability on Pikovskaya’s agar medium.
Rhizobium isolates from root nodules of Cassia absus, Vigna trilobata and three strains from Sesbania sesban showed zone of tricalcium phosphate (TCP) solubilization. The isolate from C. absus showed maximum solubilization (620 μg/ml) after 12 d of incubation, while the Rhizobium sp. strain 26 (from S. sesban) showed the least amount (150 μg/ml) of phosphate solubilization. Among the carbon sources tested for their ability to solubilize
TCP, maximum solubilization (620 μg/ml) was observed in glucose by Rhizobium isolate from C. absus. Phosphate solubilization increased with increase in glucose concentration steeply up to 2% and slowly
above this concentration in four isolates. Among the nitrogen sources tested, maximum solubilization (620 μg/ml) was observed
in ammonium sulphate by Rhizobium isolate from C. absus. 相似文献
18.
Mingjia Yang Xiangming Xie Caixia Zheng Fangqiu Zhang Xiaoqing He Zhiru Li 《Plant Cell, Tissue and Organ Culture》2008,95(2):141-147
A protocol was developed for Agroacterium-mediated genetic transformation of Acacia crassicarpa via organogenesis by using in vitro phyllode (leaf) as the explant. Phyllode (leaf) explants were co-cultured with Agrobacterium tumefaciens strain LBA4404 harbouring binary vector pBI101 (harboring antisense Pt4CL1 with respect to the Pt4CL1P promoter). The selection for transgenic shoots was performed through two consecutive steps on
Murashige and Skoog (MS) medium supplemented with different concentrations of plant growth regulators and antibiotics in the
following order: 0.5 mg/l thidiazuron (TDZ), 0.5 mg/l α-naphthaleneacetic acid (NAA), 300 mg/l carbenicillin (Car) and 20 mg/l
kanamycin (Km) for 10 days; 0.1 mg/l TDZ, 200 mg/l Car and 20 mg/l Km for 60 days; 0.5 mg/l indole-3-butyric acid (IBA), 100 mg/l
Car and 20 mg/l Km 50 days. 21.7% of nodules produced multiple adventitious shoot buds, of which 27.7% survived in initial
selection. The shoot buds were subjected to repeated selection on MS medium supplemented with 0.1 mg/l TDZ, 200 mg/l Car and
20 mg/l Km for 60 days. Transgenic plants were obtained after rooting on half-strength MS medium supplemented with 0.5 mg/l
IBA, 100 mg/l Car 20 mg/l Km 50 days. Genomic PCR analysis confirmed the incorporation of the antisense Pt4CL1 with respect to the Pt4CL1P promoter fragment into the host genome. 相似文献
19.
20.
KiBeom Lee 《World journal of microbiology & biotechnology》2007,23(9):1317-1320
Lactobacillus
delbrueckii subsp. lactis strains were developed having increased activity, by gradually acclimatizing the bacteria to acidic conditions over repeated
batch culture. Cells from one batch culture were used as the inoculum for the subsequent batch culture and thereby an adapted
strain of Lactobacillus was obtained showing improved lactic acid productivity, cell growth and total glucose utilization. Furthermore, the acclimatized
cells used significantly less nitrogen for a given level of lactic acid production, which is significant from an industrial
point of view. The developed procedure decreases fermentation time and nutrient use, leading to reduced operation costs, while
providing a lactic acid yield superior to previously reported methods. 相似文献