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- Author or Editor: V. K. Sharma x
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Abstract
Radiotracers are extensively used in many industries for trouble shooting and optimization of process parameters leading to considerable savings in time and huge economic benefits. In chemical and petrochemical industries different gases and vapours flowing in the conversion reactors play a major role in the final production. Gaseous radiotracers are ideal to study hydrodynamics of gas phases in process vessels. 41Ar and 79Kr are the preferred gaseous radiotracers for such studies. Owing to the increase in demand from Indian industries for gas phase radiotracers, efforts have been made to produce 41Ar and 79Kr indigenously by irradiation of 40Ar and enriched 78Kr gaseous targets in research reactors. Prequalification of the containers used, safety aspects concerning accidental rupture and mandatory tests necessary for irradiation of gaseous targets in the reactors have been studied. The paper describes some of the important safety aspects involved and the results of trial irradiations on the production of 41Ar and 79Kr radiotracers. Standardization of suitable assay protocols for their regular production and supply for applications in industries is also described.
Nitrogen (N) movement in the soil resulting from the long-term application of fertilizer N is an environmental concern when it reaches the groundwater. The distribution of N in the profile of an alkaline sandy loam soil (Typic Haplustept) and its relationship with N uptake by plants was studied after 22 years of continuous cultivation in an annual crop rotation involving maize (Zea mays L.) and wheat (Triticum aestivum L.). Soil samples were collected to a depth of 1.2 m from the 0-0.15, 0.15-0.30, 0.30-0.45, 0.45-0.60, 0.60-0.90 and 0.90-1.20 m layers and analysed for alkaline KMnO4-oxidisable N (available N) and mineral N (NH4-N and NO3-N). The continuous addition of increasing levels of N resulted in an increase in N content, whereas the combined application of N, P and K caused a decline in its availability. Mineral N (2 M KCl-extractable NH4-N and NO3-N) was the lowest in the N120P35K33.2 treatment plot. The available N and NH4-N decreased with increasing soil depth. However, variations in NO3-N concentration due to differential rates of fertilizer application were observed only to a depth of 0.45 m. This effect was more pronounced in the N180P17.5K33.2 plot. Regression equations were used to predict N uptake by wheat using the N status in different soil layers as independent variables. Multiple regression analysis indicated that the predictability of the relationship between N uptake and available N improved considerably when its status to a soil depth of 0.45 m was included. In the case of NH4-N, a noticeable increase in the coefficient of determination (R2) occurred to a depth of 0.90 m. The R2 value of NO3-N with the N uptake by wheat was quite low in the top layers (to a depth of 0.30 m). However, an increase in the R2 value was observed when lower depths (beyond 0.30 m) were included in the regression analysis, suggesting that the inclusion of subsoil N status is important to achieve better and profitable N supply systems in crop production.
In the present investigation, expression of genes related to Na+ exclusion such as salt overly sensitive (TaSOS1) and Na+/H+ antiporter (TaNHX1) and proline accumulation such as pyrroline-5-carboxylate reductase (P5CR) and glutamate synthase (GOGAT) was studied in seedlings of Kharchia 65 (Kh 65, salt tolerant) and HD 2009 (sensitive) under salt stress (ECe, 12 dSm–1) and controlled conditions. As compared to HD 2009, Kh 65 showed significantly lower accumulation of Na+ (p < 0.01) and higher accumulation of proline (p < 0.05) in leaf blade under salt stress. The relative expression of TaSOS1 increased significantly (p < 0.001) in roots of Kh 65 (4.31-fold) while it decreased in HD 2009. There was significantly higher (p < 0.01) relative expression of TaNHX1 (27.57-fold) in leaf and 3.07-fold in roots of Kh 65 as compared to 3.65- and 0.87-fold increase in leaf and roots of HD 2009, respectively, under salt stress. There was significantly (p < 0.05) higher accumulation of proline as compared to HD 2009 in leaf tissues. There was significantly higher (p < 0.01) expression of P5CR (5.23-fold in leaf and 8.77-fold in the root) and glutamate synthase (6.0- fold in roots) in Kh 65 as compared to HD 2009. The study demonstrated that upregulation of genes for Na+ exclusion in root and compartmentation in leaf and increased proline concentration are associated with tolerance to salinity stress in wheat. The information will be useful for improving wheat genotypes for salt tolerance.
Strawberry fruits of three cultivars viz. Camarosa, Chandler and Doughlas were used to prepare wine by four different methods (control, thermovinification, fermented on the skin and carbonic maceration). Physico-chemical characteristics of the cultivar Camarosa were rated superior to Chandler and Doughlas. The must from the fruits fermented on the skin gave the highest rate of fermentation and ethanol content. The application of various treatments improved the fermentation behaviour of treated strawberry musts compared to the control as revealed by their physico-chemical characteristics. Thermovinified wines had many desirable characteristics such as more total phenols, esters and colour with comparable amount of higher alcohols, volatile acids, ethyl alcohol, sugars and anthocyanin. The carbonic maceration resulted in wines with more alcohol, higher pH, lower acidity, lesser higher alcohol and volatile acids than other wines. Fermented on the skin treated wines were typical for higher amount of anthocyanin, lower reducing sugar and total sugar than the control wines. Thermovinified wines, irrespective of cultivars, scored the highest with respect to most of the sensory quality characteristics. Wines from Camarosa cultivar registered many desirable characteristics such as esters, optimum acidity, more red colour units with comparable contents of alcohol and total phenols, while Chandler cultivar had higher amount of ethyl alcohol, more phenols, anthocyanin than other cultivars. Some of these differences are correlated with their initial characteristics, while others have been influenced by method of vinification. Based on the physico-chemical and sensory qualities, the wines from cv. Camarosa was rated the best, though the wines of all the cultivars were acceptable.
The present research endeavor was undertaken to depict the response of different generations viz., F1, F2, BC1F1, BC1F2, BC1F3, BC1F4 and BC1F5 of triticale × wheat and wheat × rye hybrids towards the different parameters of haploid induction. The experimental material included the different generations obtained utilizing five genotypes of triticale (DT-123, DT-126, TL-2900, TL-2908 and TL-9335), four genotypes of Himalayan rye (Karoki rye, shanoor rye, tino rye and triloki rye) with various elite bread wheat genotypes as parents in wide hybridization programme. The triticale × wheat and wheat × rye recombinants were further subjected to Imperata cylindrica-mediated chromosome elimination approach of doubled haploidy breeding. The variability in the haploid induction parameters was observed to be under genetic control for embryo formation and regeneration, while pseudoseed formation was only affected by auxin treatment. Among the different generations, the backcross generations viz., BC1F1 and BC1F2 were found to exhibit significant positive response towards haploid induction parameters in both triticale × wheat and wheat × rye hybridization. Knowledge of effective generation for haploid induction in triticale × wheat and wheat × rye hybridization not only saved the time and energy but also enhanced the efficiency of haploid induction.
Summary
In this paper we describe a sensitive and reproducible reversed-phase high-performance liquid chromatography (HPLC) method with photodiode-array detection for isolation and quantification of the bioactive hydrophilic constituent 7-(1-O-β-d-galacturonide-4′-(1-O-β-d-glucopyranosyl)-3′,4′,5,7-tetrahydroxyflavone, 1, from the seeds of Cuminum cyminum. Compound 1 was separated isocratically on a C18 preparative column, in high purity, after removal of solvents. The purity and identity of the compound were established by use of LC-mass spectrometry and by spectroscopic techniques (1H and 13C NMR). The purity of 1 was also confirmed by HPTLC.
An investigation to standardize the protocol for in vitro application of colchicine for enhancing the doubled haploid production in wheat was done. Two tetraploid (PDW-314 and A-9-30-1); and two hexaploid (DH-40 and C-306) wheat genotypes were used as maternal parents, whereas, the pollen sources involved Zea mays (cv. Bajaura Makka) and Imperata cylindrica. During the rabi seasons of years 2013–14 and 2014–15, wheat × maize and wheat × I. cylindrica hybridization was carried out followed by treatment of their haploids produced as a result of elimination of chromosomes of maize and I. cylindrica respectively, with varied doses of colchicine for different durations The various doses of colchicine were categorized into two groups: lower doses for longer durations (0.01, 0.025, 0.05% each for 5, 7, 9, 11 hrs) and higher doses for shorter durations (0.05, 0.075, 0.10, 0.15, 0.20, 0.25% each for 5, 4, 3, 2 hrs). The response of different concentrations of colchicine applied for varied durations revealed significant differences for various doubled haploidy parameters viz., per cent survived plants, per cent doubled haploid formation and per cent doubled haploid seed formation. In hexaploid and tetraploid wheats, colchicine doses of 0.075% for 4 hrs and 0.15% for 4 hrs, respectively were established as optimum for enhanced doubled haploid production.
Abstract
Knowledge of the dynamics of HTO in leafy plant–soil system is required to verify models, such as the NORMTRI code, which predict environmental tritium following its release. Tritium concentrations in plants has been evaluated using the code NORMTRI and experimentally by collection of samples of different plants and their soils samples. In the present study, major seasonal crop plants i.e. wheat, mustard, sugar cane, coriander, spinach, potato, were collected beyond Narora Atomic Power Station site boundary and gular, arandi, neem, ashok, amaltas, csuarina leaf samples within NAPS site boundary for analysis of HTO content. Data analysis indicated that HTO in leaf is strongly influenced by atmospheric relative humidity and type of the plant.
Summary
A simple, rapid, and specific thin layer chromatographic (TLC) method has been developed and validated for the simultaneous estimation of icariin and l-arginine from commercial polyherbal formulations for sexual dysfunction. The separation of the methanol extract of these formulations was achieved on silica gel 60 F254 aluminum backed TLC plates by using ethyl acetate-acetone-glacial acetic acid-formic acid-water 12:2:1:2:2 (υ/υ) as mobile phase. Densitometric analysis of icariin and l-arginine was monitored in absorbance mode at 270 and 195 nm, respectively. The linear regression analysis data for the calibration plots for icariin and l-arginine showed good linear relationship with r 2 = 0.9984 +- 0.01 and 0.9968 +- 0.02, in the concentration ranges of 250–750 and 500–1500 ng/spot, respectively. The method was validated for precision, robustness, and recovery. The average percentage recovery was found to be 98.26% for icariin and 99.63% for l-arginine. The limits of detection and quantitation were 72, 116 and 238, 383 ng/spot, respectively, for icariin and l-arginine. Statistical analysis proves that the method is repeatable and selective for the estimation of the targeted drugs. Since the proposed mobile phase effectively resolves the icariin and l-arginine, this method can be applied for the identification and quantitation of these components in herbal extracts and marketed formulations.
Effects of salinity on correlation, path and stress indices, yield and its components were studied in a set of 34 promising rice genotypes collected from various national and international organizations. These genotypes were evaluated in a randomized complete block design with three replications during the wet seasons (kharif) of 2009 and 2010 in normal (ECiw ∼ 1.2 dS/m) and salinity stress (ECiw ∼ 10 dS/m) environments in micro plots at Central Soil Salinity Research Institute (CSSRI), Karnal, India. Grain yield per plant showed positive significant association with plant height, total tillers, productive tillers, panicle length, and biological yield per plant and harvest index under normal environment, whereas grain yield showed positive significant association with biological yield and harvest index under salinity stress. These results clearly indicate that selection of high yielding genotypes would be entirely different under normal and saline environments. The stress susceptibility index (SSI) values for grain yield ranged from 0.35 (HKR 127) to 1.55 (TR-2000-008), whereas the stress tolerance index (STI) values for grain yield ranged from 0.07 (PR 118) to 1.09 (HKR 120). The genotypes HKR 120, HKR 47 and CSR-RIL-197 exhibited higher values of stress tolerance index (STI) in salinity. Under salinity, negative and significant association was shown by SSI and grain yield in contrast to positive and significant association shown by STI and grain yield. These associations could be useful in identifying salt tolerant and sensitive high yielding genotypes. The stress susceptible and stress tolerance indices suggest that the genotypes developed for salinity tolerance could exhibit higher tolerance, adaptability and suitability. Harvest index and biological yield traits emerged as the ideal traits for improvement through selection and could be used to increase the rice productivity under saline stress environments.
