Journal articles on the topic 'Nitrogen fixing plants (Australia)'
To see the other types of publications on this topic, follow the link: Nitrogen fixing plants (Australia).
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Nitrogen fixing plants (Australia).'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Schulze, E. D., R. J. Williams, G. D. Farquhar, W. Schulze, J. Langridge, J. M. Miller, and B. H. Walker. "Carbon and nitrogen isotope discrimination and nitrogen nutrition of trees along a rainfall gradient in northern Australia." Functional Plant Biology 25, no. 4 (1998): 413. http://dx.doi.org/10.1071/pp97113.
Abstract:
Carbon isotope discrimination (Δ) and nitrogen isotope ratios, N-concentrations and specific leaf area of 50 tree species were investigated along a continental-scale transect through northern Australia over which annual rainfall varied from 1800 mm to 216 mm rainfall. Average specific leaf area (SLA, m2 kg-1) of leaves ranged from 10.7 ± 1.7 (av. ± s.d.) in N2 fixing deciduous trees to 0.8 ± 0.4 in spinescent sclerophylls shrubs. SLA generally decreased with increasing aridity. N2 fixing species had higher leaf N concentration (average N-concentration 20.1 ± 3.7 mgN g-1) than non- N2 fixing (10.8 ± 3.3) or spinescent species (7.05 ± 1.8). Community-averaged Δ was approximately constant at rainfalls above 475 mm (average Δ = 19.4 ± 1.2‰). Where rainfall was less than 475 mm, Δ decreased from 19‰ to 17‰ at 220 mm. Δ was positively correlated with SLA. Δ of deciduous N2 fixing species and spinescent species were 1‰ and 2.4‰ lower than in evergreen sclerophyllous species. Δ in the N2 fixing Allocasuarina was 1.2‰ lower than in non- N2 fixing sclerophyllous species. The δ15N-values indicated N2 fixation only at high rainfall. Burning of the field layer in a Eucalyptus forest had no effect on all measured tree parameters including δ15N, but δ15N increased under grazing conditions to >5‰. The constant value of community averaged Δ between 1800 and 450 mm may be the result of replacement of functional types and species. The decline in Δ in the more arid section may be a function of both low species diversity, and a highly aseasonal and unpredictable rainfall regime.
2
Milne, Cameron, Stephen J. Trueman, Shahla Hosseini Bai, and Alison Shapcott. "Translocation and population establishment of Schoenus scabripes (Cyperaceae)." Australian Journal of Botany 69, no. 4 (2021): 225. http://dx.doi.org/10.1071/bt20149.
Abstract:
Coastal ecosystems are under increasing pressure from land clearing along the east coast of Australia. Methods to mitigate the impacts of land clearing are needed, particularly for locally uncommon plants. In addition, there are significant knowledge gaps about cultivation methods for many wet-heath sedges. Translocation via salvage and relocation of plant populations is often the only viable ex situ, last-resort conservation option for populations threatened by clearing. We aimed to determine if translocation was an effective method for relocating a wild population of Schoenus scabripes, and how the use of organic mulch or a nitrogen-fixing companion plant affected survival, growth and nutrient concentrations of nursery-grown S. scabripes plants. Whole-plant translocation of S. scabripes plants was effective, with 62% survival at 50 months after installation. Survival of translocated nursery-grown plants was 35% at 27 months after installation. Organic mulch improved survival and health of field-established plants; however, companion plants did not improve plant health or survival. Stem and leaf winter potassium concentrations for mulched plants were significantly higher than for other treatments. Our case study demonstrated two establishment techniques for S. scabripes and suggested that whole-plant translocation of mature clumps is more effective than field establishment of nursery-grown plants.
3
Unkovich, Murray J., John S. Pate, Edward C. Lefroy, and David J. Arthur. "Nitrogen isotope fractionation in the fodder tree tagasaste (Chamaecytisus proliferus) and assessment of N2 fixation inputs in deep sandy soils of Western Australia." Functional Plant Biology 27, no. 10 (2000): 921. http://dx.doi.org/10.1071/pp99201.
Abstract:
Nitrogen (N) isotope fractionation and symbiotic N fixation were investigated in the shrub legume tagasaste, growing in the glasshouse and field. In a pot study of effectively nodulated plants supplied with 0, 1, 5 and 10 mM nitrate [stable isotope 15N (δ15N) of 3.45‰], the δ15N of dry matter N of fully symbiotic cultures indicated a greater isotope fractionation during distribution of N between nodules, stems, leaves and roots than for N2 fixation itself, with whole-plant δ15N being near zero (–0.46 to 0.42‰). Regardless of whether plants were field-grown, pot-cultured, fixing N2 or utilising mineral N, woody stems were depleted in 15N relative to all other plant parts. The similar orders of ranking of δ15N for plant components of the nitrate-treated and fully symbiotic plants, and a general increase in δ15N as plants were exposed to increasing concentrations of nitrate, indicated that N isotope fractionation can be accounted for, and thus not undermine 15N natural abundance as means of measuring N2 fixation inputs in tagasaste trees. In pot culture the percentage of plant N derived from the atmosphere (%Ndfa) by symbiotic N2 fixation fell from 85 to 37% when the nitrate supply was increased from 1 to 10 mM, with evidence of nitrate N being preferentially allocated to roots. δ15N natural abundance assessments of N2 fixation of 4-year-old trees of field-grown tagasaste in alley (550 trees ha-1) or plantation (2330 trees ha-1) spacing were undertaken at a study site at Moora, Western Australia, over a 2-year period of shoot regrowth (coppicing). Cumulative N yields and %Ndfa were similar for trees of alley and plantation spacing, with much less coppice N accumulation in the first compared to the second year after cutting. Scaling values from a tree to plot area basis, and using a mean %Ndfa value of 83% for all trees at the site, inputs of fixed N into current biomass plus fallen litter over the 2 years of coppicing were calculated to be 83 kg N ha-1 year-1 for the alley and 390 kg N ha-1 year-1 for the plantation spacing. Although the plantation tagasaste fixed 587 kg N ha-1 in the second year, close to the maximum value reported in the literature for any N2-fixing system, this should not be seen as typical where the trees are used for animal production, since grazing and cutting management will substantially reduce productivity and N2 fixation input.
4
Bergersen, F. J. "Phillip Sadler Nutman. 10 October 1914 – 4 May 2004." Biographical Memoirs of Fellows of the Royal Society 51 (January 2005): 315–26. http://dx.doi.org/10.1098/rsbm.2005.0020.
Abstract:
Dr Phillip Nutman was a microbiologist and plant physiologist, distinguished for his research into the infection of roots of legumes by root nodule bacteria of the genus Rhizobium. This is a subject that is truly symbiotic, involving both leguminous host plants and free–living soil bacteria, which join in a complex, often specific interaction to produce symbiotic, nodulated, nitrogen–fixing plants. His research pre–dated the molecular genetics now available to modern researchers and used the techniques of plant physiology and Mendelian genetics to explore the mechanisms of infection, subsequent nodule development and the symbiotic fixation of atmospheric nitrogen. The research took place in the laboratories and fields of Rothamsted Experimental Station, Harpenden, Hertfordshire, where the study of nitrogen fixation by nodulated legumes first developed in the UK (Russell 1966). There were components of related research in Australia, 1953–57 (Bergersen 2001), and also in other countries during the International Biological Programme of 1966–73, in which Nutman was an active participant. He was a well–respected leader in active research during a period in which the subject underwent rapid development. In many ways his work became the basis on which more recent research has developed. He was a modest, self–effacing, scrupulously honest man who became increasingly impatient with the methods of research management that were emerging within the Agriculture and Food Research Council towards the end of his career at Rothamsted. After his retirement, in his Personal Record, he wrote critically about these matters.
5
Dinnage, Russell, Anna K. Simonsen, Luke G. Barrett, Marcel Cardillo, Nat Raisbeck-Brown, Peter H. Thrall, and Suzanne M. Prober. "Larger plants promote a greater diversity of symbiotic nitrogen-fixing soil bacteria associated with an Australian endemic legume." Journal of Ecology 107, no. 2 (October 30, 2018): 977–91. http://dx.doi.org/10.1111/1365-2745.13083.
6
Gupta, V. V. S. R., S. J. Kroker, M. Hicks, C. W. Davoren, K. Descheemaeker, and R. Llewellyn. "Nitrogen cycling in summer active perennial grass systems in South Australia: non-symbiotic nitrogen fixation." Crop and Pasture Science 65, no. 10 (2014): 1044. http://dx.doi.org/10.1071/cp14109.
Abstract:
Non-symbiotic nitrogen (N2) fixation by diazotrophic bacteria is a potential source for biological N inputs in non-leguminous crops and pastures. Perennial grasses generally add larger quantities of above- and belowground plant residues to soil, and so can support higher levels of soil biological activity than annual crops. In this study, the hypothesis is tested that summer-active perennial grasses can provide suitable microsites with the required carbon supply for N2 fixation by diazotrophs, in particular during summer, through their rhizosphere contribution. In a field experiment on a Calcarosol at Karoonda, South Australia, during summer 2011, we measured populations of N2-fixing bacteria by nifH-PCR quantification and the amount of 15N2 fixed in the rhizosphere and roots of summer-active perennial grasses. Diazotrophic N2 fixation estimates for the grass roots ranged between 0.92 and 2.35 mg 15N kg–1 root day–1. Potential rates of N2 fixation for the rhizosphere soils were 0.84–1.4 mg 15N kg–1 soil day–1 whereas the amount of N2 fixation in the bulk soil was 0.1–0.58 mg 15N kg–1 soil day–1. Populations of diazotrophic bacteria in the grass rhizosphere soils (2.45 × 106 nifH gene copies g–1 soil) were similar to populations in the roots (2.20 × 106 nifH gene copies g–1 roots) but the diversity of diazotrophic bacteria was significantly higher in the rhizosphere than the roots. Different grass species promoted the abundance of specific members of the nifH community, suggesting a plant-based selection from the rhizosphere microbial community. The results show that rhizosphere and root environments of summer-active perennial grasses support significant amounts of non-symbiotic N2 fixation during summer compared with cropping soils, thus contributing to biological N inputs into the soil N cycle. Some pasture species also maintained N2 fixation in October (spring), when the grasses were dormant, similar to that found in soils under a cereal crop. Surface soils in the rainfed cropping regions of southern Australia are generally low in soil organic matter and thus have lower N-supply capacity. The greater volume of rhizosphere soil under perennial grasses and carbon inputs belowground can potentially change the balance between N immobilisation and mineralisation processes in the surface soils in favour of immobilisation, which in turn contributes to reduced N losses from leaching.
7
Roper, MM, and V. Gupta. "Management-practices and soil biota." Soil Research 33, no. 2 (1995): 321. http://dx.doi.org/10.1071/sr9950321.
Abstract:
The soil biota consist of a large number and range of micro- and macro-organisms and are the living part of soils. They interact with each other and with plants, directly providing nutrition and other benefits. They regulate their own populations as well as those of incoming microorganisms by biological control mechanisms. Microorganisms are responsible for organic matter decomposition and for the transformations of organically bound nitrogen and minerals to forms that are available to plants. Their physical structure and products contribute significantly to soil structure. Management practices have a significant impact on micro- and macro-organism populations and activities. Stubble retention, an increasing trend in Australia, provides an energy source for growth and activity. Significant increases in the sizes and activities of microbial biomass, including heterotrophic microorganisms, cellulolytic microorganisms, nitrogen-fixing bacteria and nitrifying and denitrifying bacteria have been observed. In addition, increases in protozoa and meso- and macro-fauna have been seen. Stubble retention provides a means of maintaining or increasing organic matter levels in soils. The way in which stubbles are managed may impact further on the activities of the soil biota and may alter the population balance, e.g. bacterial:fungal ratios. In general, no-tillage results in a concentration of microorganisms closer to the soil surface and causes least disruption of soil structure compared with conventionally tilled soils. Some plant diseases increase with stubble retention and with no-tillage, particularly where the next crop is susceptible to the same disease as the previous crop. However, the general increase in microbial populations resulting from stubble retention can exclude pathogens through competitive inhibition and predatory and parasitic activity. Cropping sequences may be used to break disease cycles. Crop rotations that include legumes may provide additional nitrogen and stimulate mineralization processes. Coupled with no-tillage in stubble retention systems is an increased usage of herbicides to control weeds. Continued herbicide use has been shown to significantly depress some groups of microorganisms and some of their activities but, in Australia, little information is available about the effects of herbicides on microbial populations. Although we know that micro- and macro-organisms are vital in maintaining ecosystem function, our knowledge about them is still very limited. New techniques in molecular microbial ecology promise further advances. Much more detailed information about the effects of specific managements on the size and activities of populations is needed. Soils and their processes are extremely complex and, in order to develop appropriate management practices, integration of new and existing information is necessary. This is now being made possible through computer simulation modelling.
8
Tang, C., L. Barton, and C. D. A. McLay. "A comparison of proton excretion of twelve pasture legumes grown in nutrient solution." Australian Journal of Experimental Agriculture 37, no. 5 (1997): 563. http://dx.doi.org/10.1071/ea96151.
Abstract:
Summary.The use of legumes to improve the productivity of pastures has usually been associated with an increase in soil acidification. The present study compared the acidification potential of 12 N2-fixing pasture legume species/genotypes using a solution culture assay. The legumes were chosen because of their use or potential use in farming systems in the mediterranean zones of southern Australia. The species grown were Trifolium subterraneum L. (vars. Dalkeith, Yarloop and Clare), Trifolium glomeratum L., Trifolium tomentosum L., Medicago murex Willd., Medicago polymorpha L., Medicago truncatulaGaertn., Ornithopus compressus L., Ornithopus sativusBrot., Trifolium vesiculosum and Trifolium balansae. Proton excretion was measured over a period of 21 days from days 40 to 61 after germination. The amount of protons excreted into solution varied between 143 and 265 cmol H+ /kg dry matter for the different species and genotypes. In general, T. tomentosum and T. glomeratum excreted greater amounts of protons per unit biomass than Medicago species and T. subterraneum, which, in turn, excreted more protons than Ornithopus species. The amount of proton excreted per kilogram biomass was well correlated with the concentrations of excess cations over anions and ash alkalinity in plants across all the species. Total acid production was highly correlated with accumulation of excess cations and ash alkalinity, total dry matter production and total nitrogen fixation during the study period. It is suggested that the potential proton excretion by new pasture legume species should be considered when they are introduced into farming systems.
9
Warrington, Staci, Allan G. Ellis, Jan-Hendrik Keet, and Johannes J. Le Roux. "How does familiarity in rhizobial interactions impact the performance of invasive and native legumes?" NeoBiota 72 (March 28, 2022): 129–56. http://dx.doi.org/10.3897/neobiota.72.79620.
Abstract:
Mutualisms can be disrupted when non-native plants are introduced into novel environments, potentially impacting their establishment success. Introduced species can reassemble mutualisms by forming novel associations with resident biota or by maintaining familiar associations when they are co-introduced with their mutualists. Invasive Australian Acacia species in South Africa have formed nitrogen-fixing rhizobium mutualisms using both pathways. Here we examined the contributions of novel vs familiar rhizobial associations to the performance of Acacia saligna across different soils within South Africa’s Core Cape Subregion (CCR), and the concomitant impacts of exotic rhizobia on the endemic legume, Psoralea pinnata. We grew each legume with and without Australian Bradyrhizobium strains across various CCR soil types in a glasshouse. We identified root nodule rhizobium communities associating with seedlings grown in each treatment combination using next-generation sequencing (NGS) techniques. Our results show that different CCR soils affected growth performances of seedlings for both species while the addition of Australian bradyrhizobia affected growth performances of A. saligna, but not P. pinnata. NGS data revealed that each legume associated mostly with their familiar rhizobial partners, regardless of soil conditions or inoculum treatment. Acacia saligna predominantly associated with Australian bradyrhizobia, even when grown in soils without inoculum, while P. pinnata largely associated with native South African Mesorhizobium strains. Our study suggests that exotic Australian bradyrhizobia are already present and widespread in pristine CCR soils, and that mutualist limitation is not an impediment to further acacia invasion in the region. The ability of P. pinnata to sanction Australian Bradyrhizobium strains suggests that this species may be a good candidate for restoration efforts following the removal of acacias in CCR habitats.
10
Fernandez, Romina D., Sergio J. Ceballos, Agustina Malizia, and Roxana Aragón. "Gleditsia triacanthos (Fabaceae) in Argentina: a review of its invasion." Australian Journal of Botany 65, no. 3 (2017): 203. http://dx.doi.org/10.1071/bt16147.
Abstract:
Gleditsia triacanthos L. is a woody species native to North America that has invaded Uruguay, Spain, Australia, South Africa and several countries of Central and Eastern Europe. In Argentina, it has become one of the most important invasive woody species and has a high potential to continue spreading. In this study, we review different aspects of G. triacanthos invasion in Argentina that include descriptions of invaded ecoregions and environments, intrinsic characteristics of the species, invasion dynamics and impacts. In addition, we discuss mechanisms that potentially explain its success, control strategies and natural barriers to its invasion. We reviewed a total of 91 articles and book chapters, of which 62 were developed in Argentina. Studies reported that the invasion of G. triacanthos in different ecoregions was favoured by intrinsic characteristics of the species, together with the interaction with cattle and disturbances, which cause negative impacts on flora, fauna and ecosystem processes. Disturbances were proposed as the main mechanism to explain this species’ invasion, but other hypotheses such as the release of natural enemies and/or propagule pressure might also be important. Further studies are required, mainly on the impacts on ecosystem processes and on the control, production of organic compounds and mutualistic interactions (with nitrogen-fixing bacteria and mycorrhizal fungi).
11
Good, Allen. "Toward nitrogen-fixing plants." Science 359, no. 6378 (February 22, 2018): 869–70. http://dx.doi.org/10.1126/science.aas8737.
12
Li-Na, WANG, YU Yong-Qiang, LU Dong-Xu, and TANG Ya-Kun. "Soil pH modulates nitrogen transfer from nitrogen-fixing plants to non-nitrogen-fixing plants." Chinese Journal of Plant Ecology 46, no. 1 (2022): 1–17. http://dx.doi.org/10.17521/cjpe.2021.0283.
13
Fahrenkamp-Uppenbrink, Julia. "Can scientists create nitrogen-fixing plants?" Science 359, no. 6378 (February 22, 2018): 880.18–882. http://dx.doi.org/10.1126/science.359.6378.880-r.
14
THOMPSON, VINTON. "Spittlebug indicators of nitrogen-fixing plants." Ecological Entomology 19, no. 4 (November 1994): 391–98. http://dx.doi.org/10.1111/j.1365-2311.1994.tb00257.x.
15
Liang, Yueming, Xunyang He, Xiangbi Chen, Yirong Su, Fujing Pan, and Lening Hu. "Low Frequency of Plants Associated with Symbiotic Nitrogen-Fixers Exhibits High Frequency of Free-Living Nitrogen Fixing Bacteria: A Study in Karst Shrub Ecosystems of Southwest China." Forests 13, no. 2 (January 21, 2022): 163. http://dx.doi.org/10.3390/f13020163.
Abstract:
Plants associated with symbiotic nitrogen-fixers and soil free-living nitrogen-fixing bacteria are good indicators for detecting the source of nitrogen in natural ecosystems. However, the community composition and diversity of plants associated with symbiotic nitrogen-fixers and soil free-living nitrogen-fixing bacteria in karst shrub ecosystems remain poorly known. The community composition and diversity of soil free-living nitrogen-fixing bacteria and plants, as well as the soil physical–chemical properties were investigated in 21 shrub plots (including different topographies and plant types). The frequency of plants associated with symbiotic nitrogen-fixers was found to be low in the 21 shrub plots. The soil free-living nitrogen-fixing bacterial community structure varied among the 21 shrub soils. Based on a variance partitioning analysis, topography, plant type, and soil pH explained 48.5% of the observed variation in bacterial community structure. Plant type had a predominant effect on community structure, and topography (aspect and ascent) and soil pH had minor effects. A negative correlation between the abundance of the soil free-living nitrogen-fixing bacterial community and the richness index for plants associated with symbiotic nitrogen-fixers was observed. The result of the low frequency of plants associated with symbiotic nitrogen-fixers highlights the importance of sources of fixed nitrogen by soil free-living nitrogen-fixing bacteria in the nitrogen limitation shrub ecosystem of the karst regions.
16
Chen, Haoran, Sylvie Renault, and John Markham. "The Effect of Frankia and Hebeloma crustiliniforme on Alnus alnobetula subsp. Crispa Growing in Saline Soil." Plants 11, no. 14 (July 16, 2022): 1860. http://dx.doi.org/10.3390/plants11141860.
Abstract:
The mining of the oil sands region of Canada’s boreal forest creates disturbed land with elevated levels of salts. Understanding how native plants respond to salt stress is critical in reclaiming these lands. The native species, Alnus alnobetula subsp. crispa forms nitrogen-fixing nodules with Frankia, and ectomycorrhizae with a number of fungal species. These relationships may make the plant particularly well suited for restoring disturbed land. We inoculated A. alnobetula subsp. crispa with Frankia and Hebeloma crustiliniforme and exposed the plants to 0, 50, or 100 mM NaCl for seven weeks. Frankia-inoculated plants had increased biomass regardless of salt exposure, even though salt exposure reduced nitrogen fixation and reduced the efficiency of nitrogen-fixing nodules. The nitrogen-fixing symbiosis also decreased leaf stress and increased root phosphatase levels. This suggests that N-fixing plants not only have increased nitrogen nutrition but also have increased access to soil phosphorus. Mycorrhizae did not affect plant growth but did reduce nodule numbers and nodule efficiency. These results suggest that the nitrogen-fixing trait is more critical than mycorrhizae. While salt stress inhibits nitrogen-fixing symbiosis, plants still benefit from nitrogen fixation when exposed to salt.
17
AKAO, Shoichiro, Tadashi YOKOYAMA, and Tadakatsu YONEYAMA. "Communication between Nitrogen-fixing Microbes and Plants." JOURNAL OF THE BREWING SOCIETY OF JAPAN 89, no. 5 (1994): 341–48. http://dx.doi.org/10.6013/jbrewsocjapan1988.89.341.
18
Meeks, John C. "Symbiosis between Nitrogen-Fixing Cyanobacteria and Plants." BioScience 48, no. 4 (April 1998): 266–76. http://dx.doi.org/10.2307/1313353.
19
Sprent, J. I., and J. A. Raven. "Evolution of nitrogen-fixing symbioses." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 85, no. 3-4 (1985): 215–37. http://dx.doi.org/10.1017/s0269727000004036.
Abstract:
SynopsisBecause of both the energy costs and the slowness of the reactions of the nitrogenase complex compared with those involving some form of combined nitrogen (oxidised or reduced), we argue that the evolution of nitrogen-fixing organisms required an environment which was very limited in combined nitrogen. This is thought to have occurred after phototrophy evolved, but before water was used as a hydrogen donor (and therefore oxygen was present in the atmosphere). After oxygenic photosynthesis evolved, the need for a high level of biological nitrogen-fixation remained, since abiotic inputs were insufficient to keep pace with the rapidly evolving biomass (flora and fauna). Symbiotic fixation probably first evolved in the form of casual associations between cyanobacteria and most other groups of plants. By inhabiting the sporophytic generation of evolving land plants (cycads in particular), protection against nitrogenase-inactivating oxygen and a more desiccating environment was achieved simultaneously.We envisage nodulated plants arising by the transfer ofnifgenes into tumour-forming bacteria. In the case of legumes, these would be ancestors of extant agrobacteria, which gain entry into their hostsviawounds. Co-evolution of symbionts from nitrogen-fixing tumours has taken several routes, leading to extant nodules differing in mode of infection, structure and physiology. Evolution towards optimisation of oxygen usage is continuing.Nitrogen-fixing symbiosis in animal systems is only advantageous in specialised ecological niches in which wood is the sole dietary intake. In the case of shipworms, the symbiosis has many of the advanced features associated with nitrogen fixing root nodules.
20
Markham, John H. "Does Dryas integrifolia fix nitrogen?" Botany 87, no. 11 (November 2009): 1106–9. http://dx.doi.org/10.1139/b09-071.
Abstract:
Symbiotic nitrogen fixation is found in plant taxa that also include non-nitrogen-fixing members. Strong evidence for the occurrence of nitrogen fixation comes from physiological measurements and the identification of the nitrogen fixing symbiont. This evidence has been provided for Dryas drummondii Richardson ex Hook. in the Rosaceae. However, while there have been numerous references to the nitrogen fixing ability of Dryas integrifolia Vahl., they can all be traced to a single report that did not provide strong evidence for nitrogen fixation. My attempts to establish nitrogen fixing nodules on vegetatively propagated plants from the field, or seedlings of D. integrifolia, using three different sources of Frankia , all failed. Since other host plants ( Alnus viridis (Chaix) DC. subsp. crispa (Aiton) Turrill and Purshia tridentata (Pursh.) DC.) did produce nitrogen-fixing nodules under the same growth conditions, the ability of D. integrifolia to fix nitrogen should be considered suspect.
21
Anggrainy, Eka Dewi, Arifah Hidayati, Roby Ibnu Syarifain, Muhammad Faizal Rezha Zulkarnain, and Tualar Simarmata. "Superior Nitrogen Fixing Bacteria Screening from Various Rhizobiome in Palm Oil Plantion, North Sangatta, East Kalimantan." IOP Conference Series: Earth and Environmental Science 748, no. 1 (April 1, 2021): 012007. http://dx.doi.org/10.1088/1755-1315/748/1/012007.
Abstract:
Abstract Nitrogen fixing bacteria (NFB) plays an important role in increasing N availability for plants. Research to examine the ability of nitrogen fixing bacteria isolates to produce nitrogenase, phytohormone and the ability of nitrogen fixing bacteria isolates in the biological test process using the corn plant indicator as an indicator has been carried out from September 2018 to February 2019 in laboratories and greenhouses. The ability of nitrogen fixing bacteria was tested by the ARA method, while the phytohormone testing of nitrogen fixing bacteria was tested using the HPLC method. Bioassays using Murphy media and corn plants as indicators were performed using a randomized block design consisting of six treatments (one control and five selected NFB isolates from the selection results) and given five replications. Measurement of root length, plant height, and dry weight of plants were carried out every 2 days for 14 days. The results showed that the nitrogen fixing bacteria isolates used from North Sangattarhizobiome, East Kalimantan had different nitrogenase and differentphytohormone test results, and obtained five selected isolates based on the selection results. The results of the bioassay did not show any significant differences based on the Duncan test at the level of 5%. However, it can be seen visually the significant difference in which plants in the biological test using nitrogen fixing bacterial isolates have relatively higher plant growth and dry weight of plants than plants that are not given treatment or control.
22
Ekowati, Cristina Nugroho, Mica Mirani, Kusuma Handayani, and Rochmah Agustrina. "DETECTION OF NITROGENASE PRODUCING BACTERIA FROM THE SOIL OF LIWA BOTANICAL GARDEN." Jurnal Ilmiah Biologi Eksperimen dan Keanekaragaman Hayati (J-BEKH) 8, no. 2 (December 30, 2021): 53–58. http://dx.doi.org/10.23960/jbekh.v8i2.204.
Abstract:
Liwa Botanical Gardens is an ex-situ conservation area for various types of plants. Each plant produces organic matter that will provide nutrients for the growth of nitrogen-fixing bacteria. This indicates the existence of an environment that supports the growth of nitrogen-fixing bacteria. Nitrogen is one of the nutrients needed by plants for their growth. However, the abundance of nitrogen in the atmosphere cannot be utilized directly by plants but needs to transform into ammonium and nitrate first. This transformation can be done by nitrogen-fixing bacteria through an enzymatic process. This research aims to obtain bacterial isolates that can fix nitrogen. Nitrogen-fixing bacteria were isolated using Nutrient Agar (NA) medium and furthered by nitrogenase activity detection test with semi-solid Nitrogen Free Bromothymol Blue (NFB). Nitrogen-fixing bacteria are characterized by color changes in the medium. The results obtained 22 isolates with 3 isolates detected capable of producing nitrogenase enzymes, namely TBP B3, TB1 B2, and TMA2 B2.
23
Kirova, E., D. Nedeva, A. Nikolova, and G. Ignatov. "Changes in the electrophoretic spectra of antioxidant enzymes in nitrate-fed and nitrogen-fixing soybean subjected to gradual water stress." Acta Agronomica Hungarica 52, no. 4 (March 1, 2005): 323–32. http://dx.doi.org/10.1556/aagr.52.2004.4.1.
Abstract:
The effect of two sources of nitrogen (nitrogen fixation or nitrate assimilation) and gradual water stress on theelectrophoretic spectra of peroxidase, catalase and superoxide dismutase was studied in soybean leaves. An increase in H2O2 production was observed, especially after the prolonged drought treatment. At 50% drought the activity of anionic peroxidase activity for isoenzymes Nos. 2 and 7+8 significantly increased (by 54 and 18%, respectively) in the leaves of nitrate-fed plants compared to the control plants; for nitrogen-fixing plants these values were 31 and 14%, respectively. In the case of cationic peroxidases, the application of 50% drought led to the inhibition of the moderately fast isoenzymes (Nos. 2 and 3, with Rm 0.5 and 0.65, respectively) and the activation of the fastest moving isoenzyme (No. 4, with Rm 0.8) in nitrate-fed soybean. The same tendency was observed in the leaves of nitrogen-fixing plants. The effect of restricted soil humidity on SOD activity was expressed as a change in the activity of some of the isoenzymes. There was a clear tendency for the SOD isoenzyme activity to increase after the exposure of nitrate-fed and nitrogen-fixing soybean plants to 50% drought treatment. high catalase activity was registered in control nitrate-fed plants. Generally the catalase isoenzyme activity in control nitrogen-fixing plants had low values. Both intensities of water stress (30 and 50% drought) caused an increase in the catalase activity, and this increase was much higher for nitrogen-fixing plants. Therefore, soybean plants responded to drought treatment by changes in the antioxidant enzyme activity, as these changes were partially dependent on the source of nitrogen. The results suggested that nitrogen-fixing soybean plants were more resistant to gradual water stress.
24
Sa, T‐M, and D. W. Israel. "Nitrogen Assimilation in Nitrogen‐Fixing Soybean Plants during Phosphorus Deficiency." Crop Science 35, no. 3 (May 1995): 814–20. http://dx.doi.org/10.2135/cropsci1995.0011183x003500030030x.
25
Newland, J. A., and T. H. DeLuca. "Influence of fire on native nitrogen-fixing plants and soil nitrogen status in ponderosa pine - Douglas-fir forests in western Montana." Canadian Journal of Forest Research 30, no. 2 (February 15, 2000): 274–82. http://dx.doi.org/10.1139/x99-206.
Abstract:
Nitrogen fixing plants have been reported to play an important role in replacing N lost from soil in fire dominated ecosystems. Exclusion of fire from ponderosa pine (Pinus ponderosa Dougl. ex Laws.) - Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests of western Montana has lead to widespread changes in forest structure, composition, and function including a potential reduction in the occurrence of N-fixing plant species. We investigated the effect of fire exclusion and reintroduction of fire on the frequency, occurrence, and function of native N-fixing plant species at 11 paired burned and unburned sites in western Montana. These pairs had been either undisturbed since the early 1900s or had been repeatedly opened by logging and (or) fire over the last 80-100 years. Although the percent cover of N-fixing plants was low at all sites, the cover and frequency of N-fixing plants were significantly greater in sites exposed to fire than in the unburned sites and greater in repeatedly opened sites than in undisturbed sites. In contrast, levels of available N were significantly lower in burned sites compared with unburned sites and in repeatedly opened sites. Nitrogen-fixing plants may have played an important role in maintaining productivity in frequently burned ponderosa pine forests but now appear to be suppressed in fire-excluded forests.
26
Chen, Haoran, and John Markham. "The Interactive Effect of Elevated CO2 and Herbivores on the Nitrogen-Fixing Plant Alnus incana ssp. rugosa." Plants 10, no. 3 (February 26, 2021): 440. http://dx.doi.org/10.3390/plants10030440.
Abstract:
Many studies have found that future predicted CO2 levels can increase plant mass but dilute N content in leaves, impacting antiherbivore compounds. Nitrogen-fixing plants may balance their leaf C:N ratio under elevated CO2, counteracting this dilution effect. However, we know little of how plants respond to herbivores at the higher CO2 levels that occurred when nitrogen-fixing plants first evolved. We grew Alnus incana ssp. rugosa was grown at 400, 800, or 1600 ppm CO2 in soil collected from the field, inoculated with Frankia and exposed to herbivores (Orgyia leucostigma). Elevated CO2 increased nodulated plant biomass and stimulated the nitrogen fixation rate in the early growth stage. However, nitrogen-fixing plants were not able to balance their C:N ratio under elevated CO2 after growing for 19 weeks. When plants were grown at 400 and 1600 ppm CO2, herbivores preferred to feed on leaves of nodulated plants. At 800 ppm CO2, nodulated plants accumulated more total phenolic compounds in response to herbivore damage than plants in the non-Frankia and non-herbivore treatments. Our results suggest that plant leaf defence, not leaf nutritional content, is the dominant driver of herbivory and nitrogen-fixing plants have limited ability to balance C:N ratios at elevated CO2 in natural soil.
27
Gunawan, Agung, Yusminah Hala, Alimuddin Ali, Oslan Jumadi, and Muhammad Junda. "Vegetative growth response of upland rice to Actinomycetes, Azospirillum and Azotobacter." IOP Conference Series: Earth and Environmental Science 911, no. 1 (November 1, 2021): 012060. http://dx.doi.org/10.1088/1755-1315/911/1/012060.
Abstract:
Abstract The research aims is to determine the suitability of nitrogen fixing bacteria, namely Actinomycetes, Azospirillum and Azotobacter with upland rice seeds to the speed of radicle formation and growth of upland rice plants. Upland rice plant growth measurement parameters include; speed of formation of radicle length, upland rice plant height, number of upland rice tillers, dry weight of the top of upland rice plants and roots of upland rice plants, wet weight of upland rice plants and roots of upland rice plants, and total N of upland rice plants and upland roots Testing the application of N2 fixing bacteria on upland rice plants on a laboratory scale was carried out to determine the suitability of microbes with upland rice plant seeds in vitro. The pot test was carried out to determine the suitability of the N2 fixing bacteria with the vegetative growth of upland rice plants in vivo. Data were analyzed using ANOVA with Duncan’s advanced test. The results showed that upland rice plants inoculated with Actinomycetes, Azospirillum and Azotobacter showed significantly different growth from upland rice plants without nitrogen fixing bacteria treatment, namely the radicle formation speed and radicle length, plant height, number of tillers, wet weight, dry weight, and total N (%) plants. It can be concluded that the inoculation of nitrogen-fixing bacteria on upland rice plants has a significant effect on plant vegetative growth parameters and plant nitrogen content.
28
Fallo, Gergonius, Anastasia Buak, and Lukas Pardosi. "SELEKSI Seleksi Dan Identifikasi Bakteri Penambat Nitrogen Pada Perakaran Tanaman Kacang Hijau (Vigna radiata L) Dan Tomat (Solanum lycopersicum L) Di Kabupaten Belu." Jurnal Biologi dan Pembelajarannya (JB&P) 9, no. 1 (April 22, 2022): 34–41. http://dx.doi.org/10.29407/jbp.v9i1.17751.
Abstract:
Nitrogen fixing bacteria are often called diazotroph bacteria which are able to use air nitrogen as a nitrogen source for their growth. Nitrogen fixing bacteria have the ability to increase the efficiency of N- available in the soil. The purpose of this study was to determine the morphological and biochemical characters of nitrogen-fixing bacteria from the roots of mung bean and tomato plants in Belu Regency. Isolation of nitrogen fixing bacteria by scratch method and spread on NA media. While the selection of nitrogen fixing bacteria using Jensen agar media. The results of the isolation obtained 12 isolates. Six isolates from roots of tomato plants and six isolates from roots of mung bean plants. The morphological characters of the 12 isolates were generally round in shape, small in size, flat in elevation and milky white in color. The selection results showed that 3 isolates grew on Jansen agar media, namely RKHB05, RKHB06, and RTB06. The result of gram staining showed that RKHB05, RKHB06 isolates were gram negative and had cocci cell form, while RTB06 isolates were gram positive with bacillus cell forms. The 3 isolates were positive for motility test, Citrate test, TSIA, and Catalase test
29
Rahmani, Tara Puri Ducha. "Simple Feasibility Analysis Of Nitrogen-Fixing Cereals Project." Al-Hayat: Journal of Biology and Applied Biology 3, no. 2 (December 8, 2020): 102. http://dx.doi.org/10.21580/ah.v3i2.6082.
Abstract:
<p>Nitrogen does not directly have advantages in human physiology system, but it holds one of the most critical roles in plants’ life cycle and productivity. Even though Nitrogen is the most abundant elements in the atmosphere, it is also the most deficient essential nutrients in plants. The proposed idea of the nitrogen-fixing GM crops, particularly wheat, is aimed to overcome those stated cons of the traditional diculture and nitrogen fertilizer. This analysis focus on the overview as well as the pro and cons of the genetically modified nitrogen-fixing plants in providing a better agricultural method. The genetically modifying method to generate a nitrogen-fixing non-legumes carries a significant chance of failure results and hindrance. The multilevel implication occurs when we need to modify the plants that not normally produce nodules in their roots to form the nodules and to modify the Nitrogen-fixing microbes to live in the nodules of non-legumes, which are not their natural dwelling places.</p><p>In conclusion, the genetically modified crops project to fix their Nitrogen is feasible, but the difficulties and the funds needed still outweigh the benefits obtained in the future. With all of those limitations, the target goal to erase famine in 2050 just by funding the nitrogen-fixing wheat alone seems to be too high to be reached. The funds and efforts should be better spent on other factors and farming methods.</p>
30
Mohr, Wiebke, Nadine Lehnen, Soeren Ahmerkamp, Hannah K. Marchant, Jon S. Graf, Bernhard Tschitschko, Pelin Yilmaz, et al. "Terrestrial-type nitrogen-fixing symbiosis between seagrass and a marine bacterium." Nature 600, no. 7887 (November 3, 2021): 105–9. http://dx.doi.org/10.1038/s41586-021-04063-4.
Abstract:
AbstractSymbiotic N2-fixing microorganisms have a crucial role in the assimilation of nitrogen by eukaryotes in nitrogen-limited environments1–3. Particularly among land plants, N2-fixing symbionts occur in a variety of distantly related plant lineages and often involve an intimate association between host and symbiont2,4. Descriptions of such intimate symbioses are lacking for seagrasses, which evolved around 100 million years ago from terrestrial flowering plants that migrated back to the sea5. Here we describe an N2-fixing symbiont, ‘Candidatus Celerinatantimonas neptuna’, that lives inside seagrass root tissue, where it provides ammonia and amino acids to its host in exchange for sugars. As such, this symbiosis is reminiscent of terrestrial N2-fixing plant symbioses. The symbiosis between Ca. C. neptuna and its host Posidonia oceanica enables highly productive seagrass meadows to thrive in the nitrogen-limited Mediterranean Sea. Relatives of Ca. C. neptuna occur worldwide in coastal ecosystems, in which they may form similar symbioses with other seagrasses and saltmarsh plants. Just like N2-fixing microorganisms might have aided the colonization of nitrogen-poor soils by early land plants6, the ancestors of Ca. C. neptuna and its relatives probably enabled flowering plants to invade nitrogen-poor marine habitats, where they formed extremely efficient blue carbon ecosystems7.
31
Mahmud, Kishan, Shiva Makaju, Razi Ibrahim, and Ali Missaoui. "Current Progress in Nitrogen Fixing Plants and Microbiome Research." Plants 9, no. 1 (January 13, 2020): 97. http://dx.doi.org/10.3390/plants9010097.
Abstract:
In agroecosystems, nitrogen is one of the major nutrients limiting plant growth. To meet the increased nitrogen demand in agriculture, synthetic fertilizers have been used extensively in the latter part of the twentieth century, which have led to environmental challenges such as nitrate pollution. Biological nitrogen fixation (BNF) in plants is an essential mechanism for sustainable agricultural production and healthy ecosystem functioning. BNF by legumes and associative, endosymbiotic, and endophytic nitrogen fixation in non-legumes play major roles in reducing the use of synthetic nitrogen fertilizer in agriculture, increased plant nutrient content, and soil health reclamation. This review discusses the process of nitrogen-fixation in plants, nodule formation, the genes involved in plant-rhizobia interaction, and nitrogen-fixing legume and non-legume plants. This review also elaborates on current research efforts involved in transferring nitrogen-fixing mechanisms from legumes to non-legumes, especially to economically important crops such as rice, maize, and wheat at the molecular level and relevant other techniques involving the manipulation of soil microbiome for plant benefits in the non-legume root environment.
32
Minamisawa, Kiwamu, Kiyo Nishioka, Taro Miyaki, Bin Ye, Takuya Miyamoto, Mu You, Asami Saito, et al. "Anaerobic Nitrogen-Fixing Consortia Consisting of Clostridia Isolated from Gramineous Plants." Applied and Environmental Microbiology 70, no. 5 (May 2004): 3096–102. http://dx.doi.org/10.1128/aem.70.5.3096-3102.2004.
Abstract:
ABSTRACT We report here the existence of anaerobic nitrogen-fixing consortia (ANFICOs) consisting of N2-fixing clostridia and diverse nondiazotrophic bacteria in nonleguminous plants; we found these ANFICOs while attempting to overcome a problem with culturing nitrogen-fixing microbes from various gramineous plants. A major feature of ANFICOs is that N2 fixation by the anaerobic clostridia is supported by the elimination of oxygen by the accompanying bacteria in the culture. In a few ANFICOs, nondiazotrophic bacteria specifically induced nitrogen fixation of the clostridia in culture. ANFICOs are widespread in wild rice species and pioneer plants, which are able to grow in unfavorable locations. These results indicate that clostridia are naturally occurring endophytes in gramineous plants and that clostridial N2 fixation arises in association with nondiazotrophic endophytes.
33
Kirova, E., D. Nedeva, A. Nikolova, and G. Ignatov. "Changes in the biomass production and total soluble protein spectra of nitrate-fed and nitrogen-fixing soybeans subjected to gradual water stress." Plant, Soil and Environment 51, No. 5 (November 19, 2011): 237–42. http://dx.doi.org/10.17221/3580-pse.
Abstract:
The effect of the sources of nitrogen nutrition (nitrogen fixation or nitrate assimilation) and a gradual water stress on the relative water content, total fresh and dry biomass production, leaf growth, and changes in the total soluble protein spectra were studied. The plants were cultivated as soil cultures in a naturally illuminated greenhouse. Comparative studies were carried out with respect to well-watered, control plants. Nitrogen-fixing control and drought plants had relatively smaller root development but better relative water content and large leaf area on the last sampling day than nitrate-fed soybean plants. Water deficit effects on plant biomass at the end of the period studied (21 days) were independent on the nitrogen source. There was no qualitative difference in the total soluble protein spectra of nitratefed and nitrogen-fixing soybean leaves neither with the progress of development nor under drought conditions. But there was a difference in response to drought in termostable proteins of nitrate-fed and nitrogen-fixing plants. The quantity of termostable proteins in inoculated control plants was lower in some degree compared to uninoculated ones. In inoculated plants the water stress caused an increase in the amount of soluble termostable proteins
34
Dawson, Jeffrey O. "Actinorhizal Plants: Their Use in Forestry and Agriculture." Outlook on Agriculture 15, no. 4 (December 1986): 202–8. http://dx.doi.org/10.1177/003072708601500406.
Abstract:
The increasing cost of synthetic fertilizers has stimulated interest in the nitrogen-fixing property of Rhizobium, particularly as genetic engineering techniques raise the possibility of a symbiotic relationship with cereals. By contrast, the similar root nodules formed by nitrogen-fixing actinomycetes of the genus Frankia have been relatively little studied. Yet, as this article shows, the actinorhizal plants have very considerable possibilities for the utilization of marginal lands, especially in developing countries.
35
Markham, John H., and Corinthe Zekveld. "Nitrogen fixation makes biomass allocation to roots independent of soil nitrogen supply." Canadian Journal of Botany 85, no. 9 (September 2007): 787–93. http://dx.doi.org/10.1139/b07-075.
Abstract:
Biomass allocation patterns in plants are known to be affected by soil nitrogen availability. Since nitrogen availability can depress symbiotic nitrogen fixation, and nitrogen fixation can make plant growth independent of soil nitrogen availability but is energetically costly, it is unclear how allocation patterns in nitrogen-fixing species should respond to variation in soil nitrogen availability. We examined the effect of nitrogen source and concentration on the growth and allocation patterns in the nitrogen-fixing shrub Alnus viridis subsp. crispa (Aiton) Turrill. Plants were grown with either NH4+-N or NO3–-N at a range of low N concentrations, from 0 to 2 mmol·L–1, and either inoculated with Frankia or not. Plants without nodules had 25.l% lower biomass and had double the allocation to roots at all but the 2 mmol·L–1 nitrogen concentration. Even though nodulated plants increased growth with nitrogen concentration, allocation to roots as a fraction of total biomass did not vary in these plants, suggesting increased growth resulted from more efficient nitrogen acquisition. Allocation to roots was a significant predictor of plant growth in non-nodulated plants (r2 = 0.318, for linear least squares fit with log mass) but not for nodulated plants (r2 = 0.108). As nitrogen concentrations increased, allocation to nodules, specific nodule numbers, and the proportion of nitrogen fixed by the plants decreased, demonstrating a shift to soil nitrogen use.
36
Nadkernychna, O. V., and E. P. Kopylov. "NITROGEN FIXING BACTERIA OF SPRING WHEAT ROOT ZONE." Agriciltural microbiology 17 (October 1, 2013): 7–20. http://dx.doi.org/10.35868/1997-3004.17.7-20.
Abstract:
The paper presents the study of active nitrogen fixation bacteria of genera Azotobacter, Azospirillum, Bacillus, Flavobacterium, Enterobacter and Pseudomonas isolated from root zone of spring wheat plants. The ability of selected diazotrophs to form associative systems with spring wheat was investigated. The most significant increase of molecular nitrogen fixation activity in root zone of plants was observed under the Azospirillum species background.
37
Asrul, Asrul, and I. Nyoman Pugeg Aryantha. "ISOLASI DAN IDENTIFIKASI BAKTERI PENAMBAT NITROGEN UNTUK PEMBUATAN BIOFERTILIZER." VIABEL: Jurnal Ilmiah Ilmu-Ilmu Pertanian 15, no. 1 (May 6, 2021): 16–23. http://dx.doi.org/10.35457/viabel.v15i1.1386.
Abstract:
Nitrogen is a macro nutrient needed by plants. Generally, people use inorganic fertilizers to fulfill nitrogen nutrients in plants. The problem then is, the continuous use of synthetic nitrogen fertilizers has a direct negative impact on the soil and a derivative impact on human health. The use of microorganisms, in this case bacteria, to provide nitrogen to plants can be done by isolating it and making it a biological fertilizer agent. Nitrogen fixing bacteria was isolated on the land of the oil palm plantation of PT Astra Agro Lestari. The isolated nitrogen-fixing bacteria were then tested quantitatively for their ability to fix nitrogen. The bacteria with the highest nitrogen fixing ability were then identified by sequencing their DNA nucleotide bases so that the bacterial strains were identified. The result is that there are 13 bacteria that are able to fix nitrogen with the codes J1, J3, Q5, L1, L11, J31, D1, M6, M5, R1, P2, J4 and C7. The quantitative test shows that bacteria with code D1 are the best at fixing nitrogen in the form of NH4, namely 0.27 ppm. The results of D1 bacterial DNA nucleotide base sequencing showed that the putitive Bacillus aerius strain 24K with identical values and query cover reach
38
Daft, M. J., D. M. Clelland, and Isobel C. Gardner. "Symbiosis with endomycorrhizas and nitrogen-fixing organisms." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 85, no. 3-4 (1985): 283–98. http://dx.doi.org/10.1017/s0269727000004073.
Abstract:
SynopsisInteractions amongst plants and different endophytes are prevalent in soils deficient in both nitrogen and phosphorus. Several systems are now recognised, combining infections by both fungi and prokaryotes. Symbiotic associations are ancient and reflect the requirements for the maximum uptake of nitrogen and phosphorus in plant nutrition.
39
Shelp, Barry J., and Robert J. Ireland. "Ureide Metabolism in Leaves of Nitrogen-Fixing Soybean Plants." Plant Physiology 77, no. 3 (March 1, 1985): 779–83. http://dx.doi.org/10.1104/pp.77.3.779.
40
Carpena, Ramón O., Elvira Esteban, M. José Sarro, Jesús Peñalosa, Agustı́n Gárate, Juan J. Lucena, and Pilar Zornoza. "Boron and calcium distribution in nitrogen-fixing pea plants." Plant Science 151, no. 2 (February 2000): 163–70. http://dx.doi.org/10.1016/s0168-9452(99)00210-1.
41
Sprent, J. I., and S. M. de Faria. "Mechanisms of infection of plants by nitrogen fixing organisms." Plant and Soil 110, no. 2 (August 1988): 157–65. http://dx.doi.org/10.1007/bf02226795.
42
Zekveld, Corinthe, and John Markham. "Exposure to aphids increases alder growth and nitrogen fixation." Botany 89, no. 4 (April 2011): 255–61. http://dx.doi.org/10.1139/b11-012.
Abstract:
Plants can respond to herbivore damage by mounting a resistance response or by compensating for lost fitness. Both plant nutrition and interactions with soil microbes can affect these responses. It has been shown that resistance responses can occur before plants have been attacked by herbivores. Here we show that a tolerance type of response can occur when plants are exposed to, but not fed on by, herbivores. Alnus viridis (Chaix) DC. spp. crispa (Ait.) Turrill were grown in sealed containers under positive air pressure with either 0.5 mmol·L–1 or 2.0 mmol·L–1 nitrate and either inoculated or not inoculated with Frankia , their nitrogen-fixing symbiont. Plants were then exposed to the genus-specific aphid Prociphilus tessallatus Fitch, which failed to establish feeding colonies. Exposure to aphids, formation of nitrogen-fixing nodules, and elevated soil nitrogen levels all significantly increased plant yield with no interaction among these factors. A combination of high soil nitrogen, nodulation, and exposure to aphids resulted in the lowest plant root:shoot ratio. Plants that were grown with low nitrogen and were exposed to aphids showed increased nitrogen-fixing activity within a day of being exposed. These results provide further evidence to support the observation that plants can respond to cues from other organisms prior to receiving herbivore damage.
43
Robledo, Marta, Natalia I. García-Tomsig, and José I. Jiménez-Zurdo. "Riboregulation in Nitrogen-Fixing Endosymbiotic Bacteria." Microorganisms 8, no. 3 (March 10, 2020): 384. http://dx.doi.org/10.3390/microorganisms8030384.
Abstract:
Small non-coding RNAs (sRNAs) are ubiquitous components of bacterial adaptive regulatory networks underlying stress responses and chronic intracellular infection of eukaryotic hosts. Thus, sRNA-mediated regulation of gene expression is expected to play a major role in the establishment of mutualistic root nodule endosymbiosis between nitrogen-fixing rhizobia and legume plants. However, knowledge about this level of genetic regulation in this group of plant-interacting bacteria is still rather scarce. Here, we review insights into the rhizobial non-coding transcriptome and sRNA-mediated post-transcriptional regulation of symbiotic relevant traits such as nutrient uptake, cell cycle, quorum sensing, or nodule development. We provide details about the transcriptional control and protein-assisted activity mechanisms of the functionally characterized sRNAs involved in these processes. Finally, we discuss the forthcoming research on riboregulation in legume symbionts.
44
Bai, Lu, Yingming Yang, Ziyue Shi, Yiping Zou, Huixin Zhou, and Jianli Jia. "Improvement of Low-Fertility Soils from a Coal Mining Subsidence Area by Immobilized Nitrogen-Fixing Bacteria." Processes 10, no. 6 (June 14, 2022): 1185. http://dx.doi.org/10.3390/pr10061185.
Abstract:
Coal mining subsidence leads to reductions in soil fertility. In order to improve soil physical and chemical properties and to promote vegetation restoration, a nitrogen-fixing bacterium named S1 was isolated from the coal mining subsidence area in the Shendong mining area, and a zeolite-immobilized nitrogen-fixing bacterium was studied to improve the soil in the subsidence area. The results show that the immobilized nitrogen-fixing bacteria can significantly improve the ammonium nitrogen and nitrate nitrogen of soil by 50 times and 0.6 times, respectively, at 20 days, and it can also improve organic matter. In pot experiments, it was found that immobilized microorganisms can improve germination rate, plant height and the dry and fresh weight of maize. The results of the above soil culture tests and pot experiments were then compared and analyzed. It was found that plants made obvious use of soil ammonium nitrogen and nitrate nitrogen, and planting the plants was conducive to increases in soil organic matter.
45
Puente, Maria-Esther, and Yoav Bashan. "The desert epiphyte Tillandsia recurvata harbours the nitrogen-fixing bacterium Pseudomonas stutzeri." Canadian Journal of Botany 72, no. 3 (March 1, 1994): 406–8. http://dx.doi.org/10.1139/b94-054.
Abstract:
Pseudomonas stutzeri, a nitrogen-fixing bacterium, was isolated from the interior of the desert epiphyte Tillandsia recurvata, which grows on electrical cables and giant columnar cacti in the semiarid zone of Baja California, Mexico. This study is the first to indicate the possible close association between bromeliad plants and nitrogen-fixing bacteria. Key words: beneficial bacteria, bromeliads, Bromeliaceae, nitrogen fixation, Pseudomonas stutzeri, Tillandsia recurvata.
46
Preininger, É., P. Korányi, and I. Gyurján. "IN VITRO METHODS OF CREATING PLANTS CONTAINING NITROGEN FIXING BACTERIA." Acta Horticulturae, no. 447 (October 1997): 603–4. http://dx.doi.org/10.17660/actahortic.1997.447.117.
47
Franche, Claudine, Kristina Lindström, and Claudine Elmerich. "Nitrogen-fixing bacteria associated with leguminous and non-leguminous plants." Plant and Soil 321, no. 1-2 (December 3, 2008): 35–59. http://dx.doi.org/10.1007/s11104-008-9833-8.
48
Hurek, Thomas, Linda L. Handley, Barbara Reinhold-Hurek, and Yves Piché. "Azoarcus Grass Endophytes Contribute Fixed Nitrogen to the Plant in an Unculturable State." Molecular Plant-Microbe Interactions® 15, no. 3 (March 2002): 233–42. http://dx.doi.org/10.1094/mpmi.2002.15.3.233.
Abstract:
The extent to which the N2-fixing bacterial endophyte Azoarcus sp. strain BH72 in the rhizosphere of Kallar grass can provide fixed nitrogen to the plant was assessed by evaluating inoculated plants grown in the greenhouse and uninoculated plants taken from the natural environment. The inoculum consisted of either wild-type bacteria or nifK¯ mutant strain BHNKD4. In N2-deficient conditions, plants inoculated with strain BH72 (N2-fixing test plants) grew better and accumulated more nitrogen with a lower δ15N signature after 8 months than did plants inoculated with the mutant strain (non-N2-fixing control plants). Polyadenylated or polymerase chain reaction-amplified BH72 nifH transcripts were retrieved from test but not from control plants. BH72 nifH transcripts were abundant. The inocula could not be reisolated. These results indicate that Azoarcus sp. BH72 can contribute combined N2 to the plant in an unculturable state. Abundant BH72 nifH transcripts were detected also in uninoculated plants taken from the natural environment, from which Azoarcus sp. BH72 also could not be isolated. Quantification of nitrogenase gene transcription indicated a high potential of strain BH72 for biological N2 fixation in association with roots. Phylogenetic analysis of nitrogenase sequences predicted that uncultured grass endophytes including Azoarcus spp. are ecologically dominant and play an important role in N2-fixation in natural grass ecosystems.
49
Iniguez, A. Leonardo, Yuemei Dong, and Eric W. Triplett. "Nitrogen Fixation in Wheat Provided by Klebsiella pneumoniae 342." Molecular Plant-Microbe Interactions® 17, no. 10 (October 2004): 1078–85. http://dx.doi.org/10.1094/mpmi.2004.17.10.1078.
Abstract:
In this report, all of the criteria necessary for the demonstration of nitrogen fixation in wheat (Triticum aestivum L.), the world's most important crop, are shown upon inoculation with a nitrogen-fixing bacterium, Klebsiella pneumoniae 342 (Kp342). Kp342 relieved nitrogen (N) deficiency symptoms and increased total N and N concentration in the plant. Nitrogen fixation was confirmed by 15N isotope dilution in the plant tissue and in a plant product, chlorophyll. All of these observations were in contrast to uninoculated plants, plants inoculated with a nitrogen-fixing mutant of Kp342, and plants inoculated with dead Kp342 cells. Nitrogenase reductase was produced by Kp342 in the intercellular space of the root cortex. Wild-type Kp342 and the nifH mutant colonized the interior of wheat roots in equal numbers on a fresh weight basis. The nitrogen fixation phenotype described here was specific to cv. Trenton. Inoculation of cvs. Russ or Stoa with Kp342 resulted in no relief of nitrogen deficiency symptoms.
50
Fernandez, George C. J., and J. Creighton Miller. "Interaction Between Rhizobial Inoculation and Fertilizer Nitrogen in Five Cowpea Cultivars." HortScience 21, no. 6 (December 1986): 1345–48. http://dx.doi.org/10.21273/hortsci.21.6.1345.
Abstract:
Abstract Rhizobial inoculation with commercial cowpea ‘EL’ mixed strain inoculant as compared to noninoculation, and effects of four levels (0, 14, 28, and 84 kg·ha−1) of fertilizer N (CaNO3–15.5% N) on yield and N2 fixation components in cowpea [Vigna unguiculata (L.) Walp.] were investigated in a field study. Plants were grown on a vertic albaqualf, fine, montmorillonitic, thermal soil with a pH of 6.7. Three high (H) and two low (L) N2-fixing, indeterminate cowpea cultivars, ‘H-California Blackeye No. 5’, ‘H-Brown Crowder’, ‘H-Tennessee White Crowder’, ‘L-Lady’, and ‘L-Mississippi Silver’, were used. In inoculated plants, N2 fixation was significantly reduced with increasing N levels. Although high-fixing cultivars produced more and larger nodules and expressed higher nitrogenase activity than the low fixers, no significant differences in top dry weight and total N/plant were observed between these groups at the time of flowering. Seed yield was greater in rhizobia-inoculated plants than in the noninoculated, fumigated controls. A significant linear increase in seed yield was observed with increasing N levels in the noninoculated, fumigated controls. The addition of fertilizer N to cowpeas inoculated at planting did not increase seed yield. In high-fixing cultivars, N2 fixation did not directly influence seed yield, but increased vegetative matter was produced. Seed and biomass yield were influenced by N2 fixation in low-fixing cultivars.