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  • Author or Editor: A. Gupta x
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The results of a field study revealed that the application of fertilizers to the companion crop in a millet/legume intercropping system is essential to optimize the yield of the legume component. Supplying nutrients to the main crop alone tended to decrease the productivity of the companion crop, probably because of shading as a result of overgrowth of the main crop. The highest contents of N and P in the grain and straw of the intercrop were recorded with 100% of the recommended dose to both the component crops (M100I100). However, the uptake of nutrients was highest from the plots receiving 50 and 100% of the recommended dose to the main and companion crop, respectively (M50I100). Higher uptake was due to the fact that the yields increased to a greater extent than the nutrient concentrations.

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Abstract  

Sorption of Li+, Cs+ and Sr2+ on hydrous titanium oxide and magnetite as a function of pH in the presence and absence of -rays has been studied. pH-titrations of the irradiated hydrous oxides have also been carried out. It has been shown that the sorption characteristics of these oxides are not altered by -irradiation and the uptake of metal ions is governed by the equilibrium pH of the solution. Certain physical changes observed on irradiating of the hydrous oxide samples in water are discussed.

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Abstract  

The extraction behavior of uranium, thorium and lanthanides, represented by cerium and ytterbium, by Cyanex-923 has been investigated. The effect of different variables like the concentration of acids, metal ion and extractant, nature of diluent and temperature has been studied. A composition for the extracted U(VI) and Th(IV) species has been proposed. Based on the partition data some important binary and ternary separations involving the aforesaid metal ions have been achieved. The proposed procedure has been applied for the recovery of uranium, thorium and lanthanide fraction from monazite sand. The stability and regeneration capacity of the extractant have been evaluated.

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The present study reports the effects of pre-treatment with ferulic acid (FA) on antioxidant response of wheat seedlings. In comparison to hydropriming, 100 and 150 ppm of FA significantly enhanced seedling growth of wheat at 6th day after germination (DAG). However, 1000 ppm of FA led to reduction in seedling growth. Roots and shoots of wheat seedlings pre-treated with 100 ppm of FA showed significant upregulation of peroxidase (POX), ascorbate peroxidase (APX) activities. Although catalase (CAT) remained unaffected in the roots, but showed about 2-fold increase in the shoots. Despite of low glutathione reductase (GR) and high polyphenol oxidase (PPO) activities in the shoots and roots, respectively, ascorbic acid and total phenolic contents also increased at 6th DAG which may be due to the activation of their biosynthetic pathways in seedlings pre-treated with 100 ppm of FA. Proline content of wheat seedlings pre-treated with 100 ppm of FA remained unaffected. Results signify the role of FA pre-treatment in augmenting the antioxidant response of wheat and thereby suggest that at lower concentrations, it can be used for improving performance of wheat under various environmental constraints.

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An online-hyphenated high-performance liquid chromatography-photodiode array-mass spectrometry (HPLC-PDA-MS) analytical method was developed for the simultaneous determination of six lignans of therapeutic importance in four Phyllanthus spp. (P. amarus, P. maderaspatensis, P. urinaria, and P. virgatus). HPLC with monolithic reverse phase silica column (4.6 × 100 mm) and simple isocratic elution of methanol-water mixed with dioxane facilitated the separation of lignans of diverse nature such as diarylbutyrolactone, tetrahydrofuran, isomeric aryltetralin, and diarylbutane type for quantitative analysis. Targeted lignans viz. heliobuphthalmin lactone (1), virgatusin (2), hypophyllanthin (3), phyllanthin (4), nirtetralin (5), and niranthin (6) were confirmed unambiguously in four Phyllanthus species by their abundant molecular adduct ions, retention time, UV, and mass spectra as compared with those of reference compounds. Advantages and limitations of both detection techniques for qualitative (fingerprinting) and quantitative analysis of the above mentioned lignans in four Phyllanthus spp. are discussed. The method was validated following international guidelines. The described method can be utilized for assays and stability tests of P. amarus extracts as well as traditional Indian medicine based on Phyllanthus herb.

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Crop productivity is greatly influenced by various environmental stresses, of which insect herbivory-induced biotic stress assumes much significance. As a consequence of insect herbivory, a number of plant biochemical processes involved in the tolerance mechanism are affected. Different studies have demonstrated a diverse functional role of various plant oxidative enzymes in protecting plants against biotic stress induced by insect herbivory. Comprehensive profiling of stress-associated plant oxidative enzymes is most relevant to successful molecular breeding of stress-tolerant crop plants. Thus, better understanding of the biochemical basis of plant defense mechanisms is imperative, not only from a basic science perspective, but also for biotechnology-based pest control practice. In this review, we emphasize the potential role of various oxidative enzymes in plant defense against insect herbivory.

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Grain and malt traits important for malting quality were studied on a set of 131 genotypes including two and six row types barley of indigenous and exotic origin grown at two locations for two seasons. Observations on seven grain and seven malt traits were recorded and malting was done with Phoenix® automatic micro-malting system. The correlation studies indicated that the hot water extract (HWE) is correlated with a number of grain (hectolitre weight, plump %, thin %, protein %, TGW and hull %) and malt (friability, homogeneity, wort viscosity, filtration rate and Kolbach Index) traits either positively or negatively. The multiple regression analysis indicated that hectolitre weight, TGW, hull content and malt friability can be used to predict HWE, the ultimately important trait with malting and brewing industry, in early generations of a breeding programme or for initial screening of germplasm accessions.

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A high-performance thin-layer chromatographic (HPTLC) method has been established for simple and rapid quantification of two secoiridoids, swertiamarin and amarogentin, in two Swertia species. HPTLC of secoiridoids was performed on precoated silica 60 F 254 plates with EtOAc-MeOH-H 2 O, 77 + 8 + 8 ( v/v ), as mobile phase. Densitometric determination of the secoiridoids was performed at λ = 235 nm in reflectance/absorbance mode. The method was validated for precision, repeatability, and accuracy. Average recovery of amarogentin and swertiamarin was 94.5 and 96.5%, respectively, showing that the reproducibility of the method was excellent. The method is simple, precise, specific, sensitive, and accurate and can be used for routine quality control of raw materials and herbal formulations.

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Abstract  

This paper deals with the studies on decontaminations of spent ion exchange resin used for purification of plutonium in PUREX process stream. Studies were carried out to optimize the chemical procedure for removal of plutonium and fission products activities form spent Ion Exchange resin. Different metal complexing reagents were tested for leaching out of radionuclides entrapped in irradiated spent ion exchange resin. The experimental results indicate that 0.01 M NaF solution was found the most suitable for removal of plutonium. The mixture of Na2CO3 and sodium salt of EDTA solution was found to be better for decontamination of spent ion exchange resin from beta and gamma activities. Optimized mixture of 0.5 M Na2CO3 and 0.1 M sodium salt of EDTA solution was found to be the most effective for fission product activities removal. After successive multiple contacts using these suitable reagents, the Pu and fission product activities in spent ion exchange resin were brought down to a minimum possible level, making it quite suitable for its long term storage.

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Abstract

Schiff base metal complexes derived from 2-thiophenecarboxylidine-4-anisidine, 3,4-dihydroxy-5-nitrobenzylidine-2-amino-5-methylthiazole and 3,4-dihydroxy-5-nitrobenzylidine-4-chloroaniline have been synthesized and characterized by elemental analysis, IR, UV–Vis, molar conductance and thermal analyses. The complexes are coloured and stable in air at room temperature. The complexes exhibit coordination number to be 4 and 6. The thermal behaviour of metal complexes shows that the hydrated complexes lose water molecules of hydration in the first and then is immediately followed by decomposition of ligand molecules in the subsequent steps.

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