scholarly journals Environmental Factors Associated With Nitrogen Fixation Prediction in Soybean

2021 ◽  
Vol 12 ◽  
Author(s):  
André Froes de Borja Reis ◽  
Luiz Moro Rosso ◽  
Larry C. Purcell ◽  
Seth Naeve ◽  
Shaun N. Casteel ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Predictive Models ◽  
Seed Protein ◽  
Sowing Date ◽  
Elastic Net ◽  
Sustainable Intensification ◽  
N Fixation ◽  
Small Magnitude ◽  
Factors Associated ◽  
Seed Protein Concentration

Biological nitrogen (N)-fixation is the most important source of N for soybean [Glycine max (L.) Merr.], with considerable implications for sustainable intensification. Therefore, this study aimed to investigate the relevance of environmental factors driving N-fixation and to develop predictive models defining the role of N-fixation for improved productivity and increased seed protein concentration. Using the elastic net regularization of multiple linear regression, we analyzed 40 environmental factors related to weather, soil, and crop management. We selected the most important factors associated with the relative abundance of ureides (RAU) as an indicator of the fraction of N derived from N-fixation. The most relevant RAU predictors were N fertilization, atmospheric vapor pressure deficit (VPD) and precipitation during early reproductive growth (R1–R4 stages), sowing date, drought stress during seed filling (R5–R6), soil cation exchange capacity (CEC), and soil sulfate concentration before sowing. Soybean N-fixation ranged from 60 to 98% across locations and years (n = 95). The predictive model for RAU showed relative mean square error (RRMSE) of 4.5% and an R2 value of 0.69, estimated via cross-validation. In addition, we built similar predictive models of yield and seed protein to assess the association of RAU and these plant traits. The variable RAU was selected as a covariable for the models predicting yield and seed protein, but with a small magnitude relative to the sowing date for yield or soil sulfate for protein. The early-reproductive period VPD affected all independent variables, namely RAU, yield, and seed protein. The elastic net algorithm successfully depicted some otherwise challenging empirical relationships to assess with bivariate associations in observational data. This approach provides inference about environmental variables while predicting N-fixation. The outcomes of this study will provide a foundation for improving the understanding of N-fixation within the context of sustainable intensification of soybean production.

scholarly journals Ozone Induced Loss of Seed Protein Accumulation Is Larger in Soybean than in Wheat and Rice

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 357 ◽  
Author(s):  
Malin Broberg ◽  
Sara Daun ◽  
Håkan Pleijel
Keyword(s):  
Seed Yield ◽  
Protein Concentration ◽  
Seed Protein ◽  
Negative Influence ◽  
Protein Yield ◽  
Protein Accumulation ◽  
N Fixation ◽  
Seed Protein Concentration ◽  
Different Response ◽  
Positive Effect

We investigated the effects of ozone (O3) on seed protein accumulation in soybean, rice, and wheat based on existing literature. We identified 30, 10, and 32 datasets meeting the requirements for soybean, rice, and wheat, respectively. Data for each crop were combined in response regressions for seed protein concentration, seed protein yield, and seed yield. Although seed yield in rice was less sensitive to O3 than in wheat, there was a significant positive effect of O3 on the seed protein concentration of the same magnitude in both crops. Soybean, an N-fixing high-protein crop, responded differently. Even though the effect on seed yield was similar to wheat, there was no indication of any effect of O3 on seed protein concentration in soybean. The negative influence of O3 on seed protein yield was statistically significant for soybean and wheat. The effect was larger for soybean (slope of response function: −0.58% per ppb O3) than for wheat (slope: −0.44% per ppb) and especially compared to rice (slope: −0.08% per ppb). The different response of protein concentration in soybean, likely to be associated with adverse O3 effects on N fixation, has large implications for global protein production because of the much higher absolute protein concentration in soybean.

scholarly journals Increased nitrogen fixation and remobilization may contribute to higher seed protein without a yield penalty in a soybean introgression line

2019 ◽  
Author(s):  
Anna M. Locke ◽  
Martha E. Ramirez
Keyword(s):  
Protein Concentration ◽  
Seed Protein ◽  
Developmental Stages ◽  
Introgression Line ◽  
N Fixation ◽  
Recurrent Parent ◽  
Seed Protein Concentration ◽  
Lower Protein ◽  
N Remobilization ◽  
Yield Penalty

AbstractThe development of soybean varieties with higher seed protein concentration has been hindered by a negative correlation between seed protein concentration and yield. Benning HP, a genotype that breaks this tradeoff, contains a high protein allele introgressed into the cultivar Benning. Because seed protein is thought to be limited by N, field and growth chamber experiments were performed to identify the N flux(es) that enable Benning HP’s increased seed protein without a yield penalty. When the N source was completely controlled in growth chambers, Benning HP was able to fix more N than its recurrent parent, but this response depended on the strain of the rhizobia symbiont and was not observed at all developmental stages. In the field, Benning HP remobilized N from its leaves at a higher rate during seed fill, but this response was only observed in one of the years studied. These results demonstrate that Benning HP has higher potential for N fixation and N remobilization from vegetative tissue compared to its lower protein recurrent parent, but those traits are not consistently expressed and may depend on environmental and sink control.

Mass School Shootings in the United States: A Novel Root Cause Analysis Using Lay Press Reports

2019 ◽  
Vol 58 (13) ◽  
pp. 1423-1428 ◽  
Author(s):  
Chris A. Rees ◽  
Lois K. Lee ◽  
Eric W. Fleegler ◽  
Rebekah Mannix
Keyword(s):  
United States ◽  
Environmental Factors ◽  
Root Cause Analysis ◽  
The United States ◽  
School Shootings ◽  
Contributing Factors ◽  
Mass Shootings ◽  
Cause Analysis ◽  
Factors Associated ◽  
Root Cause

School shootings comprise a small proportion of childhood deaths from firearms; however, these shootings receive a disproportionately large share of media attention. We conducted a root cause analysis of 2 recent school shootings in the United States using lay press reports. We reviewed 1760 and analyzed 282 articles from the 10 most trusted news sources. We identified 356 factors associated with the school shootings. Policy-level factors, including a paucity of adequate legislation controlling firearm purchase and ownership, were the most common contributing factors to school shootings. Mental illness was a commonly cited person-level factor, and access to firearms in the home and availability of large-capacity firearms were commonly cited environmental factors. Novel approaches, including root cause analyses using lay media, can identify factors contributing to mass shootings. The policy, person, and environmental factors associated with these school shootings should be addressed as part of a multipronged effort to prevent future mass shootings.

scholarly journals Risk and Environmental Factors Associated with the Presence of Canine Parvovirus Type 2 in Diarrheic Dogs from Thessaly, Central Greece

Pathogens ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 590
Author(s):  
Maria Kantere ◽  
Labrini V. Athanasiou ◽  
Alexios Giannakopoulos ◽  
Vassilis Skampardonis ◽  
Marina Sofia ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Clinical Symptoms ◽  
Gastrointestinal Disease ◽  
Environmental Parameters ◽  
Canine Parvovirus ◽  
Geographical Information ◽  
Factors Associated ◽  
Working Dogs ◽  
Canine Parvovirus Type 2

Canine parvovirus type 2 (CPV-2) primarily infects dogs, which are the main host reservoir, causing severe gastrointestinal disease associated with immunosuppression. The present study was conducted in Thessaly, Greece and aimed to identify risk and environmental factors associated with CPV-2 infection in diarrheic dogs. Fecal samples were collected from 116 dogs presenting diarrhea and were tested by polymerase chain reaction (PCR) for the presence of CPV-2 DNA. Supplementary data regarding clinical symptoms, individual features, management factors and medical history were also gathered for each animal during clinical evaluation. Sixty-eight diarrheic dogs were found to be positive for the virus DNA in their feces. Statistical analysis revealed that CPV-2 DNA was less likely to be detected in senior dogs, while working dogs, namely hounds and shepherds, had higher odds to be positive for the virus. Livestock density and land uses, specifically the categories of discontinuous urban fabric and of human population density, were identified as significant environmental parameters associated with CPV-2 infection by using Geographical Information System (GIS) together with the Ecological Niche Model (ENM). This is the first description of the environmental variables associated with the presence of CPV-2 DNA in dogs’ feces in Greece.

Environmental Factors Associated with Porcine Adrenal Size and Muscle Characteristics

1965 ◽  
Vol 24 (1) ◽  
pp. 127-130 ◽  
Author(s):  
P. B. Addis ◽  
M. D. Judge ◽  
R. A. Pickett ◽  
H. W. Jones
Keyword(s):  
Environmental Factors ◽  
Factors Associated
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