Authors:H. Sonah, R. Deshmukh, S. Chand, M. Srinivasprasad, G. Rao, H. Upreti, A. Singh, N. Singh and T. Sharma
Flag leaf architecture is a very important trait which ensures the yield bearing capacity of plants by providing excellent source for photosynthesis. In this study, quantitative trait loci (QTLs) for flag leaf length and other traits were identified using rice recombinant inbred lines (RILs) derived from HP2216 × Tetep. A total of 12 QTLs were identified for the four traits located on seven different chromosomes of rice and analysis of interaction among the QTLs revealed additive effect for the leaf length and epistatic main effect for panicle length. More interestingly a QTL qLL12.1 responsible for the flag leaf length was identified on chromosome 12 within the marker interval RM247-RM6296 consistently at three climatic zones in India. Furthermore to saturate the qLL12.1 interval, additional 58 simple sequence repeat (SSR) markers were used for polymorphism survey which showed that qLL12.1 region was more conserved among parental lines. Finally, two polymorphic SSR markers were used for saturation of qLL12.1 region. Consequently, candidate gene approach was used to compliment QTL mapping. Co-localization of linkage map with physical map revealed 75 genes with evidence for expression. Functional annotation of these genes using in silico approaches and detailed literature search revealed nine candidate genes for flag leaf length. The stable QTL qLL12.1 identified in this study will provide starting point for map based cloning of leaf length related genes and tightly linked flanking markers can be used in marker assisted breeding programmes.
Authors:R. K. Singh, A. Narayan, K. Prasad, R. S. Yadav, A. C. Pandey, A. K. Singh, L. Verma and R. K. Verma
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.
Authors:A. Sabouri, M. Toorchi, B. Rabiei, S. Aharizad, A. Moumeni and R. Singh
L.) is one of the most important crops in the world, especially Asian countries. Genetics of important traits in rice for yield improvement have always been a major breeding objective. Agronomic traits are inherited quantitatively, so quantitative trait loci (QTL) mapping for the potential use of molecular markers would be very helpful to plant breeders in developing improved rice varieties. In this investigation, a SSR linkage map of 1440.7cM of rice was constructed using 105 polymorphic simple sequence repeat (SSR) markers. The mapping population of 236 F
families derived from the cross of two rice varieties (Gharib × Sepidroud) was used for QTL mapping of agronomic traits. As many as 38 QTLs were detected to be associated with agronomic characteristics; some of them are being reported for the first time. The identified QTLs on specific chromosome regions explaining high phenotypic variance could be considered to use in marker-assisted selection (MAS) programs.
Authors:R. Prasanna, S. A. Mohammadi, B. M. Prasanna and P. K. Singh
Twenty cyanobacterial strains of the genus Tolypothrix, including 15 strains of T. tenuis, three strains of T. ceylonica, and one each of T. nodosa and T. bouteillei, that were collected from various agro-ecological regions of India were evaluated for important parameters related to nitrogen fixing potential, such as acetylene reduction activity, total protein and chlorophyll content. Distinct differences were observed in nitrogen fixing potential at both inter- and intraspecific levels. The T. tenuis strains, in general, exhibited superior nitrogen fixing ability as compared to strains belonging to other species. A statistical procedure based on simultaneous consideration of performances of various strains with respect to different parameters under study aided in identification of three highly promising T. tenuis accessions, namely ARM586, ARM75 and ARM460, for potential exploitation as biofertilisers.
Authors:G. Chourasiya, R. Duggal, C. Singh, A. Rawat, S. Aggarwal and H. Jain
A direct evaporation method is described for the preparation of sources using stainless steel as the backing material and tetraethylene glycol (TEG) as a spreading agent in the presence of large amounts of uranium. It is shown that FWHM and tail contribution at the low energy peak due to energy degradation of the high energy peak can be optimized by heating the source under controlled conditions in a furnace at 500–600°C for about 15 min. An accuracy of 0.5–1% is demonstrated for the determination of238Pu/(239Pu+240Pu) alpha activity ratio in the U/Pu range of 10 to 1500 generally encountered in dissolver solution of irradiated fuel.
Authors:R. Parveen, F. J. Ahmad, Z. Iqbal, M. Singh, Y. T. Kamal and S. Ahmad
Andrographolide and betulinic acid are the terpenoids having potential anti-cancer activity. The cytotoxicity activity of both the drugs was carried out separately and in combination on liver cancer HepG2 cell lines. High-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) methods were developed and validated for simultaneous estimation of these two terpenoids as per the International Conference on Harmonization (ICH) guidelines, which was applied for quantification in nanoformulation. The retention time by HPLC and retardation factor by HPTLC for andrographolide and betulinic acid were found to be 2.2 and 6.6 min, and 0.24 ± 0.01 and 0.66 ± 0.01, respectively. Both the methods were validated for accuracy, precision, repeatability, robustness, limit of detection (LOD), and limit of quantitation (LOQ). The content of andrographolide and betulinic acid in nanoformulation was found to be 96.0% and 98.0% by HPLC and 96.59% and 98.33% by HPTLC, respectively, of labelled claim.
Authors:Y. T. Kamal, M. Singh, E. T. Tamboli, R. Parveen and S. Ahmad
A validated reversed-phase HPLC method has been developed for quantitative analysis of berberine in Berberis aristata fruits and in a polyherbal formulation. Separation of berberine was achieved on a C18 column with a mobile phase consisting of a 10–80% acetonitrile gradient in 0.05% aqueous orthophosphoric acid. The flow rate was 1 mL min−1. Detection was at 266 nm. A sharp, well defined peak was obtained at a retention time of 10.0 ± 0.4 min. The method was validated in accordance with ICH guidelines for accuracy, precision, robustness, and the limits of detection (LOD) and quantification (LOQ). Results from linear regression analysis were indicative of a good linear relationship (r2 = 0.998 ± 0.0011) in a wide concentration range (5–500 μ g mL−1). LOD and LOQ were 1.5 and 5.3 μg mL−1, respectively. Satisfactory recovery results (94.6–103.1%) were obtained by the method of standard addition. Intra-day, inter-day, and intersystem precision was satisfactory, with relative standard deviation in the range 0.7–1.8%. The berberine content of fruit of Berberis aristata and the herbal formulation were 0.033% and 0.0089% (w/w), respectively. This HPLC method for quantification of berberine can be used for quality control and standardization of several crude drugs and different herbal formulations in which berberine is present as a phyto constituent.
Authors:M. Kumar Raju, P. Sugathan, T. Seshi Reddy, B. Thirumala Rao, S. Muralithar, R. Singh, R. Bhowmik and P. Madhusudhana Rao
The high spin level structure of 73As nucleus is studied by populating the nucleus in 64Ni(12C,p2n)73As reaction. Level scheme is revised significantly. Positive parity sequence is extended up to 33/2+ and a negative parity side band is identified and extended up to high spins 37/2−. In addition about 15 new energy levels and a total of about 25 new gamma transitions were placed in the level scheme.
Authors:S. Aggarwal, A. Almaula, P. Khodade, A. Parab, R. Duggal, C. Singh, A. Rawat, G. Chourasiya, S. Chitambar and H. Jain
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.
Authors:M. Dowdall, Ø. Selnæs, W. Standring, S. Nielsen, L. del Risco Norrlid, S. Pálsson, T. Renvall and R. Singh Sidhu
Although high resolution gamma ray spectrometry serves as the primary analytical technique in emergency response situations,
chances for laboratories to practice analysing the type of spectra that may be expected in the early phase of such a situation
are limited. This problem is more acute for laboratories in countries that have no nuclear facilities. The analysis of synthetically
generated spectra may serve as a useful surrogate for actual spectra; this paper reports the results of a multilateral intercomparison
exercise conducted using such a spectrum. Results indicate that the laboratories involved appear to have no problems identifying
radioactive isotopes that regularly appear in national and international intercomparisons or exercises. However, some problems
are evident for isotopes that are less often encountered which may, however, occur during the early phases of a nuclear accident.
Isotopes prone to true coincidence summation proved also to be difficult with regard to correction of activities in some cases.
The synthesized spectrum constituted a useful means of comparative analysis of complex spectra multilaterally without the
impracticalities of using a sample drawn from a reactor.