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Artemisia annua is the source of antimalarial phytomolecule, artemisinin. It is mainly produced and stored in the glandular secretory trichomes present in the leaves of the plant. Since, the artemisinin biosynthesis steps are yet to be worked out, in this investigation a microarray chip was strategized for the first time to shortlist the differentially expressing genes at a stage of plant producing highest artemisinin compared to the stage with no artemisinin. As the target of this study was to analyze differential gene expression associated with contrasting artemisinin content in planta and a genotype having zero/negligible artemisinin content was unavailable, it was decided to compare different stages of the same genotype with contrasting artemisinin content (seedling - negligible artemisinin, mature leaf - high artemisinin). The SCAR-marked artemisinin-rich (∼1.2%) Indian variety ‘CIM-Arogya’ was used in the present study to determine optimal plant stage and leaf ontogenic level for artemisinin content. A representative EST dataset from leaf trichome at the stage of maximal artemisinin biosynthesis was established. The high utility small scale custom microarray chip of A. annua containing all the significant artemisinin biosynthesis-related genes, the established EST dataset, gene sequences isolated in-house and strategically selected candidates from the A. annua Unigene database (NCBI) was employed to compare the gene expression profiles of two stages. The expression data was validated through semiquantitative and quantitative RT-PCR followed by putative annotations through bioinformatics-based approaches. Many candidates having probable role in artemisinin metabolism were identified and described with scope for further functional characterization.

The application of organic amendments in agroecosystems has been widely recommended, but the impact of their C/N ratio on the stabilization and sequestration of soil organic carbon (SOC) is often unaccounted for. The influence of the C/N ratio of amendments on soil physicochemical properties in a rice (Oryza sativa var. NDR97)–barley (Hordeum vulgare var. Lakhan) rotation tropical dryland agroecosystem was compared with an undisturbed grassland. Chemical fertilizer in the form of urea and three organic inputs (Sesbania aculeata shoot, low C/N ratio; air‐dried straw of wheat (Triticum aestivum var. Malviya 533), high C/N ratio; and S. aculeata shoot+wheat straw, high and low C/N ratio combined) carrying an equivalent amount of N, were added to plots of the agroecosystem once during each annual cycle. Soil water‐holding capacity (WHC), porosity, SOC, total N, and aggregate stability were improved in the wheat straw and S. aculeata shoot+wheat straw treatments, reaching levels comparable with the grassland. Soil WHC, porosity, and SOC influenced the productivity of the grassland and the agroecosystem. The grassland recorded highest SOC (53% higher relative to control) followed by the wheat straw (+47%), S. aculeata shoot+wheat straw (+37%) and soil total N was greatest in the S. aculeata shoot+wheat straw treatment (+37.5%). Aggregate stability and macroaggregate distribution were also higher in the wheat straw and S. aculeata shoot+wheat straw treatments, however, the microaggregate and silt + clay fractions showed a reverse trend. Management practices with a higher residue‐C return in the agroecosystem resulted in increased aggregate stability and aggregate‐associated SOC, with C storage attaining levels similar to the natural system.

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This paper describes the entire methodology for the development of a scale to measure Attitude towards Open Educational Resources (ATOER). Traditionally, it is observed that some teachers are more willing to share their work than others, indicating the need to understand teachers' psychological and behavioural determinants that influence use of OER. The paper presents the methodological rigour in the development of the 17 items two-factor scale that is valid and reliable to measure attitude towards OER. The psychometric properties of the scale include: Content Validity Ratio=0.9 and Cronbach α=0.897 with strong inter-items correlation. The two-factors attitude construct in the scale was also subjected to a good model fit using Structural Equation Modelling, which revealed a mediocre fit with 0.8 Root Mean Square Error Approximation value and the chi-square to degree of freedom ratio below 3.We also discuss the significance of the scale and how to use it with other variables effectively in different contexts to help develop appropriate strategies for promoting the use of OER in educational institutions.

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