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One thousand four hundred and eighty three spring wheat germplasm (Triticum aestivum L.) lines comprising Indian as well as exotic lines were screened for resistance to spot blotch disease during winter 2014-15 at hot spot locations i.e., Banaras Hindu University, Varanasi and Uttar Banga Krishi Vishwavidyalaya, Cooch Behar. Severity of the disease at different stages beginning from tillering to dough stage was recorded. Location Severity Index (LSI) of Varanasi was higher than Cooch Behar. Twenty eight accessions were resistant or highly resistant at both locations. These 28 accessions were validated during the winter season (2015–2016). These germplasm were also evaluated at four environments for agronomic traits. Out of 28 accessions, seven (IC564121, IC529684, IC443669, IC443652, IC529962, IC548325 and EC178071-331) were highly resistant across the locations and over the years of study. These accessions comprised one exotic and six indigenous accessions belonging to Uttarakhand and Haryana. Two lines (IC529962 and IC443652) had higher yield than the best check at all the locations. These lines showing highly resistant reaction alongwith wider adaptability can be expedited for direct cultivation or for the development of high yielding and disease resistant cultivars. These lines can also be used for identification of novel resistance gene using allele mining tools and their deployment for the development of spot blotch resistant cultivars.

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Abstract

Magnetic nanoparticles of cobalt ferrite have been synthesized by citrate precursor method. TG-DSC studies have been made to get the idea of the optimum temperature of annealing that could lead to the formation of nanoparticles. Annealing the citrate precursor was done at 450, 650, and 973 °C. The X-ray diffraction (XRD) studies and the scanning electron microscopy (SEM) have been used for characterization. The data from vibrating sample magnetometer and photoluminescence spectrometer (PL) have been analyzed for exploring their applications. Using the Scherrer formula, the crystallite size was found to be 25, 32, and 43 nm, respectively, using the three temperatures. The particle size increased with annealing temperature. Rietveld refinements on the X-ray (XRD) data were done on the cobalt ferrite nanoparticles (monoclinic cells) obtained on annealing at 650 °C, selecting the space group P2/M. The values of coercivity (1574.4 G) and retentivity (18.705 emu g−1) were found out in the sample annealed at 650 °C while magnetization (39.032 emu g−1) was also found in the sample annealed at 973 °C. The photoluminescence (PL) property of these samples were studied using 225, 330, and 350 nm excitation wavelength radiation source. The PL intensity was found to be increasing with the particle size.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Aggarwal, A. Almaula, P. Khodade, A. Parab, R. Duggal, C. Singh, A. Rawat, G. Chourasiya, S. Chitambar, and H. Jain

Abstract  

K-factors (= certified isotope ratio/observed isotope ratio) are determined for the isotope abundance measurements of uranium and plutonium by thermal ionisation mass spectrometry. An mdf of 0.07% and 0.18% per mass unit differing by a factor of about 3, is obtained for uranium and plutonium, respectively, employing double rhenium filament assembly in the ion source and Faraday cup as the detector using the presently available isotopic reference materials of uranium and plutonium.

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The objective of this study was to develop and validate an assay method for simultaneous determination of atenolol, furosemide, losartan, and spironolactone in pharmaceutical formulations. A reverse-phase high-performance liquid chromatography procedure was developed, using a Kinetex® C-18 column (100 mm × 4.6 mm, 2.6 μm). The mobile phase was composed of methanol—water (75:25 v/v, pH 3.0, adjusted with phosphoric acid), with a flow rate of 0.4 mL min−1. All drugs were separated in less than 5 min. The method was validated according to International Conference on Harmonization (ICH) and Association of Official Analytical Chemists (AOAC) guidelines. The method showed linearity in a concentration range of 0.75–12.0 μg mL−1 for atenolol (r = 0.9995), 0.30–12.00 μg mL−1 for furosemide (r = 0.9997), 0.45–12.00 μg mL−1 for losartan (r = 0.9995), and 0.45–12.0 μg mL−1 for spironolactone (r = 0.9999). The method also showed repeatability and precision. The three-day average intra-day precisions were 101.35 ± 0.74% for atenolol, 95.84 ± 1.44% for furosemide, 98.90 ± 1.16% for losartan, and 97.19 ± 0.18% for spironolactone. Similarly, the inter-day precisions were 101.34 ± 0.72% for atenolol, 95.84 ± 0.1.50% for furosemide, 98.90 ± 1.17% for losartan, and 97.19 ± 0.83% for spironolactone. The method accuracy was also tested and validated — in this case, the average recovery values were 100.18 ± 1.20% for atenolol, 99.83 ± 1.54% for furosemide, 100.07 ± 0.95% for losartan, and 99.94 ± 0.93% for spironolactone. Finally, the method was successfully applied in the simultaneous determination of atenolol, furosemide, losartan, and spironolactone in magisterial formulas, as well as in commercial pharmaceutical formulations.

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Cereal Research Communications
Authors: S. L. Krishnamurthy, S. K. Sharma, D. K. Sharma, P. C. Sharma, Y. P. Singh, V. K. Mishra, D. Burman, B. Maji, B. K. Bandyopadhyay, S. Mandal, S. K. Sarangi, R. K. Gautam, P. K. Singh, K. K. Manohara, B. C. Marandi, D. P. Singh, G. Padmavathi, P. B. Vanve, K. D. Patil, S. Thirumeni, O. P. Verma, A. H. Khan, S. Tiwari, M. Shakila, A. M. Ismail, G. B. Gregorio, and R. K. Singh

Genotype × environment (G × E) interaction effects are of special interest for identifying the most suitable genotypes with respect to target environments, representative locations and other specific stresses. Twenty-two advanced breeding lines contributed by the national partners of the Salinity Tolerance Breeding Network (STBN) along with four checks were evaluated across 12 different salt affected sites comprising five coastal saline and seven alkaline environments in India. The study was conducted to assess the G × E interaction and stability of advanced breeding lines for yield and yield components using additive main effects and multiplicative interaction (AMMI) model. In the AMMI1 biplot, there were two mega-environments (ME) includes ME-A as CARI, KARAIKAL, TRICHY and NDUAT with winning genotype CSR 2K 262; and ME-B as KARSO, LUCKN, KARSA, GOA, CRRI, DRR, BIHAR and PANVE with winning genotypes CSR 36. Genotypes CSR 2K 262, CSR 27, NDRK 11-4, NDRK 11-3, NDRK 11-2, CSR 2K 255 and PNL 1-1-1-6-7-1 were identified as specifically adapted to favorable locations. The stability and adaptability of AMMI indicated that the best yielding genotypes were CSR 2K 262 for both coastal saline and alkaline environments and CSR 36 for alkaline environment. CARI and PANVEL were found as the most discernible environments for genotypic performance because of the greatest GE interaction. The genotype CSR 36 is specifically adapted to coastal saline environments GOA, KARSO, DRR, CRRI and BIHAR and while genotype CSR 2K 262 adapted to alkaline environments LUCKN, NDUAT, TRICH and KARAI. Use of most adapted lines could be used directly as varieties. Using them as donors for wide or specific adaptability with selection in the target environment offers the best opportunity for widening the genetic base of coastal salinity and alkalinity stress tolerance and development of adapted genotypes. Highly stable genotypes can improve the rice productivity in salt-affected areas and ensure livelihood of the resource poor farming communities.

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Cereal Research Communications
Authors: N. Jain, G.P. Singh, R. Yadav, R. Pandey, P. Ramya, M.B. Shine, V.C. Pandey, N. Rai, J. Jha, and K.V. Prabhu

Under limiting water resources, root system response of genotypes to soil-water conditions with enhanced shoot biomass holds the key for development of improved genotypes. Based on the hypothesis of root biomass contribution to higher yields under limiting conditions which might be attributed to the root system plasticity of genotypes, a set of thirty-four genotypes were evaluated under three moisture regimes in a pot experiment for root system traits. Total root dry matter had a positive association with total shoot dry matter (0.35). The identified genotypes showed greater yields and higher stress tolerance index (STI) in an independent field experiment. Root dry matter positively correlated with stress tolerance index on grain yields in both the years. The total variation was partitioned into principal components and GGE biplots were studied to identify the best performing genotypes under the three environments for root dry biomass and related traits. HD2932 appeared to be the winner genotype under different regimes. These results might be helpful in identifying donors for moisture stress tolerance that can be utilized in wheat breeding programmes for accelerated development of varieties with improved root systems.

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The present study aimed to develop and validate an analytical method for determination of marbofloxacin (MAR) in veterinary chewable tablets. The isocratic reversed-phase chromatographic method was developed and validated using a Vertisep®, RP C18 column (150 mm × 4.6 mm, 5.0 μm). The mobile phase was composed of water–acetonitrile (55:45, v/v) with pH adjusted to 3.0 with ortho-phosphoric acid and a flow rate set at 0.4 mL/min. The proposed method was validated for linearity in a concentration range of 2.5 to 17.5 μg/mL with a correlation coefficient of 0.99991. The mean content of MAR found in chewable tablets was 104.40% with RSD below 2%. The accuracy expressed as average recovery of the proposed method was 98.74%, and the precision expressed as relative standard deviation among repeated analysis was 0.55%. The method has adequate sensitivity with detection and quantitation limits of 0.25 and 0.81 μg/mL, respectively. Based on the presented results and according to the ICH and AOAC guidelines on validation of analytical methods, the proposed method was considered precise, accurate with adequate sensitivity, and robust in the MAR quantitative analysis. Therefore, the method can be used in the quality control of chewable veterinary tablets containing MAR.

Open access
Cereal Research Communications
Authors: B. Kumar, K.S. Hooda, R. Gogoi, V. Kumar, S. Kumar, A. Abhishek, P. Bhati, J.C. Sekhar, K.R. Yathish, V. Singh, A. Das, G. Mukri, E. Varghese, H. Kaur, V. Malik, and O.P. Yadav

Maydis leaf blight (MLB), a serious foliar fungal disease of maize, may cause up to 40% losses in yield. The present studies were undertaken to identify the stable sources of MLB resistance, its inheritance study, and testing of MLB resistance linked markers from diverse background in the Indian adapted tropical maize genotypes. A set of 112 inbred lines were screened under artificially created epiphytotics conditions at three hotspot locations. Analysis across multi-locations revealed significant effects of genotypes and environments, and non-significant effects due to genotypes × environment interaction on disease incidence. A total of 25 inbred lines with stable resistance were identified across multi-locations. Inheritance of resistance was studied in six F1s and two F2s of resistant and susceptible parents. The null hypothesis of segregation of resistance and susceptible for mono and digenic ratios in two F2 populations was rejected by Chi-square test. The non-significant differences among the reciprocal crosses depicted the complete control of nuclear genome for MLB resistance. Partial dominance in F1s and normal distribution pattern in F2s of resistant and susceptible parents suggested polygenic nature of MLB resistance. Correlation studies in F2 populations exhibited significant negative correlation between disease score and days to flowering. Five simple sequence repeats (SSRs) markers, found associated to MLB resistance in different studies were unable to differentiate amongst MLB resistance and susceptible parents in our study. This emphasizes the need of fine mapping for MLB resistance in Indian germplasm. The identified stable sources of resistance and information on inheritance study can be used further in strengthening of resistance breeding against MLB.

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Acta Chromatographica
Authors: Azazahemad A. Kureshi, Chirag Dholakiya, Tabaruk Hussain, Amit Mirgal, Siddhesh P. Salvi, Pritam C. Barua, Madhumita Talukdar, C. Beena, Ashish Kar, T. John Zachariah, Premlata Kumari, Tushar Dhanani, Raghuraj Singh, and Satyanshu Kumar

Xanthones are well recognized as chemotaxonomic markers for the plants belonging to the genus Garcinia. Xanthones have many interesting pharmacological properties. Efficient extraction and rapid liquid chromatography methods are essentially required for qualitative and quantitative determination of xanthones in their natural sources. In the present investigation, fruit rinds extracts of 8 Garcinia species from India, were prepared with solvents of varying polarity. Identification and quantification of 3 xanthones, namely, α-mangostin, β-mangostin, and γ-mangostin in these extracts were carried out using a rapid and validated ultra-high-performance liquid chromatography–photodiode array detection (UHPLC–PDA) method at 254 nm. γ-Mangostin (3.97 ± 0.05 min) was first eluted, and it was followed by α-mangostin (4.68 ± 0.03 min) and β-mangostin (5.60 ± 0.04 min). The calibration curve for α-mangostin, β-mangostin, and γ- mangostin was linear in the concentration range 0.781–100 μg/mL. α-Mangostin was quantified in all 4 extracts of Garcinia mangostana. Its content (%) in hexane, chloroform, ethyl acetate, and methanol extracts of G. mangostana was 10.36 ± 0.10, 4.88 ± 0.01, 3.98 ± 0.004, and 0.044 ± 0.002, respectively. However, the content of α-mangostin was below the limit of detection or limit of quantification in the extracts of other Garcinia species. Similarly, β-mangostin was quantified only in hexane (1.17 ± 0.01%), chloroform (0.39 ± 0.07%), and ethyl acetate (0.28 ± 0.03%) extracts of G. mangostana. γ-Mangostin was quantified in all 4 extracts of G. mangostana. Its content (%) in hexane, chloroform, ethyl acetate, and methanol extracts of G. mangostana was 0.84 ± 0.01, 1.04 ± 0.01, 0.63 ± 0.04, and 0.15 ± 0.01, respectively. γ-Mangostin was also quantified in hexane (0.09 ± 0.01), chloroform (0.05 ± 0.01), and ethyl acetate (0.03 ± 0.01) extracts of G. cowa, ethyl acetate extract of G. cambogia (0.02 ± 0.01), G. indica (0.03 ± 0.01), and G. loniceroides (0.07 ± 0.01). Similarly, γ-mangostin was quantified in 3 extracts of G. morella, namely, hexane (0.03 ± 0.01), chloroform (0.04 ± 0.01), and methanol (0.03 ± 0.01). In the case of G. xanthochymus, γ-mangostin was quantified in chloroform (0.03 ± 0.001) extract only. α-Mangostin and β-mangostin were not detected in any of 4 extracts of G. pedunculata.

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