Top PDF Database of diazotrophs in global ocean: abundances, biomass and nitrogen fixation rates

Database of diazotrophs in global ocean: abundances, biomass and nitrogen fixation rates

Database of diazotrophs in global ocean: abundances, biomass and nitrogen fixation rates

relative to true regional means. As the current database does not cover some regions such as the coastal upwelling zones, our estimate could be changed substantially if values differ within these biogeographic domains. The log-normal distributions also reveal high variance of the measurements. As indicated by the geometric error range (Tables 6, 7 and 8), high uncertainties of the global estimated mean still exist espe-

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Distribution of known macrozooplankton abundance and biomass in the global ocean

Distribution of known macrozooplankton abundance and biomass in the global ocean

Luo, Y.-W., Doney, S. C., Anderson, L. A., Benavides, M., Berman- Frank, I., Bode, A., Bonnet, S., Boström, K. H., Böttjer, D., Capone, D. G., Carpenter, E. J., Chen, Y. L., Church, M. J., Dore, J. E., Falcón, L. I., Fernández, A., Foster, R. A., Furuya, K., Gómez, F., Gundersen, K., Hynes, A. M., Karl, D. M., Kita- jima, S., Langlois, R. J., LaRoche, J., Letelier, R. M., Marañón, E., McGillicuddy Jr., D. J., Moisander, P. H., Moore, C. M., Mouriño-Carballido, B., Mulholland, M. R., Needoba, J. A., Or- cutt, K. M., Poulton, A. J., Rahav, E., Raimbault, P., Rees, A. P., Riemann, L., Shiozaki, T., Subramaniam, A., Tyrrell, T., Turk- Kubo, K. A., Varela, M., Villareal, T. A., Webb, E. A., White, A. E., Wu, J., and Zehr, J. P.: Database of diazotrophs in global ocean: abundance, biomass and nitrogen fixation rates, Earth Syst. Sci. Data, 4, 47–73, doi:10.5194/essd-4-47-2012, 2012. Madin, L. P., Horgan, E. F., and Steinberg, D. K.: Zooplankton at the
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Sedimentary and mineral dust sources of dissolved iron to the World Ocean

Sedimentary and mineral dust sources of dissolved iron to the World Ocean

Table 3. Global scale fluxes from the New BEC simulation are compared with the simulations with Fe inputs only from the sediments (SedOnly), with iron inputs only from dust (DustOnly), and with the LowFe and HighDesorp simulations (see text for details). The percentage change in flux relative to the New simulation is shown in parentheses. Fluxes listed include primary production (PP in PgC/yr), export production (ExpP sinking POC flux at 103 m in PgC/yr), nitrogen fixation (Nfix in TgN/yr), and water column denitrification (Denitr in TgN/yr). Also shown is the percentage of ocean area where iron is the limiting nutrient for each phytoplankton group (Diat%Fe – diatoms, Diaz%Fe – diazotrophs, and Sp%Fe – small phytoplankton).
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Overlooked runaway feedback in the marine nitrogen cycle: the vicious cycle

Overlooked runaway feedback in the marine nitrogen cycle: the vicious cycle

tion is switched off. (3) IRON is identical to the BASELINE simulation except that it includes a formulation mimick- ing iron stress on diazotrophs and non-fixing phytoplankton. Specifically, phytoplankton and diazotroph growth rates are multiplied by factors of 0.5 and 0.2, respectively, when mod- elled surface PO −3 4 concentrations are lower than observed monthly-mean PO −3 4 values taken from the World Ocean At- las (WOA) (Conkright et al., 2002) (Fig. A1). Without an ex- plicit representation of iron, this is to dynamically mimic the effects of iron limitation in regions such as the high nutrient low chlorophyll (HNLC) regions, where WOA surface inor- ganic nutrients are not completely drawn down. (4) DOM is a simulation that, in addition to the iron limitation formula- tion, includes DON and DOP compartments and allows dia- zotrophs to use DOP as a P source when phosphate concen- trations are lower than 5 µmol P m −3 . To investigate the im- pacts and relative magnitude of feedback processes linking nitrogen fixation and denitrification, which act on timescales much shorter than the several thousand years needed for a global biogeochemistry-circulation model to reach equilib- rium, we start from observed present-state biogeochemical tracer distributions and limit our model integration time to 150 years. As the circulation field and initial conditions are identical in all our simulations, we interpret the relative dif- ferences among model simulations emerging from the dif- ferences in the biogeochemical model formulations. Our ap- proach of considering the first 150 yr of transient solutions started from observed tracer distributions should ensure that locations and intensities of the tentative feedback processes are closely representative to those one would expect to ob- serve in the real ocean if the biogeochemical controls pre- scribed in the respective model configuration were correct. While we cannot rule out that even the most realistic bio- geochemical model will display a long-term drift away from
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PERFIL TAXONÔMICO E FUNCIONAL MICROBIANO EM AMBIENTES AQUÁTICOS

PERFIL TAXONÔMICO E FUNCIONAL MICROBIANO EM AMBIENTES AQUÁTICOS

Tide pools represent unique environments that are susceptible to temperature and salinity variations, desiccation, and hypoxia. No published studies have described the microbial communities in this environment. In this work we performed the first metagenomic study of the tide pool environment, describing the taxonomic and functional characteristics of the microbial community in the Ocean Beach Tide Pool Area (San Diego, CA). Sequencing revealed that the most abundant species were Alteromonas macleodii, Pseudomonas stutzeri, and Glaciecola psychrophila, which belong to Gammaproteobacteria. The most abundant SEED level 1 functional categories were carbohydrates, amino acids and derivatives, and protein metabolism. No species profile pattern was found in the tide pool metagenomes. At SEED level 3 functional classification, the tide pool group (containing 15 of 19 metagenomes) is clearly distinguished, supported by a bootstrap value of 94%. The variables responsible for clustering of the tide pool group are related to stress conditions. Moreover, when the tide pool group was compared with other metagenomes (seawater and freshwater), several genes from the membrane transport, motility and chemotaxis, and stress response categories were more abundant than other groups. However, the functional diversity index was similar among these communities. Sunlight, nutrient starvation, and salinity may be crucial in determining the microbial community structure in this environment, primarily regarding the functional profile, because tide pools are disconnected from the sea for extended periods during low tide, which results in evaporation and altered nutrient recycling. Thus, these environmental stressors could be fundamental in shaping the tide pool community.
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Biofouling of inlet pipes affects water quality in running seawater aquaria and compromises sponge cell proliferation

Biofouling of inlet pipes affects water quality in running seawater aquaria and compromises sponge cell proliferation

et al., 2000; Park & Takeda, 2008), which is reversed following re-feeding (Aldewachi et al., 1975). The direct relationship between nutrient concentration and cell proliferation in sponges must be investigated further, but we have found preliminary evidence that cell proliferation increases with increasing food supply, using bacterial abundance as proxy for food concentrations. Other energetically costly processes, such as reproduction or regeneration, may also cause changes in sponge cell proliferation rates. For the closely related sponge Halisarca dujardini it was found that up to 69.5% of their body volume could consist of reproductive elements (Ereskovsky, 2000) during their reproductive cycle (presumably causing less energy spent in choanocyte turnover) and cell proliferation significantly decreases during regeneration after wound infliction (Alexander et al., 2015). Unfortunately, to the best of our knowledge, there is no available literature on the reproductive cycle of Halisarca caerulea. We randomly found reproductive elements in histological sections, both oocytes and spermatic cysts, throughout both multi-months fieldwork periods, but it appeared they did not alter the choanocyte proliferation rates during experiments. During regeneration, choanocyte proliferation rates of sponge specimens residing in the aquaria fed by the old inlet pipe were reduced (7.0 ± 2.5% in 6 h) within the first hours after wound infliction. However, after 6 days proliferation rates did not differ significantly anymore from those in steady-state tissue (i.e., the ‘normal’ physiological state of these sponges showing limited growth and a high turnover of choanocytes) (12.8 ± 1.0% in 6 h) (Alexander et al., 2015).
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Development of a system emulating the global carbon cycle in Earth system models

Development of a system emulating the global carbon cycle in Earth system models

When looking at the derivation from the reference (observation or reanalysis) data (Fig. 3e–h), the most obvious problem for the basic MIROC-lite model is, as mentioned in Sect. 1, the precipitation, which does not penetrate into the continental interiors. However, this is not used to drive the Sim-CYCLE terrestrial ecosystem model, and thus has little impact on our simulations. As for the Atlantic meridional overturning, the

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Patterns and emerging trends in global ocean health.

Patterns and emerging trends in global ocean health.

Worldwide, Index scores remained largely unchanged from the 2012 assessment, with coun- tries generally showing at most one to two points difference (Fig. 3, Table M in S1 File). This is not surprising, as the overall composite Index scores, especially at very large scales, should not change much from year-to-year unless dramatic negative (such as an environmental disaster) or positive (such as a large-scale conservation effort) changes occur in the system. Further- more, data layers that do not have updated values dampen changes in scores. The countries with the largest change in Index scores were small regions where a relatively large area was set aside within a Marine Protected Area (South Georgia and South Sandwich Islands) or countries where individual goal scores dropped dramatically (e.g., natural products in Cook Islands) due to a large decrease in ornamental fish and shell harvest. Natural products, coastal protection, and species biodiversity were the only three goals with negative year-to-year changes (Fig. 3, Fig. A in S1 File), indicating that efforts to improve sustainable harvest of natural products, protect and restore coastal habitats, and better manage and protect biodiversity are key areas for mitigating losses and halting further declines in ocean health. Although the Index can help identify where changes are occurring, it cannot always explain why they are occurring, beyond flagging which data sources are driving the changes. The underlying causes of changes in those data sources require further investigation. For example, Croatia and Turkey saw large changes in their clean water goal scores (Fig. 3; Table M in S1 File), which the underlying data (http:// www.ohi-science.org) reveal is due to sharp annual changes in marine debris. Whether these changes are due to actual changes in marine debris or to the quality of data reporting remains unknown, although the use of the same data source collected in the same way each year sug- gests the changes are real.
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Assessment Of NPK In Human Male And Female Urine For Its Fertilising Potential In Agriculture

Assessment Of NPK In Human Male And Female Urine For Its Fertilising Potential In Agriculture

discharge into water is reduced by about 60% irrespective of the type of treatment [10]. Pure urine is sterile but there is the likelihood of cross-contamination with the use of urine separating (Ecosan) toilets [28]. According to Jönsson et al. (2000) separated urine contains a greater part of the total nutrients in normal sewage; 80% of N, 55% of P, and 60% of K in just 1.5% of the volume of the sewage. According to Rheiberger (1936), there are comparable levels of creatine, urea and ammonia nitrogens in urine among primates such as man, mangabeys, baboons and chimpanzees. However, he identified sex differences in creatinine nitrogen coefficients of the male mangabeys, baboons and chimpanzees to be higher than those in the female counterparts. In small cases there was reversal of the magnitude seen in the macaques species precluding an assumption as to the validity of the observation. In analysing sex differences in urine with respect to lysine and α - amino nitrogen, the mean excretion of α - amino nitrogen whether ―total,‖ ―free,‖ or ―bound,‖ was higher for females than for males [22]. Thus, it is possible that the higher rate of amino acid excretion observed in females might be correlated with the sexual cycle, although no evidence of this was observed in the case of the four amino acids studied by Thompson and Kirby (1949) when samples from the same subjects were taken at various stages of the menstrual cycle. The influence of sex (gender) on the level of NPK in human urine has received no attention. Therefore, there is a need to study the effect from the Ecological Sanitation (ECOSAN) perspective, especially under local conditions. This is because gender ECOSAN urinals are going to spring up with the advent of industries and ECOSAN concepts, especially in the developing countries. The use of urine in agriculture has been studied in countries such as Sweden, Germany, Switzerland, South Africa, Burkina Faso and Nigeria. In all these studies, the fertilizing ability of human urine was established as being comparable to that of chemical fertilizers, such as 21% N ammonia. However, in Ghana little U
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SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

)n the context of the cohesion policy, solidarity must represent a support for development . For that purpose, solidarity can be seen as a help for self‐help and its success depends a great deal on the capacity and the training of the people to whom the support of making maximum profit out of these addresses to. This support does not mean exclusively financial support, although it is necessary and important but, of all things, it means an exchange of experiences and cooperation, the development of capacity through training, open discussions with the interested factors and last but not least a critic, but a constructive dialogue between the various levels of government: European, national, regional, local. )n other words, a functional labor market should represent a catalyst for the general objective of the European Union – social and economical cohesion – because it has in view the connections with the different markets of the services and of the goods and generates the necessary income for supporting the participation of the individuals, bringing them together, placing them in collaborations. )n this context, the starting points for promoting the inclusion through the activities of social economy have in view: adapting the institutional environment, developing the public‐private partnership, developing the social dialogue between players, investments in the human capital and supporting the exchange of good practices within the European Union.
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DIET of THE BLUE MARLIN (MAKAIRA NIGRICANS, LACEPEDE 1802) (PERCIFORMES: ISTIOPHORIDAE) of THE SOUTHWESTERN EQUATORIAL ATLANTIC OCEAN.

DIET of THE BLUE MARLIN (MAKAIRA NIGRICANS, LACEPEDE 1802) (PERCIFORMES: ISTIOPHORIDAE) of THE SOUTHWESTERN EQUATORIAL ATLANTIC OCEAN.

were caught on longline, and identified after death, according to the FAO identification key, and measured its lower jaw-fork length, as recommended by Graham et al. (2006). The stomachs were removed by opening the abdominal cavity and by severing them from the intestine and the esophagus. They were, then, stored in plastic bags and properly labeled and frozen onboard at a temperature of about twenty degrees below zero, for a period ranging from one to three months, depending on the duration of the cruise. Lower jaw-fork length (LJFL) (cm), local position, date of sampling site was individually recorded. Stomach content was considered as the material retained in a sieve of 1 mm mesh. Preys were identified to the lowest possible taxon, using specialized literature or help from specialists. Zavala-Camin (1981),
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BIOLOGICAL NITROGEN FIXATION AND ITS EFFECTS ON THE PHYSIOLOGICAL POTENTIAL OF COMMON BEAN SEEDS

BIOLOGICAL NITROGEN FIXATION AND ITS EFFECTS ON THE PHYSIOLOGICAL POTENTIAL OF COMMON BEAN SEEDS

The results were considered very similar among varieties, showing consistency and independence from genotypes. Germination percentage and electrical conductivity were similar for all treatments independently of genotype, showing that the results are reproducible in the other varieties. For all other tests, first count of germination, accelerated aging and seedling length data were not significant among treatments for two of three varieties. Those findings are similar to the ones found in literature (ZUCARELI et al., 2011; GOMES-JÚNIOR & SÁ, 2010; KIKUTI et al., 2007; 2006; CRUSCIOL et al., 2003; AMBROSANO et al., 1999) showing no influences of mineral fertilization on seed physiological potential. However, for first count of germination and seed length in ‘BRS Requinte’ variety, and for accelerated aging in ‘BRS Notável’ variety, differences were found. Based on the results obtained, it was observed that control and inoculant treatments were, in general, inferior from standard N fertilization (120 kg.ha -1 ). Similar results were found by Kikuti et al. (2006), Farinelli et al. (2006) and Toledo et al. (2009), who did find positive effects of N fertilization on seed physiological potential of common bean varieties. Additionally, Toledo et al. (2009)
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Nitrogen fixation: structure, function and bioinorganic modeling of the nitrogenases.

Nitrogen fixation: structure, function and bioinorganic modeling of the nitrogenases.

NITROGEN FIXATION: STRUCTURE, FUNCTION AND BIOINORGANIC MODELING OF THE NITROGENASES. Biological nitrogen fixation, catalyzed by nitrogenases, contributes about half of the nitrogen needed to global agriculture. For forty years synthetic chemists and theoreticians have tried to understand and model the structure and function of this important metalloenzyme. Ten years after the first report on the crystal structure of the MoFe protein, scientists still have not been able to synthesize a chemical equivalent of the FeMo cofactor nor the structure knowledge revealed the key to its catalytic activity. This paper with 104 references presents a review of the most relevant advances in chemical nitrogen fixation and their relation with the nitrogenases.
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CO-INOCULATION STUDY OF BRADYRHIZOBIUM JAPONICUM AND ASPERGILLUS NIGER IN SOYBEAN FOR NITROGEN FIXATION

CO-INOCULATION STUDY OF BRADYRHIZOBIUM JAPONICUM AND ASPERGILLUS NIGER IN SOYBEAN FOR NITROGEN FIXATION

considerable increase in shoot and root length as well as shoot and root weight of seedlings in comparison to control (Brar and Lal, 1991; Thakur and Panwar, 1995; Provorov et al., 1998; Sharma, 2001; Anjum et al., 2006; Mansoor, 2007). Chanway et al. (1989) and Yanni (1992) worked with native rhizobial strains and obtained similar kind of results where increase in nodulation and shoot length was observed in field trial as well as in Leonard Jar assembly. Results of present study come in agreement with the observations of Harper et al. (1997) and Ito et al. (2008) that expression of nodulation and increase in shoot is directly related to the Rhizobium inoculum used. In present study, all ten isolates showed increase in shoot length and shoot dry weight over controls. Although, there was no significant difference observed in shoot length between the ten bacterial isolate treatments but a significant difference was observed when compared to respective controls (Table-1). Similar results have been reported by Provorov et al. (1998), Hayat et al. (2008), and Adeghipour et al. (2010).
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Significance of N<sub>2</sub> fixation in dissolved fractions of organic nitrogen

Significance of N<sub>2</sub> fixation in dissolved fractions of organic nitrogen

with a Thermal Cycler Dice Real Time System (TP800; TaKaRa) using primers and TaqMan probes designed by Church et al. (2005); they determined five nifH phylotypes including the cyanobacteria Crocosphaera spp. (termed Group B), an uncultivated phy- lotype termed Group A that was presumed to be a unicellular cyanobacterium, Tri- chodesmium spp., heterocystous cyanobacteria, and g-proteobacteria in the North Pa-

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Comparison of the allocation of phytomass in soybean and bean and its potential role in biological nitrogen fixation

Comparison of the allocation of phytomass in soybean and bean and its potential role in biological nitrogen fixation

A total of eight soybean plants and eight bean plants were harvested on each of these days. The plants were cut at the ground level and taken to the laboratory, where the leaves were detached to determine the leaf area (LA) with a LI-COR electronic leaf area meter (model LI 3100). The leaves and all of the other organs (roots after being properly washed using a coarse mesh sieve, stems, lateral branches, petioles, pods and grains) were then separated, placed in paper bags and oven dried at 70ºC for 24 hours. Subsequently, the material was weighed and mathematical equations (models) were fitted to the data obtained for the soybean leaf area (LA) and to the dry mass of green leaves (GLDM), petioles (PEDM), branches (BDM), stems (SDM), pods (PDV), and roots (RDM) as a function of the plant age (DAE). The correlation coefficients (r) and significance levels (F-test) were determined. From the equations fitted to the TDM (including roots) and LA, the physiological indicators of the growth: instantaneous crop growth rates (CGR) and instantaneous net assimilation rate (NAR) were determined by the following equations:
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Functional analysis of RTX proteins of Sinorhizobium meliloti and role in biological nitrogen fixation symbiosis

Functional analysis of RTX proteins of Sinorhizobium meliloti and role in biological nitrogen fixation symbiosis

arboris and E. medicae. The search for identities at the amino acid level showed that the best homologues were within the Ensifer/Sinorhizobium genus, followed by a protein of Geminococcus roseus (Table IV). The search for conserved motifs identified 12 putative hemolysin-type calcium-binding repeats corresponding to a total of 24 RTX-toxin nonapeptide repeats (Fig. 3). I-tasser server built the 3D model for SMb20079 show in Fig. 4B based on Pseudomonas sp. MIS 38 lipase, Haemophilus influenza Hap adhesin, an E. coli autotransporter hemoglobin protease and the extracellular lipase LipA from Serratia marcescens. According to gene ontology predictions, the molecular function with higher score (0.63 [0.1]) is serine-type endopeptidase and the biological process is proteolysis (0.63) and biological adhesion (0.48). The expression of SMb20079 gene was decreased in the tolC mutant grown in GMS medium (Santos et al., 2010), being the only microarrays data set with reference to this gene.
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Analysis of quality and cost of FeSiMg treatment master alloy vs. cored wire in production of ductile cast iron

Analysis of quality and cost of FeSiMg treatment master alloy vs. cored wire in production of ductile cast iron

The results of studies on the use of FeSi5%Mg magnesium alloy in modern cored wire injection method for production of nodular and vermicular graphite cast irons were described. The injection of Mg cored wire length is a treatment method which can be used to process The injection of Mg cored wire length is a treatment method which can be used to process iron melted in an electric induction furnace. This paper describes the results of using a high-magnesium ferrosilicon alloy in cored wire (Mg recovery 47-70%) for the production of vermicular and nodular graphite cast irons at in at least 13 foundries. The results of calculations and experiments have indicated the length of the cored wire to be injected basing on the initial sulfur content and weight of the treated melt. The results of numerous trials have shown that the magnesium cored wire process can produce high quality nodular and vermicular graphite irons under the specific industrial conditions of the above mentioned foundries. It has also been proved that in the manufacture of nodular graphite iron, the cost of the nodulariser in the form of elastic cored wire is lower than the cost of the FeSiMg5 master alloys.
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Production of bacterial reserve compounds from industrial wastewaters

Production of bacterial reserve compounds from industrial wastewaters

This research project aimed to study the production of reserve compounds such as polyhydroxyalkanoates, triacylglycerols and wax esters using mixed bacterial cultures. This study can be divided in three main parts where some objectives were defined. The first part included the production and optimization at pilot scale of a novel product: biomass enriched in polyhydroxyalkanoates, for application trials. This main goal was accomplished with complete success, with an installation of a complete set-up to produce enriched sludge in PHA at pilot scale. To reach the main goal proposed, many challenges had to be overcome. The first challenge to overcome was to have a mixed bacterial culture enriched with about 40% of PHA, after fermentation. The second challenge to overcome was to stabilize the cells, i.e. to prevent conversion of the intracellular PHA and stored during fermentation. The third challenge to overcome was improving the settling characteristics to get a quick and efficient thickening and drying of the sludge. A last but not least challenge was to determine the most suitable way to store the final product. Besides that, the study went further than what was expected in the beginning. Analytical methods were developed for quantification of the novel product, which were inexistent at Avecom NV.
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Inoculation with Azospirillum, associated with nitrogen fertilization in maize

Inoculation with Azospirillum, associated with nitrogen fertilization in maize

Increased leaf N content, found in this study, may have enhanced the effects of nitrogen in plant development, since the formation of grain in maize culture is closely related to the translocation of sugars (Crawford et al., 1982) and nitrogen (Karlen et al. 1988) of vegetative organs, especially from the leaves, to the grains. Moreover, a higher content of nitrogen in leaves is associated with increased production of pigments and proteins necessary for photosynthesis and photochemical and carboxylate processes performance (Field & Mooney, 1986; Andreeva et al., 1998), increasing the photosynthetically active leaf area of plant directly associated with crop yield.
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