Synthetic glycolate metabolism pathways stimulate crop growth and productivity in the field

Photorespiration is required in C3 plants to metabolize toxic glycolate formed when ribulose-1,5-bisphosphate carboxylase-oxygenase oxygenates rather than carboxylates ribulose-1,5-bisphosphate. Depending on growing temperatures, photorespiration can reduce yields by 20 to 50% in C3 crops. Inspired by earlier work, we installed into tobacco chloroplasts synthetic glycolate metabolic pathways that are thought to be more efficient than the native pathway. Flux through the synthetic pathways was maximized by inhibiting glycolate export from the chloroplast. The synthetic pathways tested improved photosynthetic quantum yield by 20%. Numerous homozygous transgenic lines increased biomass productivity between 19 and 37% in replicated field trials. These results show that engineering alternative glycolate metabolic pathways into crop chloroplasts while inhibiting glycolate export into the native pathway can drive increases in C3 crop yield under agricultural field conditions.

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Simultaneous Tests and Confidence Intervals for the Evaluation of Agricultural Field Trials

Agronomy Journal ◽

10.2134/agronj2004.1323 ◽

2004 ◽

Vol 96 (5) ◽

pp. 1323-1330 ◽

Cited By ~ 4

Author(s):

Cornelia Frömke ◽

Frank Bretz

Keyword(s):

Confidence Intervals ◽

Field Trials ◽

Agricultural Field

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Retinal Redox Stress and Remodeling in Cardiometabolic Syndrome and Diabetes

Oxidative Medicine and Cellular Longevity ◽

10.4161/oxim.3.6.14786 ◽

2010 ◽

Vol 3 (6) ◽

pp. 392-403 ◽

Cited By ~ 29

Author(s):

Ying Yang ◽

Melvin R. Hayden ◽

Susan Sowers ◽

Sarika V. Bagree ◽

James R. Sowers

Keyword(s):

Metabolic Pathways ◽

Tissue Injury ◽

Disease Process ◽

Polyol Pathway ◽

The United States ◽

Redox Stress ◽

Blood Retinal Barrier ◽

Cardiometabolic Syndrome ◽

Hexosamine Pathway ◽

Pathway Flux

Diabetic retinopathy (DR) is a significant cause of global blindness; a major cause of blindness in the United States in people aged between 20–74. There is emerging evidence that retinopathy is initiated and propagated by multiple metabolic toxicities associated with excess production of reactive oxygen species (ROS). The four traditional metabolic pathways involved in the development of DR include: increased polyol pathway flux, advanced glycation end-product formation, activation of protein kinase Cisoforms and hexosamine pathway flux. These pathways individually and synergisticallycontribute to redox stress with excess ROS resulting in retinal tissue injury resulting in significant microvascular blood retinal barrier remodeling. The toxicity of hyperinsulinemia, hyperglycemia, hypertension, dyslipidemia, increased cytokines and growth factors, in conjunction with redox stress, contribute to the development and progression of DR. Redox stress contributes to the development and progression of abnormalities of endothelial cells and pericytes in DR. This review focuses on the ultrastructural observations of the blood retinal barrier including the relationship between the endothelial cell and pericyte remodeling in young nine week old Zucker obese (fa/ fa) rat model of obesity; cardiometabolic syndrome, and the 20 week old alloxan induced diabetic porcine model. Preventing or delaying the blindness associated with these intersecting abnormal metabolic pathways may be approached through strategies targeted to reduction of tissue inflammation and oxidative—redox stress. Understanding these abnormal metabolic pathways and the accompanying redox stress and remodeling mayprovide both the clinician and researcher a new concept of approaching this complicated disease process

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Evaluation of Harvest-Aid Herbicides as Desiccants in Lentil Production

Weed Technology ◽

10.1614/wt-d-16-00007.1 ◽

2016 ◽

Vol 30 (3) ◽

pp. 629-638 ◽

Cited By ~ 5

Author(s):

Ti Zhang ◽

Eric N. Johnson ◽

Christian J. Willenborg

Keyword(s):

Adverse Effects ◽

Crop Yield ◽

Seed Yield ◽

Yield Loss ◽

Field Trials ◽

Growth Stages ◽

Yield And Quality ◽

Seed Field ◽

Dry Down ◽

General Reduction

Desiccants are currently used to improve lentil dry-down prior to harvest. Applying desiccants at growth stages prior to maturity may result in reduced crop yield and quality, and leave unacceptable herbicide residues in seeds. There is little information on whether various herbicides applied alone or as a tank-mix with glyphosate have an effect on glyphosate residues in harvested seed. Field trials were conducted at Saskatoon and Scott, Saskatchewan, Canada, from 2012 to 2014 to determine whether additional desiccants applied alone or tank mixed with glyphosate improve crop desiccation and reduce the potential for unacceptable glyphosate residue in seed. Glufosinate and diquat tank mixed with glyphosate were the most consistent desiccants, providing optimal crop dry-down and a general reduction in glyphosate seed residues without adverse effects on seed yield and weight. Saflufenacil provided good crop desiccation without yield loss, but failed to reduce glyphosate seed residues consistently. Pyraflufen-ethyl and flumioxazin applied alone or tank mixed with glyphosate were found to be inferior options for growers as they exhibited slow and incomplete crop desiccation, and did not decrease glyphosate seed residues. Based on results from this study, growers should apply glufosinate or diquat with preharvest glyphosate to maximize crop and weed desiccation, and minimize glyphosate seed residues.

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Transcriptome-wide gene expression plasticity in Stipa grandis in response to grazing intensity differences

10.22541/au.160655409.95797246/v1 ◽

2020 ◽

Author(s):

Zhenhua Dang ◽

Yuanyuan Jia ◽

Yunyun Tian ◽

Jiabin Li ◽

Yanan Zhang ◽

...

Keyword(s):

Gene Expression ◽

Metabolic Pathways ◽

Molecular Mechanisms ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Grazing Intensity ◽

Glycolate Oxidase ◽

Bisphosphate Carboxylase ◽

Grazing Intensities

Organisms have evolved effective and distinct adaptive strategies to survive. Stipa grandis is one of the widespread dominant species on the typical steppe of the Inner Mongolian Plateau, and is regarded as a suitable species for studying the effects of grazing in this region. Although phenotypic (morphological and physiological) variations in S. grandis in response to long-term grazing have been identified, the molecular mechanisms underlying adaptations and plastic responses remain largely unknown. Accordingly, we performed a transcriptomic analysis to investigate changes in gene expression of S. grandis under four different grazing intensities. A total of 2,357 differentially expressed genes (DEGs) were identified among the tested grazing intensities, suggesting long-term grazing resulted in gene expression plasticity that affected diverse biological processes and metabolic pathways in S. grandis. DEGs were identified that indicated modulation of Calvin–Benson cycle and photorespiration metabolic pathways. The key gene´expression profiles encoding various proteins (e.g., Ribulose-1,5-bisphosphate carboxylase/oxygenase, fructose-1,6-bisphosphate aldolase, glycolate oxidase etc.) involved in these pathways suggest that they may synergistically respond to grazing to increase the resilience and stress tolerance of S. grandis. Our findings provide scientific clues for improving grassland use and protection, and identify important questions to address in future transcriptome studies.

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Restoring the Soils of Nauru: Plants as Tools for Ecological Recovery

10.26686/wgtn.16992997.v1 ◽

2021 ◽

Author(s):

◽

Alexander Feary

Keyword(s):

Biomass Production ◽

Soil Type ◽

Biomass Productivity ◽

Well Being ◽

Field Trials ◽

Small Degree ◽

Tissue Type ◽

Soil Restoration ◽

Landscape Degradation ◽

Germination Success

<p>The restoration of Nauru’s mined areas is fundamental to the future wellbeing of the people and ecosystems of Nauru. Extensive open cast phosphate mining on Nauru over the last 100 years has led to soil losses and landscape degradation to the extent that over 70% of this South-Western Pacific island state is now uninhabitable and almost all productive land has been lost. Significant landscape degradation has occurred and as a consequence the soils that remain are insufficient in volume and quality to achieve the Government’s restoration goals which support the long-term development of Nauru and the well-being of its people. The aim of this research is to evaluate aspects of cover-crop use as a means for soil restoration in Nauru. This research evaluates biomass production, phytoremediation potential, and germination success for a range of species in Nauruan soils. Field trials exploring biomass production and cadmium phytoextraction were performed, as was an experiment assessing the effects of cadmium on germination success. It was found that, in the circumstances assessed, biomass productivity was significantly determined by species, mulch use, soil type, and to a small degree – cadmium. Phytoextraction was significantly determined by tissue type. Germination success was not determined by soil cadmium, but soil type was a significant factor.</p>

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Glycolate metabolism in cyanobacteria. IV. Uptake, growth and metabolic pathways

Physiologia Plantarum ◽

10.1034/j.1399-3054.1990.780218.x ◽

1990 ◽

Vol 78 (2) ◽

pp. 285-292 ◽

Cited By ~ 1

Author(s):

Eva Renstrom-Kellner ◽

Birgitta Bergman

Keyword(s):

Metabolic Pathways ◽

Glycolate Metabolism

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Flexible modelling of spatial variation in agricultural field trials with the R package INLA

Theoretical and Applied Genetics ◽

10.1007/s00122-019-03424-y ◽

2019 ◽

Vol 132 (12) ◽

pp. 3277-3293 ◽

Cited By ~ 6

Author(s):

Maria Lie Selle ◽

Ingelin Steinsland ◽

John M. Hickey ◽

Gregor Gorjanc

Keyword(s):

Spatial Variation ◽

Open Source ◽

Field Trial ◽

Spatial Models ◽

R Package ◽

Field Trials ◽

Wheat Breeding ◽

Genetic Effects ◽

Agricultural Field ◽

Combining Data

Abstract Key message Established spatial models improve the analysis of agricultural field trials with or without genomic data and can be fitted with the open-source R package INLA. Abstract The objective of this paper was to fit different established spatial models for analysing agricultural field trials using the open-source R package INLA. Spatial variation is common in field trials, and accounting for it increases the accuracy of estimated genetic effects. However, this is still hindered by the lack of available software implementations. We compare some established spatial models and show possibilities for flexible modelling with respect to field trial design and joint modelling over multiple years and locations. We use a Bayesian framework and for statistical inference the integrated nested Laplace approximations (INLA) implemented in the R package INLA. The spatial models we use are the well-known independent row and column effects, separable first-order autoregressive ($$\mathrm{AR1} \otimes \mathrm{AR1}$$ AR 1 ⊗ AR 1 ) models and a Gaussian random field (Matérn) model that is approximated via the stochastic partial differential equation approach. The Matérn model can accommodate flexible field trial designs and yields interpretable parameters. We test the models in a simulation study imitating a wheat breeding programme with different levels of spatial variation, with and without genome-wide markers and with combining data over two locations, modelling spatial and genetic effects jointly. The results show comparable predictive performance for both the $$\mathrm{AR1} \otimes \mathrm{AR1}$$ AR 1 ⊗ AR 1 and the Matérn models. We also present an example of fitting the models to a real wheat breeding data and simulated tree breeding data with the Nelder wheel design to show the flexibility of the Matérn model and the R package INLA.

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