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Arnold J. Bloom

Bio: Arnold J. Bloom is an academic researcher from University of California, Davis. The author has contributed to research in topics: Ammonium & Nitrate. The author has an hindex of 42, co-authored 96 publications receiving 10167 citations. Previous affiliations of Arnold J. Bloom include Stanford University & University of California, Berkeley.


Papers
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Journal ArticleDOI
TL;DR: Revue bibliographique suggerant que, au moins pour la croissance vegetative les plantes fonctionnent conformement aux theoremes economiques: optimiser les profits and repartir de facon optimale les ressources.
Abstract: Revue bibliographique suggerant que, au moins pour la croissance vegetative les plantes fonctionnent conformement aux theoremes economiques: optimiser les profits et repartir de facon optimale les ressources

2,376 citations

Journal ArticleDOI
TL;DR: Plant growth in diverse environments requires a similar balance of resources-energy, water, and mineral nutrients-to maintain optimal growth, but these resources differ by at least two orders of magnitude in the availability.
Abstract: M ost plants require a similar balance of resources-energy, water, and mineral nutrients-to maintain optimal growth. Natural environments, however, differ by at least two orders of magnitude in the availability of these resources. Light intensity varies 100fold from the canopy to the floor of a rainforest (Bj6rkman 1981); annual precipitation ranges 500-fold (105000 mm/yr) from deserts to tropical rainforests; and the amount of nitrogen available to plants varies from 0.09 g/m2 * yr in polar desert (Dowding et al. 1981) to 22.8 g/m2 * yr in a rich tropical rainforest (Vitousek 1984). Plants growing in these diverse environments maintain tissue concen-

1,215 citations

Journal ArticleDOI
05 Jun 2014-Nature
TL;DR: It is reported that C3 grains and legumes have lower concentrations of zinc and iron when grown under field conditions at the elevated atmospheric CO2 concentration predicted for the middle of this century.
Abstract: experiments contribute more than tenfold more data regarding both the zinc and iron content of the edible portions of crops grown under FACE conditions than is currently available in the literature. Consistent with earlier meta-analyses of other aspects of plant function under FACE conditions 14,15 , we considered the response comparisons observed from different species, cultivars and stress treatments and from different years to be independent. The natural logarithm of the mean response ratio (r5 response in elevated [CO2]/response in ambient [CO2]) was used as the metric for all analyses. Meta-analysis was used to estimate the overall effect of elevated [CO2] on the concentration of each nutrient in a particular crop and to determine the significance of this effect (see Methods). We found that elevated [CO2] was associated with significant decreases in the concentrations of zinc and iron in all C3 grasses and legumes (Fig. 1 and Extended Data Table 1). For example, wheat grains grown at elevated [CO2] had 9.3% lower zinc (95% confidence interval (CI)212.7% to25.9%) and 5.1% lower iron (95% CI26.5% to23.7%) than those grown at ambient [CO2]. We also found that elevated [CO2] was associated with lower protein content in C3 grasses, with a 6.3% decrease (95% CI27.5% to25.2%) in wheat grains and a 7.8% decrease (95% CI 28.9% to26.8%) in rice grains. Elevated [CO2] was associated with a small decrease in protein in field peas, and there was no significant

948 citations

Journal ArticleDOI
TL;DR: The genes, pathways, and signaling functions of photorespiration are considered here in the context of whole plant biology, with reference to future challenges and human interventions to diminish photorespiratory flux.
Abstract: Photorespiration is a high-flux pathway that operates alongside carbon assimilation in C(3) plants. Because most higher plant species photosynthesize using only the C(3) pathway, photorespiration has a major impact on cellular metabolism, particularly under high light, high temperatures, and CO(2) or water deficits. Although the functions of photorespiration remain controversial, it is widely accepted that this pathway influences a wide range of processes from bioenergetics, photosystem II function, and carbon metabolism to nitrogen assimilation and respiration. Crucially, the photorespiratory pathway is a major source of H(2)O(2) in photosynthetic cells. Through H(2)O(2) production and pyridine nucleotide interactions, photorespiration makes a key contribution to cellular redox homeostasis. In so doing, it influences multiple signaling pathways, particularly those that govern plant hormonal responses controlling growth, environmental and defense responses, and programmed cell death. The potential influence of photorespiration on cell physiology and fate is thus complex and wide ranging. The genes, pathways, and signaling functions of photorespiration are considered here in the context of whole plant biology, with reference to future challenges and human interventions to diminish photorespiratory flux.

535 citations

Journal ArticleDOI
14 May 2010-Science
TL;DR: Evidence is presented that carbon dioxide inhibition of nitrate assimilation is a major determinant of plant responses to rising atmospheric concentrations of carbon dioxide, and that the relative availability of soil ammonium and nitrate to most plants will become increasingly important in determining their productivity as well as their quality as food.
Abstract: The concentration of carbon dioxide in Earth's atmosphere may double by the end of the 21st century. The response of higher plants to a carbon dioxide doubling often includes a decline in their nitrogen status, but the reasons for this decline have been uncertain. We used five independent methods with wheat and Arabidopsis to show that atmospheric carbon dioxide enrichment inhibited the assimilation of nitrate into organic nitrogen compounds. This inhibition may be largely responsible for carbon dioxide acclimation, the decrease in photosynthesis and growth of plants conducting C(3) carbon fixation after long exposures (days to years) to carbon dioxide enrichment. These results suggest that the relative availability of soil ammonium and nitrate to most plants will become increasingly important in determining their productivity as well as their quality as food.

498 citations


Cited by
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Journal ArticleDOI
22 Apr 2004-Nature
TL;DR: Reliable quantification of the leaf economics spectrum and its interaction with climate will prove valuable for modelling nutrient fluxes and vegetation boundaries under changing land-use and climate.
Abstract: Bringing together leaf trait data spanning 2,548 species and 175 sites we describe, for the first time at global scale, a universal spectrum of leaf economics consisting of key chemical, structural and physiological properties. The spectrum runs from quick to slow return on investments of nutrients and dry mass in leaves, and operates largely independently of growth form, plant functional type or biome. Categories along the spectrum would, in general, describe leaf economic variation at the global scale better than plant functional types, because functional types overlap substantially in their leaf traits. Overall, modulation of leaf traits and trait relationships by climate is surprisingly modest, although some striking and significant patterns can be seen. Reliable quantification of the leaf economics spectrum and its interaction with climate will prove valuable for modelling nutrient fluxes and vegetation boundaries under changing land-use and climate.

6,360 citations

Journal ArticleDOI
01 Jan 1989
TL;DR: In this article, the physical and enzymatic bases of carbone isotope discrimination during photosynthesis were discussed, noting how knowledge of discrimination can be used to provide additional insight into photosynthetic metabolism and the environmental influences on that process.
Abstract: We discuss the physical and enzymatic bases of carbone isotope discrimination during photosynthesis, noting how knowledge of discrimination can be used to provide additional insight into photosynthetic metabolism and the environmental influences on that process

6,246 citations

Journal ArticleDOI
TL;DR: Food in the Anthropocene : the EAT-Lancet Commission on healthy diets from sustainable food systems focuses on meat, fish, vegetables and fruit as sources of protein.

4,710 citations

Journal ArticleDOI
TL;DR: The nature of crop responses to nutrient stress is reviewed and compares these responses to those of species that have evolved under more natural conditions, particularly in low-nutrient envi­ ronments.
Abstract: Our understanding of plant mineral nutrition comes largely from studies of herbaceous crops that evolved from ruderal species characteristic of nutri­ ent-rich disturbed sites (52). With the development of agriculture, these ancestral species were bred for greater productivity and reproductive output at high nutrient levels where there was little selective advantage in efficient nutrient use. This paper briefly reviews the nature of crop responses to nutrient stress and compares these responses to those of species that have evolved under more natural conditions, particularly in low-nutrient envi­ ronments. I draw primarily upon nutritional studies of nitrogen and phos­ phorus because these elements most commonly limit plant growth and because their role in controlling plant growth and metabolism is most clearly understood (51). Other more specific aspects of nutritional plant ecology not discussed here include ammonium/nitrate nutrition (79), cal­ cicole/calcifuge nutrition (51,88), heavy metal tolerance (4), and serpentine ecology (133).

4,176 citations

Book
01 Jan 1982
TL;DR: In this article, the Soil as a Plant Nutrient Medium is discussed and the importance of water relations in plant growth and crop production, and the role of water as a plant nutrient medium.
Abstract: 1. Plant Nutrients. 2. The Soil as a Plant Nutrient Medium. 3. Nutrient Uptake and Assimilation. 4. Plant Water Relationships. 5. Plant Growth and Crop Production. 6. Fertilizer Application. 7. Nitrogen. 8. Sulphur. 9. Phosphorus. 10. Potassium. 11. Calcium. 12. Magnesium. 13. Iron. 14. Manganese. 15. Zinc. 16. Copper. 17. Molybdenum. 18. Boron. 19. Further Elements of Importance. 20. Elements with More Toxic Effects. General Readings. References. Index.

4,130 citations