660 publications from this institution
Iron (Fe) deficiency in plants is a common problem affecting agricultural production. Cadmium (Cd) is a toxic metal that can be taken up and transported wi
UK crops have a low selenium (Se) status, therefore Se fertilisation of wheat (Triticum aestivum L.) at 10 field sites was investigated and the effect on t
Aim To investigate broad‐scale patterns of plant leaf ash content and their possible causes in China. Location Mainland China and Hainan island, with the geographic ranges for the data used from 18.7° N to 49.2° N and 76.0° E to 128.3° E. Methods By analysing a data set of 2022 leaf samples, involving 704 species of terrestrial plants. Results Leaf ash content increases with increasing latitude at an average rate of 2.7 mg ash g −1 dry weight per degree latitude from south to north of China. Plant functional group shows a more powerful influence on the spatial variation in leaf ash than soil pH and climate. Fast‐growing species or those with leaves with a short life span have higher leaf ash than slow‐growing species or those with a long leaf life span. Plants from alkaline soils have higher leaf ash than those from acid soils (39.5 mg g −1 increase in leaf ash content per unit increase of pH). Increasing precipitation significantly reduces leaf ash (with a mean rate of 4.8 mg g −1 for every 100 mm rainfall), whereas the effect of temperature appears to be nonlinear. Main conclusions This study shows a significant latitudinal trend in leaf ash content in China. This geographic pattern is possibly shaped by the floral, edaphic and climatic factors that control the biogeochemical cycling of plant minerals. The results suggest that leaf ash content is a useful biogeographic indicator that can be used to explore the complex interactions between plants and the environment.
Sulfur (S) is an essential mineral nutrient required for plant growth and development. Plants usually face temporal and spatial variation in sulfur availability, including the heterogeneous sulfate content in soils. As sessile organisms, plants have evolved sophisticated mechanisms to modify their gene expression and physiological processes in order to optimize S acquisition and usage. Such plasticity relies on a complicated network to locally sense S availability and systemically respond to S status, which remains poorly understood. Here, we took advantage of a split-root system and performed transcriptome-wide gene expression analysis on rice plants in S deficiency followed by sulfate resupply. S deficiency altered the expressions of 6749 and 1589 genes in roots and shoots, respectively, accounting for 18.07% and 4.28% of total transcripts detected. Homogeneous sulfate resupply in both split-root halves recovered the expression of 27.06% of S-deficiency-responsive genes in shoots, while 20.76% of S-deficiency-responsive genes were recovered by heterogeneous sulfate resupply with only one split-root half being resupplied with sulfate. The local sulfate resupply response genes with expressions only recovered in the split-root half resupplied with sulfate but not in the other half remained in S deficiency were identified in roots, which were mainly enriched in cellular amino acid metabolic process and root growth and development. Several systemic response genes were also identified in roots, whose expressions remained unchanged in the split-root half resupplied with sulfate but were recovered in the other split-root half without sulfate resupply. The systemic response genes were mainly related to calcium signaling and auxin and ABA signaling. In addition, a large number of S-deficiency-responsive genes exhibited simultaneous local and systemic responses to sulfate resupply, such as the sulfate transporter gene OsSULTR1;1 and the O-acetylserine (thiol) lyase gene, highlighting the existence of a systemic regulation of sulfate uptake and assimilation in S deficiency plants followed by sulfate resupply. Our studies provided a comprehensive transcriptome-wide picture of a local and systemic response to heterogeneous sulfate resupply, which will facilitate an understanding of the systemic regulation of S homeostasis in rice.
The selenium concentration of representative bread‐making wheat ( Triticum aestivum L) samples was measured in national grain surveys collected in 1982 ( n (number of samples) = 180), 1992 ( n = 187) and 1998 ( n = 85) from major wheat‐growing regions around the UK. The means and distributions of selenium concentrations over the three years were similar, with mean grain concentrations of 0.025, 0.033 and 0.025 mg kg −1 dry weight respectively and inter‐quartile ranges varying from 0.015 mg kg −1 in 1982 to 0.019 mg kg −1 in 1992 samples. No long‐term changes in the distribution of wheat selenium concentrations were found over the 17 year period. Geographical mapping of the concentrations identified an area of eastern England as having high grain concentrations compared with other UK regions. There were no significant correlations between grain selenium and grain sulphur concentrations for the national survey samples. However, at an individual field experimental site, increasing the rate of sulphur addition was found to decrease grain selenium concentration significantly. The daily UK dietary contribution of selenium from wheat‐based products was estimated and the daily intake was calculated to be 6.4 µg selenium, around one‐tenth of the UK recommended intake values for men and women. © 2002 Society of Chemical Industry
Current definitions of essential or beneficial elements for plant growth rely on narrowly defined criteria that do not fully represent a new vision for plant nutrition and compromise fertilizer regulation and practice. A new definition of what is a plant nutrient that is founded in science and relevant in practice has the potential to revitalize innovation and discovery. A proposed new definition might read: A mineral plant nutrient is an element which is essential or beneficial for plant growth and development or for the quality attributes of the plant or harvested product, of a given plant species, grown in its natural or cultivated environment. A plant nutrient may be considered essential if the life cycle of a diversity of plant species cannot be completed in the absence of the element. A plant nutrient may be considered beneficial if it does not meet the criteria of essentiality, but can be shown to benefit plant growth and development or the quality attributes of a plant or its harvested product . It includes elements currently identified as essential, elements for which a clear plant metabolic function has been identified, as well as elements that have demonstrated clear benefits to plant productivity, crop quality, resource use efficiency, stress tolerance or pest and disease resistance. We propose an open scientific debate to refine and implement this updated definition of plant nutrients. Other outcomes of this debate could be a more precise definition of the experimental evidence required to classify an element as a plant nutrient, and an independent scientific body to regularly review the list of essential and beneficial nutrients. The debate could also attempt to refine the definition of plant nutrients to better align with nutrients deemed essential for animal and human nutrition, thus following a more holistic ’one nutrition‘ concept.
No abstract is provided for this article.
No abstract is provided for this article.
Cadmium (Cd) is a naturally occurring element present in all soils from both geogenic and anthropogenic sources. The primary risk pathway to humans is exposure through dietary intake in foods and by inhalation through smoking, with the target affected organ being the kidney. In developed countries, Cd intakes by populations are below levels of concern as determined by the World Health Organization. However, in some developing countries Cd intakes are increasing, so management of Cd transfer through the food chain remains important to minimize human exposure. Significant advances have been made in understanding the behavior of Cd in agricultural systems and a range of management options are now available for farmers to minimize uptake into crops and forages. Our understanding of the genetics of root Cd uptake, translocation and accumulation in shoots, grains and tubers has advanced significantly and farmers now have the option to manage Cd through choice of crop and/or new low-Cd cultivars. High-risk soils can now be identified by soil testing and various agronomic options are available to minimize plant uptake on these high-risk soils. Combined, these management options can rapidly reduce Cd concentrations in foods, quicker than reductions in Cd inputs in fertilizers, manures or atmospheric sources. However, it is important that we limit Cd accumulation in soils and aim for zero-net accumulation. Calculating limits to Cd inputs necessary to achieve this are compromised by the lack of accurate information on measurement of rates of Cd leaching under field conditions.
Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.
This paper reviews the recent advances in understanding of metal removal from contaminated soils, using either hyperaccumulator plants, or high biomass crop species after soil treatment with chelating compounds. Progress has been made at the physiology and molecular...
No abstract is provided for this article.
