Diacetylmonoxime Functionalized Silica Gel: An Efficient and Recyclable Organic Inorganic Hybrid Material for Selective Removal of Copper from Fly Ash Ameliorated Soil Samples

<div><p>A novel, efficient, highly stable, and reusable organic inorganic hybrid material was synthesized <i>via</i> silanization of silica gel with (3-aminopropyl)trimethoxysilane followed by covalent immobilization with diacetylmonoxime. The grafting was confirmed by FTIR, elemental analysis, ¹³C CPMAS NMR spectroscopy, SEM, TGA, and BET surface area analysis. The modified solid phase was found to be highly selective for Cu(II) ions under near neutral conditions with a high sorption capacity of 0.93 mmol·g⁻¹ and a preconcentration factor of 250. Isotherm and kinetic parameters correlated well with the Langmuir and pseudo-second-order model. The recovery of analyte was efficiently performed for ten consecutive adsorption-desorption cycles. The present environmentally benign and economical procedure was successfully applied for the separation and preconcentration of copper from fly ash ameliorated soil samples.</p> </div

Evaluation of 19,460 Wheat Accessions Conserved in the Indian National Genebank to Identify New Sources of Resistance to Rust and Spot Blotch Diseases

<div><p>A comprehensive germplasm evaluation study of wheat accessions conserved in the Indian National Genebank was conducted to identify sources of rust and spot blotch resistance. Genebank accessions comprising three species of wheat–<i>Triticum aestivum</i>, <i>T</i>. <i>durum</i> and <i>T</i>. <i>dicoccum</i> were screened sequentially at multiple disease hotspots, during the 2011–14 crop seasons, carrying only resistant accessions to the next step of evaluation. Wheat accessions which were found to be resistant in the field were then assayed for seedling resistance and profiled using molecular markers. In the primary evaluation, 19,460 accessions were screened at Wellington (Tamil Nadu), a hotspot for wheat rusts. We identified 4925 accessions to be resistant and these were further evaluated at Gurdaspur (Punjab), a hotspot for stripe rust and at Cooch Behar (West Bengal), a hotspot for spot blotch. The second round evaluation identified 498 accessions potentially resistant to multiple rusts and 868 accessions potentially resistant to spot blotch. Evaluation of rust resistant accessions for seedling resistance against seven virulent pathotypes of three rusts under artificial epiphytotic conditions identified 137 accessions potentially resistant to multiple rusts. Molecular analysis to identify different combinations of genetic loci imparting resistance to leaf rust, stem rust, stripe rust and spot blotch using linked molecular markers, identified 45 wheat accessions containing known resistance genes against all three rusts as well as a QTL for spot blotch resistance. The resistant germplasm accessions, particularly against stripe rust, identified in this study can be excellent potential candidates to be employed for breeding resistance into the background of high yielding wheat cultivars through conventional or molecular breeding approaches, and are expected to contribute toward food security at national and global levels.</p></div

Diversity among rust resistant genotypes based on profiles of linked molecular markers.

<p>Diversity among rust resistant genotypes based on profiles of linked molecular markers.</p

Seedling resistance in wheat accessions.

<p>These genebank accessions were identified as resistant in the primary field evaluation at the hotspots. The seedling resistance was recorded as resistant either to only one rust disease (leaf, stem or stripe) or a combination of two or all the three rust diseases. Seedling resistance screening was carried out under controlled condition at the Regional Station of Indian Institute of Wheat and Barley Research (IIWBR), Flowerdale, Shimla. Accession-wise details are provided in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167702#pone.0167702.s003" target="_blank">S3 Table</a>.</p

Locations of evaluation experiments of wheat germplasm against rusts and spot blotch.

<p>Primary screening against the three rusts was carried out at Wellington. Subsequent screening for stripe rust resistance was done at Gurdaspur and for spot blotch resistance at Cooch Behar. The seedling resistance assay was carried out at Flowerdale and molecular profiling was done at New Delhi. Base map was generated using DIVA-GIS data (<a href="http://www.diva-gis.org/gdata" target="_blank">www.diva-gis.org/gdata</a>).</p

Results of primary screening of wheat germplasm against three rusts.

<p>Stem: Stem rust; Leaf: Leaf rust; Stripe: Stripe rust S: Susceptible; MS: Moderately susceptible; MR: Moderately resistant; R: Resistant.</p

Experimental layout, flow of germplasm and salient results of the study.

<p>Blue filled boxes denote germplasm at various stages of the experiment. Trapezoids denote screening (green for field evaluation and red for lab assay). Figures and tables containing details corresponding to each stage of the flow are mentioned in italics below boxes.</p

Amplicon profile of 137 wheat accessions for SSR marker G<i>wm427</i> linked to <i>Sr13</i>. M = 100bp ladder.

<p>Amplicon profile of 137 wheat accessions for SSR marker G<i>wm427</i> linked to <i>Sr13</i>. M = 100bp ladder.</p

Gene combinations present in 137 wheat accessions.

<p>These wheat accessions were screened for the amplification of markers linked to five <i>Lr</i> genes, three <i>Sr</i> genes, four <i>Yr</i> genes and one spot blotch resistance QTL. Disease reaction recorded at Gurdaspur for yellow rust and at Cooch Behar for spot blotch are also given. R- resistant; MR- Moderately resistant; MS- moderately susceptible, S- susceptible and #N/A—no data.</p

Summary of evaluation of 4925 wheat accessions carried out at Gurdaspur for stripe rust and Cooch Behar for spot blotch.

<p>Summary of evaluation of 4925 wheat accessions carried out at Gurdaspur for stripe rust and Cooch Behar for spot blotch.</p