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Biological nitrogen fixation in grass  [cached]
, Julierme Zimme rBarbosa; Rangel Consalter; , Antonio Carlos Vargas Motta
Evidência : Ciência e Biotecnologia - Interdisciplinar , 2012,
Abstract: Biological nitrogen fixation in grassAbstractNitrogen (N) due to their role in plant metabolism is the nutrient that most limits crop production. It ispresent in large quantities in air, primarily as di-nitrogen, but unfortunately the plants are not able to 8 Evidência, Joa aba v. 12 n. 1, p. 7-18, janeiro/junho 2012directly use the nutrient in that form, requiring it to be fixed in the form of ammonia. In soil, the fixed N isconverted to nitrate by nitrification process (mediated by Nitrossomonas sp. and Nitrobacter sp. bacteria),thus becomes available for plants. The N fixation may occur via atmospheric, biological and industrial, andthe last was and still is a pillar in the construction and maintenance of modern agriculture. The biologicalnitrogen fixation (BNF) provides economic and environmental advantages, being characterized asan important tool in achieving a more sustainable crop production. Plants of the family Fabaceae (legumes)has the efficiency in the process of BNF known and consecrated, however, four more crops produced inthe world (sugar cane, corn, rice and wheat) are of the family Poaceae (grass), and exploitation of BNF inplants of this family is a recent possibility, with relatively low efficiency, however, the optimization ofthese processes can bring significant benefits, since plants of this family are of paramount importance inproducing food, fiber and energy. Based on the above, this review summarizes knowledge regarding theprocess and efficiency of non-nodulating diazotrophs in Poaceae, in order to assess the state of the scienceof BNF this plants family.
Evaluation of Sugarcane Clones with Biological Nitrogen Fixation Endowment  [PDF]
R. Alam,M.Z. Karim,M. Fida Hasan,M.A. Hossain
Asian Journal of Plant Sciences , 2003,
Abstract: The study was conducted with 45 Sugarcane clones grown at zero-N and 120 kg N ha-1 levels in order to evaluate their possible BNF (biological nitrogen fixation) capability under field conditions. Field evaluation led to identification of some clones viz., I 153/94, Co 846, B 34-104 and Isd 28 that demonstrated considerable BNF capability. The yields of these clones at zero-N were 54.30, 61.48, 53.69 and 63.97 t ha-1 but at 120 kg N ha ̄1 it was 59.72, 65.75, 57.15 and 70.59 t ha-1, respectively. The non BNF clones Isd 2/54 and Isd 18 showed poor yield at zero-N (31.38 and 28.17 t ha-1) while at 120 kg N ha-1 it was 54.61 and 61.58 t ha-1. The BNF capable clones performed almost equally well under both zero-N and 120kg N ha-1 as demonstrated through number of tiller (000 ha-1), number of millable cane (000 ha-1) and leaf nitrogen content at 120 and 200 days after plantation (DAP). Under aseptic culture condition, root extract and cane juice from the BNF- endowed clones showed the presence of gram negative bacterium that have been subjected to further studies.
Improvement in Biological Nitrogen Fixation and Yield of Groundnut By the Application of Effective Microorganisms  [PDF]
M. S. Iqbal,G. Jilani
Pakistan Journal of Biological Sciences , 2000,
Abstract: This study was to find out whether the application of Effective Microorganisms (EM) improves biological nitrogen fixation (BNF) and yield in groundnut under rainfed conditions. Treatments in main plots were two varieties; V1= 1CG-2261 V2= 1CGV 86550. It was concluded that yield and BNF were increased by EM, by both ways of application and variety V1 gave better and BNF then V2.
Present status and development on biological nitrogen fixation research in China
Shihua Shen,Yuxiang Jing
Chinese Science Bulletin , 2003, DOI: 10.1007/BF03184206
Abstract: This presentation introduces the advances in biological nitrogen fixation research abroad, in particular, describes the great progress and achievements on its research in China as follows: collection of rhizobial resources and establishment of the largest database ofRhizobium in China, correction and development ofRhizobium taxonomy in international; discovery of a couple ofnif genes, identification and unification of linkage among thenif gene operonsof Klebsiella pneumoniae, finding of regulative mechanism of positive regulationnif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation genenodD3 product inSinorhizobium meliloti which is not controlled by flavonoid produced from its host alfalfa; finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulation factor ofSinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on the research of gene expression and regulation; chemical simulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of model compounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research in China in future has been put forward, suggesting that thenif gene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions betweenRhizobium and legume, coupling between carbon and nitrogen metabolisms, nitrogen fixation and photosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.
Gas Exchanges and Biological Nitrogen Fixation in Soybean under Water Restriction  [PDF]
Paula Cerezini, Antonio Eduardo Pípolo, Mariangela Hungria, Marco Antonio Nogueira
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.526419
Abstract: Biological nitrogen fixation (BNF) in soybean is vulnerable to drought; however, there are genotypic variations among soybean cultivars regarding the ability to keep BNF under moderate water restriction. The aim of this study was to evaluate parameters related to gas exchanges and regulation of BNF in soybean genotypes BNF drought-tolerant (R01-581F and R01-416F), or drought-susceptible (CD 215 and BRS 317), submitted to adequate water supply or restriction between 45 and 55 days after emergence. We searched for traits associated with tolerance/susceptibility to drought, which might be useful in the selection of drought-tolerant soybean genotypes. Plant biomass was not affected under water restriction, but the number and dry weight of nodules reduced by 33% and 12%, respectively, in the average of genotypes. Drought-tolerant genotypes were more effective in maintaining gas exchanges under water restriction. Under water restriction, all genotypes increased the concentration of ureides in nodules, but only the susceptible genotypes showed that in leaves. The maintenance of gas exchanges and N metabolism regulation under water restriction in genotype R01-581F suggests that these parameters may be used to characterize soybean genotypes that can be sources of drought tolerance in genetic breeding programs.
Genetic Improvement of Biological Nitrogen Fixation in Common Bean Genotypes (Phaseolus vulgaris L.)
Ahmad Reza Golparvar
Agriculturae Conspectus Scientificus (ACS) , 2012,
Abstract: Fifty common bean genotypes were cultivated in two separately field trials at the research station of Islamic Azad University, Khorasgan Branch during 2008-2009. The experimental design was randomized complete block. Bean seeds were inoculated by Rhizobium legominosarum biovar Phaseoli isolate L-109 in one of the experiments before sowing. The dose of Rhizobium for seed inoculation was 7 miligrams of bacteria for 1 kilogram of seed. The second experiment was control. The second experiment was analyzed in the same way as the first except for biological nitrogen fixation. The results showed definite positive and significant correlation in percentage of nitrogen fixation with some other been characters. Step-wise regression designated that total nitrogen percentage in shoot, number of nodules per plant and biomass yield accounted for 93.8% of variation expect for nitrogen fixation percent. Path analysis indicated that total nitrogen percentage in shoot, number of nodules per plant and biomass yield have direct and positive effect on nitrogen fixation index. Hence, total nitrogen percentage in shoot, number of nodules per plant and biomass yield are promising indirect selection criteria for genetic improvement of nitrogen fixation capability in common bean genotypes.
Evaluation of the biological nitrogen fixation contribution in sugarcane plants originated from seeds and inoculated with nitrogen-fixing endophytes
Canuto, Erineudo de Lima;Oliveira, André Luis Martinez de;Reis, Ver?nica Massena;Baldani, José Ivo;
Brazilian Journal of Microbiology , 2003, DOI: 10.1590/S1517-83822003000500021
Abstract: the inoculation technique with endophytic diazotrophic bacteria in sugarcane has been shown as an alternative practice to plant growth promotion. the aim of this work was to evaluate the biological nitrogen fixation (bnf) contribution by different strains of herbaspirillum seropedicae and gluconacetobacter diazotrophicus in sugarcane plant inoculated from seeds. the seeds were planted in pots filled with non-sterile soil, inoculated with the bacterial strains and grown 10 months outside of the greenhouse. the bnf contribution of the inoculated bacteria varied depending on the plant species used as a control. the highest bnf contribution as well as the highest populations of reisolated bacteria was observed with inoculation of h. seropedicae strains. the roots appeared to be the preferential tissues for the establishment of the inoculated species.
Present status and development on biological nitrogen fixation research in China
Shen Shihua,JING Yuxiang,
SHENShihua
,JINGYuxiang

科学通报(英文版) , 2003,
Abstract: This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in China as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inChina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inChina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.
Indirect Selection for Genetic Improvement of Seed Yield and Biological Nitrogen Fixation in Iranian Common Bean Genotypes (Phaseolus vulgaris L.)  [PDF]
Ahmad Reza Golparvar,Abdollah Ghasemi-Pirbalouti
Pakistan Journal of Biological Sciences , 2006,
Abstract: Common bean is one of the most important crops in majority regions of Iran. Determination of effective traits on biological nitrogen fixation and seed yield as indirect selection criteria is very important in breeding this valuable crop. For this reason 160 common bean genotypes were cultivated in two separate augmented design. Genotypes were inoculated with bacteria Rhizobium legominosarum biovar Phaseoli isolate L-109 only in one of the experiments. Second experiment was considered as check for first. Analysis of variance indicated non-significant difference between blocks for all the traits. Correlation analysis showed that majority of the traits had positive and highly significant correlation with percent of nitrogen fixation. Step-wise regression designated that traits percent of total nitrogen of shoot, number of nodule per plant and biological yield accounted for 91.6% of variation in percent of nitrogen fixation. Path analysis indicated that these traits have direct and positive effect on percent of nitrogen fixation. Hence, these traits are promising indirect selection criteria for genetic improvement of nitrogen fixation capability in common bean genotypes. Results of correlation analysis also revealed that all the traits studied correlated positively and significantly with seed yield. Amongst, traits harvest index, biological yield, number of nodule per plant and percent of nitrogen fixation entered to regression model and verified 95% of seed yield variation. Path analysis indicated that harvest index and biological yield have considerable and positive direct effect on seed yield. Therefore, these traits recommend as the best indirect selection criteria for improvement of seed yield especially in early generations.
Multivariate analysis and determination of the best indirect selection criteria to genetic improvement the biological nitrogen fixation ability in common bean genotypes (Phaseolus vulgaris L.)  [PDF]
Golparvar Reza Ahmad
Genetika , 2012, DOI: 10.2298/gensr1202279g
Abstract: In order to determine the best indirect selection criteria for genetic improvement of biological nitrogen fixation, sixty four common bean genotypes were cultivated in two randomized complete block design. Genotypes were inoculated with bacteria Rhizobium legominosarum biovar Phaseoli isolate L-109 only in one of the experiments. The second experiment was considered as check for the first. Correlation analysis showed positive and highly significant correlation of majority of the traits with percent of nitrogen fixation. Step-wise regression designated that traits percent of total nitrogen of shoot, number of nodule per plant and biological yield accounted for 92.3 percent of variation exist in percent of nitrogen fixation. Path analysis indicated that these traits have direct and positive effect on percent of nitrogen fixation. Hence, these traits are promising indirect selection criteria for genetic improvement of nitrogen fixation capability in common bean genotypes especially in early generations.
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