N2-Fixation, nodule efficiency and biomass accumulation after two years in three Chilean legume trees and Tagasaste Chamaecytisus proliferus subsp. palmensis

1996 ◽  
Vol 179 (1) ◽  
pp. 131-140 ◽  
Author(s):  
Carlos Ovalle ◽  
Luis Longeri ◽  
James Aronson ◽  
Alfonzo Herrera ◽  
Julia Avenda�o
Keyword(s):  
N2 Fixation ◽  
Biomass Accumulation ◽  
Legume Trees ◽  
Nodule Efficiency ◽  
Chamaecytisus Proliferus

scholarly journals The Quorum Sensing Auto-Inducer 2 (AI-2) Stimulates Nitrogen Fixation and Favors Ethanol Production over Biomass Accumulation in Zymomonas mobilis

2021 ◽  
Vol 22 (11) ◽  
pp. 5628
Author(s):  
Valquíria Campos Alencar ◽  
Juliana de Fátima dos Santos Silva ◽  
Renata Ozelami Vilas Boas ◽  
Vinícius Manganaro Farnézio ◽  
Yara N. L. F. de Maria ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Quorum Sensing ◽  
Ethanol Production ◽  
N2 Fixation ◽  
Energy Demand ◽  
Zymomonas Mobilis ◽  
Biomass Accumulation ◽  
High Energy ◽  
Gram Negative ◽  
Expression Of Genes

Autoinducer 2 (or AI-2) is one of the molecules used by bacteria to trigger the Quorum Sensing (QS) response, which activates expression of genes involved in a series of alternative mechanisms, when cells reach high population densities (including bioluminescence, motility, biofilm formation, stress resistance, and production of public goods, or pathogenicity factors, among others). Contrary to most autoinducers, AI-2 can induce QS responses in both Gram-negative and Gram-positive bacteria, and has been suggested to constitute a trans-specific system of bacterial communication, capable of affecting even bacteria that cannot produce this autoinducer. In this work, we demonstrate that the ethanologenic Gram-negative bacterium Zymomonas mobilis (a non-AI-2 producer) responds to exogenous AI-2 by modulating expression of genes involved in mechanisms typically associated with QS in other bacteria, such as motility, DNA repair, and nitrogen fixation. Interestingly, the metabolism of AI-2-induced Z. mobilis cells seems to favor ethanol production over biomass accumulation, probably as an adaptation to the high-energy demand of N2 fixation. This opens the possibility of employing AI-2 during the industrial production of second-generation ethanol, as a way to boost N2 fixation by these bacteria, which could reduce costs associated with the use of nitrogen-based fertilizers, without compromising ethanol production in industrial plants.

scholarly journals Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic

2016 ◽  
Vol 13 (3) ◽  
pp. 781-794 ◽  
Author(s):  
J. Meyer ◽  
C. R. Löscher ◽  
S. C. Neulinger ◽  
A. F. Reichel ◽  
A. Loginova ◽  
...  
Keyword(s):  
Organic Matter ◽  
Primary Production ◽  
North Atlantic ◽  
N2 Fixation ◽  
Biomass Accumulation ◽  
Phytoplankton Production ◽  
Nutrient Stoichiometry ◽  
Tropical North Atlantic ◽  
The Impact ◽  
Diazotrophic Community

Abstract. Ocean deoxygenation due to climate change may alter redox-sensitive nutrient cycles in the marine environment. The productive eastern tropical North Atlantic (ETNA) upwelling region may be particularly affected when the relatively moderate oxygen minimum zone (OMZ) deoxygenates further and microbially driven nitrogen (N) loss processes are promoted. Consequently, water masses with a low nitrogen to phosphorus (N : P) ratio could reach the euphotic layer, possibly influencing primary production in those waters. Previous mesocosm studies in the oligotrophic Atlantic Ocean identified nitrate availability as a control of primary production, while a possible co-limitation of nitrate and phosphate could not be ruled out. To better understand the impact of changing N : P ratios on primary production and N2 fixation in the ETNA surface ocean, we conducted land-based mesocosm experiments with natural plankton communities and applied a broad range of N : P ratios (2.67–48). Silicic acid was supplied at 15 µmol L−1 in all mesocosms. We monitored nutrient drawdown, biomass accumulation and nitrogen fixation in response to variable nutrient stoichiometry. Our results confirmed nitrate to be the key factor determining primary production. We found that excess phosphate was channeled through particulate organic matter (POP) into the dissolved organic matter (DOP) pool. In mesocosms with low inorganic phosphate availability, DOP was utilized while N2 fixation increased, suggesting a link between those two processes. Interestingly this observation was most pronounced in mesocosms where nitrate was still available, indicating that bioavailable N does not necessarily suppress N2 fixation. We observed a shift from a mixed cyanobacteria–proteobacteria dominated active diazotrophic community towards a diatom-diazotrophic association of the Richelia-Rhizosolenia symbiosis. We hypothesize that a potential change in nutrient stoichiometry in the ETNA might lead to a general shift within the diazotrophic community, potentially influencing primary productivity and carbon export.

Selection of soybean (Glycine max) lines for increased tolerance of N2 fixation to drying soil

Agronomie ◽  
2001 ◽  
Vol 21 (6-7) ◽  
pp. 653-657 ◽  
Author(s):  
Thomas R. Sinclair ◽  
Larry C. Purcell ◽  
Vincent Vadez ◽  
Rachid Serraj
Keyword(s):  
Glycine Max ◽  
N2 Fixation ◽  
Selection Of

FEATURES OF THE PRODUCTION PROCESS OF ANCIENT AND MODERN VARIETIES OF WINTER RYE

1970 ◽  
pp. 15-19
Author(s):  
A. A. Torop ◽  
V. V. Chaykin ◽  
E. A. Torop ◽  
I. S. Brailova ◽  
S. A. Kuzmenko
Keyword(s):  
Production Process ◽  
Dry Matter ◽  
Leaf Surface ◽  
Unit Area ◽  
Biomass Accumulation ◽  
Vegetation Period ◽  
Winter Rye ◽  
Total Chlorophyll ◽  
Potential Productivity ◽  
Productivity Potential

We compared peculiarities of the production process of the older and modern(created 80 years after) sorts of winter rye. It is determined that the specific coenotic productivity of a modern sort is 60.6% higher.This increase is due to higher number of productive sprouts per unit area and higher sprout weight. The coenosis of modern sorts is highly resistant to lodging. The modern sort has a 33.5% higher leaf surface index and a 17.7% higher share of the leaves in the upper tier, differing in their erectile orientation in space. As for the content of total chlorophyll in the dry matter of leaves and vagina, the modern sort is inferior to the older by 30.2%during theearing period, and by 17.5%during the milky-wax ripeness period.As for the content of total chlorophyll in the sowing area, the compared sorts were practically the same, but the ratio between chlorophyll a and c was noticeably different. As for the chlorophyll content in stems, in dry matter and in the area of ​​sowing, the modern sort is inferior by1.5 times and more to the older in both observation terms. The sorts differed in the biomass accumulation and its distribution between the parts during the vegetation period. To establish the ear productivity, the older sort used only the current photosynthesis products.In conditions of an unfavorable growth year, the modern sort used previously accumulated by leaves and re-utilized assimilates. The actual and potential productivity of an ear in a modern sort is higher by 77.4 and 68.0%, respectively, but the degree of its vegetative mass supply is lower by 48.6%.Only due to the higher, by 77.4%, utilization of the mass of the sprout, the modern sort binds a greater number of grains in the ear with a higherseparate mass.Since the sharp increase in the ear productivity potential was not accompanied by the same growth of the sprout vegetative mass, the modern sort, in unfavorable conditions for growth, has tensions in the relation system between the sprout vegetative mass and pouring grain. This may be the reason of the unstable achievedyield level.

Effect of pre-flowering light deficiency on biomass accumulation and physiological characteristics of rice

2011 ◽  
Vol 19 (2) ◽  
pp. 347-352 ◽  
Author(s):  
Dong YANG ◽  
Liu-Sheng DUAN ◽  
Hua-An XIE ◽  
Zhao-Hu LI ◽  
Ting-Xu HUANG
Keyword(s):  
Biomass Accumulation ◽  
Physiological Characteristics ◽  
Light Deficiency

Identification of Promiscuous Nodulating Soybean Efficient in N2 Fixation 1

Crop Science ◽  
1985 ◽  
Vol 25 (4) ◽  
pp. 660-663 ◽  
Author(s):  
E. L. Pulver ◽  
E. A. Kueneman ◽  
V. Ranga‐Rao
Keyword(s):  
N2 Fixation
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