Publications by authors named "Sara San-Francisco"
Many studies have shown the close relationship between the beneficial action of soil and sedimentary humic acids on the growth of plants cultivated in calcareous soils and their ability to improve Fe plant nutrition. These results have been ascribed to the humic acid (HA) capability to improve Fe solubility and bioavailability. However, other effects more related to a humic acid action on the specific mechanisms activated in roots of plants under Fe deficiency cannot be ruled out.
View Article and Find Full Text PDFBackground: The release of phytosiderephores (PS) to the rhizosphere is the main root response to iron (Fe) deficiency in graminaceous plants. We have investigated the role of the Fe status in the shoot as well as of the signaling pathways controlled by three relevant phytoregulators - indolacetic acid (IAA), ethylene and nitric oxide (NO) - in the regulation of this root response in Fe-starved wheat plants. To this end, the PS accumulation in the nutrient solution and the root expression of the genes encoding the nicotianamine aminotransferase (TaNAAT) and ferritin (TaFER) have been evaluated in plants subjected to different treatments.
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- The study explores how no-tillage methods and soil characteristics impact nitrogen efficiency through the use of urease and nitrification inhibitors.
- Results show that urea causes higher ammonia volatilization than ammonium nitrate, with soil texture (clay vs. sand) significantly influencing this process.
- Organic residues from no-tillage increase ammonia loss, particularly in sandy soils, but the urease inhibitor NBPT effectively reduces this loss, especially in clay-rich soils despite lower efficiency in acidic conditions.
Article Synopsis
- The study focuses on the structural characteristics of specific compounds that inhibit urease, an enzyme found in jack beans, examining derivatives of phosphoramide and their relationship with urease activity.
- Molecular modeling revealed important factors influencing inhibition, like intramolecular hydrogen bonds, the volume of interacting fragments, degree of conformational freedom, and electron density distribution.
- Preliminary docking studies suggest a potential binding mode of these compounds to the active site of the urease enzyme.
The design, synthesis, and biological evaluation of phosphoramide derivatives as urease inhibitors to reduce the loss of ammonia has been carried out. Forty phosphorus derivatives were synthesized and their inhibitory activities evaluated against that of jack bean urease. In addition, in vivo assays have been carried out.
View Article and Find Full Text PDFTo optimize the economical cost of each unit of fertilizer applied and to reduce the environmental contamination caused by nutrient losses, the development of highly efficient granulated fertilizers is of great importance. This study proposes a strategy that consists of developing specific fertilizers having nutrient release patterns that are dependent on plant activity in the rhizosphere. This type of fertilizer is named "rhizosphere-controlled fertilizer" (RCF fertilizer).
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